JP6799502B2 - Power conversion device for photovoltaic power generation and control method of power converter for photovoltaic power generation - Google Patents

Description

The present invention relates to a power converter for photovoltaic power generation and a control method thereof, and more particularly to a technique effective for stabilizing a power supply by photovoltaic power generation.

The power conversion device for photovoltaic power generation is a power conversion device that converts DC power generated by a solar panel into AC power and supplies power to the power system.

As an example of a power conversion device for photovoltaic power generation, there is one composed of a chopper and an inverter. In this method, the DC power output by the solar panel is boosted by the chopper, and the DC power output by the chopper is converted into AC power of a commercial frequency by the inverter and transmitted to the power system.

In such a power conversion device for photovoltaic power generation, maximum power point tracking (MPPT) control is generally performed so that the output power of the solar panel is maximized. The maximum power point tracking control is a control that adjusts the panel voltage of the solar panel so that the output power of the solar panel is maximized by following the output characteristics of the solar panel that change depending on the surrounding environment. Such maximum power point tracking control is performed by the chopper adjusting the panel voltage of the solar panel.

On the other hand, electricity needs to always balance supply and demand. If the supply is too large for the demand for electric power, there is a risk that the stable supply of electric power will be hindered, such as a power outage. In order to avoid such a situation, in the power conversion device for photovoltaic power generation, it is required to control the output power of the solar panel according to the output command from the electric power company.

As a background technology in this technical field, for example, there is a technology such as Patent Document 1. Patent Document 1 describes "a power conversion device for photovoltaic power generation that stops the maximum power point tracking control and suppresses the output power in accordance with the output power suppression command when the output power suppression is required".

Japanese Unexamined Patent Publication No. 2013-183578

However, when the maximum power point tracking control is stopped and the output power is suppressed in accordance with the output power suppression command, the output power suppression may not be achieved depending on the output characteristics of the solar panel.

For example, if a part of the solar panel is shaded by the influence of clouds or the like, the output characteristics of the solar panel may change significantly. Due to the generation of partial shadows on the solar panel, the solar panel does not have the convex output characteristic of having one maximum value, but has the output characteristic of having a plurality of maximum values.

In a photovoltaic power conversion device connected to such a solar panel, when the maximum power point tracking control is stopped and the panel voltage is increased in order to reduce the output power, as in Patent Document 1, the output is output. Even though the power suppression command has been issued, there will be a situation where the output power turns to an upward trend.

In addition, since the shadow cast on the solar panel changes from moment to moment, the output characteristics of the solar panel also change with time, and the output power of the photovoltaic power conversion device also changes accordingly.

Therefore, an object of the present invention is to provide a photovoltaic power conversion device capable of controlling output power with high accuracy in response to an output power suppression command and a control method thereof in photovoltaic power generation.

In order to solve the above problems, the present invention is a power conversion device for solar power generation that converts DC power output from a solar panel into AC power and outputs it to a system, and is output from the solar panel. A chopper that boosts DC power, an inverter that converts DC power output from the chopper into AC power, and a control unit that controls the operation of the chopper and the inverter. The control unit includes the chopper and the chopper. A first DC voltage control unit that controls the DC voltage of the DC circuit that connects the inverter, an active power control unit that controls the output power of the inverter, and the active power control unit that receives an output suppression command from the outside. have a, and output suppression control unit that outputs an output power command to the control unit includes a panel voltage monitoring unit that monitors the panel voltage of the solar panel, the panel voltage monitoring unit, the solar panel It is characterized in that the output power of the power conversion device for solar power generation is suppressed when the panel voltage of the above is lowered .

Further, the present invention is a control method of a power conversion device for solar power generation that converts DC power output from a solar panel into AC power and outputs it to a system, and outputs the solar panel in a steady state. The maximum power point tracking control for controlling the panel voltage of the solar panel is performed by the chopper based on the voltage detection value of the voltage and the current detection value of the output current, and the inverter uses the DC voltage detection value on the input side of the inverter. When DC voltage control is performed to control the DC voltage of the DC circuit connecting the chopper and the inverter and an output suppression command is input to the power converter for solar power generation, the chopper connects the chopper and the inverter. When the DC voltage control that controls the DC voltage of the DC circuit is performed, the control method is switched so that the inverter performs the active power control that controls the output power of the inverter, and the panel voltage of the solar panel drops. The output power correction command is output to the chopper and the inverter to suppress the output power of the solar power conversion device .

