KR20150144687A - Power assist unit and power assist system - Google Patents

Abstract

The power assist unit of the present invention is a power assist unit configured to be connected to the main line of a natural energy generation system that supplies power generated by natural energy to the system, the power assist unit comprising: a branch power line connected to the main line of the natural energy generation system; A first power storage device connected to the branch power line; A power assisted DC / DC converter connected to the branch power line; And a second power storage device connected to the downstream side of the power assisted DC / DC converter.

Description

[0001] POWER ASSIST UNIT AND POWER ASSIST SYSTEM [0002]

The present invention relates to a power assist unit and a power assist system that are connected to a natural energy power generation system and assists the generation of electric power of a natural energy power generation system in a stable manner.

In recent years, the use of natural energy has been promoted for the purpose of global warming countermeasures and the improvement of the self-sufficiency rate of the energy. In particular, the spread of solar power generation and wind power generation is progressing.

However, the power generation using these natural energy has a disadvantage that the output power fluctuates according to the change of the weather or the like.

Therefore, when the natural energy generation system is configured to be connected to the power system, the operation of the power system becomes unstable when the output power of the natural energy generation system changes rapidly.

For example, when a wind power generation system is used in a natural energy generation system, the power supply to the system may become unstable due to changes in the strength of the wind power due to the weather conditions.

Non-Patent Document 1 discloses that there is a normal distribution relationship between the fluctuation magnitude of the short-term output power and the occurrence frequency of the fluctuation of the output power of the wind power generation as a result of the investigation of the fluctuation of the output power of the wind power.

Therefore, in order to mitigate the fluctuation of the output power of the natural energy generation system, it is known as an effective method to connect the storage system to the natural energy generation system.

For example, Patent Document 1 discloses a power transmission system including a power transmission path for sending generated power output from a wind turbine and a wind turbine generator to a power system via a transformer, and a power storage device (a capacitor system) A wind power generation system is disclosed.

Patent Document 2 discloses a power storage device in which a plurality of secondary batteries are disposed between a power source and a load, and these secondary batteries always perform a power compensation operation.

A plurality of secondary batteries are disclosed in Patent Document 2 in which a first group used only for normal power compensation operation and a second group used for power compensation operation are used in place of the recovered secondary battery during a period in which the first group of secondary batteries is repaired and charged, Group of secondary batteries.

Patent Document 3 discloses a DC-DC converter which includes DC power supply means for supplying DC power to a DC bus and first power storage means for performing charge and discharge with a DC bus and second power storage means, A DC power supply system capable of obtaining power efficiency is disclosed.

In Patent Document 3, when the load is small, the control unit cuts off the first operation power supply and the second operation power supply, thereby interrupting the power supply to the DC bus in the DC power supply means and the second power storage means, 2 Power consumption can be reduced by turning off the operation power.

However, when a battery system is installed in a natural energy generation system, natural energy can be influenced by weather and weather conditions, and it is difficult to accurately predict the occurrence of the natural energy. Therefore, There is a difficult problem.

In particular, it is not easy to set the conditions of use such as charging and discharging power and the necessary margin in the stage of installing a natural energy generation system.

Accordingly, it is necessary to provide a large-capacity battery with sufficient free capacity in the battery system, and therefore, the size of the battery system becomes large and a cost problem arises.

Particularly, when a wind power generation system is used as a natural energy generation system, the rotational speed of the windmill changes due to the weather condition at the place where the windmill is installed,

This makes it more difficult to accurately predict the capacity of the required battery.

On the other hand, when the terminal voltage of the battery bank of the battery system is determined, the number of cells of the battery to be used in the battery bank is determined uniquely. Therefore, when it is necessary to expand the battery by parallel connection, A battery having the same number of cells as that of a battery used in an existing battery bank needs to be connected in parallel, and the storage capacity of the battery bank becomes excessive.

It is also necessary to perform charging / discharging at a high rate (for example, a period of about several minutes) for absorbing the fluctuation of the above-described output power.

In other words, the charging and discharging time of the battery system to the battery is short and the number of charging and discharging is increased simultaneously.

When a single battery system (a capacitor system) described in Patent Document 1 is installed in a power generation system requiring such a high rate of charging / discharging, for example, a large capacity of a battery (capacitor) There is a problem that the life of the battery is lowered.

Patent Document 2 discloses a technique of disposing a plurality of secondary batteries between a power source and a load. However, only the first group of secondary batteries is used for normal power compensation operation, and as in the case of Patent Document 1, If the charging / discharging at a high rate that absorbs the fluctuation is performed, the service life of the first group of secondary batteries used at all times is lowered.

It is possible to increase the number of cells of the battery and increase the storage capacity in order to achieve a high rate of charge and discharge. However, as described above, the size of the battery system becomes large and a cost problem arises.

In Patent Document 3, since the first power storage means having the first accumulator and the second accumulator means having the second accumulator and the DC / DC converter are connected to the DC bus, the load is directly connected to the DC bus, The charging and discharging at a high rate can not be performed in the second battery.

[Patent Document 1] Japanese Unexamined Patent Application Publication No. 2007-116825 [Patent Document 2] JP-A-2001-157382 [Patent Document 3] Japanese Laid-Open Patent Publication No. 2012-228028

[Non-Patent Document 1] "Accurate understanding of the capacity of wind power generation from the viewpoint of frequency fluctuation", [online], April 21, 2009, Ministry of Economy, Month 9] <URL: http: //www.meti.go.jp/committee/materials/g50426aj.html>

SUMMARY OF THE INVENTION It is an object of the present invention to provide a power assist unit and a power assist system that can reduce the burden on a battery and prolong the service life of the battery.

The power assist unit according to an embodiment of the present invention is a power assist unit configured to be connected to the trunk of a natural energy generation system that supplies generated power by natural energy to the system, Power line; A first power storage device connected to the branch power line; A power assisted DC / DC converter connected to the branch power line; And a second power storage device connected to the downstream side of the power assisted DC / DC converter.

Wherein the natural energy generation system includes a rotating body rotating due to natural energy, a synchronous generator driven by the rotating body, and a power conversion unit provided between the synchronous generator and the system, A first power system inverter for AC / DC conversion and a second power system inverter for DC / AC conversion, the branch power line being connected to a DC trunk line connecting between the first power system inverter and the second power system inverter Can be connected.

Wherein the natural energy generation system includes a rotating body rotated by natural energy, an induction generator driven by the rotating body, and a power conversion unit installed in a secondary winding of the induction generator, wherein the power conversion unit includes an AC / And a second power system inverter for DC / AC conversion, the branch power line being connected to a DC power line connecting between the first power system inverter and the second power system inverter .

Wherein the natural energy generation system includes a power generation device for generating direct current power by receiving natural light as natural energy and a power conversion part provided between the power generation device and the system, and the branch power line is connected between the power generation device and the power conversion part It can be connected to the connecting DC trunk line.

The trunk line is an AC trunk line, and further includes an inverter connected to the AC trunk line. The branch power line is connected to the downstream side of the inverter, and can be connected to the AC trunk line via the inverter.

Wherein the natural energy generation system includes a rotating body rotating due to natural energy, a synchronous generator driven by the rotating body, a generator installed between the synchronous generator and the system, And the inverter may be connected to an AC trunk line connecting between the power converter and the system.

The output voltage of the first power storage device may be higher than the output voltage of the second power storage device.

And a DC interrupter installed in a power line of the first power storage device among the power lines after the branch of the branch power line to electrically disconnect or conduct the first power storage device and the branch power line.

The natural energy is wind energy, and the rotating body can rotate due to the wind energy.

The natural energy is hydraulic energy, and the rotating body can rotate due to the hydraulic energy.

Wherein the inverter is electrically connected to a second system different from the system,

When the power supply from the natural energy generation system to the system is stopped or the power supply to the system side is stopped, the power supply from the first power storage device and the second power storage device And can be powered by the second system.

Wherein the natural energy generation system includes a general control section for outputting a general control signal for controlling charging and discharging of the first power storage device and the second electric power storage device and a control section for receiving the general control signal from the general control section, A second battery control signal for controlling charging and discharging of the second power storage device, and a second battery control signal for controlling charging and discharging of the first power storage device, Wherein the first power storage device and the second power storage device are controlled by the general control section via the interface section, A first charge / discharge control in which the charge / discharge of the other device is stopped and at the same time the charge / discharge of the other device is stopped; The second charge-discharge control value is the charge and discharge is stopped may be controlled to be selected in turn.

Wherein the general control signal outputted by the general control section includes a converter control command for on-off controlling the power assist DC / DC converter, and the interface section controls the power assist DC / DC converter in response to the converter control command Converter control signal to the power assist DC / DC converter.

The power assist system according to an embodiment of the present invention includes a power assist unit and a collective control unit for controlling charge and discharge of the first power storage device and the second power storage device, A first charge / discharge control for driving one of the power storage device and the second power storage device to charge / discharge and stop charging / discharging of another device; and a charge / And a second charge / discharge control for stopping the charge / discharge control.

Wherein the general control unit charges and discharges the apparatus so that the SOC becomes equal to or less than Q1% in the first charge / discharge control and stops charging / discharging the other apparatus, and in the second charge / Discharging is stopped and Q1 = 50 and Q1 < Q2 = 100 are met, and the charging / discharging of the above-mentioned second charging / Time can be short.

The power assist system according to an embodiment of the present invention includes a power assist unit and a collective control unit for controlling charge and discharge of the first power storage device and the second power storage device, A first charge / discharge control for driving one of the power storage device and the second power storage device to charge / discharge and stop charging / discharging of another device; and a charge / And the second charge / discharge control for stopping the charge / discharge control.

Wherein the general control unit charges and discharges the apparatus so that the SOC becomes equal to or less than Q1% in the first charge / discharge control and stops charging / discharging the other apparatus, and in the second charge / Discharging is stopped and Q1 = 50 and Q1 < Q2 = 100 are met, and the charging / discharging of the above-mentioned second charging / Time can be short.

The power assist system according to an embodiment of the present invention includes a power assist unit and a collective control unit for controlling charge and discharge of the first power storage device and the second power storage device, A first charge / discharge control for charging / discharging any one of the power storage device and the second power storage device so that the SOC is Q1% or less, satisfying Q1 = 50 and stopping charging / A second charge / discharge control for satisfying + Q2 = 100, charging / discharging the device so that the SOC of the device is not more than Q1%, and charging / discharging the device so that the SOC of the device is Q1% .

The power assist system according to an embodiment of the present invention includes a power assist unit and a collective control unit for controlling charge and discharge of the first power storage device and the second power storage device, A first charge / discharge control for charging / discharging any one of the power storage device and the second power storage device so that the SOC is Q1% or less, satisfying Q1 = 50 and stopping charging / A second charge / discharge control for satisfying + Q2 = 100, charging / discharging the device so that the SOC of the device is not more than Q1%, and charging / discharging the device so that the SOC of the device is Q1% .

Q1 may be 50, and Q2 may be 100.

Wherein said main control unit receives a power monitoring signal indicating the state of the generated power and calculates a charge / discharge command waveform corresponding to an assist power of said branch power line in response to said power monitoring signal, Discharge control waveform and the second charge / discharge control waveform so that the charge / discharge command waveform becomes the charge / discharge command waveform.

Wherein the charge control command waveform includes a triangular approximation wave approximating a square wave combination of a triangular wave having an amplitude and a charge / discharge cycle calculated in accordance with the power monitoring signal, and a first charge / Discharge command to be applied to the second charge / discharge control, and to control the first power storage device and the second power storage device.

Wherein said main control unit receives a power monitoring signal indicating the state of the generated power and calculates a charge / discharge command waveform of a triangle wave corresponding to an assist power of said branch power line in accordance with said power monitoring signal, Discharge command to be applied to the discharge control and the second charge / discharge command to be applied to the second charge / discharge control, thereby controlling the first power storage device and the second power storage device.

