Photovoltaic power generation wireless energy transmission system and supporting transmission method

Abstract

The present invention relates to the field of photovoltaic power generation wireless energy transmission devices, in particular to a photovoltaic power generation wireless energy transmission system and a supporting transmission method. It aims to solve the problem of low conversion efficiency of photovoltaic power generation wireless energy transmission in the prior art. The present invention successively includes a photovoltaic side circuit, a wireless energy transmission transmitting circuit, and a wireless energy transmission receiving circuit along the energy transmission direction; wherein, the photovoltaic side circuit includes a photovoltaic module and a synchronous boost DC-DC converter module, the wireless energy transmission transmitting circuit includes a full-bridge inverter circuit module and the first half of an LCC-S resonant compensation mechanism; the wireless energy transmission receiving circuit includes the second half of the LCC-S resonant compensation module, a diode rectifier circuit module, a synchronous buck DC-DC converter module, and an electrical load. The advantages are as follows: the conduction loss of the freewheeling diode is greatly reduced, thereby obtaining a higher energy conversion efficiency.

Description

Technical Field

[0001] The present invention relates to the field of wireless energy transmission system devices, and particularly to a photovoltaic power generation wireless energy transmission system and a supporting transmission method. Background Art

[0002] Nowadays, the development of large-scale photovoltaic power generation in China has the characteristics of diversification. In order to promote the implementation of the innovation-driven development strategy and the harmonious coexistence between humans and nature, China strongly supports the development of the photovoltaic industry, and launches "photovoltaic +", distributed power generation, photovoltaic poverty alleviation, and photovoltaic leader projects, promoting the progress of photovoltaic power generation technology, the upgrading of the industry, and the reduction of costs. The application of photovoltaic power generation can be seen in large-scale photovoltaic grid connection and small-scale ordinary electronic devices.

[0003] Wireless energy transmission technology is a popular technology at present, which can be seen everywhere in life and has a wide range of applications. Its characteristic is that the energy transmission adopts a non-contact method, so the wear rate of the device is low, the area occupied by the charging area is relatively small, and the saving of some line connections makes the charging device easier to maintain.

[0004] With the development of new energy technology and the application of wireless energy transmission technology in various industries, the combination of photovoltaic power generation and wireless energy transmission technologies has gradually attracted people's attention. The topology structure and its control strategy of the system affect the efficiency and stability of the system. Therefore, the energy conversion structure, its control algorithm, and implementation are particularly important.

[0005] In the publicly disclosed patent technology, in the patent technology named "Wireless Energy Transmission Receiving Circuit and Wireless Energy Transmission System Applying the Circuit" with the application number 201711037142.5, the disclosed wireless energy transmission receiving circuit broadens the load regulation range and improves the wireless energy receiving efficiency by using a reconfigurable rectifier with two working modes of full-wave rectifier and voltage multiplier, a pre-rectification regulator capable of adjusting the output size of the induced voltage, and a control unit. However, the applicant has found in years of work in this field that this technology is extremely inconvenient to adjust during the working process, and the energy conversion is not stable enough. Summary of the Invention

[0006] The technical problem to be solved by the present invention is to solve the problems of improving the energy conversion efficiency and stable operation of the existing photovoltaic power generation wireless energy transmission system, and provide a synchronous DC-DC converter, an LCC resonance topology, and an MPPT control method based on Lyapunov backstepping control with higher conversion efficiency and better control effect.