According to the present invention, in photovoltaic power generation, it is possible to realize a photovoltaic power generation power conversion device capable of controlling output power with high accuracy in response to an output power suppression command and a control method thereof.

Issues, configurations and effects other than those described above will be clarified by the description of the following embodiments.

It is a figure which shows the structure of the electric power conversion apparatus for photovoltaic power generation which concerns on one Embodiment of this invention. It is a figure which shows the characteristic of the solar panel which concerns on one Embodiment of this invention. It is a figure which shows the operation of the electric power conversion apparatus for photovoltaic power generation which concerns on one Embodiment of this invention. It is a figure which shows the structure of the chopper which concerns on one Embodiment of this invention. It is a figure which shows the structure of the electric power conversion apparatus for photovoltaic power generation which concerns on one Embodiment of this invention. It is a figure which shows the characteristic of the solar panel which concerns on one Embodiment of this invention. It is a figure which shows the operation of the electric power conversion apparatus for photovoltaic power generation which concerns on one Embodiment of this invention. It is a figure which shows the structure of the electric power conversion apparatus for photovoltaic power generation which concerns on one Embodiment of this invention. It is a figure which shows the structure of the electric power conversion apparatus for photovoltaic power generation which concerns on one Embodiment of this invention.

Hereinafter, the photovoltaic power conversion device according to the present invention and examples thereof will be described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals, and the detailed description of overlapping portions will be omitted.

The power conversion device for photovoltaic power generation and its control method according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 4. FIG. 1 is a block diagram showing an outline of the configuration of the power conversion device for photovoltaic power generation of this embodiment.

As shown in FIG. 1, the power conversion device 1 for photovoltaic power generation of the present embodiment has a voltage detector 2, a current detector 3, a chopper 4, a voltage detector 5, an inverter 6, and a voltage detector as main configurations. 7. It has a current detector 8 and a control unit 9.

The solar panel 10 is connected to the input side of the chopper 4, the output side of the chopper 4 is connected to the DC part (input side) of the inverter 6, and the AC part (output side) of the inverter 6 is connected to the three-phase power system 11. It is connected. The chopper 4 boosts the DC power supplied from the solar panel 10 and supplies it to the inverter 6. The inverter 6 converts the DC power supplied from the chopper 4 into AC power and supplies it to the power system 11.

The voltage detector 2 is provided on the output side of the solar panel 10 and detects the output voltage of the solar panel 10. The output voltage of the solar panel 10 is the same as the DC voltage on the input side of the chopper 4, and the voltage detector 2 can also detect the DC voltage on the input side of the chopper 4. The current detector 3 is provided on the output side of the solar panel 10 and detects the output current of the solar panel 10. The output current of the solar panel 10 is the same as the input current to the input side of the chopper 4, and it can be said that the input current to the input side of the chopper 4 is detected.

The voltage detector 5 is provided on the output side of the chopper 4 and detects the DC voltage on the output side of the chopper 4. The DC voltage on the output side of the chopper 4 is the same as the DC voltage of the inverter 6, and it can be said that the DC voltage of the inverter 6 is detected.

The voltage detector 7 is provided on the output side of the inverter 6 and detects the system voltage of the system to which the inverter 6 is connected. The current detector 8 is provided on the output side of the inverter 6 and detects the output current output to the system to which the inverter 6 is connected.

The voltage detection value and the current detection value detected by the voltage detector 2, the current detector 3, the voltage detector 5, the voltage detector 7, and the current detector 8 are input to the control unit 9. Further, an external command is input to the control unit 9. This external command is an output suppression command input when the output power of the photovoltaic power generation conversion device 1 is suppressed (controlled).

The control unit 9 performs a predetermined calculation based on the input voltage detection value, current detection value, and external command, and outputs a gate pulse signal for driving the chopper 4 and the inverter 6.

As shown in FIG. 1, the control unit 9 has an external command receiving unit 12, an output suppression control unit 13, an active power control unit 14, a DC voltage control unit 17, a current control unit 18, and a PWM control unit 19 as main configurations. It has a maximum power point tracking control unit 20, a DC voltage control unit 21, a PWM control unit 22, and changeover switches 15 and 16.