Wherein the integrated control unit receives a power monitoring signal indicating a state of the generated power and calculates a charge and discharge command waveform corresponding to an assist power of a power line between the inverter and the AC main line in accordance with the power monitoring signal, The first charge / discharge control and the second charge / discharge control can be performed so that the charge / discharge waveform of the charge / discharge waveform becomes the calculated charge / discharge waveform.

Wherein the general control unit is configured to charge and discharge the SOC of any one of the first power storage device and the second power storage device to Q1% or less while at the same time stop charging / Discharge control so that Q1 + Q2 = 100 and the SOC of the above device is Q1% or less, and at the same time, the SOC of the other device is Q1% or more and Q2% or less. Discharge control of the first charge / discharge control and the second charge / discharge control of the second charge / discharge control, and the second charge / At a predetermined ratio.

Wherein the general control unit is configured to be capable of on / off control of driving and stopping the power assist DC / DC converter, and drives the power assist DC / DC converter when driving the charge / discharge operation of the second power storage device, The power assist DC / DC converter can be stopped when the charge / discharge operation of the second power storage device is stopped.

Wherein the general control section is configured to be capable of on-off control of driving and stopping of the inverter, and drives the inverter when driving the charge / discharge operation of the first power storage device or the second power storage device, The storage device and the second power storage device may stop the inverter when it does not drive the charge / discharge operation.

According to the embodiment of the present invention, it is possible to provide a power assist unit and a power assist system that can reduce the burden on the battery and extend the service life of the battery.

1 is a diagram showing a configuration example of a wind power generation system and a power assist system according to a first embodiment.
2 is a diagram showing an example of the power waveform of the first power detection signal.
3 is a diagram showing an example of the waveform of the first charge / discharge pattern.
4 is a diagram showing an example of the waveform of the second charge / discharge pattern.
5 is a diagram showing an example of the waveform of the third charge / discharge pattern.
6 is a diagram showing an example of the waveform of the fourth charge / discharge pattern.
7 is a diagram showing an example of the waveform of the fifth charge / discharge pattern.
8 is a diagram showing a first modification of the wind power generation system and the power assist system according to the first embodiment.
9 is a diagram showing a second modification of the wind power generation system and the power assist system according to the first embodiment.
10 is a view showing a third modification of the wind power generation system and the power assist system according to the first embodiment.
11 is a view showing a fourth modification of the wind power generation system and the power assist system according to the first embodiment.
12 is a diagram showing a configuration example of a wind power generation system and a power assist system according to the second embodiment.
FIG. 13 is a diagram showing an example of the waveform of the charge / discharge pattern 6. FIG.
14 is a diagram showing an example of the waveform of the charge / discharge pattern 7. As shown in Fig.
15 is a diagram showing a first modification of the wind power generation system and the power assist system according to the second embodiment.
16 is a diagram showing a second modification of the wind power generation system and the power assist system according to the second embodiment.
17 is a diagram showing a third modification of the wind power generation system and the power assist system according to the second embodiment.
18 is a view showing a fourth modification of the wind power generation system and the power assist system according to the second embodiment.
19 is a diagram showing a fifth modification of the wind power generation system and the power assist system according to the second embodiment.
20 is a view showing a sixth modified example of the wind power generation system and the power assist system according to the second embodiment.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, detailed description of well-known functions or constructions that may obscure the subject matter of the present invention will be omitted. It should be noted that the same constituent elements are denoted by the same reference numerals as possible throughout the drawings.

The terms and words used in the present specification and claims should not be construed to be limited to ordinary or dictionary meanings and the inventor is not limited to the concept of terminology for describing his or her invention in the best way. It should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, It is to be understood that equivalents and modifications are possible. Also, the terms first, second, etc. are used for describing various components and are used only for the purpose of distinguishing one component from another component, and are not used to define the components.

&Lt; Embodiment 1 >

- Configuration of the system -

1 is a diagram showing a configuration example of a wind power generation system and a power assist system according to a first embodiment.

As a natural energy generation system, a wind power generation system 10 is configured to be connected to a system 40, and specifically includes a windmill 11 as a rotating body rotating with wind, a windmill 11 connected to a rotary shaft of a windmill 11, And a power conversion section 13 for converting power generated by the synchronous generator 12 and the synchronous generator 12,

The power conversion section 13 is connected to a first power system inverter (hereinafter, referred to as &quot; first power system inverter &quot;) that receives AC power generated by the synchronous generator 12 via the trunk L11 and converts And a second power system inverter 13b for converting the DC power of the main line 13a and the main line L12 into AC power (DC / AC conversion) and outputting it to the main line L13.

The trunk line L13 is connected to the system 40 through the transformer 42. [

The output power of the wind power generation system 10 is transformed by the transformer 42 and supplied to the system 40. [

The electric power supplied from the wind power generation system 10 and the grid power supply 41 is supplied to the factory 44 or the home 46 via the transformer 43 or the transformer 45.

The power assist system 2 includes a power assist unit 20 connected to the trunk L12 of the wind power generation system 10 and a collective control unit 29 for collectively controlling the power assist unit 20. [

The power assist unit 20 includes a breaker 21 whose one end is connected to the main line L12 of the wind power generation system 10, a branch power line L22 connected to the other end of the breaker 21, A power assist DC / DC converter 24 connected to the branch power line L22 and a power line L23 on the downstream side of the power assist DC / DC converter 24. The first battery bank 23 as the first power storage device, A second battery bank 25 as a second power storage device connected via an interface section 26, and the like.

In the present invention, in the case of the power assist unit 20, a side close to the main line L12 is referred to as an upstream side, and a side far from the main line L12 is referred to as a downstream side.

The circuit breaker 21 is configured to be able to change the interruption / conduction of the trunk L12 of the wind power generation system 10 and the branch power line L22 of the power assist unit 20, The main line L12 and the branch power line L22 are turned on when the first battery bank 23 and / or the second battery bank 25 are charging / discharging, for example, when the assist operation is performed.

On the other hand, when an overcurrent is generated or an abnormality occurs (for example, when an abnormal voltage due to a lightning stroke occurs), it is automatically or under the control of the general control unit 29 (not shown in the control signal line) The connection of the power line L22 is cut off.

The first battery bank 23 is a battery bank configured to be capable of charging / discharging at a high rate, and is composed of, for example, a lithium ion battery.

The first battery bank 23 is configured such that the terminal voltage becomes equal to the trunk L12 of the wind power generation system 10. [

For example, the terminal voltage of the first battery bank 23 is 800V.

The second battery bank 25 is a battery bank configured to be capable of charging / discharging at a high rate, and is made of, for example, a lithium ion battery.

In addition, the second battery bank 25 is controlled such that the terminal voltage is equal to or lower than the terminal voltage of the first battery bank 23.

For example, when the terminal voltage of the first battery bank 23 is 800 V, the terminal voltage of the second battery bank 25 may be configured to be 3 V or more and 600 V or less.

The terminal voltages of the first battery bank 23 and the second battery bank 25 can be set by changing the type of the cell used for the lithium ion battery or the number of cells.

The terminal voltage of the second battery bank 25 is not limited to 600 V or less.

For example, the terminal voltage of the second battery bank 25 may be 600 V or more, and may be the same as the terminal voltage of the first battery bank 23.

In the present invention, the first battery bank 23 and the second battery bank 25 are made of lithium ion batteries. However, it is also possible to use other types of batteries such as lead batteries, NaS batteries, and Ni-Cd batteries This is the same in the following description.

The power assist DC / DC converter 24 is connected to the output terminal of the second battery bank 25 and can increase the voltage of the output terminal to be connected to the branch power line L22, Is set in a range according to the setting range of the terminal voltage of the bank (25).

By adopting such a configuration, it is possible to flexibly change the power storage capacity of the second battery bank 25. [

Thus, for example, when the entire power storage capacity of the power assist unit 20 needs to be changed after the wind power generation system 10 and the power assist unit 20 are installed, depending on the use conditions, It is possible to finely adjust the capacity by changing the storage capacity, such as changing the number of cells in the battery 25.

The power assist DC / DC converter 24 is provided between the first battery bank 23 and the second battery bank 25 so that the first battery bank 23 and the second battery bank 25 25 and the power assist DC / DC converter 24, a state in which the voltage of one of the battery banks is high and a state in which the voltage of the other battery bank is high are automatically alternately formed.

In other words, the first battery bank 23 and the second battery bank 25 automatically and automatically generate a rest period.

For example, when the voltage for charging / discharging from the first battery bank 23 is high, the branch power line L22 is driven by the charge / discharge from the first battery bank 23, and the power assist DC / And the charging and discharging of the second battery bank 25 is stopped.

In other words, the second battery bank 25 is in a rest state.

Conversely, when the voltage for charging / discharging from the second battery bank 25 is high, the branch power line L22 is driven by the charge / discharge from the second battery bank 25 output via the power assist DC / DC converter 24 And the power assist DC / DC converter 24 becomes a barrier, so that the charge / discharge of the first battery bank 23 is stopped.

In other words, the first battery bank 23 is in a rest state.

Thereby, even when a high rate of charge and discharge is performed in the first battery bank 23 and the second battery bank 25 in the power assist operation of the wind power generation system 10, When compared, it is possible to realize a long life of the battery.

On the other hand, in the power assist unit 20 of Fig. 1, the circuit breaker 21 has an optional configuration, and the same effect can be obtained without the circuit breaker 21. Fig.

The general control section 29 outputs the first power detection signal SM1 as a power monitoring signal indicating the power status of the trunk L12 before the assist power is supplied by the power assist system 2 (power assist unit 20) And outputs an integrated control signal SC1 for controlling the first battery bank 23, the power assist DC / DC converter 24 and the second battery bank 25 to the interface unit 26. [

The collective control unit 29 receives the first battery monitoring signal SM2 indicating the battery voltage, the charge / discharge current and the charge / discharge power from the first battery bank 23, And monitors the situation.

Similarly, the general control section 29 receives the second battery monitoring signal SM3 indicating the battery voltage, the charge / discharge current, and the charge / discharge power from the second battery bank 25, And so on.

The general control unit 29 receives the second power detection signal SM4 indicating the power status of the trunk L13 at which the AC power is transmitted after the power assist unit 20 has performed the power assist, I.e., whether or not the desired power assist operation has been performed.

On the other hand, the general control section 29 receives, instead of the power state of the trunk L12, a signal indicating the power state of the trunk L11 supplied with the alternating-current power generated by the synchronous generator 12 as the first power detection signal SM1 And output the collective control signal SC1 generated in accordance with the first power detection signal SM1 to the interface unit 26. [

- Power stabilization control (charge / discharge control) -

&Lt; Variation of generated power of wind power generation system >

2A and 2B are diagrams showing an embodiment of the waveform of the first power detection signal SM1 in the wind power generation system 10 of FIG.

In other words, in the wind power generation system 10, an example of the generated power waveform after power conversion by the power conversion unit 13 is shown.

In Fig. 2A, the solid line is the waveform of the first power detection signal SM1, and the one-dot chain line is the profile waveform of the wind power generation system 10. Fig.

FIG. 2B is a diagram showing the variation width of the first power detection signal SM1 with respect to the profile waveform (dot-dash line in FIG. 2A), and the time min on the abscissa axis is, for example, 20 min.

In FIG. 2B, the fluctuation width of the allowable output power for stably supplying power from the wind power generation system 10 to the system 40 is P1, the threshold of the upper limit according to the fluctuation of the output power is P2, And the threshold of the lower limit according to the variation is P3.

For example, in the case where the generated power of the wind power generation system is 4 MW, the value of P1 may be set to 500 kW.

