Multi-channel photovoltaic optimizer and photovoltaic power generation system

Abstract

The invention discloses a multi-channel photovoltaic optimizer and a photovoltaic power generation system, the photovoltaic power generation system at least comprises a first photovoltaic module, a second photovoltaic module and an inverter, the multi-channel photovoltaic optimizer comprises a first half-bridge circuit, a first inductor and a first capacitor, the first half-bridge circuit is connected in parallel with the first photovoltaic module, and the first inductor is connected in parallel with the second photovoltaic module. Two ends of the first inductor are respectively connected to a bridge arm midpoint of the first half-bridge circuit and one end of the first capacitor, the other end of the first capacitor is connected with a positive electrode of the first photovoltaic module, and the first capacitor is also connected to the inverter; the second half-bridge circuit is connected with the second photovoltaic module in parallel, the two ends of the second inductor are connected to the midpoint of a bridge arm of the second half-bridge circuit and one end of the second capacitor respectively, the other end of the second capacitor is connected with the negative electrode of the second photovoltaic module, and the second capacitor is further connected to the inverter. Through the arrangement, the number of the photovoltaic modules connected with the multi-channel photovoltaic optimizer is increased.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic power generation technology, and in particular to a multi-channel photovoltaic optimizer and a photovoltaic power generation system. Background Art

[0002] A photovoltaic module is a single photovoltaic panel made up of several single solar cells connected in series and parallel and tightly sealed. The output power of a photovoltaic module is usually within a few hundred watts. In a photovoltaic array, a single photovoltaic module is often affected by the surrounding environment (clouds in the sky, trees, high-rise buildings, dust), resulting in uneven light intensity in the photovoltaic array and local shading problems. In order to solve the problems of photovoltaic module mismatch and local shading, each photovoltaic module is usually connected in parallel with a photovoltaic optimizer with maximum power tracking control technology, and multiple photovoltaic optimizers are connected in series and then connected to the DC input of the inverter. In order to further reduce system costs, multiple photovoltaic modules are usually connected to one optimizer to form a multi-channel photovoltaic optimizer.

[0003] The existing multi-channel photovoltaic optimizer is simply a series connection of single-channel photovoltaic optimizers, which results in the inability to connect more photovoltaic modules to the existing multi-channel photovoltaic optimizer. Summary of the invention

[0004] In order to address the deficiencies of the prior art, the purpose of the present application is to provide a multi-channel photovoltaic optimizer and a photovoltaic power generation system that can connect more photovoltaic modules.

[0005] To achieve the above objectives, this application adopts the following technical solutions:

[0006] The present application provides a multi-channel photovoltaic optimizer, which is applied to a photovoltaic power generation system. The photovoltaic power generation system at least includes a first photovoltaic component, a second photovoltaic component and an inverter. The multi-channel photovoltaic optimizer includes:

[0007] A first optimization circuit, the first optimization circuit comprising a first half-bridge circuit, a first inductor and a first capacitor, the first half-bridge circuit being connected in parallel with the first photovoltaic component, two ends of the first inductor being respectively connected to a midpoint of a bridge arm of the first half-bridge circuit and one end of the first capacitor, the other end of the first capacitor being connected to a positive electrode of the first photovoltaic component, and the first capacitor being further connected to an input end of an inverter;

[0008] A second optimization circuit, the second optimization circuit includes a second half-bridge circuit, a second inductor and a second capacitor, the second half-bridge circuit is connected in parallel with the second photovoltaic component, two ends of the second inductor are respectively connected to the midpoint of the bridge arm of the second half-bridge circuit and one end of the second capacitor, the other end of the second capacitor is connected to the negative electrode of the second photovoltaic component, and the second capacitor is also connected to the input end of the inverter;

[0009] Among them, the first optimization circuit is used to obtain the output voltage of the first photovoltaic component, and adjust the output voltage of the first photovoltaic component to control the first photovoltaic component to operate at the maximum power point, and the first optimization circuit is also used to couple the output voltage of the first photovoltaic component to the input end of the inverter; the second optimization circuit is used to obtain the output voltage of the second photovoltaic component, and adjust the output voltage of the second photovoltaic component to control the second photovoltaic component to operate at the maximum power point, and the second optimization circuit is also used to couple the output voltage of the second photovoltaic component to the input end of the inverter.