The external command receiving unit 12 receives the external command and outputs the output suppression command to the output suppression control unit 13. The output suppression control unit 13 receives the output suppression command output by the external command reception unit 12, and outputs an output power command to the active power control unit 14 and a changeover command to the changeover switch 15 and the changeover switch 16.

The active power control unit 14 inputs the voltage detection value and the current detection value on the output side of the inverter 6 and the output power command output by the output suppression control unit 13, and the output power output by the inverter 6 to the power system 11 is the output power command. The active power control is performed so as to match with, and the output current command to the inverter 6 is output.

The DC voltage control unit 17 takes the DC voltage detection value of the DC unit (input side) of the inverter 6 as an input, and performs DC voltage control so that the DC voltage of the DC unit (input side) of the inverter 6 becomes constant. Output the output current command to 6.

The changeover switch 15 receives the output current command output by the active power control unit 14, the output current command output by the DC voltage control unit 17, and the changeover command output by the output suppression control unit 13 as inputs, and the power conversion device 1 for solar power generation. When suppressing the output power of, the output current command output by the active power control unit 14 is selected and output, and at other times, the output current command output by the DC voltage control unit 17 is selected and output.

The current control unit 18 inputs the output current command output by the changeover switch 15, the voltage detection value of the system voltage of the power system 11, and the current detection value of the output current flowing from the inverter 6 to the power system 11, and the inverter 6 to the power system 11 The current is controlled so that the output current flowing to the current matches the output current command, and the output voltage command of the inverter 6 is output.

The PWM control unit 19 receives the output voltage command output by the current control unit 18 as an input, performs PWM (Pulse Width Modulation) control, and outputs a gate pulse signal for driving the inverter 6.

The maximum power point tracking control unit 20 receives the voltage detection value of the output voltage of the solar panel 10 and the current detection value of the output current as inputs, and performs maximum power point tracking control so that the output power of the solar panel 10 is maximized. By doing so, the output voltage command of the solar panel 10 is calculated, DC voltage control is performed so that the output voltage of the solar panel 10 matches the output voltage command, and the output voltage command to the chopper 4 is output.

The DC voltage control unit 21 takes the DC voltage detection value on the output side of the chopper 4 as an input, performs DC voltage control so that the DC voltage on the output side of the chopper 4 becomes constant, and outputs an output voltage command to the chopper 4. To do. Although not shown, the DC voltage control unit 21 may be configured to take in the current on the input side or the current on the output side of the chopper 4 to perform current control.

The changeover switch 16 receives the output voltage command output by the maximum power point tracking control unit 20, the output voltage command output by the DC voltage control unit 21, and the changeover command output by the output suppression control unit 13 as inputs, and power conversion for solar power generation. When suppressing the output power of the device 1, the output voltage command output by the DC voltage control unit 21 is selected and output, and in other cases, the output voltage command output by the maximum power point tracking control unit 20 is selected and output. Output.

The PWM control unit 22 receives the output voltage command output by the changeover switch 16 as an input, performs PWM (Pulse Width Modulation) control, and outputs a gate pulse signal for driving the chopper 4.

FIG. 2 shows an example of panel characteristics when the solar panel 10 is partially shaded. In FIG. 2, the operating point S is an operating point when the photovoltaic power generation power conversion device 1 is performing maximum power point tracking control. FIG. 3 shows an operation waveform when an output suppression command is given from the outside to shift the operating point to the operating point G and suppress the output power while operating at the operating point S. Further, FIG. 4 shows the configuration of the chopper 4. The main circuit of the chopper 4 is composed of a capacitor 41, a reactor 42, a switching element 43 such as an IGBT, and a diode 44.

In FIG. 3, from time 0 to time T _S , the chopper 4 performs maximum power point tracking control, and operates according to an output voltage command output by the maximum power point tracking control unit 20. Further, the inverter 6 controls the DC voltage and operates according to the output current command output by the DC voltage control unit 17.

When the output suppression operation is started from the time T _S , the chopper 4 starts the DC voltage control on the output side and operates according to the output voltage command output by the DC voltage control 21. Further, the inverter 6 starts active power control according to the output power command output by the output suppression control unit 13, and operates according to the output current command output by the active power control unit 14. Therefore, when the output power command output by the output suppression control unit 13 is reduced, the output power of the inverter 6 is reduced according to the output power command.