[0007] The specific solution of the present invention is:

[0008] Design a photovoltaic power generation wireless energy transmission system,

[0009] The energy transmission direction sequentially includes a photovoltaic side circuit, a wireless energy transmission transmitting circuit, and a wireless energy transmission receiving circuit; wherein, the photovoltaic side circuit includes a photovoltaic module and a synchronous boost DC-DC converter module; the wireless energy transmission transmitting circuit includes a full-bridge inverter circuit module and the first half of an LCC-S resonant compensation mechanism; the wireless energy transmission receiving circuit includes the second half of the LCC-S resonant compensation module, a diode rectifier circuit module, a synchronous buck DC-DC converter module, and an electrical load. The synchronous boost DC-DC converter module includes a first capacitor C1. One side of the first capacitor C1 is connected to a first inductor L1, and the other side of the first capacitor C1 is connected in parallel to a first NMOS transistor VT1, a second NMOS transistor VT2. The other ends of the first NMOS transistor VT1 and the second NMOS transistor VT2 are connected to both ends of a second capacitor C2 to form the synchronous boost DC-DC converter module.

[0010] In a specific implementation, the full-bridge inverter circuit module includes a third NMOS transistor VT3, a fourth NMOS transistor VT4, a fifth NMOS transistor VT5, and a sixth NMOS transistor VT6 that are bridged.

[0011] In a specific implementation, the first half of the LCC-S resonant compensation module is the transmitting end. At the transmitting end, a second inductor L2 is connected in series with a third capacitor C3, and a fourth capacitor C4 is connected in series with a third inductor L3 and then connected in parallel with the third capacitor C3. The second half of the LCC-S resonant compensation module includes the output side of the LCC-S resonant compensation structure. The output side of the LCC-S resonant compensation structure includes a fourth inductor L4 and a fifth capacitor C5. The fourth inductor L4 is connected in series with the fifth capacitor C5. The fourth inductor L4 is installed corresponding to the third inductor L3. The output side of the LCC-S resonant compensation structure is connected in parallel with a diode uncontrolled rectifier circuit. The diode uncontrolled rectifier circuit includes a first diode VD1, a second diode VD2, a third diode VD3, and a fourth diode VD4 that are bridged. A sixth capacitor C6 is connected in parallel with the output of the diode uncontrolled rectifier circuit. After output through the sixth capacitor C6, it is connected in parallel with the synchronous buck DC-DC converter module. The synchronous buck DC-DC converter includes a seventh NMOS transistor VT7, an eighth NMOS transistor VT8, a fifth inductor L5, and a seventh capacitor C7. The output side of the synchronous buck DC-DC converter is connected in parallel with an electrical load.

[0012] In a specific implementation, it further includes a microcontroller. Voltage / current signal acquisition components are provided in both the synchronous boost DC-DC converter module and the synchronous buck DC-DC converter module. The signals output by the voltage / current signal acquisition components are connected to the microcontroller. The output end of the microcontroller is connected to a control switch to control the duty cycle operating states of the first NMOS transistor VT1, the second NMOS transistor VT2, the seventh NMOS transistor VT7, and the eighth NMOS transistor VT8.

[0013] In specific implementation, the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 of the synchronous boost DC-DC converter component operate in the MPPT control mode based on Lyapunov backstepping control.

[0014] In specific implementation, the power electronic switching devices in the synchronous boost DC-DC converter component and the synchronous buck DC-DC converter component are replaced with fully controlled devices, and the fully controlled devices include NMOS or N-type IGBT fully controlled devices.

[0015] A photovoltaic power generation wireless energy transmission method uses the above-mentioned photovoltaic power generation wireless energy transmission system and includes the following steps:

[0016] (1) Photovoltaic module power generation: The photovoltaic module collects energy, and the energy is transmitted to the wireless energy transmission transmitting circuit, and is boosted through synchronous rectification technology to form direct current a.

[0017] (2) Wireless energy transmission: The direct current a is converted into alternating current b through a full-bridge inverter circuit, and the alternating current b forms alternating current c through an LCC-S resonant compensation mechanism.

[0018] (3) Wireless energy reception: After the alternating current c is converted into direct current d through a diode uncontrolled rectifier circuit, it is stepped down through synchronous rectification technology to form direct current e and then connected to an electrical load.