[0010] Furthermore, there are multiple first optimization circuits, and two ends of each first optimization circuit are respectively connected to a photovoltaic component and an inverter, wherein the output ends of the multiple first optimization circuits are connected in series.

[0011] Furthermore, the first half-bridge circuit includes a first switch tube and a second switch tube, wherein two ends of the first switch tube are respectively connected to the positive pole of the first photovoltaic component and one end of the second switch tube, and the other end of the second switch tube is connected to the negative pole of the first photovoltaic component, wherein the common end of the first switch tube and the second switch tube is the midpoint of the bridge arm of the first half-bridge circuit.

[0012] Furthermore, the second half-bridge circuit includes a third switch tube and a fourth switch tube, wherein two ends of the third switch tube are respectively connected to the positive pole of the second photovoltaic component and one end of the fourth switch tube, and the other end of the fourth switch tube is connected to the negative pole of the second photovoltaic component, wherein the common end of the third switch tube and the fourth switch tube is the midpoint of the bridge arm of the second half-bridge circuit.

[0013] Furthermore, the multi-channel photovoltaic optimizer also includes a control unit, which is connected to the control end of the first switch tube, the control end of the second switch tube, the control end of the third switch tube and the control end of the fourth switch tube; the control unit is used to control the conduction duty cycle of the first switch tube and the second switch tube to adjust the output voltage of the first photovoltaic component, and the control unit is also used to control the conduction duty cycle of the third switch tube and the fourth switch tube to adjust the output voltage of the second photovoltaic component.

[0014] Further, the control unit controls the on-duty cycle of the second switch tube to adjust the output voltage of the first photovoltaic assembly, and the control unit controls the on-duty cycle of the third switch tube to adjust the output voltage of the second photovoltaic assembly. The input voltage of the inverter, the on-duty cycle of the second switch tube, the output voltage of the first photovoltaic assembly, the on-duty cycle of the third switch tube, and the output voltage of the second photovoltaic assembly satisfy the following relationship:

[0015] V out =D1×V in1 +D2×V in2

[0016] Where V outis the input voltage of the inverter, D1 is the conduction duty cycle of the second switch tube, V in1 is the output voltage of the first photovoltaic module, D2 is the conduction duty cycle of the third switch tube, V in2 is the output voltage of the second photovoltaic module.

[0017] Furthermore, a phase difference between the control signal of the second switch tube and the control signal of the third switch tube is greater than or equal to 120° and less than or equal to 240°.

[0018] Furthermore, the first switch tube, the second switch tube, the third switch tube and the fourth switch tube are all power switch devices.

[0019] Furthermore, the first switch tube and the fourth switch tube are both power diodes, and the second switch tube and the third switch tube are power switch devices.

[0020] The present application also provides a photovoltaic power generation system, which includes the multi-channel photovoltaic optimizer mentioned above.

[0021] The above-mentioned multi-channel photovoltaic optimizer increases the number of photovoltaic components connected to the multi-channel photovoltaic optimizer by setting a first half-bridge circuit, a second half-bridge circuit, a first inductor and a first capacitor, and connecting the two ends of the first inductor to the midpoint of the bridge arm of the first half-bridge circuit and one end of the first capacitor respectively, and the other end of the first capacitor is connected to the positive electrode of the first photovoltaic component, and the two ends of the second inductor are connected to the midpoint of the bridge arm of the second half-bridge circuit and one end of the second capacitor respectively, and the other end of the second capacitor is connected to the negative electrode of the second photovoltaic component. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the structure of a photovoltaic power generation system and a multi-channel photovoltaic optimizer in an embodiment of the present application;

[0023] Figure 2 This is a circuit topology diagram of a multi-channel photovoltaic optimizer in an embodiment of the present application;

[0024] Figure 3 A circuit topology diagram of multiple first optimization circuits in the implementation mode of the present application

[0025] Figure 4 A circuit topology diagram when the first switch tube and the fourth switch tube are diodes in an embodiment of the present application;

[0026] Figure 5 4 is a control signal waveform diagram of the switch tube in the implementation manner of the present application. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the solution of the present application, the technical solution in the specific implementation manner of the present application will be clearly and completely described below in conjunction with the drawings in the implementation manner of the present application.