Since the chopper 4 performs DC voltage control so that the DC voltage on the output side becomes constant, the output power of the inverter 6 and the output power of the chopper 4 are almost the same, and when the output power of the inverter 6 is reduced, the chopper 4 The output power of the inverter is reduced as well. When the output power of the chopper 4 is reduced, the difference power between the output power of the solar panel 10 and the output power of the chopper 4 is stored in the capacitor 41 of the chopper 4 shown in FIG. 4, so that the DC voltage on the input side of the chopper 4, that is, The output voltage of the solar panel 10 rises. When the output voltage of the solar panel 10 increases, the output power of the solar panel 10 decreases, and the output voltage of the solar panel 10 increases until the output power of the inverter 6 and the output power of the solar panel 10 become equal.

Therefore, when the output power command is reduced from P _S to P P ₁ from time T _S to time T _{P 1} , the output power of the inverter 6 and the output power of the solar panel 10 are reduced from P _S to P P ₁ , and the solar power is reduced. The output voltage of the panel 10 rises from V _S to V _{P 1} . At this time, the operating point shifts from the operating point S to the operating point P1 in FIG.

Next, when the output power command is reduced from P _P1 to P _P3 from time T _P1 to time T _P3 , the output power of the inverter 6 is reduced from P _P1 to P _P3 according to the output power command. On the other hand, the output power of the solar panel 10 transiently rises from P _P1 to P _P2 and then decreases to P _P3 . This is because, as shown in FIG. 2, the output characteristic of the solar panel 10 is a local maximum point at the operating point P2. The output voltage of the solar panel 10 rises from V _P1 to V _P3 via V _P2 . At this time, in FIG. 2, the operating point shifts from the operating point P1 to the operating point P3 via the operating point P2. Although not shown, the output current of the solar panel 10 also transiently increases and then decreases.

Next, when the output power command is reduced from P P ₃ to P _G from time T _{P 3} to time T _G , the output power of the inverter 6 and the output power of the solar panel 10 are changed from P P ₃ to P _G according to the output power command. As it decreases, the output voltage of the solar panel 10 rises from V _P3 to V _G. At this time, in FIG. 2, the operating point shifts from the operating point P3 to the operating point PG.

After time T _G, the chopper 4 is operated according to the output voltage command output by the maximum power point tracking control unit 20, and the inverter 6 is operated according to the output current command output by the DC voltage control unit 17. However, the output voltage command output from the maximum power point tracking unit 20 at this time is, the output voltage of the solar panel 10 is controlled to maintain at V _G. By this control, it is possible to maintain the output power of the inverter 6 at P _G.

As described above, according to the power conversion device for solar power generation and its control method of the present embodiment, the chopper 4 is on the output side of the chopper 4 from the maximum power point tracking control that controls the output voltage of the solar panel 10. By switching the control method to DC voltage control that controls the DC voltage of the inverter 6 and switching the control method from DC voltage control that controls the DC voltage of the inverter 6 to active power control that controls the output power of the inverter 6 It becomes possible to follow the output suppression command from.

After that, the chopper 4 controls the output voltage of the solar panel 10 again, and the inverter 6 controls the DC voltage of the inverter 6, so that the output power can be maintained in a suppressed state.

The power conversion device for photovoltaic power generation and the control method thereof according to the second embodiment of the present invention will be described with reference to FIGS. 5 to 7. FIG. 5 is a block diagram showing a configuration outline of the power conversion device for photovoltaic power generation of this embodiment.

In the photovoltaic power conversion device 23 of the present embodiment, as shown in FIG. 5, the control unit 24 takes the output voltage of the solar panel 10 output by the voltage detector 2 as an input and outputs it to the output suppression control unit 26. The point that the panel voltage monitoring unit 25 for outputting the power correction command is provided is different from the first embodiment.

The panel voltage monitoring unit 25 prevents a decrease in the output voltage of the solar panel 10 when the amount of solar radiation decreases during the output suppression operation in the photovoltaic power generation power conversion device 23. When the amount of solar radiation decreases, the maximum power that can be output by the solar panel 10 decreases. Therefore, if the chopper 4 and the inverter 6 try to output more power than the maximum power that can be output by the solar panel 10, the insufficient power is shown. Since the energy stored in the capacitor 41 of the chopper 4 shown in 4 is supplemented, the DC voltage on the input side of the chopper 4, that is, the output voltage of the solar panel 10 decreases.

