KR101671078B1 - Maximum power point tracking apparatus and method - Google Patents

Abstract

A device and method for monitoring the maximum power point of a photovoltaic power generation system capable of quickly finding the actual maximum power point and operating accordingly even if multiple peak power points appear on the PV panel output due to shading of the PV panel of the PV system . The maximum power point tracking device of the solar power generation system includes a PV panel and a power conditioning circuit connected between the PV panel and the load to adjust the power flow according to the control signal so that the PV panel is operated at a maximum power point A first switch for shorting / opening both output terminals of the PV panel; A capacitor connected between the two output terminals of the PV panel; A second switch for shorting / opening one output of the PV panel and one input of the power conditioning circuit; And for detecting the output voltage and the output current from the short-circuit operation point to the open operation point of the PV panel by controlling the short-circuit / open state of the first switch and the second switch for maximum power point tracking control, And a maximum power operation control unit for generating the control signal for operating the maximum power operation point and providing the control signal to the power conditioning circuit.

Description

TECHNICAL FIELD The present invention relates to a maximum power point tracking apparatus and method for a photovoltaic power generation system,

The present invention relates to an apparatus and method for monitoring a maximum power point of a photovoltaic power generation system, and more particularly, to a system and method for monitoring a maximum power point of a photovoltaic power generation system, To a maximum power point tracking apparatus and method of a photovoltaic power generation system capable of finding and operating a maximum power point.

Generally, PV system consists of PV (PhotoVoltaic) panel and Power Conditioning System (PCS). The PV panel functions as a solar cell array, a PV panel, a solar module, and the like (hereinafter referred to as a "PV panel"). In addition, the power conditioning system functions to properly adjust and convert the DC power output from the PV panel.

One of the important roles of the power conditioning system is the maximum power point operation function which adjusts the power output from the PV panel to the maximum power.

The efficiency of the PV panel is low, about 20%, and the difference of the output power varies depending on the current / voltage operation condition due to the characteristics of the PV panel. Accordingly, the photovoltaic power generation system needs to be operated to maximize its efficiency.

Since the maximum power point (MPP) of the output of the PV panel varies depending on the ambient temperature and the irradiation dose, the power conditioning system is able to adjust the maximum power point Point Tracking: MPPT) algorithm.

1 is a graph showing IV output characteristics and PV output characteristics of a typical PV panel. 1, when the output terminal of the PV panel is short-circuited, the short-circuit current I _sc flows through the output of the PV panel. When the output terminal of the PV panel is opened, the output voltage is the open- _oc ). The operating point (MPP) at which the output power of the PV panel reaches its maximum is between the two operating conditions of open operation and short-circuit operation. At this time, the output voltage and output current of the PV panel at the maximum power operation point are V _mpp and I _mpp , and the maximum power P _mpp is output.

Fig. 2 is a graph showing the IV output characteristics of a typical PV panel according to work love; Fig. As shown in FIG. 2, when the solar radiation amount increases, the short circuit current I _sc of the PV panel increases in proportion thereto. In FIG. 2, the maximum power operation point (MPP) is indicated by a dot on the IV characteristic curve according to the irradiation amount. In FIG. 2, it can be seen that the maximum power operating point (MPP) varies in the IV characteristic curve as the solar irradiance changes. Therefore, in order to maximize the generated power of the PV panel, it is necessary to find a new maximum power operating point (MPP) according to the changed amount of the solar radiation.

Generally, the Perturb and Observe (P & O) algorithm is applied for maximum power follow-up operation. The P & O algorithm determines the direction of the voltage disturbance (Vref) in the next MPPT period by observing the change in the output power generated after applying the voltage disturbance (Vref) of a certain magnitude to the output terminal voltage of the solar panel, So that the output power of the output terminal is maximized.

More specifically, the P & O algorithm uses the shape of the power-voltage characteristic curve indicated by a red curve in FIG. 1, and when the voltage disturbance (Vref) is applied, Finding a point.