[0028] Unless otherwise defined, the technical terms or scientific terms involved in this application should be understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "a", "a", "the" and the like involved in this application do not indicate a quantitative limitation and may represent the singular or plural. The terms "include", "comprise", "have" and any of their variations involved in this application are intended to cover non-exclusive inclusions. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "multiple" involved in this application refers to greater than or equal to two. "And / or" describes the association relationship of associated objects, indicating that there may be three relationships, for example, "A and / or B" may represent: A exists alone, A and B exist at the same time, and B exists alone. The terms "first", "second", "third" and the like involved in this application are merely to distinguish similar objects and do not represent a specific ordering of objects.

[0029] like Figure 1 As shown, the present application provides a photovoltaic power generation system 200 and a multi-channel photovoltaic optimizer 100, the photovoltaic power generation system 200 includes a multi-channel photovoltaic optimizer 100, and the multi-channel photovoltaic optimizer 100 is applied to the photovoltaic power generation system 200. The photovoltaic power generation system 200 at least includes a first photovoltaic component 21, a second photovoltaic component 22 and an inverter 23, the input end of the multi-channel photovoltaic optimizer 100 is connected to the first photovoltaic component 21 and the second photovoltaic component 22, the output end of the multi-channel photovoltaic optimizer 100 is connected to the inverter 23, and the multi-channel photovoltaic optimizer 100 is used to control the first photovoltaic component 21 and the second photovoltaic component 21 to work at the maximum power point, thereby improving the power generation efficiency of the photovoltaic power generation system 200.

[0030] like Figure 2As shown, specifically, the dual-channel photovoltaic optimizer 100 includes a first optimization circuit 11 and a second optimization circuit 12. The first optimization circuit 11 includes a first half-bridge circuit 111, a first inductor L1 and a first capacitor C1. The first half-bridge circuit 111 is connected in parallel with the first photovoltaic component 21. The two ends of the first inductor L1 are respectively connected to the bridge arm midpoint N1 of the first half-bridge circuit 111 and one end of the first capacitor C1. The other end of the first capacitor C1 is connected to the positive electrode of the first photovoltaic component 21, and the first capacitor C1 is also connected to the input end of the inverter 23; the second optimization circuit 12 includes a second half-bridge circuit 121, a second inductor L2 and a second capacitor C2. The second half-bridge circuit 121 is connected in parallel with the second photovoltaic component 22. The two ends of the second inductor L2 are respectively connected to the bridge arm midpoint N2 of the second half-bridge circuit 121 and one end of the second capacitor C2. The other end of the second capacitor C2 is connected to the negative electrode of the second photovoltaic component 22, and the second capacitor C2 is also connected to the input end of the inverter 23. The first optimization circuit 11 is used to obtain the output voltage of the first photovoltaic component 21, the first optimization circuit 11 adjusts the output voltage of the first photovoltaic component 21 to control the first photovoltaic component 21 to work at the maximum power point, and the first optimization circuit 11 is also used to couple the output voltage of the first photovoltaic component 21 to the input end of the inverter 23; the second optimization circuit 12 is used to obtain the output voltage of the second photovoltaic component 22, the second optimization circuit 12 adjusts the output voltage of the second photovoltaic component 22 to control the second photovoltaic component 22 to work at the maximum power point, and the second optimization circuit 12 is also used to couple the output voltage of the second photovoltaic component 22 to the input end of the inverter 23. Through the above settings, the multi-channel photovoltaic optimizer 100 can control the first photovoltaic component 21 and the second photovoltaic component 22 to work at the maximum power point, thereby improving the power generation efficiency of the photovoltaic power generation system 200. In addition, through the above settings, the number of photovoltaic components connected to the multi-channel photovoltaic optimizer 100 can also be increased.