Therefore, the panel voltage monitoring unit 25 monitors the output voltage of the solar panel 10, and when the output voltage of the solar panel 10 falls below a predetermined value, outputs an output power correction command to the output suppression control unit 26. The output power of the chopper 4 and the inverter 6 is reduced.

FIG. 6 shows an example of panel characteristics when the amount of solar radiation to the solar panel 10 changes. In FIG. 6, the operating point S is an operating point when the maximum power point tracking control is performed when the amount of solar radiation is large. When shifting the operating point from the operating point S to the operating point G to suppress the output power, it becomes impossible to shift to the operating point G due to the decrease in the amount of solar radiation, and instead, when shifting to the operating point G2. The operating waveform of is shown in FIG.

In FIG. 7, the maximum power point tracking control is performed from time 0 to time T _{S, the} chopper 4 operates according to the output voltage command output by the maximum power point tracking control unit 20, and the DC voltage control unit 17 outputs the output. The inverter 6 is operating according to the output current command. When the output suppression operation is started from time T _{S, the} chopper 4 operates according to the output voltage command output by the DC voltage control unit 21, and the active power control unit 14 controls the active power according to the output power command output by the output suppression control unit 26. Is carried out, and the inverter 6 is operated according to the output current command output by the active power control unit 14.

Therefore, when the output power command output by the output suppression control unit 26 is reduced, the output power of the inverter 6 is reduced according to the output power command. Since the chopper 4 performs DC voltage control so that the DC voltage on the output side becomes constant, the output power of the inverter 6 and the output power of the chopper 4 are almost the same, and when the output power of the inverter 6 is reduced, the chopper 4 The output power of the inverter is reduced as well. When the output power of the chopper 4 is reduced, the difference power between the output power of the solar panel 10 and the output power of the chopper 4 is stored in the capacitor 41 of the chopper 4 shown in FIG. 4, so that the DC voltage on the input side of the chopper 4, that is, The output voltage of the solar panel 10 rises. When the output voltage of the solar panel 10 increases, the output power of the solar panel 10 decreases, and the output voltage of the solar panel 10 increases until the output power of the inverter 6 and the output power of the solar panel 10 become equal.

Next, when the amount of solar radiation decreases at time T _{D and} the output power of the solar panel 10 decreases, the difference power between the output power of the solar panel 10 and the output power of the inverter 6 is the capacitor 41 of the chopper 4 shown in FIG. The DC voltage on the input side of the chopper 4, that is, the output voltage of the solar panel 10 is lowered by being supplemented from the energy stored in the inverter.

Next, when the output voltage of the solar panel 10 drops below the predetermined value V _{L at} the time T _L , the panel voltage monitoring unit 25 outputs an output power correction command to the output suppression control unit 26. When the output suppression control unit 26 receives the output power correction command output by the panel voltage monitoring unit 25, the output power command output to the active power control unit 14 is reduced until the decrease in the output voltage of the solar panel 10 is settled.

Next, at time _TM , when the decrease in the output voltage of the solar panel 10 subsides, the chopper 4 is operated again according to the output voltage command output by the maximum power point tracking control unit 20, and the DC voltage control unit 17 outputs the output. The inverter 6 is operated again according to the output current command. At this time, the maximum power point tracking control unit 20 maintains the output voltage of the solar panel 10 at _VG2 . By controlling in this way, the output power of the inverter 6 can be maintained by the P _{G 2} .

As described above, according to the power conversion device for solar power generation and its control method of the present embodiment, the chopper 4 is on the output side of the chopper 4 from the maximum power point tracking control that controls the output voltage of the solar panel 10. By switching the control method to DC voltage control that controls the DC voltage of the inverter 6 and switching the control method from DC voltage control that controls the DC voltage of the inverter 6 to active power control that controls the output power of the inverter 6 It becomes possible to follow the output suppression command from.

Further, even when the amount of solar radiation is reduced during the active power control operation, the panel voltage monitoring unit 25 that monitors the output voltage of the solar panel 10 outputs an output power correction command to output the output voltage of the solar panel 10. It is possible to suppress the decrease in the voltage and continue the operation.