[0019] Among them, in the synchronous rectification technology, the Lyapunov maximum power point tracking mode or the constant voltage / constant current control mode is adopted; the mode selection is through the following steps: set the wireless energy power output threshold W E , the output power value W of the synchronous buck DC-DC converter component o , perform real-time comparison in the microcontroller. If W o >W E , control the first NMOS transistor VT1 and the second NMOS transistor VT2 of the synchronous boost DC-DC converter component to work in a fixed duty cycle, and the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter component work in the constant voltage / constant current mode. If W o <W E , control the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter component to work in a fixed duty cycle, and the first NMOS transistor VT1 and the second NMOS transistor VT2 in the synchronous boost DC-DC converter component work in the MPPT control mode based on Lyapunov backstepping control.

[0020] In specific implementation, in the Lyapunov maximum power point tracking mode, the duty cycle control formula is as follows:

[0021] D is the duty cycle of the DC-DC boost converter, u dc is the output voltage on both sides of the synchronous boost DC-DC converter module, u pv is the voltage across the first capacitor, i pv is the output current of the photovoltaic module, e1 and e2 are error coefficients, and the constants k1, k2 > 0.

[0022] In specific implementation, in the constant voltage / constant current control mode, when operating in the constant voltage mode, the expected voltage across the seventh capacitor C7 is subtracted from the actually measured voltage, and the expected current on the load side is calculated through a PI controller. Then, the actually measured current is subtracted from it, and the duty cycle of the synchronous DC-DC buck converter module is calculated through a PI controller. When operating in the constant current mode, the expected current on the load side is directly given, and then the actually measured current is subtracted from it, and the duty cycle of the synchronous buck DC-DC converter module is calculated through a PI controller, so as to limit the final charging voltage while realizing constant current charging.

[0023] In specific implementation, is the voltage across the first capacitor when the system is at maximum power, i L is the current flowing through the first inductor, i L * is the expected value of the current flowing through the first inductor. The expected value of the current flowing through the first inductor i L * = i pv + k1e1C1.

[0024] The beneficial effects of the present invention are as follows:

[0025] Compared with a diode, the on-resistance of a MOSFET is only dozens of mΩ. Therefore, in DC-DC conversion, the conduction loss of the freewheeling diode is greatly reduced, resulting in higher conversion efficiency. At the same time, by adopting multi-stage conversion of energy, the complexity of control is reduced to a certain extent. The LCC resonant topology exhibits the characteristics of a constant voltage source and has the characteristic of zero input reactive power, which can improve efficiency. The application of the MPPT control method of Lyapunov backstepping control makes the maximum power point tracking more stable. These technical features and combinations of technical features have not been mentioned in the prior art.

[0026] In the disclosed patented technology, the main research object is the receiving circuit, which has a simple structure. The control of the energy receiving circuit is mainly completed by hardware circuits such as a bandgap reference source and a signal generator. However, when modifying the control parameters, the hardware circuit needs to be modified, which is suitable for a general wireless energy receiving system.

[0027] In the present patent application, the main research object is the transmitting circuit and receiving circuit for connecting photovoltaic modules. In the scenarios adaptable to solar power generation, a microcontroller is mainly used to control the entire circuit. When modifying the control parameters, only the program needs to be modified, and the control method is flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a flowchart of a wireless power transmission system for photovoltaic power generation;

[0029] Figure 2 It is the photovoltaic side and the wireless power transmission transmitting circuit;

[0030] Figure 3 It is the wireless power transmission receiving circuit;

[0031] Figure 4 It is the maximum power point tracking control;

[0032] Figure 5 It is the constant voltage / constant current control;

[0033] Figure 6 It is the waveform diagram of power variation after adding light perturbation in the maximum power point tracking mode;

[0034] Figure 7 It is Example 1 of the waveform diagram of output voltage and current in the constant voltage / constant current control mode;

[0035] Figure 8 It is Example 2 of the waveform diagram of output voltage and current in the constant voltage / constant current control mode;

[0036] Figure 9 It is Example 3 of the waveform diagram of output voltage and current in the constant voltage / constant current control mode;

[0037] Figure 10 It is Example 4 of the waveform diagram of output voltage and current in the constant voltage / constant current control mode;

[0038] Figure 11 It is the schematic connection diagram of the microcontroller and the wireless power transmission system. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] The following describes the preferred embodiments of the present invention with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for explaining and illustrating the present invention, and are not used to limit the present invention.