For example, when the output voltage calculated in the current detection period is compared with the output power calculated in the previous voltage / current detection period (the detection period can be arbitrarily set), when the output voltage increases and the power also increases, It is judged that the operation has been performed from the left side of the maximum point in the power characteristic curve, and it is possible to further increase the voltage disturbance (Vref) so as to approach the maximum power operation point on the right side in the next cycle.

As another example, when the output voltage decreases and the power increases when the previous detection period is compared with the current detection period, it is determined that the operation is performed on the right side of the maximum point in the voltage-power characteristic curve, So that the voltage disturbance Vref is further reduced.

As another example, when the output voltage increases and the power decreases when the previous detection period is compared with the current detection period, it is determined that the operation is performed on the right side of the maximum point in the voltage-power characteristic curve. It is possible to further reduce the voltage disturbance (Vref) so as to be close to the point.

In the last example, when the output voltage decreases and the power decreases when the previous detection period is compared with the current detection period, it is determined that the operation is performed from the left of the maximum point in the voltage-power characteristic curve. So as to further increase the voltage disturbance (Vref).

The P & O algorithm repeats the maximum power follow-up operation as described above and finally finds a point where the power of the previous detection period and the power of the current detection period are the same.

However, since the environment in which the actual PV panel is applied is an open external environment in which sunlight can be easily received, the light receiving surface of the PV panel is obscured by dirt such as leaves, dirt, or algae, It may happen that the light is not received properly on the surface. In this specification, the disturbance in which the light is not properly received in a part of the PV panel will be unified into the term 'shade'.

3 is a graph showing an example in which multiple maximum power points are generated when shading occurs in a typical PV panel. As shown in FIG. 3, when shading occurs on a part of the light receiving surface of the PV panel, the IV characteristic curve and the PV characteristic curve of the PV panel are distorted to form multiple maximum power points. In this situation, when the P & O algorithm as described above is applied to control the maximum power operation point tracking from the open voltage (V _oc ), the actual maximum power operation point can not be found, There is a problem in that it can not find the exact maximum power point of the reality because it is trapped at the local maximum power point position on the right side.

Accordingly, the present invention provides a solar power generation system capable of quickly finding the actual maximum power point even when multiple peak power points appear on the output of the PV panel due to shading on the PV panel of the solar power generation system, And a tracking device and method.

According to an aspect of the present invention,

And a power conditioning circuit connected between the PV panel and the load for adjusting the power flow according to a control signal so that the PV panel is operated at a maximum power point, the maximum power point tracking device for a PV system ,

A first switch for shorting / opening both output terminals of the PV panel;

A capacitor connected between the two output terminals of the PV panel;

A second switch for shorting / opening one output of the PV panel and one input of the power conditioning circuit; And

The output voltage and the output current from the short-circuit operation point to the open operation point of the PV panel are detected by controlling the short-circuit / open state of the first switch and the second switch for the maximum power point follow- And generates the control signal for operating at the maximum power operating point and provides the control signal to the power conditioning circuit,

The maximum power point tracking device of the photovoltaic generation system.

In an embodiment of the present invention, the maximum power operation control section may provide the control signal for operating the maximum power operation point to the power conditioning circuit every predetermined operation cycle.

In one embodiment of the present invention, when the maximum power point follow-up control is started, the maximum power operation control section short-circuits the first switch and opens the second switch so that both output terminals of the PV panel are short- The first switch is opened to detect the output voltage and the output current of the PV panel while the output power of the PV panel charges the capacitor, and the maximum power operation And provide the control signal to the power conditioning circuit for operation with the maximum power operating point.

In one embodiment of the present invention, the first switch is a MOSFET having a drain and a source respectively connected to both output ends of the PV panel, and the second switch has an anode connected to one output terminal of the PV panel, A thyristor connected to one input terminal of the conditioning circuit, and the maximum power operation section can provide a gate signal of the MOSFET and the thyristor.

In one embodiment of the present invention, the power conditioning circuit includes a buck converter, and the control signal provided at the maximum power operation control section is a control signal for determining the duty of the internal switching device of the buck converter for maximum power point operation And may be a PWM driving signal of the switching element.