The power conversion device for photovoltaic power generation and its control method according to the third embodiment of the present invention will be described with reference to FIG. FIG. 8 is a block diagram showing a configuration outline of the power conversion device for photovoltaic power generation of this embodiment.

As shown in FIG. 8, in the power conversion device 27 for photovoltaic power generation of this embodiment, as shown in FIG. 8, the solar radiation amount detection unit 29 in which the control unit 28 detects the solar radiation amount and the solar radiation amount detection value output by the solar radiation amount detection unit 29 are obtained. The difference from the first embodiment is that the output suppression control unit 26 is provided with an insolation amount monitoring unit 30 that outputs an output power correction command as an input.

The solar radiation monitoring unit 30 prevents a decrease in the output voltage of the solar panel 10 when the solar radiation amount decreases during the output suppression operation. When the amount of solar radiation decreases, the maximum power that can be output by the solar panel 10 decreases. Therefore, if the chopper 4 and the inverter 6 try to output more power than the maximum power that can be output by the solar panel 10, the insufficient power is shown. Since the energy stored in the capacitor 41 of the chopper 4 shown in 4 is supplemented, the DC voltage on the input side of the chopper 4, that is, the output voltage of the solar panel 10 decreases.

Therefore, the solar radiation amount monitoring unit 30 monitors the solar radiation amount detection value output by the solar radiation amount detection unit 29, and when the solar radiation amount decreases, outputs an output power correction command to the output suppression control unit 26 to cause the inverter 6 to output the output power correction command. Try to reduce the output power.

As described above, according to the photovoltaic power conversion device and its control method of the present embodiment, the solar radiation amount is monitored even when the solar radiation amount is reduced during the active power control operation. It is possible to suppress the decrease in the output voltage of the solar panel 10 and continue the operation as in the above embodiment.

The power conversion device for photovoltaic power generation and the control method thereof according to the fourth embodiment of the present invention will be described with reference to FIG. FIG. 9 is a block diagram showing a configuration outline of the power conversion device for photovoltaic power generation of this embodiment.

In the power conversion device 31 for solar power generation of this embodiment, as shown in FIG. 9, the voltage detection value output by the voltage detector 2 in which the control unit 32 detects the output voltage of the solar panel 10, the solar panel 10 The current detection value output by the current detector 3 that detects the output current of, the voltage detection value output by the voltage detector 5 that detects the DC voltage of the inverter 6, and the voltage that detects the system voltage of the system to which the inverter 6 is connected. Output evaluation unit 33 that receives the voltage detection value output by the detector 7 and the current detection value output by the current detector 8 that detects the output current output to the system connected to the inverter 6 as inputs, and further outputs the evaluation data. Further, the point that the data transmission unit 34 is provided to transmit the evaluation data to the outside by using the evaluation data output by the output evaluation unit 33 as an input is different from the first embodiment.

The output evaluation unit 33 calculates (calculates) and outputs evaluation data indicating the operating state such as the output power and efficiency of each part of the photovoltaic power conversion device 31 from the input voltage detection value and current detection value, and outputs the data. The transmission unit 34 transmits the evaluation data to the outside.

This makes it possible to output the operating state of the photovoltaic power generation power conversion device 31 to the outside, and for example, it is possible to confirm that the photovoltaic power generation power conversion device 31 is operating in accordance with an external command.

In each of the above embodiments, the external command is simply used as time information, the schedule of the output suppression command is registered in advance in the external command receiving unit 12, and the external command receiving unit 12 receives the output suppression command according to the schedule. It may be configured to output.

Further, transmission of an external command (output suppression command) from the outside to the external command receiving unit 12 and transmission of evaluation data from the data transmitting unit 34 to the outside are performed in the installation environment of the solar panel and the power conversion device for photovoltaic power generation. Depending on the method, either wired communication or wireless communication may be used.

In addition to confirming the system configuration and device configuration of the photovoltaic power conversion device, the confirmation of whether or not the photovoltaic power generation power conversion device and its control method are implemented described in each embodiment is performed, for example, in the figure. It can also be judged from the waveform of the panel output as shown in 3 and 7.

Further, the present invention is not limited to the above-described examples, and includes various modifications. For example, the above-described embodiment has been described in detail in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to those having all the described configurations. Further, it is possible to replace a part of the configuration of one embodiment with the configuration of another embodiment, and it is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add / delete / replace a part of the configuration of each embodiment with another configuration.

