阅读说明：本技术 一种应用于三相光伏逆变电路的控制方法及相关装置 (Control method applied to three-phase photovoltaic inverter circuit and related device ) 是由 胡雪凯 孟良 曾四鸣 王振雄 范辉 易皓 张乾 于 2020-12-23 设计创作，主要内容包括：本申请提供一种应用于三相光伏逆变电路的控制方法及相关装置,涉及电力控制技术领域,该控制方法包括：基于三相逆变电路的直流侧的电压、电流、预设电压参考值,和光伏发电电源的光伏输出功率、光伏输出电压,以及一个以上PI控制器,控制升压变换电路中开关管的通断；基于三相逆变电路的交流侧的预设交流角频率参考值、各相电压、各相电流、各滤波电容电流、派克变换法、派克反变换法,和一个以上PI控制器,控制三相逆变电路中开关管的通断。基于本申请的技术方案,可有效降低光伏系统的运营成本。(The application provides a control method and a related device applied to a three-phase photovoltaic inverter circuit, and relates to the technical field of power control, wherein the control method comprises the following steps: on the basis of the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply and more than one PI controller, the on-off of a switch tube in the boost conversion circuit is controlled; the on-off of a switching tube in the three-phase inverter circuit is controlled based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller. Based on the technical scheme of this application, can effectively reduce photovoltaic system's operation cost.)

1. A control method applied to a three-phase photovoltaic inverter circuit, wherein the three-phase photovoltaic inverter circuit comprises a boost conversion circuit and a three-phase inverter circuit, and an input end of the boost conversion circuit is used for being electrically connected with a photovoltaic power generation power supply, and the control method comprises the following steps:

controlling the on-off of a switching tube in the boost conversion circuit based on the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply and more than one PI controller;

and controlling the on-off of a switching tube in the three-phase inverter circuit based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

2. The control method according to claim 1, wherein the controlling on/off of a switching tube in the boost converter circuit based on the voltage, the current, a preset voltage reference value on the dc side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and one or more PI controllers comprises:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

performing integral proportion operation on the third value based on a second preset PI controller to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

3. The control method according to claim 1 or 2, wherein the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which correspond to the push-pull branches one to one, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current of each filter capacitor;

the control of the on-off of the switching tube in the three-phase inverter circuit based on the preset alternating current angular frequency reference value, the phase voltage, the phase current, the filter capacitor current, the park transformation method, the park inverse transformation method and the more than one PI controller on the alternating current side of the three-phase inverter circuit comprises the following steps:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

4. The control method according to claim 3, wherein the controlling the on/off of the switching tubes in the three parallel push-pull branches based on the preset AC angular frequency reference value on the AC side of the three-phase inverter circuit, the phase voltages, the phase currents, the filter capacitor currents, the park transformation method, the park inverse transformation method, and one or more PI controllers comprises:

acquiring each phase voltage, each phase current and each filter capacitor current of the alternating current side based on the three-phase inverter circuit;

carrying out park transformation on each phase voltage, each phase current and each filter capacitor current at the alternating current side of the three-phase inverter circuit based on a preset alternating current angular frequency reference value and a park transformation method at the alternating current side of the three-phase inverter circuit so as to obtain a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component and a filter capacitor current q-axis component;

calculating reactive power based on the voltage d-axis component, the voltage q-axis component, the current d-axis component, the current q-axis component, and equation (1);

the formula (1) is specifically as follows:

wherein Q is the reactive power, U_qFor the d-axis component of the voltage, U_dIs a stand forThe q-axis component of the voltage, I_gdIs the d-axis component of the current, I_gqIs the current q-axis component;

subtracting a preset reactive power reference value from the reactive power to obtain a ninth value;

subtracting the ninth value of the preset multiple from the preset grid-connected point voltage reference value to obtain a tenth value;

subtracting the d-axis component of the voltage from the tenth value to obtain an eleventh value;

performing integral proportional operation on the eleventh value based on a fifth preset PI controller to obtain a twelfth value;

subtracting the filter capacitor current d-axis component from the twelfth value to obtain a thirteenth value;

performing integral proportional operation on the thirteenth value based on a sixth preset PI controller to obtain a fourteenth value;

subtracting the voltage q-axis component from 0 to obtain a fifteenth value;

performing integral proportion operation on the fifteenth value based on a seventh preset PI controller to obtain a sixteenth value;

subtracting the filter capacitor current q-axis component from the sixteenth value to obtain a seventeenth value;

performing integral proportional operation on the seventeenth value based on an eighth preset PI controller to obtain an eighteenth value;

performing inverse park transformation on the fourteenth value and the eighteenth value based on an inverse park transformation method to obtain a first voltage value, a second voltage value and a third voltage value;

and generating a second control signal based on the first voltage value, the second voltage value and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal.

5. The control method of claim 4, wherein the three pairs of push-pull switching tubes comprise: the switch comprises a first pair of push-pull switch tubes, a second pair of push-pull switch tubes and a third pair of push-pull switch tubes, wherein the first pair of push-pull switch tubes comprises: a first push-pull switch tube and a second push-pull switch tube, the second pair of push-pull switch tubes comprising: a third push-pull switch tube and a fourth push-pull switch tube, the third pair of push-pull switch tubes comprising: the negative electrode of the first push-pull switching tube, the negative electrode of the third push-pull switching tube and the negative electrode of the fifth switching tube are used for respectively outputting each phase alternating current of the three-phase alternating current;

the second control signal includes: a first PWM control signal, a second PWM control signal, and a third PWM control signal;

the generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal includes:

calculating a nineteenth value, a twentieth value, and a twenty-first value based on the first voltage value, the second voltage value, the third voltage value, equation (2), equation (3), and equation (4);

the formula (2), the formula (3) and the formula (4) are respectively specifically:

wherein D is₁Is the nineteenth value, D₂Is the twentieth value, D₃Is the twenty-first value, U_dcIs the voltage of the direct current side of the three-phase inverter circuit,is a stand forThe first voltage value is set to be a first voltage value,is the value of the second voltage, and is,is the third voltage value;

performing PWM modulation on the nineteenth, twentieth, and twenty-first values with a preset carrier, respectively, to generate the first, second, and third PWM control signals;

controlling the first push-pull switch tube based on the first PWM control signal, and controlling the second push-pull switch tube based on a control signal complementary to the first PWM control signal;

controlling the third push-pull switch tube based on the second PWM control signal, and controlling the fourth push-pull switch tube based on a control signal complementary to the second PWM control signal;

and controlling the fifth push-pull switching tube based on the third PWM control signal, and controlling the sixth push-pull switching tube based on a control signal complementary to the third PWM control signal.