For example, P2 may be set to +250 kW, and P3 may be set to -250 kW.

The permissible fluctuation widths P1 to P3 are not limited to these values and may be arbitrarily settable values.

According to the research results described in the above non-patent document 1, there is a normal distribution relationship between the variation magnitude of the output power of the short period shown in FIG. 2B and the occurrence frequency of such variation.

In other words, in FIG. 2B, the fluctuation magnitude, occurrence frequency, and output power fluctuation of the portion where the fluctuation of the output power exceeds the upper limit threshold P2 (upper right slanting line of FIG. 2B) (The lower right slanting line in Fig. 2B), and the frequency of occurrence of the fluctuation in the portion below the slanting portion (the right lower slanting line in Fig. 2B).

Therefore, the present inventor has found that the variation width of the electric power from the wind power generation system 10 to the system 40 is limited within a predetermined range (for example, within P1), and therefore, Discharge control command to the first battery bank 23 and the second battery bank 25 from the general control unit 29. [

Hereinafter, the specific charge / discharge control by the general control section 29 will be described in detail.

In the following description, it is assumed that the fully charged capacity of the first battery bank 23 and the second battery bank 25 is 4C.

Therefore, in the following description, charging / discharging with the SOC (State Of Charge) of 100% in the first battery bank 23 indicates charging / discharging with the charging / discharging capacity 4C, The same applies to the case.

The charging / discharging at an SOC of 0% or more and 50% or less is referred to as charging / discharging at a charging / discharging capacity of 0C or more and 2C or less.

Here, SOC is the ratio of the present charge capacity to the full charge capacity.

The charging capacity 1C means a current value in which the cells having the capacity of the nominal capacity value are charged in the constant current and the charging is completed in one hour.

Likewise, the discharge capacity 1C means a current value at which a cell having a capacity of a nominal capacity value is discharged in a constant current and the discharge is completed in one hour.

Charging and discharging at a charging / discharging capacity of 0C or more and 2C or less is performed at a charge capacity of 0C or more and 2C or less and discharging at a discharge capacity of 0C or more and 2C or less.

For convenience of explanation, the full charge capacity is 4C, but the full charge capacity may be 4C or higher.

<Charge / discharge control>

First, the general control section 29 receives the first power detection signal SM1 and calculates a charge / discharge pattern for stabilizing the output power of the wind power generation system 10 in accordance with the first power detection signal SM1 do.

Specifically, the first power detection signal SM1 is compared with the profile waveform to select a predetermined pattern (waveform shape) to be used for the charge / discharge pattern, and the charge / discharge capacity applied to the charge / discharge pattern, .

The waveform shape selected by the general control section 29 as a predetermined charge / discharge pattern may be, for example, a waveform approximated to a triangular wave by combining a square wave, a triangular wave, and a square wave.

Hereinafter, charge / discharge control will be described in detail with an example of a charge / discharge pattern.

(First charge / discharge pattern)

3 is a view showing an example in which a square wave is selected as a charge / discharge pattern.

Specifically, in FIG. 3A, the collective control section 29 selects a square wave as a charge / discharge pattern in accordance with the first power detection signal SM1, and determines the charge / discharge capacity to be applied to the charge / This embodiment is shown in FIG.

In addition, an example is shown in which one cycle (T10 to T11) of charging and discharging is 5 minutes, and a charging period and a discharging period in one cycle period are 2.5 minutes, respectively.

Here, one cycle period refers to a period when charging and discharging are performed alternately, from the start of charging to the end of discharging by one cycle, and the same applies hereafter.

Then, the general control section 29 disassembles the charge / discharge pattern, and generates a first battery control pattern for controlling the first battery bank 23 and a second battery control pattern for controlling the second battery bank 25, .

At this time, the first and second battery control patterns are generated so that a rest time at which charging and discharging is stopped is set in the first battery bank 23 and the second battery bank 25, respectively.

In accordance with such a charge / discharge pattern, a power converter control pattern for controlling the power assist DC / DC converter 24 is generated.

Thereafter, the collective control unit 29 outputs to the interface unit 26 the collective control signal SC1 to which the information of the first and second battery control patterns and the information of the power converter control pattern are added.

The interface unit 26 outputs the first battery control signal SC2 to the first battery bank 23 as a charge / discharge command generated in accordance with the general control signal SC1 received from the general control unit 29. [

Also, the second battery control signal SC3, which is a charge / discharge command generated in the same manner, is output to the second battery bank 25. [

The interface unit 26 also outputs a converter control signal SC4 which is an on / off control command of the power assist DC / DC converter 24 generated in accordance with the collective control signal SC1 received from the general control unit 29, And outputs it to the DC / DC converter 24.

Thus, the general control section 29 can collectively control the first battery bank 23, the power assist DC / DC converter 24, and the second battery bank 25 via the interface section 26. [

With such a batch control, it is possible to optimize the substrate on which the collective control section 29 is mounted, prevent control delay, and reduce the influence of noise.

In addition, by providing the interface unit 26 in the power assist unit 20 and enabling control through the interface unit 26, the convenience can be improved.

For example, when a power assist system according to the present invention is installed in a conventional wind power generation system, it is unnecessary to replace a control part (for example, a power control application part) of an existing wind power generation system. Can be easily utilized as a general control unit according to the present invention.

In the following description, when the general control unit 29 controls the first battery bank 23, the power assist DC / DC converter 24, and the second battery bank 25, the interface unit 26 There is a case in which the description that the control is interposed is omitted and that the collective control section 29 merely performs these controls.

More specifically, as shown in FIG. 3B, the collective control unit 29 firstly sets one cycle period from T10 to T11 and one cycle from T12 to T13 as the first battery control pattern (first battery control signal SC2) Discharge command based on the charge / discharge pattern of Fig. 3A to the first battery bank 23 during the period of time shown in Fig.

Accordingly, the first battery bank 23 is charged and discharged at an SOC of 100% (SOC 0% to 100%).

On the other hand, the general control section 29 outputs a charge / discharge stop command to the first battery bank 23 in one cycle period from T11 to T12 and one cycle period from T13 to T14, and the first battery bank 23 ) Is stopped to provide a rest time.

After T14, control from T10 to T14 is repeated.

As shown in FIG. 3C, the general control section 29 includes a first battery control pattern (second battery control signal SC3), one cycle period from T10 to T11, and one cycle period from T12 to T13 Discharge stop command to the second battery bank 25 to stop the charging and discharging of the second battery bank 25 and turn off the power assist DC / DC converter 24 by the converter control signal SC4 And provides a dwell time to the second battery bank 25 and the power assist DC / DC converter 24.

On the other hand, the collective control unit 29 outputs a charge / discharge command based on the charge / discharge pattern in Fig. 3A to the second battery bank 25 in one cycle period from T11 to T12 and one cycle period from T13 to T14, And controls the assist DC / DC converter 24 to be ON.

Thus, the second battery bank 25 is charged and discharged at an SOC of 100% (SOC 0% to 100%).

After T14, control from T10 to T14 is repeatedly performed.

The charge and discharge powers of the first battery bank 23 and the second battery bank 25 in the branch power line L22 are synthesized through the control method described above so that the charging and discharging electric power as shown in Fig. L22.

3A is transmitted from the power assist unit 20 to the trunk L12 to generate a power assist based on the comparison result between the first power detection signal SM1 and the profile waveform, Operation is performed.

Thus, the fluctuation of the output power of the natural energy generation system can be absorbed.

In this power assist operation, the first battery bank 23 and the second battery bank 25 each have a rest period for each cycle period.

As described above, even when charging / discharging at a high rate as shown in Figs. 3A to 3C is performed by providing the rest time in the first battery bank 23 and the second battery bank 25, The battery life can be prolonged.

In addition, since the power assist DC / DC converter 24 is controlled to be off during the period in which the second battery bank 25 is stopped, there is an advantage that the drive ratio of the power assist DC / DC converter 24 can be reduced have.

Thus, the efficiency of the entire power assist unit 20 can be improved.

Concretely, for example, the efficiency of the entire power assist unit 20 can be improved by 10% or more.

3B and 3C, the first battery bank 23 and the second battery bank 25 are described as having a dwell time for each cycle period, but the present invention is not limited thereto.

For example, it is also possible to have a rest period for every arbitrary cycle of two or more cycles.

In addition, the first battery bank 23 and the second battery bank 25 may have different rest times.

3B and 3C, the first battery bank 23 and the second battery bank 25 are described as being charged and discharged at an SOC of 100% (SOC is 0% or more and 100% or less). However, But is not limited thereto.

For example, the first battery bank 23 and the second battery bank 25 may be charged and discharged at an arbitrary R1% (SOC 0% to R1%) of less than 100% of the SOC.

Thus, the control by the general control section 29 can be simplified.

In FIGS. 3A to 3C, the power assist DC / DC converter 24 is controlled to be off during the period in which the second battery bank 25 is stopped. However, the present invention is not limited to this.

For example, the power assist DC / DC converter 25 including the period during which the second battery bank 25 is stopped and the period during which the first battery bank 23 and / or the second battery bank 25 is charged and discharged, (Not shown).

(Second charge / discharge pattern)

4 is a diagram showing an embodiment employing a waveform (hereinafter referred to as a triangular approximation wave) approximated to a triangular wave by combining square waves as a charge / discharge pattern.

Specifically, in the example of FIG. 4A, the general control section 29 selects a triangular approximation wave as a charge / discharge pattern in accordance with the first power detection signal SM1, and based on the triangular wave as the basis of the triangular approximation wave, The charging period T20 to T23 and the discharging period T23 to T26 in the one cycle period are set to 10 minutes and the maximum value of the capacity is 4C and the maximum value of the discharging capacity is 4C. ) Are calculated as 5 min (see the broken line in Fig. 4A).

As shown by the solid line in FIG. 4A, the general control section 29 generates a triangular approximation wave, which is a combination of rectangular waves, in accordance with the calculated charge / discharge pattern (triangular wave).

Next, the general control section 29 disassembles the triangular approximation wave to generate a first battery control pattern for controlling the first battery bank 23 and a second battery control pattern for controlling the second battery bank 25 .

At this time, the first and second battery control patterns are generated so that the first battery bank 23 and the second battery bank 25 are provided with a resting time for stopping charging and discharging.

Thereafter, the general control section 29 outputs the first battery control signal SC2 (first battery control pattern) shown in Fig. 4B to the first battery bank 23 via the interface section 26, And outputs the second battery control signal SC3 (second battery control pattern) shown in Fig. 4C to the second battery bank 25. [

The general control section 29 generates a power conversion section control pattern for controlling the power assist DC / DC converter 24 according to the charge / discharge pattern, and outputs the converter control signal SC4 (power conversion section control pattern) To DC / DC converter 24 as power assist.

For example, the general control section 29 may control the charging / discharging period of the first battery bank 23 and / or the second battery bank 25 during the period in which the charge / And outputs a converter control signal SC4 for on-controlling the power assist DC / DC converter 24. [

At a period from T20 to T21 (for example, 2 (min)), the collective control unit 29 sets the first battery bank 23 to SOC 50% (SOC0% to 50 %) (See Fig. 4B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 ).

In the period from T21 to T22 (for example, 1 minute), the collective control unit 29 sets the idle time in the first battery bank 23 by the first battery control signal SC2 (see Fig. 4B).

The collective control unit 29 charges the second battery bank 25 at SOC 100% (SOC 0% to 100%) by the second battery control signal SC3 (see FIG. 4C).

In the period from T22 to T24 (for example, 4 minutes), the collective control unit 29 sets the first battery bank 23 to SOC 50% (SOC 0% to 50%) by the first battery control signal SC2, (See Fig. 4B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 (see FIG. 4C) .

In the period from T24 to T25 (for example, 1 minute), the collective control unit 29 sets the idle time in the first battery bank 23 by the first battery control signal SC2 (see FIG. 4B) .