[0031] It should be noted that a first filter circuit 13 is formed between the first capacitor L1 and the first inductor C1, and a second filter circuit 14 is formed between the second capacitor L2 and the second inductor C2. The first filter circuit 13 is used to filter out the AC component and higher harmonics in the output voltage of the first photovoltaic assembly 21 after adjustment by the first half-bridge circuit 111, and couple the output voltage to the input end of the inverter 23; the second filter circuit 14 is used to filter out the AC component and higher harmonics in the output voltage of the second photovoltaic assembly 22 after adjustment by the second half-bridge circuit 121, and couple the output voltage to the input end of the inverter 23. Through the above settings, the stability of the output voltage of the first photovoltaic assembly 21 and the output voltage of the second photovoltaic assembly 22 is improved.

[0032] Specifically, the first filter capacitor C1 receives the output voltage of the first photovoltaic assembly 21 after adjustment by the first half-bridge circuit 111, and filters out the AC component in the output voltage. The first filter inductor L1 receives the output voltage of the first photovoltaic assembly 21 after adjustment by the first half-bridge circuit 111, and filters out the higher harmonics in the output voltage. The second filter capacitor C2 receives the output voltage of the second photovoltaic assembly 22 after adjustment by the second half-bridge circuit 121, and filters out the AC component in the output voltage. The second filter inductor L2 receives the output voltage of the second photovoltaic assembly 22 after adjustment by the second half-bridge circuit 121, and filters out the higher harmonics in the output voltage.

[0033] like Figure 3 As shown, as an implementation, the number of first optimization circuits 11 can be set to multiple, each first optimization circuit 11 is respectively connected to a photovoltaic module and an inverter 23, wherein the output ends of multiple first optimization circuits 11 are connected in series. It can be understood that when the photovoltaic power generation system 200 needs to increase the number of photovoltaic modules, the number of photovoltaic modules connected to the photovoltaic power generation system 200 can be increased by increasing the number of first optimization circuits 11 and connecting each first optimization circuit 11 to a photovoltaic module.

[0034] like Figure 2 As shown, as an implementation, the first half-bridge circuit 111 includes a first switch tube Q1 and a second switch tube Q2, the two ends of the first switch tube Q1 are respectively connected to the positive electrode of the first photovoltaic component 21 and one end of the second switch tube Q2, and the other end of the second switch tube Q2 is connected to the negative electrode of the first photovoltaic component 21, wherein the common end of the first switch tube Q1 and the second switch tube Q2 is the bridge arm midpoint N1 of the first half-bridge circuit 111. The first switch tube Q1 and the second switch tube Q2 are complementary to each other, thereby avoiding the first switch tube Q1 and the second switch tube Q2 being turned on at the same time to cause a short circuit in the first photovoltaic component 21.

[0035] Furthermore, the second half-bridge circuit 121 includes a third switch tube Q3 and a fourth switch tube Q4, wherein two ends of the third switch tube Q3 are respectively connected to the positive pole of the second photovoltaic component 22 and one end of the fourth switch tube Q4, and the other end of the fourth switch tube Q4 is connected to the negative pole of the second photovoltaic component 22, wherein the common end of the third switch tube Q3 and the fourth switch tube Q4 is the midpoint N2 of the bridge arm of the second half-bridge circuit 121.

[0036] As an implementation, the multi-channel photovoltaic optimizer 100 further includes a control unit (not shown), which is connected to the control end of the first switch tube Q1, the control end of the second switch tube Q2, the control end of the third switch tube Q3, and the control end of the fourth switch tube Q4, wherein the control unit is an MCU (Microcontroller Unit) or a CPU (Central Processing Unit), etc. The control unit is used to control the conduction time of the first switch tube Q1 and the second switch tube Q2 to adjust the output voltage of the first photovoltaic assembly 21, and the control unit is also used to control the conduction time of the third switch tube Q3 and the fourth switch tube Q4 to adjust the output voltage of the second photovoltaic assembly 22.