6. The utility model provides a be applied to three-phase photovoltaic inverter circuit's controlling means, three-phase photovoltaic inverter circuit includes boost converter circuit and three-phase inverter circuit, boost converter circuit's input is used for with photovoltaic power generation power electric connection, its characterized in that, controlling means includes:

the first control unit is used for controlling the on-off of a switching tube in the boost conversion circuit based on the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply and more than one PI controller;

and the second control unit is used for controlling the on-off of a switching tube in the three-phase inverter circuit based on a preset alternating current angular frequency reference value on the alternating current side of the three-phase inverter circuit, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method and more than one PI controller.

7. The control device according to claim 6, wherein the first control unit is specifically configured to:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

performing integral proportion operation on the third value based on a second preset PI controller to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

8. The control device according to claim 6 or 7, wherein the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which correspond to the push-pull branches one to one, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current of each filter capacitor;

the second control unit is specifically configured to:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

9. A control device applied to a three-phase photovoltaic inverter circuit, the three-phase photovoltaic inverter circuit comprising a boost converter circuit and a three-phase inverter circuit, an input end of the boost converter circuit being used for electrically connecting with a photovoltaic power generation power supply, wherein the control device comprises a memory and a processor, the memory stores a computer program, and the processor implements the steps of the method according to any one of claims 1 to 5 when executing the computer program.

10. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 5.

Technical Field

The present disclosure relates to the field of power control technologies, and in particular, to a control method and a related apparatus for a three-phase photovoltaic inverter circuit.

Background

In recent years, energy shortage and environmental pollution have become serious problems facing countries all over the world, renewable energy sources such as photovoltaic power generation and the like have become hot spots due to the advantages of green environmental protection and renewable energy, and how to promote research and development of renewable energy power generation has become a main task in the field.

In the prior art, in the isolated island operation of a photovoltaic system, parameters such as power, voltage and frequency in the photovoltaic system are mainly adjusted through preset energy storage equipment to maintain stability, but the cost and the maintenance cost of the energy storage equipment are high, and the energy management system still needs to be matched to control the charging and discharging of the energy storage equipment, so that the operation cost of the photovoltaic system is greatly increased.

Disclosure of Invention

The application provides a control method and a related device applied to a three-phase photovoltaic inverter circuit, which can effectively reduce the operation cost of a photovoltaic system.

In order to achieve the above technical effect, a first aspect of the present application provides a control method applied to a three-phase photovoltaic inverter circuit, where the three-phase photovoltaic inverter circuit includes a boost converter circuit and a three-phase inverter circuit, an input end of the boost converter circuit is used for being electrically connected to a photovoltaic power generation power supply, and the control method includes:

controlling the on-off of a switching tube in the boost conversion circuit based on the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply and more than one PI controller;

and controlling the on-off of a switching tube in the three-phase inverter circuit based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

Based on the first aspect of the present application, in a first possible implementation manner, the controlling the on/off of the switching tube in the boost converter circuit based on the voltage, the current, the preset voltage reference value on the dc side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and one or more PI controllers includes:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

based on a second preset PI controller, performing integral proportion operation on the third value to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

Based on the first aspect of the present application or the first possible implementation manner of the first aspect of the present application, in a second possible implementation manner, the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which are in one-to-one correspondence with the push-pull branches, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current of each filter capacitor;

the above preset ac angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, park transformation method, park inverse transformation method based on the ac side of the above three-phase inverter circuit, and one or more PI controllers, the controlling the on/off of the switching tube in the above three-phase inverter circuit includes:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

Based on the second possible implementation manner of the first aspect of the present application, in a third possible implementation manner, the controlling on/off of the switching tubes in the three parallel push-pull branches based on the preset ac angular frequency reference value at the ac side of the three-phase inverter circuit, the phase voltages, the phase currents, the filter capacitor currents, the park transformation method, the park inverse transformation method, and one or more PI controllers includes:

acquiring each phase voltage, each phase current and each filter capacitor current on the alternating current side based on the three-phase inverter circuit;

carrying out park transformation on each phase voltage, each phase current and each filter capacitor current at the alternating current side of the three-phase inverter circuit based on a preset alternating current angular frequency reference value and a park transformation method at the alternating current side of the three-phase inverter circuit so as to obtain a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component and a filter capacitor current q-axis component;

calculating reactive power based on the voltage d-axis component, the voltage q-axis component, the current d-axis component, the current q-axis component, and equation (1);

the formula (1) is specifically:

wherein Q is the above reactive power, U_qFor the d-axis component of the voltage, U_dFor the q-axis component of the voltage, I_gdFor the d-axis component of the current, I_gqIs the above-mentioned current q-axis component;

subtracting a preset reactive power reference value from the reactive power to obtain a ninth value;

subtracting the ninth value of the preset multiple from the preset grid-connected point voltage reference value to obtain a tenth value;

subtracting the d-axis component of the voltage from the tenth value to obtain an eleventh value;

performing integral proportional operation on the eleventh value based on a fifth preset PI controller to obtain a twelfth value;