In addition, the general control unit 29 discharges the second battery bank 25 at SOC 100% (SOC 0% to 100%) by the second battery control signal SC3 (see FIG. 4C).

In the period from T25 to T26 (for example, 2 minutes), the collective control unit 29 sets the first battery bank 23 to SOC 50% (SOC 0% to 50%) by the first battery control signal SC2, (See Fig. 4B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 ).

After T26, the general control section 29 repeatedly performs the control from T20 to T26.

Charge / discharge power of the first battery bank 23 and the second battery bank 25 is synthesized through the above-described control method, and the charge / discharge power as shown in FIG. 4A is transmitted to the branch power line L22.

4A is transmitted from the power assist unit 20 to the trunk L12 to generate a power assist based on the comparison result between the first power detection signal SM1 and the profile waveform, Operation is performed.

Thus, the fluctuation of the output power of the natural energy generation system can be absorbed.

In this power assist operation, the collective control unit 29 performs charge / discharge control so as to provide idle periods for the first battery bank 23 and the second battery bank 25, respectively.

Accordingly, even when charging / discharging at a high rate as shown in Figs. 4A to 4C is performed, the first battery bank 23 and the second battery bank 25 have a longer life .

In addition, the unification control section 29 charges and discharges the first battery bank 23 at a SOC of 50% or less (SOC is 0% or more and 50% or less) even when a downtime is provided for the first battery bank 23 and charging and discharging are performed have.

By performing such charging / discharging control, when charging / discharging is performed in an SOC of 50% or more, for example, SOC 100% (SOC 0% to 100% or less) or SOC 50% (SOC 50% The battery life can be prolonged.

On the other hand, the collective control unit 29 charges and discharges the second battery bank 25 at an SOC of 100% (SOC 0% to 100%), but the pause time is longer than the first battery bank 23 Period.

For example, in this embodiment, the downtime is controlled to be four times the charge / discharge period.

By performing such control, the power assist unit 20 including the first battery bank 23 and the second battery bank 25 is charged and discharged with the charge / discharge of SOC 100% (SOC 0% to 100% The overall life span can be improved.

On the other hand, the general control section 29 provides the charge / discharge command (hereinafter referred to as a first charge / discharge command) shown in FIG. 4B to the first battery bank 23, Discharge command to the first battery bank 23 and the second charge / discharge command to the second battery bank 25, the first charge / discharge command is supplied to the first battery bank 23 The long life of the first battery bank 23, the second battery bank 25, and the entire power assist unit 20 can be realized.

In the description of this embodiment, when the first battery bank 23 is driven to be charged / discharged, the general control unit 29 performs charging / discharging at an SOC of 50% (SOC 0% to 50% Discharge of the battery bank 25 is performed at the SOC 100% (SOC 0% to 100%). However, the present invention is not limited to this.

For example, when the first battery bank 23 is charged / discharged, the SOC is charged and discharged at Q1% (Q1 = 50, at the same time, SOC 0% to Q1% 25) is charged / discharged in the charge / discharge drive of the first battery bank 23, the first battery bank 23, the second battery bank 23, and the second battery bank 23, when SOC is Q2% (Q1 <Q2 = 100 and at the same time, 2 battery bank 25 and power assist unit 20 as a whole can be realized.

In addition, although the general control section 29 is configured to turn on the power assist DC / DC converter 24 during the period in which the charge / discharge pattern in Fig. 4A is outputted, the present invention is not limited thereto.

For example, the general control section 29 may be configured to turn off the power assist DC / DC converter 24 during a period in which the second battery bank 25 is stopped.

By performing such control, the drive ratio of the power assist DC / DC converter 24 can be reduced, and therefore, the efficiency of the entire power assist unit 20 can be improved.

The general control section 29 controls the second battery bank 25 so that the downtime is four times that of the charge / discharge period, but the downtime is set longer than that of the first battery bank 23 This may be shorter than four times or four times or more. In this case, the effect of extending the power assist unit 20 is obtained.

(Third charge / discharge pattern)

5 is a diagram showing an embodiment in which, when the triangular approximation wave is selected as the charge / discharge pattern, the collective control section 29 generates another charge / discharge pattern.

More specifically, in the example of Fig. 5A, the general control section 29 selects a triangular approximation wave in accordance with the first power detection signal SM1, and as a charge / discharge pattern (triangular wave) And a triangular wave like the broken line of Fig.

The general control section 29 generates a triangular approximation wave, which is a combination of rectangular waves, in accordance with the calculated charge / discharge pattern (triangular wave), as in FIG. 4A.

Next, the general control section 29 disassembles the triangular approximation wave to generate a first battery control pattern for controlling the first battery bank 23 and a second battery control pattern for controlling the second battery bank 25 .

Thereafter, the general control section 29 outputs the first battery control signal SC2 shown in Fig. 5B to the first battery bank 23 via the interface section 26, and the second battery control signal SC2 shown in Fig. And outputs the signal SC3 to the second battery bank 25. [

The general control section 29 generates a power conversion section control pattern for controlling the power assist DC / DC converter 24 based on such charge / discharge pattern, and outputs a converter control signal SC4 (power conversion section control pattern) To DC / DC converter 24 as power assist.

For example, the general control section 29 outputs a converter control signal SC4 for on-controlling the power assist DC / DC converter 24 during the period in which the charge / discharge pattern of Fig. 5A is output.

5B, in a period from T20 to T26 (for example, 10 min), the collective control unit 29 sets the first battery bank 23 to SOC 50% (SOC 0%) by the first battery control signal SC2, Or more and less than or equal to 50%).

On the other hand, in Fig. 5C, in a period from T20 to T21 (for example, 2 min), the collective control unit 29 stops charging and discharging of the second battery bank 25 by the second battery control signal SC3 And a rest time is set in the second battery bank 25. [

The SOC 50% (SOC 50% to 100%) of the second battery bank 25 is controlled by the second battery control signal SC3 in the period from T21 to T22 (for example, 1 minute) Or less).

In the period from T22 to T24 (for example, 4 minutes), the collective control unit 29 stops the charging and discharging of the second battery bank 25 by the second battery control signal SC3, (25).

In the period from T24 to T25 (for example, 1 minute), the collective control unit 29 sets the second battery bank 25 to SOC 50% (SOC 50% to 100%) by the second battery control signal SC3, The following section).

In the period from T25 to T26 (for example, 2 minutes), the collective control unit 29 stops the charging and discharging of the second battery bank 25 by the second battery control signal SC3, (25).

After T26, the general control section 29 repeatedly performs the same control as T20 to T26 for the first battery bank 23 and the second battery bank 25. [

Charging / discharging electric power of the first battery bank 23 and the second battery bank 25 is synthesized by performing the above-described control, so that charge / discharge electric power as shown in FIG. 5A is transmitted to the branch power line L22.

5A is transmitted from the power assist unit 20 to the trunk L12 to generate a power assist based on the comparison result of the first power detection signal SM1 and the profile waveform, Operation is performed.

Thus, the fluctuation of the output power of the natural energy generation system can be absorbed.

In this power assist operation, the collective control unit 29 performs charge / discharge control so as to provide the second battery bank 25 with a rest time.

Therefore, even when charging / discharging at a high rate as shown in Fig. 5C is performed, it is possible to realize a long life of the battery including the second battery bank 25 have.

In this embodiment, the collective control unit 29 does not perform the control for providing the idle time to the first battery bank 23. [

However, the collective control unit 29 charges and discharges the first battery bank 23 at an SOC of 50% (SOC 0% to 50%) throughout the entire power assist operation (charge / discharge operation).

By performing such charging / discharging control, it is possible to perform charging / discharging in a section including SOC 50% or more, for example, SOC 100% (SOC 0% to 100%) or SOC 50% (SOC 50% It is possible to realize a long battery life of the battery bank.

On the other hand, the second battery bank 25 is charged and discharged in the section including the SOC 50% or more (SOC 50% (SOC 50% to 100%)), but the SOC is 50% As shown in FIG.

For example, in this embodiment, the idle time is controlled to be set to four times in the charge / discharge period.

By performing such control, the power of the system including the first battery bank 23 and the second battery bank 25, while performing the charging and discharging equivalent to SOC 100% (SOC 0% to 100% The overall life of the assist unit 20 can be realized.

5B is supplied to the first battery bank 23 and the second battery bank 25 is supplied with the charge and discharge command Discharging command to the first battery bank 23 and to provide the third charging and discharging command to the second battery bank 25 so as to supply the fourth charging and discharging command to the first battery bank 23, The lifetime of each battery bank and the long service life of the entire power assist unit 20 can be realized.

In the charge / discharge control of the present embodiment, when the first battery bank 23 is driven for charge / discharge, the general control unit 29 charges / discharges at SOC 50% (SOC 0% to 50% Charging and discharging are performed in the SOC 50% (SOC 50% or more and 100% or less) when the second battery bank 25 is charged / discharged, but the present invention is not limited thereto.

For example, when the first battery bank 23 is charged / discharged, the SOC is charged and discharged at Q1% (Q1 = 50, at the same time, SOC 0% to Q1% Even when the SOC is Q2% (Q1 + Q2 = 100, and at the same time, the SOC is in a range between Q1% and Q2% or less) during charging / discharging operation of the first battery bank 23, And the life of the second battery bank 25 and the overall life of the power assist unit 20 can be realized.

While the general control section 29 controls the power assist DC / DC converter 24 to be on-state during the period in which the charge / discharge pattern of Fig. 5A is outputted, the present invention is not limited thereto.

For example, the general control section 29 may turn off the power assist DC / DC converter 24 during the period in which the second battery bank 25 is stopped.

By performing such control, the drive ratio of the power assist DC / DC converter 24 can be reduced, and therefore, the efficiency of the entire power assist unit 20 can be improved.

(Fourth charge / discharge pattern)

Fig. 6 shows a case where the triangular approximation wave is selected as the charge / discharge pattern, and when the collective control section 29 receives the first and second charge / discharge commands shown in Figs. 4B and 4C and the third and fourth charge / Discharge command in combination with the fourth charge / discharge command.

Specifically, in the example of Fig. 6A, the collective control section 29 calculates the triangular wave indicated by the broken line and generates a triangular approximate wave which is a combination of square waves shown by the solid line.

Next, the general control section 29 disassembles the triangular approximation wave to generate a battery control pattern for controlling the first battery bank 23 and the second battery bank 25, And outputs the first battery control signal SC2 shown in FIG. 6B to the first battery bank 23 and the second battery control signal SC3 shown in FIG. 6C to the second battery bank 25. [

The general control section 29 outputs a converter control signal SC4 for on-controlling the power assist DC / DC converter 24 during the period in which the charge / discharge pattern of Fig. 6A is output.

6B and 6C, in the period from T30 to T31 (for example, 10 (min)), the collective control unit 29 outputs the first battery control signal SC2 to the first battery bank 23 Discharge command (command same as the period from T20 to T26) shown in Fig.

The collective control unit 29 gives the second charge / discharge command (command same as the period from T20 to T26) shown in FIG. 4C to the second battery bank 25 by the second battery control signal SC3 .

5B to the first battery bank 23 by the first battery control signal SC2 in a period from T31 to T32 (for example, 10 (min)), (Command same as the period from T20 to T26).

The collective control unit 29 gives the fourth charge / discharge command (command same as the period from T20 to T26) shown in Fig. 5C to the second battery bank 25 by the second battery control signal SC3 .

After T32, the general control section 29 repeatedly performs the control from T30 to T32.

Charging / discharging electric power of the first battery bank 23 and the second battery bank 25 is synthesized by performing the above-described control, so that charge / discharge electric power as shown in FIG. 6A is transmitted to the branch power line L22.