에 따라 결정할 수 있다. 상기 식에서, D는 듀티, RO는 상기 부하의 값, V_mpp는 상기 최대 전력 운전 제어부에 의해 결정된 최대 전력 운전점에서 상기 PV 패널의 출력 전압, I_mpp는 상기 최대 전력 운전 제어부에 의해 결정된 최대 전력 운전점에서 상기 PV 패널의 출력 전류이다.
In one embodiment of the present invention, the maximum power operation control unit sets the duty to Expression

. ≪ / RTI > V _mpp is the output voltage of the PV panel at the maximum power operation point determined by the maximum power operation control unit, I _mpp is the maximum output power determined by the maximum power operation control unit, D is the duty, RO is the load value, Is the output current of the PV panel at the operating point.

According to another aspect of the present invention,

And a power conditioning circuit coupled between the PV panel and the load for adjusting the power flow according to a control signal such that the PV panel is operated at a maximum power point, characterized in that the maximum power point tracking method of the PV system ,

Shorting a first switch connected between the two output terminals of the PV panel when the maximum power point following operation is started and opening a second switch connected between one output terminal of the PV panel and one input terminal of the power conditioning circuit;

Opening the first switch and charging a capacitor connected between the two output terminals of the PV panel;

Detecting an output voltage and an output current of the PV panel while the capacitor is charged;

Determining a maximum power operating point using the output voltage and the output current of the PV panel detected in the detecting step; And

Generating the control signal for operating with the maximum power operating point determined in the determining step and providing the control signal to the power conditioning circuit

The maximum power point tracking method of the photovoltaic generation system.

An embodiment of the present invention can repeat the opening step, the filling step, the detecting step, the determining step and the providing step at every predetermined operation cycle.

In one embodiment of the present invention, the first switch is a MOSFET having a drain and a source respectively connected to both output ends of the PV panel, and the second switch has an anode connected to one output terminal of the PV panel, The thyristor is connected to one input terminal of the conditioning circuit, and the MOSFET and the thyristor can be short-circuited / opened by receiving respective gate signals.

In one embodiment of the present invention, the power conditioning circuit includes a buck converter, which may be a PWM drive signal of the switching element that determines the duty of the internal switching element of the buck converter for maximum power point operation .

에 의해 결정될 수 있다. 상기 식에서, D는 듀티, RO는 상기 부하의 값, V_mpp는 상기 최대 전력 운전 제어부에 의해 결정된 최대 전력 운전점에서 상기 PV 패널의 출력 전압, I_mpp는 상기 최대 전력 운전 제어부에 의해 결정된 최대 전력 운전점에서 상기 PV 패널의 출력 전류이다.In one embodiment of the present invention,

Lt; / RTI > V _mpp is the output voltage of the PV panel at the maximum power operation point determined by the maximum power operation control unit, I _mpp is the maximum output power determined by the maximum power operation control unit, D is the duty, RO is the load value, Is the output current of the PV panel at the operating point.

According to the present invention, the output of all the sections from the short circuit operation point to the open circuit operation point of the PV cell is detected very quickly at the control operation cycle for the preset maximum power follow-up operation while maintaining the operation of the power conditioning circuit, It is possible to operate at the actual maximum power operation point even when the maximum power point of the multiple is generated due to shading on the surface of the PV panel because the operation point is searched.

1 is a graph showing IV output characteristics and PV output characteristics of a typical PV panel.
Fig. 2 is a graph showing the IV output characteristics of a typical PV panel according to work love; Fig.
3 is a graph showing an example in which multiple maximum power points are generated when shading occurs in a typical PV panel.
4 is a circuit diagram showing a maximum power point tracking apparatus of a solar power generation system according to an embodiment of the present invention.
5 is a flowchart illustrating a method of tracking a maximum power point of a solar power generation system according to an embodiment of the present invention.
6 is a graph showing the relationship between the IV characteristics of the PV cell and the duty of the buck converter in an external resistive load and conditioning circuit.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below. The embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. In addition, in describing the present invention, the defined terms are defined in consideration of the functions of the present invention, and they may be changed depending on the intention or custom of the technician working in the field, so that the technical components of the present invention are limited It will not be understood as meaning.