subtracting the d-axis component of the filter capacitor current from the twelfth value to obtain a thirteenth value;

performing integral proportional operation on the thirteenth value based on a sixth preset PI controller to obtain a fourteenth value;

subtracting the q-axis component of the voltage from 0 to obtain a fifteenth value;

performing integral proportion operation on the fifteenth value based on a seventh preset PI controller to obtain a sixteenth value;

subtracting the q-axis component of the filter capacitor current from the sixteenth value to obtain a seventeenth value;

performing integral proportional operation on the seventeenth value based on an eighth preset PI controller to obtain an eighteenth value;

performing inverse park transform on the fourteenth value and the eighteenth value based on an inverse park transform method to obtain a first voltage value, a second voltage value and a third voltage value;

generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal

Based on the third possible implementation manner of the first aspect of the present application, in a fourth possible implementation manner, the three pairs of push-pull switching tubes include: the first pair of push-pull switch tubes, the second pair of push-pull switch tubes and the third pair of push-pull switch tubes, the first pair of push-pull switch tubes comprises: a first push-pull switch tube and a second push-pull switch tube, wherein the second pair of push-pull switch tubes comprises: a third push-pull switch tube and a fourth push-pull switch tube, wherein the third pair of push-pull switch tubes comprises: a fifth push-pull switching tube and a sixth push-pull switching tube, wherein the negative electrode of the first push-pull switching tube, the negative electrode of the third push-pull switching tube and the negative electrode of the fifth switching tube are used for respectively outputting each phase alternating current of three-phase alternating current;

the second control signal includes: a first PWM control signal, a second PWM control signal, and a third PWM control signal;

the generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal includes:

calculating a nineteenth value, a twentieth value, and a twenty-first value based on the first voltage value, the second voltage value, the third voltage value, equation (2), equation (3), and equation (4);

the formula (2), the formula (3), and the formula (4) are each specifically:

wherein D is₁Is the above nineteenth value, D₂Is the twentieth value, D₃Is the second eleventh value, U_dcThe voltage on the dc side of the three-phase inverter circuit,in order to achieve the first voltage value mentioned above,the second voltage value is a value of the second voltage,the third voltage value;

PWM modulating the nineteenth, twentieth, and twenty-first values with a preset carrier, respectively, to generate the first, second, and third PWM control signals;

controlling the first push-pull switch tube based on the first PWM control signal, and controlling the second push-pull switch tube based on a control signal complementary to the first PWM control signal;

controlling the third push-pull switch tube based on the second PWM control signal, and controlling the fourth push-pull switch tube based on a control signal complementary to the second PWM control signal;

and controlling the fifth push-pull switching tube based on the third PWM control signal, and controlling the sixth push-pull switching tube based on a control signal complementary to the third PWM control signal.

This application second aspect provides a be applied to three-phase photovoltaic inverter circuit's controlling means, above-mentioned three-phase photovoltaic inverter circuit includes boost converter circuit and three-phase inverter circuit, above-mentioned boost converter circuit's input be used for with photovoltaic power generation power electric connection, above-mentioned controlling means includes:

the first control unit is used for controlling the on-off of a switch tube in the boost conversion circuit based on the voltage, the current and a preset voltage reference value on the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and more than one PI controller;

and the second control unit is used for controlling the on-off of a switching tube in the three-phase inverter circuit based on a preset alternating current angular frequency reference value on the alternating current side of the three-phase inverter circuit, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method and more than one PI controller.

Based on the second aspect of the present application, in a first possible implementation manner, the first control unit is specifically configured to:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

based on a second preset PI controller, performing integral proportion operation on the third value to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

In a second possible implementation manner, based on the second aspect of the present application or the first possible implementation manner of the second aspect of the present application, the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which are in one-to-one correspondence with the push-pull branches, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current of each filter capacitor;

the second control unit is specifically configured to:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

A third aspect of the present application provides a control device applied to a three-phase photovoltaic inverter circuit, where the three-phase photovoltaic inverter circuit includes a boost converter circuit and a three-phase inverter circuit, an input end of the boost converter circuit is used for being electrically connected to a photovoltaic power generation power supply, the control device includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the control method mentioned in the first aspect or any one of the possible implementation manners of the first aspect when executing the computer program.

A fourth aspect of the present application provides a computer-readable storage medium having a computer program, which when executed by a processor implements the steps of the control method mentioned in the first aspect or any of the possible implementations of the first aspect.

From the above, the technical scheme of the application includes that on the basis of the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and more than one PI controller are used for controlling the on-off of a switch tube in the boost conversion circuit; the on-off of a switching tube in the three-phase inverter circuit is controlled based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method of the alternating current side of the three-phase inverter circuit and more than one PI controller. According to the technical scheme, all items of data acquired in the three-phase photovoltaic inverter circuit can be processed to obtain a plurality of control signals, and then all switch tubes in the three-phase photovoltaic inverter circuit are controlled based on the plurality of control signals, so that the technical effect that a photovoltaic system comprising the three-phase photovoltaic inverter circuit can be maintained to be stable without using energy storage equipment is achieved, and the operation cost of the photovoltaic system is reduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed for the embodiments or the prior art descriptions will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and for a person of ordinary skill in the art, other drawings can be obtained according to the drawings without inventive labor.

Fig. 1 is a schematic flowchart of an embodiment of a control method applied to a three-phase photovoltaic inverter circuit provided in the present application;

fig. 2 is a schematic structural diagram of an embodiment of a three-phase photovoltaic inverter circuit provided in the present application;

fig. 3 is a schematic flowchart of an embodiment of a PI control method applied to a boost converter circuit according to the present disclosure;

fig. 4 is a schematic flowchart of an embodiment of a PI control method applied to a three-phase inverter circuit according to the present disclosure;

fig. 5 is a schematic structural diagram of an embodiment of a control device applied to a three-phase photovoltaic inverter circuit provided in the present application;

fig. 6 is a schematic structural diagram of another embodiment of the control device applied to the three-phase photovoltaic inverter circuit provided in the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth, such as particular system structures, techniques, etc. in order to provide a thorough understanding of the embodiments of the present application. However, it will be apparent to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It will be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It is also to be understood that the terminology used in the description of the present application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used in the specification of the present application and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

The technical solutions in the embodiments of the present application are clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application, but the present application may be practiced in other ways than those described herein, and it will be apparent to those of ordinary skill in the art that the present application is not limited by the specific embodiments disclosed below.