6A is transmitted from the power assist unit 20 to the trunk L12 to generate a power assist based on the comparison result of the first power detection signal SM1 and the profile waveform, Operation is performed.

Thus, the fluctuation of the output power of the natural energy generation system can be absorbed.

In addition, since the first and second battery banks 23 and 25 are charged / discharged by the charge / discharge pattern in which the second charge / discharge pattern and the third charge / discharge pattern are combined, The entire life of the power assist unit 20 including the first battery bank 23 and the second battery bank 25 can be realized in the same manner as when the third charge / discharge pattern is applied.

4B) is given to the first battery bank 23 and the second charge / discharge command (FIG. 4C) is given to the second battery bank 25 at the same time (Fig. 5B) is given to the first battery bank 23 and the fourth charge / discharge command (Fig. 5B) is given to the second battery bank 25 at the same time Discharge instruction is alternately given every one cycle period. However, the present invention is not limited to this.

For example, the fifth charge / discharge command may be continuously provided for a plurality of cycle periods, and then the sixth charge / discharge command may be continuously provided for a plurality of cycle periods, and such control may be alternately repeated.

4C) is given to the first battery bank 23 and the first charge / discharge command (FIG. 4B) is given to the second battery bank 25 at the same time, Discharge command (FIG. 5B) to the first battery bank 23 and the fourth charge / discharge command (FIG. 5C) to the first battery bank 23, For example, the seventh charge / discharge command is continuously given for a plurality of cycle periods, and then the eighth charge / discharge command is continuously given for a plurality of cycle periods And this control can be repeated alternately.

Also, the fifth to eighth charge / discharge commands can be provided in any combination.

In addition, the combination of square waves is not limited to the second to fourth charge / discharge patterns, and triangular approximation waves can be realized by combination of other rectangular waves.

At this time, the collective control unit 29 generates a trigonometric approximate wave so as to set a rest time in at least one of the first battery bank 23 and the second battery bank 25. [

(Fifth charge / discharge pattern)

7 is a diagram showing an example of selecting a triangular wave as a charge / discharge pattern.

Specifically, in the example of Fig. 7A, the collective control section 29 adopts a triangular wave as the charge / discharge pattern in accordance with the first power detection signal SM1, and the maximum value of the charge capacity is 4C, And the charge period (T40 to T43) and the discharge period (T43 to T46) in one cycle period are respectively calculated for 5 min.

Next, the general control section 29 disassembles the triangular wave, generates a first battery control pattern for controlling the first battery bank 23, and a second battery control pattern for controlling the second battery bank 25 do.

Thereafter, the general control section 29 outputs the first battery control signal SC2 (first battery control pattern) shown in Fig. 7B to the first battery bank 23 via the interface section 26, To the second battery bank 25, the second battery control signal SC3 (second battery control pattern) shown in Fig.

The general control section 29 outputs a converter control signal SC4 for on-controlling the power assist DC / DC converter 24 during the period in which the charge / discharge pattern of Fig. 7A is output.

7B and 7C, in the period from T40 to T41 (for example, about 1.9 min), the collective control unit 29 sets the first battery bank 23 to the SOC 75 (SOC 0% to 75%), the SOC is linearly increased from 0% to 75% (see FIG. 7B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 ).

In the period from T41 to T42 (for example, 1.2 minutes), the collective control unit 29 sets a dwell time in the first battery bank 23 by the first battery control signal SC2 ).

In addition, the general control section 29 sets the second battery bank 25 to SOC 100% (SOC 0% to 100% interval) by the second battery control signal SC3 and SOC from 0% To 75%, then linearly increased to 100%, then linearly decreased from 100% to 75%, and then charged down to 0% (see FIG. 7C).

In the period from T42 to T43 (for example, 1.9 min), the collective control unit 29 sets the first battery bank 23 to SOC 75% (SOC 0% to 75 %), At the same time, the SOC is linearly reduced from 75% to 0% (see FIG. 7B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 ).

In the period from T43 to T44 (for example, 1.9 min), the collective control unit 29 sets the first battery bank 23 to SOC 75% (SOC 0% to 75 %), At the same time, the SOC is linearly increased from 0% to 75% (see Fig. 7B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 ).

In the period from T44 to T45 (for example, 1.2 minutes), the collective control unit 29 sets the idle time in the first battery bank 23 by the first battery control signal SC2 ).

The general control section 29 controls the second battery bank 25 so that the SOC is changed from 0% to 100% at the SOC 100% (SOC 0% to 100%) by the second battery control signal SC3 To 75%, then linearly ramped up to 100%, then linearly decreasing from 100% to 75% and discharged down to 0% (see FIG. 7C).

In the period from T45 to T46 (for example, 1.9 min), the collective control unit 29 sets the first battery bank 23 to SOC 75% (SOC 0% to 75 %), At the same time, the SOC decreases linearly from 75% to 0% (see Fig. 7B).

The general control section 29 stops the charging and discharging of the second battery bank 25 and sets the rest time in the second battery bank 25 by the second battery control signal SC3 ).

After T46, the general control section 29 repeats the control from T40 to T46.

By performing the above-described control, the charging and discharging electric power of the first battery bank 23 and the second battery bank 25 is synthesized, and the charging and discharging electric power as shown in Fig. 7A is transmitted to the branch electric power line L22.

7A is transmitted from the power assist unit 20 to the trunk L12 so that the power assist is generated based on the comparison result of the first power detection signal SM1 and the profile waveform, Operation is performed.

Thus, the fluctuation of the output power of the natural energy generation system can be absorbed.

In this power assist operation, the collective control unit 29 performs charge / discharge control so as to provide idle periods for the first battery bank 23 and the second battery bank 25, respectively.

Thus, even when charging / discharging at the high rate shown in Figs. 7A to 7C is performed, it is possible to realize a long life of the battery bank as compared with the case where such control is not performed.

7B and 7C, the respective periods of T40 to T41, T41 to T42, T42 to T44, T44 to T45 and T45 to T46 are arbitrarily changed and the first battery bank 23 and the second battery bank 25 The charge / discharge time and the pause time of the battery can be adjusted.

Even in this case, the life of the first battery bank 23 and the second battery bank 25 and the overall life span of the power assist unit 20 can be realized.

- Modified Example 1 -

8 is a diagram showing a first modification of the wind power generation system and the power assist system according to the first embodiment.

The power assist unit 20 shown in FIG. 8 differs from the power assist unit 20 shown in FIG. 1 in that a DC breaker 27 is provided on the first battery bank 23 side of the power line after branched on the branch power line L22.

The interface unit 26 outputs a circuit breaker control signal SC5 for turning on / off the circuit breaker / conduction of the DC circuit breaker 27 generated in accordance with the collective control signal SC1 from the general control unit 29. [

Specifically, the direct current circuit breaker 27 is configured to be able to change the cutoff / conduction between the branch power line L22 and the first battery bank 23 according to the breaker control signal SC5 from the interface unit 26, And conducts the branch power line L22 and the first battery bank 23 when the first battery bank 23 is charging / discharging.

On the other hand, when the first battery bank 23 stops the charge / discharge operation, the connection between the branch power line L22 and the first battery bank 23 is cut off.

Charge / discharge control of the power assist unit 20 by the collective control unit 29 can be performed in the same manner as in the above-described < charge / discharge control >.

As described above, the charging and discharging of the first battery bank 23 can be performed by the first battery control signal SC2. However, by providing the DC interrupter 27, The propagation of electric power between the branch power line L22 and the first battery bank 23 can be surely blocked when the first battery bank 23 stops the charge / discharge operation.

- Modified Example 2 -

FIG. 9 is a diagram showing a second modification of the wind power generation system and the power assist system according to the first embodiment, and shows an example in which two power assist units are connected to the wind power generation system.

Specifically, the power assist system 2 includes power assist units 20a and 20b connected to the main line L12 of the wind power generation system 10 shown in Fig. 1, and a central control unit 29. Fig.

In other words, two power assist units 20a and 20b are connected in parallel to the main line L12 of the wind power generation system 10. [

Each of the power assist units 20a and 20b has the same configuration as the power assist unit 20 shown in Fig.

The collective control unit 29 receives the first power detection signal SM1 indicating the power status of the trunk L12 and outputs the collective control signal SC1a to the interface unit (not shown) of the power assist unit 20a.

Similarly, the collective control unit 29 outputs the collective control signal SC1b to the interface unit (not shown) of the power assist unit 20b.

Thus, the general control section 29 can control the first battery bank, the power assist DC / DC converter, and the second battery bank (not shown) included in the two power assist units 20a and 20b.

The general control unit 29 receives the first battery monitoring signal SM2a and the second battery monitoring signal SM3a from the power assist unit 20a and receives the first battery monitoring signal SM2b from the power assist unit 20b. And the second battery monitoring signal SM3b.

Thus, the collective control unit 29 collectively controls the battery voltage, charge / discharge current, charge / discharge power, etc. of the first battery bank 23 and the second battery bank 25 of the two power assist units 20a and 20b Can be monitored.

It is also possible to perform control based on each piece of information, for example, charge / discharge information of the first battery bank 23 and the second battery bank 25, operation information of the power storage device, The control performance by the control unit 29 can be improved.

9 shows an example in which two power assist units 20a and 20b are connected in parallel to the trunk L12 of the wind power generation system 10. The trunk L12 of the wind power generation system 10, Three or more power assist units 20 may be connected in parallel.

9, the collective control unit 29 collectively controls the power assist units 20 and controls the first battery bank 23 and the second battery bank 23 of each power assist unit 20, The battery voltage of the second battery bank 25, and the like can be collectively monitored.

- Modified Example 3 -

10 is a view showing a third modification of the wind power generation system and the power assist system according to the first embodiment and shows an example in which the power assist system 2 is applied to the wind power generation system 10 having the induction generator 14 Respectively.

Specifically, in the wind power generation system 10 according to the present modification, the wind turbine 11 as a rotating body rotating with wind, the induction generator 14 connected to the rotary shaft of the wind turbine 11 and driven by the rotating body, And a power conversion section 15 provided in the secondary winding L15 of the induction generator 14. [

Generation power generated by the induction generator 14 is output to the main line L14 and is connected to the system 40 via the transformer 42. [

The power conversion section 15 includes a first power generation system inverter 15a for converting (AC / DC converting) AC power into DC power and a second power generation system inverter 15a for converting the DC power output from the first power generation system inverter 15a into AC power A second power generation system inverter 15b for DC / AC conversion), and a transformer 15c for transforming the alternating-current power output from the second power generation system inverter 15b to be connected to the main line L14.

The power assist system 2 is connected to the power assist L15a connected to the direct current power line L15a between the first power generation system inverter 15a and the second power generation system inverter 15b in the secondary winding L15 of the induction generator 14, Unit 20 and a power control unit 29 for controlling the power assist unit 20 in a coordinated manner.

The configuration of the power assist unit 20 is the same as that of the first embodiment.

The general control unit 29 receives the first power detection signal SM1 indicating the power status of the power line L15a before the power assist system 2 (power assist unit 20) supplies the assist power, And outputs the signal SC1 to the interface unit 26 of the power assist unit 20. [

The power supply assisting operation is performed by the power assist unit 20 so that the second power system inverter 15b and the main line L14 to which the AC power after power conversion by the transformer 15c are transmitted , And monitors whether or not the power state after power assist, that is, whether or not the desired power assist operation is performed.

The concrete control by the general control section 29 is the same as that of the first embodiment.

With such a configuration, even when the induction generator is applied to the wind power generation system, the power assist operation can be realized using the power assist system according to the present invention, and the generated power of the wind power generation system can be stably supplied to the system .

- Fourth Modification -

11 is a view showing a fourth modified example of the wind power generation system and the power assist system according to the first embodiment and shows an example in which the power assist system 2 is applied to the solar power generation system 60 as a natural energy generation system Respectively.