[0037] Specifically, the second switch tube Q2 receives the output voltage of the first photovoltaic assembly 21, and the control unit controls the on-duty ratio of the second switch tube Q2 (the on-time of the second switch tube Q2 divided by the switching period of the second switch tube Q2) to adjust the output voltage of the first photovoltaic assembly 21; the third switch tube Q3 receives the output voltage of the second photovoltaic assembly 22, and the control unit controls the on-duty ratio of the third switch tube Q3 to adjust the output voltage of the second photovoltaic assembly 22. The input voltage of the inverter 23, the on-duty ratio of the second switch tube Q2, the output voltage of the first photovoltaic assembly 21, the on-duty ratio of the third switch tube Q3, and the output voltage of the second photovoltaic assembly 22 satisfy the following relationship:

[0038] V out =D1×V in1 +D2×V in2

[0039] Where V out is the input voltage of the inverter 23, D1 is the conduction duty cycle of the second switch tube Q2, V in1 is the output voltage of the first photovoltaic assembly 21, D2 is the conduction duty cycle of the third switch tube Q3, V in2 is the output voltage of the second photovoltaic component 22 .

[0040] It can be understood that when the first photovoltaic assembly 21 is mismatched and partially blocked, the first photovoltaic assembly 21 does not work at the maximum power point. At this time, the control unit can reduce the output voltage of the first photovoltaic assembly 21 by reducing the conduction duty cycle of the second switch tube Q2, thereby controlling the first photovoltaic assembly 21 to work at the maximum power point again. When the second photovoltaic assembly 22 is mismatched and partially blocked, the second photovoltaic assembly 22 does not work at the maximum power point. At this time, the control unit can reduce the output voltage of the second photovoltaic assembly 22 by reducing the conduction duty cycle of the third switch tube Q3, thereby controlling the second photovoltaic assembly 22 to work at the maximum power point again. Through the above settings, the control unit can control the first photovoltaic assembly 21 and the second photovoltaic assembly 22 to work at the maximum power point, thereby improving the power generation efficiency of the photovoltaic power generation system 200.

[0041] like Figure 2 As shown, as an implementation method, the multi-channel photovoltaic optimizer 100 also includes a first energy storage capacitor Cin1 and a second energy storage capacitor Cin2, one end of the first energy storage capacitor Cin1 is connected to the positive electrode of the first photovoltaic component 21, and the other end of the first energy storage capacitor Cin1 is connected to the negative electrode of the first photovoltaic component 21. The first energy storage capacitor Cin1 receives the output voltage of the first photovoltaic component 21 and stores the electric energy output by the first photovoltaic component 21 in the capacitor of the first energy storage capacitor Cin1. When the first photovoltaic component 21 is mismatched and partially blocked, the control unit reduces the on-duty cycle of the first switch tube Q1, thereby reducing the output voltage of the first photovoltaic component 21. At this time, the first energy storage capacitor Cin1 can provide voltage to the first photovoltaic component 21, thereby preventing the output voltage of the first photovoltaic component 21 from decreasing too quickly, thereby improving the stability of the output voltage of the first photovoltaic component 21.

[0042] Furthermore, one end of the second energy storage capacitor Cin2 is connected to the positive electrode of the second photovoltaic assembly 22, and the other end of the second energy storage capacitor Cin2 is connected to the negative electrode of the second photovoltaic assembly 22. The second energy storage capacitor Cin2 receives the output voltage of the second photovoltaic assembly 22, and stores the electric energy output by the first photovoltaic assembly 22 in the capacitance of the second energy storage capacitor Cin2. When the second photovoltaic assembly 22 is mismatched and partially blocked, the control unit reduces the conduction duty cycle of the second switch tube Q2, thereby reducing the output voltage of the second photovoltaic assembly 22. At this time, the second energy storage capacitor Cin2 can provide voltage to the second photovoltaic assembly 22, thereby preventing the output voltage of the second photovoltaic assembly 22 from decreasing too quickly, thereby improving the stability of the output voltage of the second photovoltaic assembly 22.