Example one

The application provides a control method for three-phase photovoltaic inverter circuit, and above-mentioned three-phase photovoltaic inverter circuit includes boost converter circuit and three-phase inverter circuit, and above-mentioned boost converter circuit's input is used for with photovoltaic power generation power electric connection, as shown in fig. 1, above-mentioned control method includes:

step 101, starting the three-phase photovoltaic inverter circuit;

in this embodiment, as shown in fig. 2, the three-phase photovoltaic inverter circuit includes a boost converter circuit and a three-phase inverter circuit, and the boost converter circuit may include: the three-phase inverter circuit comprises an inductor 201, a diode 202, a first switch 203 and a first capacitor 204, and may include: a second switching tube 205, a third switching tube 206, a fourth switching tube 207, a fifth switching tube 208, a sixth switching tube 209, a seventh switching tube 210, a second capacitor 211, a third capacitor 212 and a fourth capacitor 213;

one end of an inductor 201 is used for being electrically connected with the anode of a photovoltaic power generation power supply, the other end of the inductor 201 is respectively electrically connected with the anode of a diode 202 and the anode of a first switch tube 203, the other end of the first switch tube 203 is used for being electrically connected with the cathode of the photovoltaic power generation power supply, the cathode of the diode 202 is respectively electrically connected with one end of a first capacitor 204, the anode of a second switch tube 205, the anode of a fourth switch tube 207 and the anode of a sixth switch tube 209, the cathode of the second switch tube 205 is respectively electrically connected with the anode of the third switch tube 206 and one end of a second capacitor 211, the cathode of the fourth switch tube 207 is respectively electrically connected with the anode of a fifth switch tube 208 and one end of a third capacitor 212, the cathode of the sixth switch tube 209 is respectively electrically connected with one end of a seventh switch tube 210 and one end of a fourth capacitor 213, the other end of the first switch tube 203 is respectively electrically connected with the other end of the first capacitor 204 and the other end of the second capacitor 204, The cathode of the second switch tube 206, the cathode of the fourth switch tube 208, the cathode of the sixth switch tube 210, the other end of the second capacitor 211, the other end of the third capacitor 212, and the other end of the fourth capacitor 213 are electrically connected, and the cathode of the second switch tube 205, the cathode of the fourth switch tube 207, and the cathode of the sixth switch tube 209 are the ac power output terminals of the three-phase ac power output terminal of the three-phase inverter circuit.

Specifically, above-mentioned three-phase photovoltaic inverter circuit still includes: a switching tube control device, configured to send corresponding control signals to the first switching tube 203, the second switching tube 205, the third switching tube 206, the fourth switching tube 207, the fifth switching tube 208, the sixth switching tube 209 and the seventh switching tube 210, respectively, so as to control on/off of switches of the first switching tube 203, the second switching tube 205, the third switching tube 206, the fourth switching tube 207, the fifth switching tube 208, the sixth switching tube 209 and the seventh switching tube 210, respectively;

the above-mentioned three-phase photovoltaic inverter circuit that starts includes: and starting the switching tube control device.

After step 101 is executed, the actions of step 102 and step 103 are triggered and executed at the same time.

102, controlling the on-off of a switching tube in the boost conversion circuit based on the voltage, the current and a preset voltage reference value on the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply and more than one PI controller;

in the embodiment of the present application, each parameter collected from the dc side of the three-phase inverter circuit (i.e., the input end of the three-phase inverter circuit) and the photovoltaic power generation power supply, and a preset voltage reference value may be subjected to data processing based on a plurality of preset PI controllers, so as to obtain a control signal for controlling the on/off of the switching tube in the boost conversion circuit.

And 103, controlling the on-off of a switching tube in the three-phase inverter circuit based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method, a park inverse transformation method and more than one PI controller on the alternating current side of the three-phase inverter circuit.

In the embodiment of the application, based on a plurality of preset PI controllers, data processing may be performed on parameters acquired from an ac side of the three-phase inverter circuit (that is, an output end of the three-phase inverter circuit) and each device on the three-phase inverter circuit, and a preset ac angular frequency reference value, so as to obtain a control signal for controlling on/off of a switching tube in the three-phase inverter circuit.

Alternatively, as shown in FIG. 3, U_dcIs the voltage on the DC side of the three-phase inverter circuit, U_dcrefFor a predetermined voltage reference value, P_pvFor the photovoltaic output power, U, of the above-mentioned photovoltaic power supply_pvFor the photovoltaic output voltage of the above-mentioned photovoltaic power generation power supply, I_inThe current of the direct current side of the three-phase inverter circuit;

the above-mentioned voltage, electric current, the default voltage reference value based on the direct current side of above-mentioned three-phase inverter circuit, and photovoltaic output power, the photovoltaic output voltage of above-mentioned photovoltaic power generation power to and more than one PI controller, the break-make that controls switch tube among the above-mentioned boost conversion circuit includes:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

based on a second preset PI controller, performing integral proportion operation on the third value to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

Optionally, the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which are in one-to-one correspondence with the push-pull branches, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current of each filter capacitor;

the above preset ac angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, park transformation method, park inverse transformation method based on the ac side of the above three-phase inverter circuit, and one or more PI controllers, the controlling the on/off of the switching tube in the above three-phase inverter circuit includes:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

Specifically, as shown in fig. 2, the three parallel push-pull branches may be a push-pull branch formed by connecting a second switching tube 205 and a third switching tube 206 in series, a push-pull branch formed by connecting a fourth switching tube 207 and a fifth switching tube 208 in series, and a push-pull branch formed by connecting a sixth switching tube 209 and a seventh switching tube 210 in series, and the filter capacitors corresponding to each push-pull branch one by one may be a second capacitor 211, a third capacitor 212, and a fourth capacitor 213.