4 is a circuit diagram of a maximum power point tracking apparatus of a solar power generation system according to an embodiment of the present invention.

Referring to FIG. 4, the maximum power point tracking apparatus of the photovoltaic generation system according to the embodiment of the present invention is configured such that the PV panel 11 and the PV panel 11 constituting the solar power generation system are operated at the maximum power point And a power conditioning circuit (13) that adjusts the power flow so that it can be turned on. The maximum power point tracking apparatus of the photovoltaic generation system according to the embodiment of the present invention detects the output voltage and the output current of the PV panel 11 and applies the detected output voltage and output current to the predetermined algorithm, The controller 13 can generate and output a control signal for controlling the controller 13.

4, the maximum power point tracking apparatus of the photovoltaic generation system according to an embodiment of the present invention includes a first switch 21, a capacitor 23, a second switch 25, (27).

The first switch 21 is a switch whose short-circuit / open-circuit is controlled by the maximum power operation control unit 27. Both ends of the first switch 21 are connected to both output ends of the PV panel 11 so that both output ends of the PV panel 11 are electrically short-circuited when short-circuited. Both output terminals are electrically short-circuited.

The first switch 21 can be implemented as a MOSFET capable of rapid short / open state switching by a control signal. In this case, the drain and the source of the MOSFET are respectively connected to the two output terminals of the PV panel 11, and the control signal provided from the maximum power operation control section 27 is applied to the gate of the MOSFET to control the drain- So that it can operate as a switch.

Both ends of the capacitor 23 are connected to both output ends of the PV panel 11. That is, the capacitor 23 is connected in parallel with the first switch 21. When the first switch 21 is opened, the capacitor 23 is stored by the electric power outputted from the PV panel 11. When the first switch 21 is short-circuited, the charge charged in the capacitor 23 is stored in the first switch 21, (21). ≪ / RTI > The capacitor 23 can be used to detect the voltage between the two output terminals of the PV panel 11, that is, the output voltage of the PV panel 11. [

The second switch 25 electrically shorts / opens one output terminal of the PV panel 11 and one input terminal of the power conditioning circuit 13 to each other. The state of the second switch 25 can be controlled by the maximum power operation control section 27 like the first switch 21. [ The output power of the PV panel 11 is provided to the power conditioning circuit 13 when the second switch 25 is shorted and the power conditioning circuit 13 The power supply is interrupted.

The second switch 25 may be implemented as a thyristor in which the anode is connected to one output of the PV panel 11 and the cathode is connected to one input of the power conditioning circuit 13. [ The control signal of the maximum power operation control section 27 is provided as a gate signal of the thyristor so that the open / short state of the thyristor can be controlled.

The maximum power operation control unit 27 outputs a control signal for controlling the power conditioning circuit 13 so that the PV panel 11 can operate at the maximum power.

The maximum power operation control unit 27 controls the states of the first switch 21 and the second switch 25 according to a predetermined routine to generate a control signal for controlling the power conditioning circuit 13, The output voltage and the output current of the PV panel 11 can be detected and the maximum power operating point can be found when the first switch 21 and the second switch 25 are in a specific state.

The maximum power operation control section 27 can control the power conditioning circuit 13 so as to be able to operate at the maximum power operating point. In addition, the maximum power operation control unit 27 may generate a control signal for controlling the power conditioning circuit 13 every predetermined operation cycle for a predetermined maximum power follow-up operation.

5 is a flowchart illustrating a method of tracking a maximum power point of a solar power generation system according to an embodiment of the present invention. The operation and operation of the maximum power point tracking device of the photovoltaic generation system according to an embodiment of the present invention will be described with reference to a method of tracking the maximum power point of the solar power generation system according to an embodiment of the present invention shown in FIG. A description of the effect can be made.