[0043] It should be noted that, in the embodiment of the present application, the first switch tube Q1, the second switch tube Q2, the third switch tube Q3 and the fourth switch tube Q4 are all power switch devices such as metal-oxide semiconductor field effect transistors, gallium nitride field effect transistors, silicon carbide field effect transistors, insulated gate bipolar transistors, etc. Exemplarily, the first switch tube Q1, the second switch tube Q2, the third switch tube Q3 and the fourth switch tube Q4 are all metal-oxide semiconductor field effect transistors, the drain of the first switch tube Q1 is connected to the positive electrode of the first photovoltaic component 21, the drain of the second switch tube Q2 is connected to the source of the first switch tube Q1, and the source of the second switch tube Q2 is connected to the negative electrode of the first photovoltaic component 21. The drain of the third switch tube Q3 is connected to the positive electrode of the second photovoltaic component 22, the drain of the fourth switch tube Q4 is connected to the source of the third switch tube Q3, and the source of the fourth switch tube Q4 is connected to the negative electrode of the second photovoltaic component 22. The gate of the first switch tube Q1 , the gate of the second switch tube Q2 , the gate of the third switch tube Q3 , and the gate of the fourth switch tube Q4 are all connected to the control unit.

[0044] Optionally, the second switch tube Q2 and the third switch tube Q3 are both power switch devices such as metal-oxide semiconductor field effect transistors, gallium nitride field effect transistors, silicon carbide field effect transistors, insulated gate bipolar transistors, etc., and the first switch tube Q1 and the fourth switch tube Q4 are both power diodes such as at least one of Schottky diodes, fast recovery diodes, and silicon carbide diodes. Figure 4 As shown, illustratively, the second switch tube Q2 and the third switch tube Q3 are both metal-oxide semiconductor field effect transistors, and the first switch tube Q1 and the fourth switch tube Q4 are both Schottky diodes. The cathode of the first switch tube Q1 is connected to the anode of the first photovoltaic assembly 21, the cathode of the first switch tube Q1 is connected to the drain of the second switch tube Q2, and the source of the second switch tube Q2 is connected to the cathode of the first photovoltaic assembly 21. The drain of the third switch tube Q3 is connected to the anode of the second photovoltaic assembly 22, the source of the third switch tube Q3 is connected to the cathode of the fourth switch tube Q4, and the anode of the fourth switch tube Q4 is connected to the cathode of the second photovoltaic assembly 22. The gate of the first switch tube Q1 and the gate of the fourth switch tube Q4 are both connected to the control unit.

[0045] like Figure 5As shown, as an implementation method, the phase difference between the control signal of the second switch tube Q2 and the control signal of the third switch tube Q3 is greater than or equal to 120° and less than or equal to 240°. In the embodiment of the present application, the phase difference between the control signal of the second switch tube Q2 and the control signal of the third switch tube Q3 is 180°. It can be understood that the phase difference between the control signal of the second switch tube Q2 and the control signal of the third switch tube Q3 can also be 140° or 220°, etc. The control signals with a phase difference of greater than or equal to 120° and less than or equal to 240° are all within the protection range required by the present application. Through the above-mentioned setting, when the multi-channel photovoltaic optimizer 100 is started, the second switch tube Q2 and the third switch tube Q3 can be prevented from being turned on at the same time, thereby preventing the inverter 23 from receiving a large starting current and causing damage to the inverter 23, thereby improving the safety of the inverter 23.

[0046] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to this application.

Claims

1. A multi-channel photovoltaic optimizer, applied to a photovoltaic power generation system, wherein the photovoltaic power generation system comprises at least a first photovoltaic module, a second photovoltaic module and an inverter, characterized in that: The multi-channel photovoltaic optimizer comprises: a first optimization circuit, wherein the first optimization circuit comprises a first half-bridge circuit, a first inductor and a first capacitor, wherein the first half-bridge circuit is connected in parallel with the first photovoltaic component, two ends of the first inductor are respectively connected to a midpoint of a bridge arm of the first half-bridge circuit and one end of the first capacitor, the other end of the first capacitor is connected to a positive electrode of the first photovoltaic component, and the first capacitor is also connected to an input end of the inverter; a second optimization circuit, wherein the second optimization circuit comprises a second half-bridge circuit, a second inductor and a second capacitor, the second half-bridge circuit is connected in parallel with the second photovoltaic assembly, two ends of the second inductor are respectively connected to the midpoint of the bridge arm of the second half-bridge circuit and one end of the second capacitor, the other end of the second capacitor is connected to the negative electrode of the second photovoltaic assembly, and the second capacitor is also connected to the input end of the inverter; The first optimization circuit is used to obtain the output voltage of the first photovoltaic component, and adjust the output voltage of the first photovoltaic component to control the first photovoltaic component to operate at a maximum power point, and the first optimization circuit is also used to couple the output voltage of the first photovoltaic component to the input end of the inverter; the second optimization circuit is used to obtain the output voltage of the second photovoltaic component, and adjust the output voltage of the second photovoltaic component to control the second photovoltaic component to operate at a maximum power point, and the second optimization circuit is also used to couple the output voltage of the second photovoltaic component to the input end of the inverter.