Further, the controlling the on-off of the switching tubes in the three parallel push-pull branches based on the preset ac angular frequency reference value, the phase voltages, the phase currents, the filter capacitor currents, the park transformation method, the park inverse transformation method and the more than one PI controller on the ac side of the three-phase inverter circuit includes:

acquiring each phase voltage, each phase current and each filter capacitor current on the alternating current side based on the three-phase inverter circuit;

carrying out park transformation on each phase voltage, each phase current and each filter capacitor current at the alternating current side of the three-phase inverter circuit based on a preset alternating current angular frequency reference value and a park transformation method at the alternating current side of the three-phase inverter circuit so as to obtain a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component and a filter capacitor current q-axis component;

calculating reactive power based on the voltage d-axis component, the voltage q-axis component, the current d-axis component, the current q-axis component, and equation (1);

the formula (1) is specifically:

wherein Q is the above reactive power, U_qFor the d-axis component of the voltage, U_dFor the q-axis component of the voltage, I_gdFor the d-axis component of the current, I_gqIs the above-mentioned current q-axis component;

subtracting a preset reactive power reference value from the reactive power to obtain a ninth value;

as shown in fig. 4, U_refFor presetting grid-connected point voltage reference value, U_dFor the d-axis component of the voltage, I_fdIs the d-axis component of the filter capacitor current;

subtracting the ninth value of a preset multiple from the preset grid-connected point voltage reference value to obtain a tenth value;

subtracting the d-axis component of the voltage from the tenth value to obtain an eleventh value;

performing integral proportional operation on the eleventh value based on a fifth preset PI controller to obtain a twelfth value;

subtracting the d-axis component of the filter capacitor current from the twelfth value to obtain a thirteenth value;

performing integral proportional operation on the thirteenth value based on a sixth preset PI controller to obtain a fourteenth value;

as shown in fig. 4, U_qFor the above-mentioned q-axis component of the voltage, I_fqIs the q-axis component of the filter capacitor current;

subtracting the q-axis component of the voltage from 0 to obtain a fifteenth value;

performing integral proportion operation on the fifteenth value based on a seventh preset PI controller to obtain a sixteenth value;

subtracting the q-axis component of the filter capacitor current from the sixteenth value to obtain a seventeenth value;

performing integral proportional operation on the seventeenth value based on an eighth preset PI controller to obtain an eighteenth value;

performing inverse park transform on the fourteenth value and the eighteenth value based on an inverse park transform method to obtain a first voltage value, a second voltage value and a third voltage value;

generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal

Specifically, the park transformation is performed on each phase voltage, each phase current, and each filter capacitor current at the ac side of the three-phase inverter circuit based on the preset ac angular frequency reference value and the park transformation method at the ac side of the three-phase inverter circuit to obtain a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component, and a filter capacitor current q-axis component, and specifically includes:

calculating a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component, and a filter capacitor current q-axis component based on the voltages, the phases, the filter capacitor currents, equations (5), (6), (7), and (8) of the ac side of the three-phase inverter circuit;

the formulae (5), (6), (7) and (8) are specifically:

ω＝ω_ref (5)

amount u_a、u_bAnd u_cFor each phase voltage at the AC side of the three-phase inverter circuit, I_gdFor the d-axis component of the current, I_gqFor the above-mentioned q-axis component of the current, i_ga、i_gbAnd i_gcFor each phase current on the AC side of the three-phase inverter circuit, I_fdFor the d-axis component of the filter capacitor current, I_fqFor the q-axis component of the filter capacitor current, i_fa、i_fbAnd i_fcThe filter capacitor currents are respectively on the alternating current side of the three-phase inverter circuit.

Furthermore, the three pairs of push-pull switch tubes comprise: the first pair of push-pull switch tubes, the second pair of push-pull switch tubes and the third pair of push-pull switch tubes, the first pair of push-pull switch tubes comprises: a first push-pull switch tube and a second push-pull switch tube, wherein the second pair of push-pull switch tubes comprises: a third push-pull switch tube and a fourth push-pull switch tube, wherein the third pair of push-pull switch tubes comprises: the negative electrode of the first push-pull switching tube, the negative electrode of the third push-pull switching tube and the negative electrode of the fifth switching tube are used for respectively outputting alternating current of each phase with three alternating currents;

the second control signal includes: a first PWM control signal, a second PWM control signal, and a third PWM control signal;

the generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal includes:

calculating a nineteenth value, a twentieth value, and a twenty-first value based on the first voltage value, the second voltage value, the third voltage value, equation (2), equation (3), and equation (4);

the formula (2), the formula (3), and the formula (4) are each specifically:

wherein D is₁Is the above nineteenth value, D₂Is the twentieth value, D₃Is the second eleventh value, U_dcThe voltage on the dc side of the three-phase inverter circuit,in order to achieve the first voltage value mentioned above,the second voltage value is a value of the second voltage,the third voltage value;

PWM modulating the nineteenth, twentieth, and twenty-first values with a preset carrier, respectively, to generate the first, second, and third PWM control signals;

controlling the first push-pull switch tube based on the first PWM control signal, and controlling the second push-pull switch tube based on a control signal complementary to the first PWM control signal;

controlling the third push-pull switch tube based on the second PWM control signal, and controlling the fourth push-pull switch tube based on a control signal complementary to the second PWM control signal;

and controlling the fifth push-pull switching tube based on the third PWM control signal, and controlling the sixth push-pull switching tube based on a control signal complementary to the third PWM control signal.