Specifically, the photovoltaic power generation system 60 according to the present modification includes a photovoltaic panel 61 as a power generation device that receives natural light such as sunlight to generate direct current power and outputs it to the main line L61, And a power conversion unit 62 that receives the generated power of the solar panel 61 via the trunk L61 and converts the power to AC power and outputs it to the trunk L62.

The trunk line L62 is connected to the system 40 via the transformer 42. [

The power assist system 2 includes a power control unit 29 for controlling the power assist unit 20 and the power assist unit 20 connected to the main line L61.

The configuration of the power assist unit 20 is the same as that of the first embodiment described above.

The general control section 29 receives the first power detection signal SM1 indicating the power status of the main line L61 before the power assist system 2 (power assist unit 20) supplies the assist power, And outputs the signal SC1 to the interface unit 26 of the power assist unit 20. [

The general control section 29 is configured to perform power assist by the power assist unit 20 and to provide a second power level indicating the power status of the trunk L62 to which the AC power after power conversion by the power conversion section 62 is transmitted. Receives the power detection signal SM4, and monitors the power situation after the power assist, that is, whether or not the desired power assist operation has been performed.

The specific control by the general control section 29 is the same as that of the first embodiment described above.

By employing such a configuration, even when the power assist system according to the present invention is applied to the solar power generation system, the power assist operation can be realized and the generated power of the solar power generation system can be stably supplied to the system .

On the other hand, in the case of the photovoltaic power generation system, the cycle of fluctuation of the output power is longer than that of the wind power generation system, that is, the rate of the charge / discharge cycle required for the power assist system is lower than that of the wind power generation system.

For example, the charge / discharge cycle of a photovoltaic system can be from 10 minutes to several days.

The power assist system 2 according to the present invention can be applied to a power generator of such a low rate charging / discharging cycle, and the battery of the power assist unit and the power assist system can be lengthened.

- Modified Example 5 -

1 shows an example in which one wind power generation system 10 is linked to the system. Even when a plurality of wind power generation systems 10 are connected to the system 40, the power assist system 10 according to the present invention, (2) (power assist unit 20) may be applied.

Specifically, when a plurality of wind turbine generators 10 are connected to the system 40 through the respective transformers 42, the power assist units 40 are connected to the main line L12 of each wind turbine generator 10, (20).

At this time, the general control unit 29 may control all the power assist units 20 to control the whole power control unit 29, and may control the power control units 29, And can be configured to control them individually.

On the other hand, a plurality of power assist units 20a and 20b may be connected to some or all of the plurality of wind power generation systems 10 as shown in the second modification.

&Lt; Embodiment 2 >

- Configuration of the system -

12 is a diagram showing a configuration example of a wind power generation system according to the second embodiment.

The present embodiment is different from the first embodiment in that the power assist unit 20 is connected to the trunk L13 through which the AC power after power conversion by the power converter 13 is transmitted.

The inverter 22 connected to the other end of the circuit breaker 21 via the power line L21 and the inverter 22 are connected to the other end of the circuit breaker 21, A first battery bank 23 as a first power storage device connected to the branch power line L22 and a power assist DC / DC converter 24 connected to the branch power line L22 A second battery bank 25 as a second power storage device connected to the downstream side of the power assist DC / DC converter 24, and an interface unit 26.

The first battery bank 23 is a battery bank configured to be capable of charging / discharging at a high rate, and is composed of, for example, a lithium ion battery.

The terminal voltage of the first battery bank 23 is, for example, 800V.

The second battery bank 25 is a battery bank configured to be capable of charging / discharging at a high rate, and is made of, for example, a lithium ion battery.

The second battery bank 25 is configured such that the terminal voltage is equal to or lower than the terminal voltage of the first battery bank 23.

In other words, for example, when the terminal voltage of the first battery bank 23 is 800 V, the second battery bank 25 is configured to have a terminal voltage of, for example, 3 V or more and 600 V or less .

On the other hand, the terminal voltage of the second battery bank 25 is not limited to 600 V or less.

For example, the terminal voltage of the second battery bank 25 may exceed 600 V. For example, the terminal voltage of the second battery bank 25 and the terminal voltage of the first battery bank 23 may be the same.

The power assist DC / DC converter 24 is connected to the output terminal of the second battery bank 25 and has a function of boosting the output terminal voltage to connect to the branch power line L22. The input voltage range is Is set in a range according to the setting range of the terminal voltage of the second battery bank 25. [

The inverter 22 is connected between the branch power line L22 and the power line L21, and performs DC-AC conversion.

The voltage of the power line L21 is, for example, 380V to 480V.

The circuit breaker 21 is configured to be capable of changing the cutoff / conduction between the main line L13 of the wind power generation system 10 and the power line L21 of the power assist unit 20, The main line L13 and the power line L21 are conducted when the first battery bank 23 and / or the second battery bank 25 is charging / discharging, for example.

On the other hand, when an overcurrent occurs or an abnormality occurs, for example, when an abnormal voltage such as a lightning surge occurs due to a lightning stroke, it is automatically or under control of the general control section 29 (the control signal line is not shown) , And disconnects the connection between the trunk line L13 and the power line L21.

By adopting such a configuration, it is possible to flexibly change the power storage capacity of the second battery bank 25 in the same manner as in the first embodiment, and to automatically charge the first battery bank 23 and the second battery bank 25 At the same time.

As a result, even when a high rate of charge and discharge is performed in the first battery bank 23 and the second battery bank 25 in the power assist operation of the wind power generation system 10, In comparison, it is possible to realize a long battery life.

On the other hand, in the power assist unit 20 of Fig. 12, the circuit breaker 21 has an optional configuration, and the same effect can be obtained even if it is not included in the configuration.

On the other hand, in the wind turbine generator 10, the synchronous generator 12 and the power converter 13 may be integrated with the wind turbine 11 in some cases.

When the power assist unit 20 is mounted on the wind power generation system 10 having such a configuration, by using the same configuration as that of the present embodiment, advantages such as installation work, replacement work, maintenance work, .

The general control section 29 receives the first power detection signal SM1 indicating the power status of the trunk L13 before the assist power is supplied by the power assist system 2 (power assist unit 20) To the interface section 26, a collective control signal SC1 for controlling the battery bank 23, the second battery bank 25, the power assist DC / DC converter 24 and the inverter 22. [

The collective control unit 29 receives the first battery monitoring signal SM2 indicating the battery voltage, the charge / discharge current, and the charge / discharge power from the first battery bank 23, And so on.

Similarly, the general control section 29 receives the second battery monitoring signal SM3 indicating the battery voltage, the charge / discharge current, and the charge / discharge power from the second battery bank 25, And so on.

The general control unit 29 receives the second power detection signal SM4 indicating the power status of the trunk L13 after the power assist unit 20 has performed the power assist, And monitors whether or not a desired power assist operation has been performed.

- Power stabilization control (charge / discharge control) -

As in the first embodiment, the inventors limit the fluctuation range of the power from the wind power generation system 10 to the system 40 to within a predetermined range (for example, within P1 of FIG. 2B) A predetermined pattern charge / discharge instruction based on the relationship is provided from the general control section 29 to the first battery bank 23 and the second battery bank 25. [

Hereinafter, the specific charge / discharge control by the general control section 29 will be described in detail.

<Charge / discharge control>

First, the general control section 29 receives the first power detection signal SM1 and calculates a charge / discharge pattern for stabilizing the output power of the wind power generation system 10 in accordance with the first power detection signal SM1 do.

Specifically, the first power detection signal SM1 is compared with the profile waveform to select a predetermined pattern (waveform shape) to be used for the charge / discharge pattern, and the charge / discharge capacity applied to the charge / discharge pattern, And the like.

The waveform shape selected by the general control section 29 as a predetermined charge / discharge pattern is a case where charging / discharging control based on the DC waveform on the downstream side of the inverter 22 is performed, for example, a square wave, a triangle wave, .

When charging / discharging control based on the AC waveform on the upstream side of the inverter 22 is performed, for example, there is a sinusoidal wave or the like.

(First to fifth charge / discharge patterns)

When a rectangular wave, a triangular wave, or a triangular approximation wave is selected as the charge / discharge pattern based on the DC waveform on the downstream side of the inverter 22, the collective control section 29 sets the "first charge / discharge pattern 1 Quot; fifth charge / discharge pattern &quot; from the &quot; fifth charge / discharge pattern &quot;

Specifically, the collective control section 29 selects a charge / discharge pattern in accordance with the first power detection signal SM1, decomposes the charge / discharge pattern, and generates a first battery control pattern for controlling the first battery bank 23 And a second battery control pattern for controlling the second battery bank 25 are generated.

Thereafter, the collective control unit 29 outputs to the interface unit 26 the collective control signal SC1 to which the information of the first and second battery control patterns and the information of the power converter control pattern are added.

The interface unit 26 outputs the first battery control signal SC2 to the first battery bank 23 as a charge / discharge command generated in accordance with the general control signal SC1 received from the general control unit 29. [

Also, the second battery control signal SC3, which is a charge / discharge command generated in the same manner, is output to the second battery bank 25. [

The interface unit 26 also outputs a converter control signal SC4 which is an on / off control command of the power assist DC / DC converter 24 generated in accordance with the collective control signal SC1 received from the general control unit 29, And outputs it to the DC / DC converter 24.

Similarly, the interface section 26 outputs to the inverter 22 the inverter control signal SC6, which is an on / off control command of the inverter 22 generated in accordance with the collective control signal SC1 received from the collective control section 29 .

An example of a specific charge / discharge pattern is shown in Figs. 3 to 7 already described, and the collective control section 29 can perform the same control as that of the first embodiment.

At this time, in each control of the &quot; fifth charge / discharge pattern &quot; from the &quot; first charge / discharge pattern &quot;, the charge / discharge pattern in Figs. 3A, 4A, 5A, 6A, And outputs an inverter control signal SC6 for turning on the inverter 22 to the inverter 22 when the first battery bank or the second battery bank is in charge / discharge operation.

On the other hand, the general control section 29 controls the inverter 22 to stop (turn off) the inverter 22 when neither the first battery bank 23 nor the second battery bank 25 is performing charge / (SC6) to the inverter (22).

Accordingly, the general control section 29 is provided with the first battery bank 23, the second battery bank 25, the power assist DC / DC converter 24, and the inverter 22 collectively Can be controlled.

When neither the first battery bank 23 nor the second battery bank 25 performs the charging / discharging operation, since the inverter 22 is controlled to be off, the driving rate of the inverter 22 is reduced .

Thus, the efficiency of the entire power assist unit 20 can be improved.

(Sixth charging / discharging pattern)

13 and 14 are diagrams showing examples of selecting a sinusoidal wave as a charge / discharge pattern based on the AC waveform on the upstream side of the inverter 22.

Specifically, the general control section 29 selects a charge / discharge pattern to be applied to the upstream side of the inverter 22 in accordance with the first power detection signal SM1.

13A shows an example in which a sinusoidal wave is selected as the waveform shape and the one cycle period (T10 to T11) of charging and discharging is calculated as 10 minutes.

Thereafter, the general control section 29 controls the first battery bank 23 and the second battery bank 25 so as to be the charge / discharge pattern (sinusoidal wave) calculated by the AC waveform on the upstream side of the inverter 22 (charge / discharge pattern) of the DC that becomes the base.

13B shows an example in which the general control section 29 selects a square wave as a direct current charge / discharge pattern for controlling the first battery bank 23 and the second battery bank 25 and generates a charge / Respectively.

14B shows that the general control section 29 selects a triangular approximation wave as a direct current charge / discharge pattern for controlling the first battery bank 23 and the second battery bank 25 and outputs a triangular wave And a triangular approximation wave (solid line in Fig. 14B) is generated in accordance with the triangle wave.