Referring to FIGS. 4 and 5, the maximum power point tracking method of the photovoltaic generation system according to the embodiment of the present invention is a method of tracking maximum power point (MPPT) (S11) of determining whether or not to start the operation. When the power conditioning circuit 13 is in operation in accordance with the control signal determined by the maximum power operation control unit 27 in the previous operation cycle, the maximum power operation control unit 27 starts the maximum power point following operation of the next cycle (S11). Immediately before the start of a new operation period, the first switch 21 is kept in the open state, the second switch 25 is kept in the short-circuited state, and the capacitor 23 is kept charged.

On the other hand, FIG. 4 shows, by way of example, a power conditioning circuit 13 implemented with a buck converter including a large capacity capacitor C _dc connected between two input terminals to which the output of the PV panel 11 is input. Thus, in the case of the power conditioning circuit 13 implemented with a buck converter, control for maximum power operation can be achieved by adjusting the duty of the PWM switching device S _buck of the buck converter. That is, in the case of the power conditioning circuit implemented with the buck converter as shown in FIG. 4, the control signal provided from the maximum power operation control unit 27 to the power conditioning circuit 13 is supplied to the PWM switching unit S _buck of the buck converter, It is possible to determine the duty of the signal and to enable the driving according to the duty.

In one embodiment of the present invention, a control signal generation technique for controlling the power conditioning circuit 13 implemented with a buck converter will be described later.

When it is determined in step S11 that the control for the maximum power point tracking in the next period is started, the maximum power operation control unit 27 short-circuits the first switch 21 and simultaneously turns on the second switch 25 ). In the case where the first switch 21 is implemented as a MOSFET and the second switch 25 is implemented as a thyristor in step S11, the maximum power operation control section 27 outputs the drive signal G _pulse , and blocks the drive signal G _SCR applied to the gate of the thyristor 25. When the driving signal G _pulse is applied to the gate of the MOSFET 21, the current flowing through the thyristor 25 is bypassed through the MOSFET 21, so that the thyristor 25 is completely opened State. Therefore, the electric charge charged in the DC link capacitor C _{dc at} both ends of the input stage of the power conditioning circuit 13 does not flow back through the MOSFET 21 to discharge. That is, the power conditioning circuit 13 can maintain normal operation using the energy charged in the DC link capacitor C _dc even when the MOSFET 21 is maintained in the short-circuited state. The capacity of the capacitor 23 is designed to be sufficiently smaller than the DC link capacitor C _dc so that the capacitor 23 can be discharged for a short time of a few milliseconds through the MOSFET 21 to short-circuit two output terminals of the PV panel 11 (The output voltage of the PV panel 11 becomes zero).

Next, the maximum power operation control unit 27 controls the first switch 21 in the short-circuit state to be in the open state (S15). That is, in step S15, the driving signal to the gate of the MOSFET 21 is cut off, so that the drain and the source of the MOSFET 21 are in an open state. By the power provided by the PV panel 11, Charging is started.

The maximum power operation control unit 27 controls the output of the PV panel 11 from the output voltage and output current of the PV panel 11 immediately before the charging of the capacitor 23 starts to the time when the charging of the capacitor 23 is completed, A change in the voltage V _pv and the output current I _pv is detected (S17). As described above, the output terminal of the PV panel 11 is short-circuited when the capacitor 23 is in the fully discharged state immediately before the capacitor 23 is charged. In this case, the short-circuit operation current Isc of the PV panel 11 of the short- .

When the first switch 21 is switched to the open state in the step S15, the capacitor 23 has a small capacity and is rapidly charged, so that the discharge time in the short period of several [ms] is substantially the same as the discharge time in the step S13 And is charged up to the open operation voltage (Voc) for a period of time. In other words, when the capacitor 23 is fully charged, both ends of the PV panel 11 are opened. The maximum power operation control unit 27 detects the change of the output voltage and the output current until both ends of the PV panel 11 are brought into the open state from the short circuit state and finally detects the open state voltage _Voc .