[0040] Embodiment 1

[0041] A wireless power transmission system for photovoltaic power generation and a supporting transmission method, see Figures 1 to 10, along the energy transmission direction, it successively includes a photovoltaic side circuit, a wireless energy transmission transmitting circuit, and a wireless energy transmission receiving circuit; among them, the photovoltaic side circuit includes a photovoltaic module and a synchronous boost DC-DC converter module; the wireless energy transmission transmitting circuit includes a full-bridge inverter circuit module and the first half of an LCC-S resonant compensation mechanism; the wireless energy transmission receiving circuit includes the second half of the LCC-S resonant compensation module, a diode rectifier circuit module, a synchronous buck DC-DC converter module, and an electrical load; the synchronous boost DC-DC converter module includes a first capacitor C1. One side of the first capacitor C1 is connected to a first inductor L1, and the other side of the first capacitor C1 is connected in parallel to a first NMOS transistor VT1, a second NMOS transistor VT2. The other ends of the first NMOS transistor VT1 and the second NMOS transistor VT2 are connected to both ends of a second capacitor C2 to form the synchronous boost DC-DC converter module.

[0042] The full-bridge inverter circuit module includes a third NMOS transistor VT3, a fourth NMOS transistor VT4, a fifth NMOS transistor VT5, and a sixth NMOS transistor VT6 that are bridged.

[0043] The first half of the LCC-S resonant compensation module is the transmitting end. At the transmitting end, a second inductor L2 is in series with a third capacitor C3, and a fourth capacitor C4 is in series with a third inductor L3 and then in parallel with the third capacitor C3. The second half of the LCC-S resonant compensation module includes the output side of the LCC-S resonant compensation structure. The output side of the LCC-S resonant compensation structure includes a fourth inductor L4 and a fifth capacitor C5. The fourth inductor L4 is in series with the fifth capacitor C5. The fourth inductor L4 is installed corresponding to the third inductor L3. The output side of the LCC-S resonant compensation structure is in parallel with an uncontrolled diode rectifier circuit. The uncontrolled diode rectifier circuit includes a first diode VD1, a second diode VD2, a third diode VD3, and a fourth diode VD4 that are bridged. A sixth capacitor C6 is in parallel with the output of the uncontrolled diode rectifier circuit. After output through the sixth capacitor C6, it is in parallel with the synchronous buck DC-DC converter module. The synchronous buck DC-DC converter module includes a seventh NMOS transistor VT7, an eighth NMOS transistor VT8, a fifth inductor L5, and a seventh capacitor C7. The output side of the synchronous buck DC-DC converter module is in parallel with the electrical load.

[0044] It also includes a microcontroller. Voltage / current signal acquisition components are provided in both the synchronous boost DC-DC converter module and the buck DC-DC converter. The signals output by the voltage / current signal acquisition components are connected to the microcontroller. The output end of the microcontroller is connected to a control switch to control the duty cycle operating states of the first NMOS transistor VT1, the second NMOS transistor VT2, the seventh NMOS transistor VT7, and the eighth NMOS transistor VT8.

[0045] The seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 of the synchronous boost DC-DC converter module operate in the MPPT control mode based on Lyapunov backstepping control.

[0046] The power electronic switching devices of the synchronous boost DC-DC converter module and the synchronous buck DC-DC converter module are replaced with fully controlled devices, and the fully controlled devices include NMOS or N-type IGBT fully controlled devices.