The control of the first battery bank 23, the second battery bank 25 and the power assist DC / DC converter 24 by the general control section 29 in Figs. 13B to 13D is performed by the control shown in the example of Figs. 3A to 3C .

At this time, since the collective control unit 29 is charging / discharging any one of the first battery bank and the second battery bank, the inverter control signal SC6 for turning on the inverter 22 is supplied to the inverter 22, .

On the other hand, the control of the first battery bank 23, the second battery bank 25 and the power assist DC / DC converter 24 by the general control section 29 in Figs. 14B to 14D is the same as the example of Figs. 4A to 4C This is the same as the control shown.

At this time, since the collective control unit 29 is charging / discharging any one of the first battery bank and the second battery bank, the inverter control signal SC6 for turning on the inverter 22 is supplied to the inverter 22 .

Charge / discharge power of the first battery bank 23 and the second battery bank 25 is synthesized by performing the above-described control, so that charge / discharge power as shown in FIG. 13A or 14A is transmitted to the power line L21 do.

13A or 14A is transmitted from the power assist unit 20 to the trunk L13 and the result of comparison between the first power detection signal SM1 and the profile waveform Based power assist operation is performed.

Thus, the fluctuation of the output power of the natural energy generation system can be absorbed.

In this power assist operation, the collective control unit 29 performs charge / discharge control so as to provide idle periods for the first battery bank 23 and the second battery bank 25, respectively.

Thus, even when charging / discharging at a high rate is performed, it is possible to realize a long life of the battery bank as compared with the case where such control is not performed.

14B to 14D, the unification control section 29 sets the rest time to the first battery bank 23 and, at the same time, performs SOC of 50% or less (SOC 0 % Or more and 50% or less).

(SOC 50% or more) and SOC 50% (SOC 50% or more and 100% or less), for example, SOC 100% The battery life can be prolonged as compared with the case where charge /

On the other hand, the general control section 29 causes the second battery bank 25 to perform charging / discharging at an SOC of 100% (SOC 0% to 100%), but the pause time is set to be longer than the first battery bank 23 It is controlled to install for a long time.

For example, in this embodiment, the downtime is controlled to be four times as large as the charge / discharge period.

By performing such control, the first battery bank 23, the second battery bank 25, and the electric power including these battery banks, while performing charging / discharging of SOC 100% (SOC 0% to 100% The life of the entire assist unit 20 can be prolonged.

On the other hand, the general control section 29 controls the second battery bank 25 so that the downtime is set to be four times in the charge / discharge period. However, the downtime is set longer than the first battery bank 23 The power assist unit 20 can have a longer life span than that of the power assist unit 20 even in such a case.

- Modified Example 1 -

15 is a diagram showing a first modification of the wind power generation system and the power assist system according to the second embodiment.

The power assist unit 20 shown in Fig. 15 differs from the power assist unit 20 shown in Fig. 12 in that the DC breaker 27 is provided on the first battery bank 23 side in the power line after branched in the branch power line L22.

The interface unit 26 outputs a circuit breaker control signal SC5 for on / off-controlling the cut-off / conduction of the direct current circuit breaker 27 generated in accordance with the collective control signal SC1 from the collective control unit 29. [

Specifically, the direct current circuit breaker 27 is configured to be able to change the blocking / conduction between the branch power line L22 and the first battery bank 23 in accordance with the breaker control signal SC5 from the interface unit 26 , And conducts the branch power line (L22) and the first battery bank (23) when the first battery bank (23) is charging / discharging.

On one side, when the first battery bank 23 stops charging / discharging operation, the connection between the branch power line L22 and the first battery bank 23 is cut off.

Charge / discharge control of the power assist unit 20 by the collective control unit 29 can be performed in the same manner as in the above-described < charge / discharge control >.

As described above, the charging and discharging of the first battery bank 23 can be performed by the first battery control signal SC2. However, by providing the DC interrupter 27, The propagation of electric power between the branch power line L22 and the first battery bank 23 can be surely blocked when the first battery bank 23 stops the charge / discharge operation.

- Modified Example 2 -

16 is a diagram showing a second modification of the wind power generation system and the power assist system according to the second embodiment.

The power assist unit 20 of the second modification differs from the configuration of Fig. 12 in that the power assist unit 20 is configured to be directly connectable to the system 40. [

More specifically, the power line L21 of the power assist unit 20 is connected to the system 40 via the circuit breaker 21 and the transformer 47, so that the power assist unit 20 is directly connected to the system 40 Respectively.

In the second modification, the collective control unit 29 is connected to the power conversion unit 13 of the wind power generation system 10 and the first power detection unit 33, which indicates the power status of the trunk L13 connecting between the transformer 42 Signal SM1 and outputs a collective control signal SC1 for controlling the first battery bank 23, the second battery bank 25, the power assist DC / DC converter 24 and the inverter 22 to the interface 26).

The general control unit 29 receives the power control signal from the power line connecting between the power assist unit 20 and the transformer 47 as the power situation after the power assist unit 20 has performed the power assist, (SM4), and monitors the power situation after the power assist, i.e., whether or not the desired power assist operation has been performed.

In the second modification, when the voltage value of the power line L21 of the power assist unit 20 is equal to the voltage value of the system 40, the transformer 47 is omitted and the power assist unit 20 is connected to the system (40).

- Modified Example 3 -

17 is a diagram showing a third modification of the wind power generation system and the power assist system according to the second embodiment.

The power assist unit 20 of the third modification is different from the configuration of Fig. 12 in that the power assist unit 20 is configured to be connectable to the second system 50 different from the system 40. [

Specifically, by connecting the power line L21 of the power assist unit 20 to the second system 50 via the transformer 51, the power assist unit 20 is linked to the second system 50 have.

A breaker 28 is provided between the power line L21 and the transformer 51 and is configured to be able to change the cutoff / conduction of the connection between the power line L21 and the transformer 51. [

The circuit breaker 28 disconnects the power line L21 from the transformer 51 during normal operation.

On the other hand, when an abnormality such as when the supply of power from the wind power generation system 10 to the system 40 is stopped or when the system power supply 41 of the system 40 is lost, 21 is automatically or under the control of the general control unit 29 or the like (the control signal line is not shown) to cut off the connection between the main line L12 and the branch power line L22, and the circuit breaker 28, (The control signal line is not shown) and conducts the power line L21 and the transformer 51 under the control of the inverter 29 and the like.

Thus, during the normal operation, the power assist operation from the power assist system 2 to the wind power generation system 10 is performed, and when the abnormal state occurs, the first battery bank 23 and the second battery bank 25 It is possible to supply power to the second system 50 via at least one of the power line L21 and the transformer 51. [

In other words, it can also be used as an emergency power supply when an abnormal state occurs.

- Fourth Modification -

18 is a view showing a fourth modification of the wind power generation system and the power assist system according to the second embodiment.

The power assist unit 20 of the fourth modification is different from the configuration of Fig. 12 in that the filter circuit 31 is provided on the power line L21 of the power assist unit 20. [

The filter circuit 31 includes an inductor 31a provided between the inverter 22 and the circuit breaker 21 and a capacitor 31b provided between the power line L21 and the ground.

Thus, the assist power of the power assist unit 20 can be smoothed.

On the other hand, if there is no problem even if ripple occurs, for example, if the filter function is owned by another circuit or configuration, or if it is an environment where it is difficult for ripple to occur in the assist power, the filter circuit 31 is excluded from the configuration .

- Modified Example 5 -

19 is a diagram showing a fifth modified example of the wind power generation system and the power assist system according to the second embodiment, and shows an example in which two power assist units are connected to the wind power generation system.

Specifically, the power assist system 2 includes power assist units 20a and 20b connected to the main line L13 of the wind power generation system 10 shown in Fig. 12, and a collective control unit 29. Fig.

In other words, two power assist units 20a and 20b are connected in parallel to the main line L13 of the wind power generation system 10.

Each of the power assist units 20a and 20b has the same configuration as the power assist unit 20 shown in Fig.

The general control section 29 receives the first power detection signal SM1 indicating the power status of the trunk L13 before the power assist system 2 (power assist unit 20) supplies the assist power, And outputs the collective control signal SC1a to the interface unit (not shown) of the unit 20a.

Similarly, the collective control unit 29 outputs the collective control signal SC1b to the interface unit (not shown) of the power assist unit 20b.

Thus, the general control section 29 can control the first battery bank, the power assist DC / DC converter, and the second battery bank (not shown) included in the two power assist units 20a and 20b.

The general control unit 29 receives the first battery monitoring signal SM2a and the second battery monitoring signal SM3a from the power assist unit 20a and receives the first battery monitoring signal SM2b from the power assist unit 20b. And the second battery monitoring signal SM3b.

Thus, the collective control unit 29 collectively controls the battery voltage, charge / discharge current, charge / discharge power, etc. of the first battery bank 23 and the second battery bank 25 of the two power assist units 20a and 20b Can be monitored.

It becomes possible to perform control based on each piece of information, for example, charge / discharge information of the first battery bank 23 and the second battery bank 25, operation information of the power storage device, etc., ) Can be improved.

19 shows an example in which two power assist units 20a and 20b are connected in parallel to the trunk L13 of the wind power generation system 10. The trunk line L13 of the wind power generation system 10, Three or more power assist units 20 may be connected in parallel.

9, the power control unit 29 can collectively control the power assist units 20 and can control the first battery banks 23 of each power assist unit 20 And the battery voltage of the second battery bank 25 can be collectively monitored.

- Sixth Modification -

20 is a view showing a sixth modified example of the wind power generation system and the power assist system according to the second embodiment, in which two wind power generation systems are installed and two power assist units are connected to these Respectively.

Concretely, a plurality of wind power generation systems 10 are connected to the main line L13, and the main line L13 thereof is connected to the system 40 via the transformer 42. [

The power assist system 2 has the same configuration as that of the power assist system 2 shown in Fig. 19 and the collective control section 29 receives the first power detection signal SM1 from each of the plurality of wind power generation systems 10 Which is different from Fig.

Accordingly, the power assist system 2 (power assist unit 20) according to the present invention can be applied even when a plurality of wind power generation systems 10 are connected to the system 40. [

On the other hand, when a plurality of wind turbine generators 10 are connected to the system 40 via the transformer 42, the power assist units 20 (20) are connected to the main line L13 of each wind turbine generator 10, .

At this time, a plurality of power assist units 20a and 20b may be connected to some or all of the plurality of wind power generation systems 10 as shown in Fig. 19 and Fig.

- Seventh Modification -

12, the power assist system 2 is applied to the wind power generation system 10 having the synchronous generator 12. However, the present invention is not limited to this.

As a seventh modification of the wind power generation system and the power assist system according to the second embodiment, the present invention can be applied to a wind power generation system or a solar power generation system having an induction generator, for example.

For example, when the power assist system 2 according to the second embodiment is applied to the wind power generation system 10 having the induction generator 14 shown in Fig. 10 already described, for example, The power assist unit 20 may be connected to the trunk L14 of the system 10. [

In this modification, the unification control unit 29 receives the first power detection signal SM1 (power supply assisting unit 20) indicating the power status of the trunk L14 before the assist power is supplied by the power assist system 2 And outputs the collective control signal SC1 to the interface unit 26 of the power assist unit 20. [

The collective control unit 29 receives the second power detection signal SM4 indicating the power status of the trunk L14 at which the AC power after the power assist operation is performed by the power assist unit 20, Monitors whether or not a power situation, that is, whether or not a desired power assist operation is performed.

The specific control by the general control section 29 is the same as in the second embodiment.

For example, when the power assist system 2 according to the second embodiment is applied to the photovoltaic power generation system 60 shown in Fig. 11 described above, for example, the trunk L62 of the photovoltaic power generation system 60 The power assist unit 20 may be connected.