Next, the maximum power operation control unit 27 confirms the output voltage and the output current at which the maximum power is output by using the output voltage and the output current of the PV panel 11 detected in step S17, Is determined as the voltage and current (V _mpp and I _mpp ) of the maximum power operating point (S19). For example, the maximum power operation control section 27 detects the output voltage and the output current of the PV panel 11 simultaneously at predetermined intervals in step S17, and detects the output voltage and the output current So that the power can be confirmed. The output voltage and the output current indicating the maximum power value among the plurality of calculated power values can be determined as the voltage and currents (V _mpp and I _mpp ) at the maximum power operating point.

The maximum power operation control unit 27 then controls the power conditioning circuit 13 so that the PV panel 11 can output the voltage and currents V _mpp and I _mpp of the maximum power operating point determined in step S19 And provides the control signal to the power conditioning circuit 13. [ The power conditioning circuit 13 can operate the solar power generation system so that the output of the PV panel 11 maintains the maximum power by operating in accordance with the control signal.

As described above, in the maximum power point tracking apparatus and method of the photovoltaic power generation system according to the embodiment of the present invention, from the short circuit operation point of the PV cell 11 to the open circuit It is possible to operate at the actual maximum power operation point even when the maximum power point of the PV panel appears due to the generation of shading on the surface of the PV panel because the output of the entire section is detected to the operation point to find the maximum power operation point.

Hereinafter, a control method of the power conditioning circuit 13 including the buck converter shown in FIG. 4 will be described.

6 is a graph showing the relationship between the I-V characteristic of the PV cell and the duty of the buck converter in the external resistance load and conditioning circuit.

The power conditioning circuit 13 employing the buck converter can enable maximum power operation by controlling the duty of the PWM switching device (S _buck ) in the buck converter. The duty decision algorithm for maximum power operation control using the buck converter can introduce the concept of the equivalent load resistance R _eq viewed from the input stage side of the power conditioning circuit 13 connected to the output terminal of the PV panel 11 . It can be understood that the equivalent load resistance R _{eq is} formed by the load resistance of the power conditioning circuit itself and the external resistance load R ₀ connected to the output stage of the power conditioning circuit 13. [

A process of obtaining the equivalent load resistance R _eq formed by the buck converter and the external resistance load R ₀ will be described.

First, the average power P _in input to the buck converter in the power conditioning circuit 13 can be calculated by the input voltage V _in and the input current I _in as follows:

[Formula 1]

In addition, the average power Pout output from the buck converter is calculated by the output voltage Vo and the output current I _o as follows:

[Formula 2]

In the ideal case, because P _in = P _out by the energy conservation law, the following Equation 3 can be established.

[Formula 3]

Consequently, the equivalent load resistance (Req) can be calculated as shown in Equation 4 below.

[Formula 4]

The relationship between the output voltage V _pv and the output current I _pv of the PV panel 11 is given by the following Equation 5 since the resistance connected to the entire output terminal of the PV panel 11 is the equivalent load resistance R _eq And Equation 5 can be expressed by a straight line having a slope 'D ² / R _o ' in the IV graph shown in FIG. 6 and passing through the origin.

[Formula 5]

As shown in Fig. 6, the point at which the straight line formed by the equation (5) meets the IV characteristic curve of the PV panel can be the operating point of the PV panel. Thus, by controlling the duty (D) of the PWM switching element (S _buck ) of the buck converter in the power conditioning circuit 13, the operating point of the PV panel can be determined.

As described above, according to the embodiment of the present invention, the voltage and current (V _mpp) capable of operating at the maximum power in the entire operation period through the output voltage and the output current varying from the short- and so find I _mpp), it is substituted for the maximum power driving voltage and current (V _mpp and I _mpp) in expression 5 can determine the maximum power driving the duty (D available) as shown in the following formula 6.

[Formula 6]

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Therefore, the scope of the present invention should not be limited to the embodiments described, but should be determined by the scope of the following claims and equivalents thereof.