2. The multi-channel photovoltaic optimizer according to claim 1, characterized in that: There are multiple first optimization circuits, and two ends of each first optimization circuit are respectively connected to a photovoltaic component and the inverter, wherein the output ends of multiple first optimization circuits are connected in series.

3. The multi-channel photovoltaic optimizer according to claim 1, characterized in that: The first half-bridge circuit includes a first switch tube and a second switch tube, wherein two ends of the first switch tube are respectively connected to the positive pole of the first photovoltaic component and one end of the second switch tube, and the other end of the second switch tube is connected to the negative pole of the first photovoltaic component, wherein the common end of the first switch tube and the second switch tube is the midpoint of the bridge arm of the first half-bridge circuit.

4. The multi-channel photovoltaic optimizer according to claim 3, characterized in that: The second half-bridge circuit includes a third switch tube and a fourth switch tube, wherein two ends of the third switch tube are respectively connected to the positive pole of the second photovoltaic component and one end of the fourth switch tube, and the other end of the fourth switch tube is connected to the negative pole of the second photovoltaic component, wherein the common end of the third switch tube and the fourth switch tube is the midpoint of the bridge arm of the second half-bridge circuit.

5. The multi-channel photovoltaic optimizer according to claim 4, characterized in that: The multi-channel photovoltaic optimizer also includes a control unit, which is connected to the control end of the first switch tube, the control end of the second switch tube, the control end of the third switch tube and the control end of the fourth switch tube; the control unit is used to control the conduction duty cycle of the first switch tube and the second switch tube to adjust the output voltage of the first photovoltaic component, and the control unit is also used to control the conduction duty cycle of the third switch tube and the fourth switch tube to adjust the output voltage of the second photovoltaic component.

6. The multi-channel photovoltaic optimizer according to claim 5, characterized in that: The control unit controls the on-duty cycle of the second switch tube to adjust the output voltage of the first photovoltaic assembly, and the control unit controls the on-duty cycle of the third switch tube to adjust the output voltage of the second photovoltaic assembly. The input voltage of the inverter, the on-duty cycle of the second switch tube, the output voltage of the first photovoltaic assembly, the on-duty cycle of the third switch tube and the output voltage of the second photovoltaic assembly satisfy the following relationship: In out =D1×H in1 +D2×V in2 Where V out is the input voltage of the inverter, D1 is the on-duty cycle of the second switch tube, V in1 is the output voltage of the first photovoltaic module, D2 is the conduction duty cycle of the third switch tube, V in2 is the output voltage of the second photovoltaic component.

7. The multi-channel photovoltaic optimizer according to claim 6, characterized in that: A phase difference between the control signal of the second switch tube and the control signal of the third switch tube is greater than or equal to 120° and less than or equal to 240°.

8. The multi-channel photovoltaic optimizer according to claim 4, characterized in that: The first switch tube, the second switch tube, the third switch tube and the fourth switch tube are all power switch devices.

9. The multi-channel photovoltaic optimizer according to claim 4, characterized in that: The first switch tube and the fourth switch tube are both power diodes, and the second switch tube and the third switch tube are power switch devices.

10. A photovoltaic power generation system, characterized in that: The photovoltaic power generation system comprises the multi-channel photovoltaic optimizer according to any one of claims 1-9.

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