In this modification, the collective control unit 29 receives the first power detection signal SM1 (power supply assisting unit 20) indicating the power status of the main line L62 before the assist power is supplied by the power assist system 2 And outputs the collective control signal SC1 to the interface unit 26 of the power assist unit 20. [

In addition, the general control section 29 receives the second power detection signal SM4 indicating the power status of the trunk L62, to which the AC power after the power assist operation by the power assist unit 20 is transmitted, I.e., whether or not the desired power assist operation has been performed.

The specific control by the general control section 29 is the same as in the second embodiment.

<Other Embodiments>

While the preferred embodiments of the present invention have been described, various modifications are possible.

For example, each embodiment and its variations can be combined.

Specifically, for example, in the configuration of Fig. 1 of the first embodiment, the branch power line can be connected to another DC system, and the power assist system can be utilized as an emergency power supply or the like when an abnormal state occurs can do.

8, the DC breaker 27 provided on the branch power line L22 may be applied to the power assist unit 20 shown in Figs. 9 to 11, for example.

In the first embodiment, the collective control unit 29 controls the first battery bank 23, the second battery bank 25, and the power assist DC / DC converter 24 through the interface unit 26 The functions of the integrated control unit 29 and the interface unit 26 are integrated and the integrated control unit 29 directly controls the first battery bank 23 and the second battery bank 25, The power assist DC / DC converter 24 may be collectively controlled.

The integrated control unit 29 directly integrates the functions of the first battery bank 23 and the second battery bank 23 25, the power assist DC / DC converter 24, and the inverter 22 in a single operation.

In the above embodiment, the power assist system 2 (power assist unit 20) is applied to the wind power generation system or the solar power generation system. However, the applicable power generation system is not limited thereto.

For example, it is possible to apply the power assist system 2 (power assist unit 20) according to the present invention to a natural energy generation system that supplies generated power generated by natural energy to the system.

For example, in the case where the power assist system 2 (power assist unit 20) according to the present invention is applied to a hydroelectric power generation system or a pumped-water generation system, an aber- .

The other configuration is the same as in Fig.

This makes it possible to absorb fluctuations in the output power of the natural energy generation system even in the hydroelectric power generation system and the pumped-storage power generation system, and at the same time, the life of the first battery bank and the second battery bank, Can be achieved.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are illustrative and explanatory only and are intended to be illustrative of the invention and are not to be construed as limiting the scope of the invention as defined by the appended claims. It is not. Therefore, those skilled in the art will appreciate that various modifications and equivalent embodiments are possible without departing from the scope of the present invention. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: Wind Power System
11: Windmill
12: Synchronous generator
13: Power conversion section
13a: First power generation system inverter
13b: Second power generation system inverter
14: induction generator
15:
15a: First power generation system inverter
15b: Second power generation system inverter
2: Power assist system
20: Power assist unit
22: Inverter
23: first battery bank (first power storage device)
24: Power assisted DC / DC converter
25: Second battery bank (second power storage device)
26:
27: DC breaker
29:
40: System
50: Second line
60: Solar power system
61: Solar panel
62: Power conversion section
L12: Trunk line (DC trunk line)
L13: Trunk line (AC trunk line)
L15: Secondary winding
L15a: Power line (DC power line)
L22: Branch power line
L61: Trunk line (DC trunk line)
SC1: Integrated control signal
SC2: first battery control signal
SC2: Second battery control signal
SC3: Third battery control signal
SC4: Converter control signal
SM1: first power detection signal

Claims (22)

1. A power assist unit configured to be connected to the main line of a natural energy generation system for supplying generated power by natural energy to the system,
A branch power line connected to the main line of the natural energy generation system;
A first power storage device connected to the branch power line;
A power assisted DC / DC converter connected to the branch power line; And
And a second power storage device connected downstream of the power assisted DC / DC converter
Power assist unit. The method according to claim 1,
Wherein the natural energy generation system includes a rotating body rotating due to natural energy, a synchronous generator driven by the rotating body, and a power conversion unit provided between the synchronous generator and the system,
Wherein the power conversion unit includes a first power generation system inverter for AC / DC conversion connected in series and a second power generation system inverter for DC / AC conversion,
Wherein the branch power line is connected to a DC trunk line connecting between the first power system inverter and the second power system inverter
Power assist unit. The method according to claim 1,
The natural energy generation system includes a rotating body rotating due to natural energy, an induction generator driven by the rotor, and a power conversion unit installed in a secondary winding of the induction generator,
Wherein the power conversion unit includes a first power generation system inverter for AC / DC conversion connected in series and a second power generation system inverter for DC / AC conversion,
Wherein the branch power line is connected to a DC power line connecting between the first power system inverter and the second power system inverter
Power assist unit. The method according to claim 1,
The trunk line is an alternating current trunk line,
Further comprising an inverter connected to the AC trunk line,
The branch power line is connected to the downstream side of the inverter,
And is connected to the AC trunk line via the inverter
Power assist unit. The method according to claim 1,
Wherein the output voltage of the first power storage device is higher than the output voltage of the second power storage device
Power assist unit. The method according to claim 1,
And a DC breaker installed in a power line of the first power storage device side of the power line after the branch of the branch power line to electrically disconnect or conduct the first power storage device and the branch power line
Power assist unit. 5. The method of claim 4,
Wherein the inverter is electrically connected to a second system different from the system,
When the power supply from the natural energy generation system to the system is stopped or the power supply to the system side is stopped, the power supply from the first power storage device and the second power storage device Powered by the second system
Power assist unit. The method according to claim 1,
The natural energy generation system
An integrated control unit for outputting an integrated control signal for controlling charge and discharge of the first power storage device and the second power storage device,
Generates a first battery control signal for controlling charging and discharging of the first power storage device according to the collective control signal and outputs the generated first battery control signal to the first power storage device, And an interface unit for generating and outputting a second battery control signal for controlling charging and discharging of the second power storage device to the second power storage device,
A first charge / discharge control which is controlled by the general control section via the interface section, in which one of the first power storage device and the second power storage device is driven to be charged / discharged and at the same time, The second charge / discharge control in which the other device is charged / discharged and the charge / discharge of the device is stopped is alternately selected
Power assist unit. 9. The method of claim 8,
Wherein the general control signal output by the general control section includes a converter control command for on-off controlling the power assisted DC / DC converter,
The interface unit outputs a converter control signal for controlling the power assist DC / DC converter to the power assist DC / DC converter in response to the converter control command
Power assist unit. A power assist unit according to claim 1 and a general control unit for controlling charge and discharge of the first power storage device and the second power storage device,
A first charge / discharge control for driving one of the first power storage device and the second power storage device to charge and discharge while stopping charging / discharging of another device; and a charge / And second charge / discharge control for stopping charging / discharging of the above-mentioned apparatus are performed alternately
Power assist system. 11. The method of claim 10,
The collective control unit
In the first charge / discharge control, the apparatus is charged / discharged so that the SOC is not more than 1% of Q, the charge / discharge of the other apparatus is stopped,
Discharge control so that the other device is charged / discharged so that the SOC is equal to or less than Q2%, the charge / discharge of the device is stopped,
At this time, Q1 = 50 and Q1 < Q2 = 100 are satisfied,
When the time of the second charge / discharge control is shorter than the time of the first charge /
Power assist system. A power assist unit according to claim 4, and a general control section for controlling charging and discharging of the first power storage device and the second power storage device,
A first charge / discharge control for driving one of the first power storage device and the second power storage device to charge and discharge while stopping charging / discharging of another device; and a charge / And second charge / discharge control for stopping charging / discharging of the above-mentioned apparatus are performed alternately
Power assist system. 13. The method of claim 12,
The collective control unit
In the first charge / discharge control, the apparatus is charged / discharged so that the SOC is not more than 1% of Q, the charge / discharge of the other apparatus is stopped,
Discharge control so that the other device is charged / discharged so that the SOC is equal to or less than Q2%, the charge / discharge of the device is stopped,
At this time, Q1 = 50 and Q1 < Q2 = 100 are satisfied,
When the time of the second charge / discharge control is shorter than the time of the first charge /
Power assist system. A power assist unit according to claim 1 and a general control unit for controlling charge and discharge of the first power storage device and the second power storage device,
The collective control unit
Discharging the first power storage device and the second power storage device so that the SOC is less than or equal to 1% Q1 and satisfying Q1 = 50, Wow,
Discharge control so as to satisfy Q1 + Q2 = 100, charge / discharge such that the SOC of the above-described apparatus is Q1% or less, and charge / discharge such that the SOC of the other apparatus is Q1% or more and Q2% or less doing,
Power assist system. A power assist unit according to claim 4, and a general control section for controlling charging and discharging of the first power storage device and the second power storage device,
The collective control unit
Discharging the first power storage device and the second power storage device so that the SOC is less than or equal to 1% Q1 and satisfying Q1 = 50, Wow,
Discharge control so as to satisfy Q1 + Q2 = 100, charge / discharge such that the SOC of the above-described apparatus is Q1% or less, and charge / discharge such that the SOC of the other apparatus is Q1% or more and Q2% or less doing,
Power assist system. 12. The method of claim 11,
The collective control unit
A power monitoring signal indicating a state of the generated power,
Discharge command waveform corresponding to the assist power of the branch power line corresponding to the power supervisory signal so that the charge / discharge waveform of the branch power line becomes the charge / discharge command waveform, 2 charge / discharge control
Power assist system. 17. The method of claim 16,
Wherein the charge control command waveform is a charge / discharge command waveform, wherein the triangular wave based on the combination of the triangular wave and the square wave having the amplitude and the charge / discharge cycle calculated in accordance with the power monitoring signal is used as the first charge / discharge Discharge instruction to be applied to the second charge / discharge control, and to control the first power storage device and the second power storage device
Power assist system. 11. The method of claim 10,
The collective control unit
A charge / discharge command waveform of the triangular wave corresponding to the assist power of the branch power line is calculated in accordance with the power monitor signal,
A first charge / discharge instruction to apply the triangular wave to the first charge / discharge control, and a second charge / discharge instruction to apply to the second charge / discharge control,
The first power storage device and the second power storage device
Power assist system. 13. The method of claim 12,
The collective control unit
A power monitoring signal indicating a state of the generated power,
A charge / discharge command waveform corresponding to an assist power of a power line between the inverter and the AC main line in accordance with the power monitoring signal,
The first charge / discharge control and the second charge / discharge control are performed so that the charge / discharge waveform of the branch power line becomes the calculated charge / discharge waveform
Power assist system. 11. The method of claim 10,
The collective control unit
A third charge / discharge control for charging / discharging the first power storage device and the second power storage device so that the SOC of the first power storage device and the second power storage device is Q1%
A fourth charge / discharge control is performed in which Q1 + Q2 = 100, the charge / discharge is performed so that the SOC of the above-described device is not more than Q1%, and at the same time the SOC of the other device is Q1%
Discharge control by combining the first charge-discharge control and the second charge-discharge control, and the sixth charge-discharge control by combining the third charge-discharge control and the fourth charge- To &lt; RTI ID = 0.0 &gt;
Power assist system. 13. The method of claim 12,
The collective control unit
Off control of the driving and stopping of the power assist DC / DC converter,
Wherein the power assist DC / DC converter is driven when the charge / discharge operation of the second power storage device is driven,
And stops the power assist DC / DC converter when the charge / discharge operation of the second power storage device is stopped
Power assist system. 13. The method of claim 12,
The collective control unit
Off control of driving and stopping of the inverter,
The inverter drives the charge / discharge operation of the first power storage device or the second power storage device,
Wherein when the first power storage device and the second power storage device do not drive the charge / discharge operation, the inverter is stopped
Power assist system.

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