From the above, the technical scheme of the application includes that on the basis of the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and more than one PI controller are used for controlling the on-off of a switch tube in the boost conversion circuit; the on-off of a switching tube in the three-phase inverter circuit is controlled based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method of the alternating current side of the three-phase inverter circuit and more than one PI controller. According to the technical scheme, all items of data acquired in the three-phase photovoltaic inverter circuit can be processed to obtain a plurality of control signals, and then all switch tubes in the three-phase photovoltaic inverter circuit are controlled based on the plurality of control signals, so that the technical effect that a photovoltaic system comprising the three-phase photovoltaic inverter circuit can be maintained to be stable without using energy storage equipment is achieved, and the operation cost of the photovoltaic system is reduced.

Example two

The application provides a be applied to three-phase photovoltaic inverter circuit's controlling means, above-mentioned three-phase photovoltaic inverter circuit is including step-up converting circuit and three-phase inverter circuit, above-mentioned step-up converting circuit's input be used for with photovoltaic power generation power electric connection, as shown in fig. 5, controlling means 50 includes:

a first control unit 501, configured to control on/off of a switching tube in the boost converter circuit based on a voltage, a current, a preset voltage reference value on a dc side of the three-phase inverter circuit, a photovoltaic output power and a photovoltaic output voltage of the photovoltaic power generation power supply, and one or more PI controllers;

a second control unit 502, configured to control on/off of a switching tube in the three-phase inverter circuit based on a preset ac angular frequency reference value on an ac side of the three-phase inverter circuit, each phase voltage, each phase current, each filter capacitor current, a park transformation method, and a park inverse transformation method, and one or more PI controllers.

Optionally, the first control unit 501 is specifically configured to:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

based on a second preset PI controller, performing integral proportion operation on the third value to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

Optionally, the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which are in one-to-one correspondence with the push-pull branches, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current of each filter capacitor;

the second control unit 502 is specifically configured to:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

Further, the second control unit 502 is specifically configured to:

acquiring each phase voltage, each phase current and each filter capacitor current on the alternating current side based on the three-phase inverter circuit;

carrying out park transformation on each phase voltage, each phase current and each filter capacitor current at the alternating current side of the three-phase inverter circuit based on a preset alternating current angular frequency reference value and a park transformation method at the alternating current side of the three-phase inverter circuit so as to obtain a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component and a filter capacitor current q-axis component;

calculating reactive power based on the voltage d-axis component, the voltage q-axis component, the current d-axis component, the current q-axis component, and equation (1);

the formula (1) is specifically:

wherein Q is the above reactive power, U_qFor the d-axis component of the voltage, U_dFor the q-axis component of the voltage, I_gdFor the d-axis component of the current, I_gqIs the above-mentioned current q-axis component;

subtracting a preset reactive power reference value from the reactive power to obtain a ninth value;

subtracting the ninth value of the preset multiple from the preset grid-connected point voltage reference value to obtain a tenth value;

subtracting the d-axis component of the voltage from the tenth value to obtain an eleventh value;

performing integral proportional operation on the eleventh value based on a fifth preset PI controller to obtain a twelfth value;

subtracting the d-axis component of the filter capacitor current from the twelfth value to obtain a thirteenth value;

performing integral proportional operation on the thirteenth value based on a sixth preset PI controller to obtain a fourteenth value;

subtracting the q-axis component of the voltage from 0 to obtain a fifteenth value;

performing integral proportion operation on the fifteenth value based on a seventh preset PI controller to obtain a sixteenth value;

subtracting the q-axis component of the filter capacitor current from the sixteenth value to obtain a seventeenth value;

performing integral proportional operation on the seventeenth value based on an eighth preset PI controller to obtain an eighteenth value;

performing inverse park transform on the fourteenth value and the eighteenth value based on an inverse park transform method to obtain a first voltage value, a second voltage value and a third voltage value;

generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal

Furthermore, the three pairs of push-pull switch tubes comprise: the first pair of push-pull switch tubes, the second pair of push-pull switch tubes and the third pair of push-pull switch tubes, the first pair of push-pull switch tubes comprises: a first push-pull switch tube and a second push-pull switch tube, wherein the second pair of push-pull switch tubes comprises: a third push-pull switch tube and a fourth push-pull switch tube, wherein the third pair of push-pull switch tubes comprises: the negative electrode of the first push-pull switching tube, the negative electrode of the third push-pull switching tube and the negative electrode of the fifth switching tube are used for respectively outputting alternating current of each phase with three alternating currents;

the second control signal includes: a first PWM control signal, a second PWM control signal, and a third PWM control signal;

the second control unit 502 is specifically configured to:

calculating a nineteenth value, a twentieth value, and a twenty-first value based on the first voltage value, the second voltage value, the third voltage value, equation (2), equation (3), and equation (4);

the formula (2), the formula (3), and the formula (4) are each specifically:

wherein D is₁Is the above nineteenth value, D₂Is the twentieth value, D₃Is the second eleventh value, U_dcThe voltage on the dc side of the three-phase inverter circuit,in order to achieve the first voltage value mentioned above,the second voltage value is a value of the second voltage,the third voltage value;

PWM modulating the nineteenth, twentieth, and twenty-first values with a preset carrier, respectively, to generate the first, second, and third PWM control signals;

controlling the first push-pull switch tube based on the first PWM control signal, and controlling the second push-pull switch tube based on a control signal complementary to the first PWM control signal;

controlling the third push-pull switch tube based on the second PWM control signal, and controlling the fourth push-pull switch tube based on a control signal complementary to the second PWM control signal;

and controlling the fifth push-pull switching tube based on the third PWM control signal, and controlling the sixth push-pull switching tube based on a control signal complementary to the third PWM control signal.