1 ... Power converter for solar power generation 2 ... Voltage detector 3 ... Current detector 4 ... Chopper 5 ... Voltage detector 6 ... Inverter 7 ... Voltage detector 8 ... Current detector 9 ... Control unit 10 ... Solar panel 11 … Power system 12… External command receiver 13… Output suppression control unit 14… Active power control unit 15… Changeover switch 16… Changeover switch 17… (Second) DC voltage control unit 18… Current control unit 19… PWM control unit 20 ... Maximum power point tracking control unit 21 ... (1st) DC voltage control unit 22 ... PWM control unit 23 ... Solar power conversion device 24 ... Control unit 25 ... Panel voltage monitoring unit 26 ... Output suppression control unit 27 … Solar power conversion device 28… Control unit 29… Solar radiation amount detection unit 30… Solar radiation amount monitoring unit 31… Solar power conversion device 32… Control unit 33… Output evaluation unit 34… Data transmission unit 41… Condenser 42 ... Reactor 43 ... Switching element 44 ... Diode.

Claims (11)

It is a photovoltaic power converter that converts DC power output from a solar panel into AC power and outputs it to the grid.
A chopper that boosts the DC power output from the solar panel,
An inverter that converts DC power output from the chopper into AC power,
A control unit that controls the operation of the chopper and the inverter.
The control unit includes a first DC voltage control unit that controls the DC voltage of the DC circuit connecting the chopper and the inverter.
An active power control unit that controls the output power of the inverter,
Possess an output suppression control section which receives the output suppression instruction from the outside and outputs an output power command to said active power control portion,
The control unit includes a panel voltage monitoring unit that monitors the panel voltage of the solar panel.
The panel voltage monitoring unit is a photovoltaic power conversion device, characterized in that the output power of the photovoltaic power conversion device is suppressed when the panel voltage of the solar panel drops . It is a photovoltaic power converter that converts DC power output from a solar panel into AC power and outputs it to the grid.
A chopper that boosts the DC power output from the solar panel,
An inverter that converts DC power output from the chopper into AC power,
A control unit that controls the operation of the chopper and the inverter.
The control unit includes a first DC voltage control unit that controls the DC voltage of the DC circuit connecting the chopper and the inverter.
An active power control unit that controls the output power of the inverter,
It has an output suppression control unit that receives an output suppression command from the outside and outputs an output power command to the active power control unit.
The control unit includes a solar radiation amount detection unit that detects the amount of solar radiation to the solar panel, and a solar radiation amount detection unit.
It is provided with a solar radiation amount monitoring unit that outputs an output power correction command to the output suppression control unit based on the solar radiation amount detection value of the solar radiation amount detection unit.
A photovoltaic power conversion device, characterized in that the output power of the photovoltaic power conversion device is suppressed when the amount of solar radiation to the solar panel decreases. It is a photovoltaic power converter that converts DC power output from a solar panel into AC power and outputs it to the grid.
A chopper that boosts the DC power output from the solar panel,
An inverter that converts DC power output from the chopper into AC power,
A control unit that controls the operation of the chopper and the inverter.
The control unit includes a first DC voltage control unit that controls the DC voltage of the DC circuit connecting the chopper and the inverter.
An active power control unit that controls the output power of the inverter,
It has an output suppression control unit that receives an output suppression command from the outside and outputs an output power command to the active power control unit.
The chopper has a capacitor
When an output suppression command is input to the control unit, the panel of the solar panel is charged / discharged by charging / discharging the difference power between the output power of the solar panel and the output power of the chopper or the inverter to the capacitor. A power conversion device for photovoltaic power generation, which is characterized by raising a voltage. The power conversion device for photovoltaic power generation according to any one of claims 1 to 3 .
The control unit includes a maximum power point tracking control unit that controls the panel voltage of the solar panel.
A second DC voltage control unit for controlling the DC voltage of the DC circuit connecting the chopper and the inverter is provided.
At regular times, the chopper controls the panel voltage of the solar panel based on the output voltage command of the maximum power point tracking control unit, and the inverter controls the panel voltage of the solar panel based on the output current command of the second DC voltage control unit. Controls the DC voltage of the DC circuit that connects the inverter and
When an output suppression command is input to the control unit, the chopper controls the DC voltage of the DC circuit connecting the chopper and the inverter based on the output voltage command of the first DC voltage control unit, and the inverter controls the DC voltage of the DC circuit connecting the chopper and the inverter. A power conversion device for solar power generation, characterized in that the output power of the inverter is controlled based on the output current command of the active power control unit. The power conversion device for photovoltaic power generation according to any one of claims 1 to 4 .