[0047] A photovoltaic power generation wireless energy transmission method uses the above photovoltaic power generation wireless energy transmission system and includes the following steps:

[0048] (1) Photovoltaic module power generation: The photovoltaic module collects energy, and the energy is transmitted to the wireless energy transmission transmitting circuit, where boost conversion is achieved through synchronous rectification technology to form direct current a;

[0049] (2) Wireless energy transmission: The direct current a is converted into alternating current b through a full-bridge inverter circuit, and the alternating current b forms alternating current c through an LCC-S resonant compensation mechanism;

[0050] (3) Wireless energy reception: After the alternating current c is converted into direct current d through a diode uncontrolled rectifier circuit, step-down conversion is achieved through synchronous rectification technology to form direct current e, which is then connected to the electrical load;

[0051] Among them, in the synchronous rectification technology, the Lyapunov maximum power point tracking mode or the constant voltage / constant current control mode is adopted; the mode selection is carried out through the following steps: set the wireless energy power output threshold W E , the output power value W of the synchronous buck DC-DC converter module o , and perform real-time comparison in the microcontroller. If W o >W E , control the first NMOS transistor VT1 and the second NMOS transistor VT2 of the synchronous boost DC-DC converter module to work with a fixed duty cycle, and control the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter module to work in the constant voltage / constant current mode. If W o <W E , control the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter module to work with a fixed duty cycle, and control the first NMOS transistor VT1 and the second NMOS transistor VT2 of the synchronous boost DC-DC converter module to work in the MPPT control mode based on Lyapunov backstepping control.

[0052] In the Lyapunov maximum power point tracking mode, its duty cycle control formula is:

[0053] D is the duty cycle of the DC-DC boost converter, and u dc is the output voltage on both sides of the synchronous boost DC-DC converter module, and u pv is the voltage across the first capacitor, and i pv is the output current of the photovoltaic module, and e1, e2 are error coefficients, and the constants k1, k2 > 0.

[0054] In the constant voltage / constant current control mode, when operating in the constant voltage mode, the expected voltage across the seventh capacitor C7 is subtracted from the actually measured voltage, and the expected current on the load side is calculated through a PI controller. Then, the actually measured current is subtracted from it, and the duty cycle of the DC-DC buck converter is calculated through a PI controller. When operating in the constant current mode, the expected current on the load side is directly given, and then the actually measured current is subtracted from it, and the duty cycle of the synchronous buck DC-DC converter module is calculated through a PI controller, so as to limit the final charging voltage while realizing constant current charging.

[0055] is the voltage across the first capacitor when the system is at the maximum power, and i L is the current flowing through the first inductor, and i L * is the expected value of the current flowing through the first inductor, and the expected value of the current flowing through the first inductor i L * = i pv + k1e1C1.

[0056] Figure 6 is the power change curve when the environment of the photovoltaic module changes in the MPPT mode. It can be seen from the figure that this control method can quickly respond to the tracking of the maximum power point when the environment changes.

[0057] Figures 7 - 8 is the voltage-current change curve in the constant voltage mode. Let the given voltage The actual voltage reaches this steady-state value after 0.5 s.

[0058] Figures 9 - 10 is the voltage-current change curve in the constant current mode. Let the given current The actual current reaches this steady-state value in 2 s. During operation, a PI controller is usually used in the charger circuit. The purpose is to achieve constant-current charging while limiting the final charging voltage. The implementation method is to set two reference parameters, namely the desired voltage and the desired current in the text, which are used to control the current and voltage respectively. In the initial stage of charging, since the output voltage is low and does not reach the voltage limit value, only one control loop - the current loop - is in operation, and the output current is controlled, with the working mode being constant-current output. At the end of charging, the output voltage reaches the voltage limit value. At this time, the voltage loop starts to operate, the output voltage is limited, and the current loop loses its effect, with the working mode being constant-voltage output. Its control object is still the MOS transistor, and the control variables are the output voltage and current.