From the above, the technical scheme of the application includes that on the basis of the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and more than one PI controller are used for controlling the on-off of a switch tube in the boost conversion circuit; the on-off of a switching tube in the three-phase inverter circuit is controlled based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method of the alternating current side of the three-phase inverter circuit and more than one PI controller. According to the technical scheme, all items of data acquired in the three-phase photovoltaic inverter circuit can be processed to obtain a plurality of control signals, and then all switch tubes in the three-phase photovoltaic inverter circuit are controlled based on the plurality of control signals, so that the technical effect that a photovoltaic system comprising the three-phase photovoltaic inverter circuit can be maintained to be stable without using energy storage equipment is achieved, and the operation cost of the photovoltaic system is reduced.

EXAMPLE III

This application still provides another kind of controlling means who is applied to three-phase photovoltaic inverter circuit, and above-mentioned three-phase photovoltaic inverter circuit includes boost converter circuit and three-phase inverter circuit, and above-mentioned boost converter circuit's input is used for with photovoltaic power generation power electric connection, as shown in fig. 6, controlling means in this application embodiment includes: a memory 601, a processor 602, and a computer program stored in the memory 601 and executable on the processor 602, wherein: the memory 601 is used to store software programs and modules, the processor 602 executes various functional applications and data processing by operating the software programs and modules stored in the memory 601, and the memory 601 and the processor 602 are connected by a bus 603.

Specifically, the processor 602 implements the following steps by executing the above computer program stored in the memory 601:

controlling the on-off of a switching tube in the boost conversion circuit based on the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply and more than one PI controller;

and controlling the on-off of a switching tube in the three-phase inverter circuit based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

In a second possible implementation manner based on the first possible implementation manner, the controlling the on/off of the switching tube in the boost converter circuit based on the voltage, the current, and the preset voltage reference value on the dc side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and one or more PI controllers includes:

acquiring voltage and current of a direct current side of the three-phase inverter circuit, and photovoltaic output power and photovoltaic output voltage of the photovoltaic power generation power supply;

subtracting the voltage at the direct current side of the three-phase inverter circuit from the preset voltage reference value at the direct current side of the three-phase inverter circuit to obtain a first value;

based on a first preset PI controller, performing integral proportional operation on the first value to obtain a second value;

subtracting the photovoltaic output power of the photovoltaic power generation power supply from the second value to obtain a third value;

based on a second preset PI controller, performing integral proportion operation on the third value to obtain a fourth value;

subtracting the fourth value from the photovoltaic output voltage of the photovoltaic power generation power supply to obtain a fifth value;

performing integral proportional operation on the fifth value based on a third preset PI controller to obtain a sixth value;

subtracting the current on the direct current side of the three-phase inverter circuit from the sixth value to obtain a seventh value;

performing integral proportion operation on the seventh value based on a fourth preset PI controller to obtain an eighth value;

and generating a first control signal based on the eighth value, and controlling the on-off of a switch tube in the boost conversion circuit based on the first control signal.

In a third possible implementation manner based on the first or second possible implementation manner, the three-phase conversion circuit includes: the filter circuit comprises three parallel push-pull branches and filter capacitors which are in one-to-one correspondence with the push-pull branches, wherein each push-pull branch consists of two switch tubes which are connected in series, and the current of each filter capacitor is the current on each filter capacitor;

the above preset ac angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, park transformation method, park inverse transformation method based on the ac side of the above three-phase inverter circuit, and one or more PI controllers, the controlling the on/off of the switching tube in the above three-phase inverter circuit includes:

and controlling the on-off of the switching tubes in the three parallel push-pull branches based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method on the alternating current side of the three-phase inverter circuit and more than one PI controller.

In a fourth possible implementation manner based on the third possible implementation manner, the controlling the on/off of the switching tubes in the three parallel push-pull branches based on the preset ac angular frequency reference value on the ac side of the three-phase inverter circuit, the voltage of each phase, the current of each filter capacitor, the park transformation method, the park inverse transformation method, and one or more PI controllers includes:

acquiring each phase voltage, each phase current and each filter capacitor current on the alternating current side based on the three-phase inverter circuit;

carrying out park transformation on each phase voltage, each phase current and each filter capacitor current at the alternating current side of the three-phase inverter circuit based on a preset alternating current angular frequency reference value and a park transformation method at the alternating current side of the three-phase inverter circuit so as to obtain a voltage d-axis component, a voltage q-axis component, a current d-axis component, a current q-axis component, a filter capacitor current d-axis component and a filter capacitor current q-axis component;

calculating reactive power based on the voltage d-axis component, the voltage q-axis component, the current d-axis component, the current q-axis component, and equation (1);

the formula (1) is specifically:

wherein Q is the above reactive power, U_qFor the d-axis component of the voltage, U_dFor the q-axis component of the voltage, I_gdFor the d-axis component of the current, I_gqIs the above-mentioned current q-axis component;

subtracting a preset reactive power reference value from the reactive power to obtain a ninth value;

subtracting the ninth value of the preset multiple from the preset grid-connected point voltage reference value to obtain a tenth value;

subtracting the d-axis component of the voltage from the tenth value to obtain an eleventh value;

performing integral proportional operation on the eleventh value based on a fifth preset PI controller to obtain a twelfth value;

subtracting the d-axis component of the filter capacitor current from the twelfth value to obtain a thirteenth value;

performing integral proportional operation on the thirteenth value based on a sixth preset PI controller to obtain a fourteenth value;

subtracting the q-axis component of the voltage from 0 to obtain a fifteenth value;

performing integral proportion operation on the fifteenth value based on a seventh preset PI controller to obtain a sixteenth value;

subtracting the q-axis component of the filter capacitor current from the sixteenth value to obtain a seventeenth value;

performing integral proportional operation on the seventeenth value based on an eighth preset PI controller to obtain an eighteenth value;