The control unit includes an output evaluation unit that calculates evaluation data indicating an operating state of the photovoltaic power conversion device.
A power conversion device for photovoltaic power generation, which comprises a data transmission unit that outputs evaluation data of the output evaluation unit to the outside. The power conversion device for photovoltaic power generation according to any one of claims 1 to 5.
When an output suppression command is input to the control unit, the control unit raises the panel voltage of the solar panel until the output power of the solar panel matches the output power of the chopper or the inverter. A power conversion device for photovoltaic power generation, which is characterized by this. It is a control method for a photovoltaic power converter that converts DC power output from a solar panel into AC power and outputs it to the grid.
At regular times, the maximum power point tracking control that controls the panel voltage of the solar panel by the chopper is performed based on the voltage detection value of the output voltage of the solar panel and the current detection value of the output current, and the input side of the inverter Based on the DC voltage detection value, the inverter controls the DC voltage of the DC circuit connecting the chopper and the inverter, and performs DC voltage control.
When an output suppression command is input to the power converter for solar power generation, the chopper performs DC voltage control that controls the DC voltage of the DC circuit connecting the chopper and the inverter, and the inverter outputs the output of the inverter. Switch the control method to implement active power control to control the power ,
When the panel voltage of the solar panel drops, an output power correction command is output to the chopper and the inverter to suppress the output power of the power conversion device for photovoltaic power generation. How to control the converter. It is a control method for a photovoltaic power converter that converts DC power output from a solar panel into AC power and outputs it to the grid.
At regular times, the maximum power point tracking control that controls the panel voltage of the solar panel by the chopper is performed based on the voltage detection value of the output voltage of the solar panel and the current detection value of the output current, and the input side of the inverter Based on the DC voltage detection value, the inverter controls the DC voltage of the DC circuit connecting the chopper and the inverter, and performs DC voltage control.
When an output suppression command is input to the power converter for solar power generation, the chopper performs DC voltage control that controls the DC voltage of the DC circuit connecting the chopper and the inverter, and the inverter outputs the output of the inverter. Switch the control method to implement active power control to control the power,
When the amount of solar radiation to the solar panel decreases, an output power correction command is output to the chopper and the inverter to suppress the output power of the power conversion device for photovoltaic power generation. How to control the power converter. It is a control method for a photovoltaic power converter that converts DC power output from a solar panel into AC power and outputs it to the grid.
At regular times, the maximum power point tracking control that controls the panel voltage of the solar panel by the chopper is performed based on the voltage detection value of the output voltage of the solar panel and the current detection value of the output current, and the input side of the inverter Based on the DC voltage detection value, the inverter controls the DC voltage of the DC circuit connecting the chopper and the inverter, and performs DC voltage control.
When an output suppression command is input to the power converter for solar power generation, the chopper performs DC voltage control that controls the DC voltage of the DC circuit connecting the chopper and the inverter, and the inverter outputs the output of the inverter. Switch the control method to implement active power control to control the power,
When an output suppression command is input to the photovoltaic power conversion device, the difference power between the output power of the solar panel and the output power of the chopper or the inverter is converted into a DC that connects the solar panel and the chopper. A control method for a photovoltaic power conversion device, characterized in that the panel voltage of the solar panel is increased by charging and discharging in a circuit. The method for controlling a photovoltaic power conversion device according to any one of claims 7 to 9 .
Evaluation data indicating the operating state of the power conversion device for photovoltaic power generation is calculated, and
A control method for a power converter for photovoltaic power generation, which comprises transmitting the calculated evaluation data to the outside. The method for controlling a power conversion device for photovoltaic power generation according to any one of claims 7 to 10 .
When an output suppression command is input to the photovoltaic power conversion device, the panel voltage of the solar panel is increased until the output power of the solar panel matches the output power of the chopper or the inverter. A control method for a photovoltaic power converter, which is characterized by.

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