11: PV panel 13: Power conditioning circuit
21: first switch (MOSFET) 23: capacitor
25: second switch (thyristor) 27: maximum power operation control section

Claims (11)

And a power conditioning circuit coupled between the PV panel and the load for adjusting the power flow according to a control signal such that the PV panel is operated at a maximum power point, the maximum power point tracking device of the PV system comprising:
A first switch connected in parallel at both output ends of the PV panel to short-circuit / open;
A capacitor connected in parallel to both output terminals of the PV panel;
A second switch connected to one output of the PV panel and connected to one input of the power conditioning circuit for shorting / opening; And
The short-circuit / open state of the first switch and the second switch is repeatedly controlled for each of the control operation cycles for the maximum power follow-up control for the maximum power point follow-up control so that the short- And outputs the control signal as a PWM driving signal of the power conditioning circuit to operate at the maximum power operating point, and supplies the control signal to the power conditioning circuit A maximum power operation control unit,
Wherein the maximum power operation control unit comprises:
When the maximum power point tracking control is started, the first switch is short-circuited and the second switch is opened to make both output terminals of the PV panel short-circuited, and then the first switch is opened to output the output Detecting an output voltage and an output current of the PV panel while power is charging the capacitor, determining the maximum power operating point using the detected output voltage and the output current, and operating the maximum power operating point Generate and supply a control signal to the power conditioning circuit,
The power conditioning circuit includes a buck converter,
Wherein the buck converter comprises a DC link capacitor connected between both inputs of the power conditioning circuit and having a capacitance greater than the capacitor,
Wherein the control signal provided by the maximum power operation control unit includes:
And the PWM driving signal of the switching element which determines the duty of the switching element of the buck converter for maximum power point operation. delete delete The method according to claim 1,
Wherein the first switch is a MOSFET whose drain and source are respectively connected to both output terminals of the PV panel and the second switch is a thyristor having an anode connected to one output of the PV panel and a cathode connected to one input of the power conditioning circuit, And the maximum power operation unit provides a gate signal of the MOSFET and the thyristor. delete The method according to claim 1,
Wherein the maximum power operation control unit comprises:
The above-

_Wherein D is a duty, RO is a value of the load, and V _mpp is a maximum power operation point determined by the maximum power operation control unit. The output voltage of the PV panel, I _mpp is the output current of the PV panel at the maximum power operating point determined by the maximum power operation control unit). A method of tracking a maximum power point of a solar power generation system using a maximum power point tracking apparatus of the solar power generation system according to claim 1,
Wherein when a maximum power point tracking operation is repeatedly performed every control operation cycle for a preset maximum power follow-up operation, a first switch connected in parallel to both output ends of the PV panel is short-circuited and connected to one output terminal of the PV panel, Opening a second switch connected to one input of the conditioning circuit;
Opening the first switch and charging capacitors connected in parallel at both output ends of the PV panel;
Detecting an output voltage and an output current of the entire section from a short-circuit operation point to an open operation point of the PV panel while the capacitor is charged;
Determining a maximum power operating point using the output voltage and the output current of the PV panel detected in the detecting step; And
Generating the control signal, which is a PWM driving signal of the power conditioning circuit for operating with the maximum power operating point determined in the determining step, to provide the control signal to the power conditioning circuit
Wherein the maximum power point tracking method of the photovoltaic generation system comprises: delete 8. The method of claim 7,
Wherein the first switch is a MOSFET whose drain and source are respectively connected to both output terminals of the PV panel and the second switch is a thyristor having an anode connected to one output of the PV panel and a cathode connected to one input of the power conditioning circuit, And the MOSFET and the thyristor are supplied with respective gate signals to determine a short circuit / open circuit. delete 8. The method of claim 7,
The duty < RTI ID =

_Wherein D is the duty, RO is the value of the load, and V _mpp is the maximum power operation point determined by the maximum power operation control unit. The output voltage of the PV panel, I _mpp is the output current of the PV panel at the maximum power operating point determined by the maximum power operation control unit).

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