performing inverse park transform on the fourteenth value and the eighteenth value based on an inverse park transform method to obtain a first voltage value, a second voltage value and a third voltage value;

generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal

In a fifth possible implementation manner based on the fourth possible implementation manner, the three pairs of push-pull switching tubes include: the first pair of push-pull switch tubes, the second pair of push-pull switch tubes and the third pair of push-pull switch tubes, the first pair of push-pull switch tubes comprises: a first push-pull switch tube and a second push-pull switch tube, wherein the second pair of push-pull switch tubes comprises: a third push-pull switch tube and a fourth push-pull switch tube, wherein the third pair of push-pull switch tubes comprises: a fifth push-pull switching tube and a sixth push-pull switching tube, wherein the negative electrode of the first push-pull switching tube, the negative electrode of the third push-pull switching tube and the negative electrode of the fifth switching tube are used for respectively outputting each phase alternating current of three-phase alternating current;

the second control signal includes: a first PWM control signal, a second PWM control signal, and a third PWM control signal;

the generating a second control signal based on the first voltage value, the second voltage value, and the third voltage value, and controlling the three pairs of push-pull switching tubes based on the second control signal includes:

calculating a nineteenth value, a twentieth value, and a twenty-first value based on the first voltage value, the second voltage value, the third voltage value, equation (2), equation (3), and equation (4);

the formula (2), the formula (3), and the formula (4) are each specifically:

wherein D is₁Is the above nineteenth value, D₂₂Is the twentieth value, D₃Is the second eleventh value, U_dcThe voltage on the dc side of the three-phase inverter circuit,in order to achieve the first voltage value mentioned above,the second voltage value is a value of the second voltage,is that the above-mentionedA third voltage value;

PWM modulating the nineteenth, twentieth, and twenty-first values with a preset carrier, respectively, to generate the first, second, and third PWM control signals;

controlling the first push-pull switch tube based on the first PWM control signal, and controlling the second push-pull switch tube based on a control signal complementary to the first PWM control signal;

controlling the third push-pull switch tube based on the second PWM control signal, and controlling the fourth push-pull switch tube based on a control signal complementary to the second PWM control signal;

and controlling the fifth push-pull switching tube based on the third PWM control signal, and controlling the sixth push-pull switching tube based on a control signal complementary to the third PWM control signal.

From the above, the technical scheme of the application includes that on the basis of the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and more than one PI controller are used for controlling the on-off of a switch tube in the boost conversion circuit; the on-off of a switching tube in the three-phase inverter circuit is controlled based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method of the alternating current side of the three-phase inverter circuit and more than one PI controller. According to the technical scheme, all items of data acquired in the three-phase photovoltaic inverter circuit can be processed to obtain a plurality of control signals, and then all switch tubes in the three-phase photovoltaic inverter circuit are controlled based on the plurality of control signals, so that the technical effect that a photovoltaic system comprising the three-phase photovoltaic inverter circuit can be maintained to be stable without using energy storage equipment is achieved, and the operation cost of the photovoltaic system is reduced.

Example four

The present application also provides a computer readable storage medium having a computer program stored thereon, which when executed, can implement the steps provided by the above-described embodiments. In particular, the computer program includes computer program code, which may be in one of a source code form, an object code form, an executable file or some intermediate form, and is not limited herein; the computer readable storage medium can be any entity or device capable of carrying the above computer program code, a recording medium, a usb disk, a removable hard disk, a magnetic disk, an optical disk, a computer Memory, a Read-Only Memory (ROM), a Random Access Memory (RAM), an electrical carrier signal, a telecommunications signal, and a software distribution medium, and is not limited thereto. It should be noted that the contents contained in the computer-readable storage medium can be increased or decreased as required by legislation and patent practice in the jurisdiction.

From the above, the technical scheme of the application includes that on the basis of the voltage, the current and the preset voltage reference value of the direct current side of the three-phase inverter circuit, the photovoltaic output power and the photovoltaic output voltage of the photovoltaic power generation power supply, and more than one PI controller are used for controlling the on-off of a switch tube in the boost conversion circuit; the on-off of a switching tube in the three-phase inverter circuit is controlled based on a preset alternating current angular frequency reference value, each phase voltage, each phase current, each filter capacitor current, a park transformation method and a park inverse transformation method of the alternating current side of the three-phase inverter circuit and more than one PI controller. According to the technical scheme, all items of data acquired in the three-phase photovoltaic inverter circuit can be processed to obtain a plurality of control signals, and then all switch tubes in the three-phase photovoltaic inverter circuit are controlled based on the plurality of control signals, so that the technical effect that a photovoltaic system comprising the three-phase photovoltaic inverter circuit can be maintained to be stable without using energy storage equipment is achieved, and the operation cost of the photovoltaic system is reduced.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-mentioned division of the functional units and modules is illustrated, and in practical applications, the above-mentioned functions may be distributed as different functional units and modules according to needs, that is, the internal structure of the apparatus may be divided into different functional units or modules to implement all or part of the above-mentioned functions. Each functional unit and module in the embodiments may be integrated in one processing unit, or each unit may exist alone physically, or two or more units are integrated in one unit, and the integrated unit may be implemented in a form of hardware, or in a form of software functional unit. In addition, specific names of the functional units and modules are only for convenience of distinguishing from each other, and are not used to limit the scope of protection of the present application. The specific working processes of the units and modules in the system may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

It should be noted that, the methods and the details thereof provided by the foregoing embodiments may be combined with the apparatuses and devices provided by the embodiments, which are referred to each other and are not described again.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be implemented as electronic hardware, or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus/terminal device and method may be implemented in other ways. For example, the above-described apparatus/device embodiments are merely illustrative, and for example, the division of the above-described modules or units is only one logical functional division, and the actual implementation may be implemented by another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed.

The above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not substantially depart from the spirit and scope of the embodiments of the present application and are intended to be included within the scope of the present application.