[0059] Set the charging power value W E , and the synchronous buck DC-DC converter component outputs the power value W o , and perform real-time comparison in the microcontroller. If W o >W E , control the first NMOS transistor VT1 and the second NMOS transistor VT2 of the DC-DC boost converter to work with a fixed duty cycle, and the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter component to work in a constant-voltage / constant-current mode. If W o <W E , control the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter component to work with a fixed duty cycle. During operation, the first NMOS transistor VT1 and the second NMOS transistor VT2 of the synchronous boost DC-DC converter component work in an MPPT control mode based on Lyapunov backstepping control.

[0060] During operation, due to environmental changes, the output power of the photovoltaic module is not fixed, and the load of the receiving part has a maximum power that it can withstand. During operation, this power cannot be exceeded. Therefore, the design of this application enables it to work in the MPPT control mode to maintain the maximum power at this time when the output power is insufficient, and directly control the current voltage magnitude when it exceeds this power. Controlling the current voltage magnitude also limits the output power.

[0061] In this application, a synchronous DC-DC converter component is adopted in the DC chopper circuit of the photovoltaic power generation wireless energy transmission system, an LCC resonance topology is adopted for the energy transmission part, and an MPPT control technology based on Lyapunov backstepping control is adopted on the photovoltaic side, which greatly improves the energy transmission efficiency.

[0062] Finally, it should be noted that the above are only preferred embodiments of the present invention and are not used to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements on some of the technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for wireless energy transmission of photovoltaic power generation, using a wireless energy transmission system for photovoltaic power generation, characterized in that, The photovoltaic power generation wireless energy transmission system sequentially includes a photovoltaic side circuit, a wireless energy transmission transmitting circuit, and a wireless energy transmission receiving circuit along the energy transmission direction; Among them, the photovoltaic side circuit includes a photovoltaic module and a synchronous boost DC-DC converter module; The wireless energy transmission transmitting circuit includes a full-bridge inverter circuit module and the first half of an LCC-S resonant compensation mechanism; The wireless energy transmission receiving circuit includes the second half of an LCC-S resonant compensation module, a diode rectifier circuit module, a synchronous buck DC-DC converter module, and an electrical load; The synchronous boost DC-DC converter module includes a first capacitor C1. One side of the first capacitor C1 is connected to one end of a first inductor L1. The other end of the first inductor L1 is connected to one ends of a first NMOS transistor VT1 and a second NMOS transistor VT2. The other side of the first capacitor C1 is connected in parallel with the second NMOS transistor VT2. The other ends of the first NMOS transistor VT1 and the second NMOS transistor VT2 are connected to both ends of a second capacitor C2 to form a synchronous boost DC-DC converter module. The synchronous buck DC-DC converter module includes a seventh NMOS transistor VT7, an eighth NMOS transistor VT8, a fifth inductor L5, and a seventh capacitor C7. The output side of the synchronous buck DC-DC converter module is connected in parallel with an electrical load; The photovoltaic power generation wireless energy transmission method includes the following steps: (1) Photovoltaic module power generation: The photovoltaic module collects energy, and the energy is transmitted to the wireless energy transmission transmitting circuit, and boost is achieved through synchronous rectification technology to form direct current a; (2) Wireless energy transmission: The direct current a is converted into alternating current b through a full-bridge inverter circuit, and the alternating current b forms alternating current c through an LCC-S resonant compensation mechanism; (3) Wireless energy reception: After the alternating current c is converted into direct current d through a diode uncontrolled rectifier circuit, buck is achieved through synchronous rectification technology to form direct current e, which is then connected to an electrical load; Among them, in the synchronous rectification technology, the Lyapunov maximum power point tracking mode or the constant voltage / constant current control mode is adopted; the mode is selected through the following steps, and the wireless energy power output threshold W is set E , the output power value W of the synchronous buck DC-DC converter component o , perform real-time comparison in the microcontroller. If W o > W E , control the first NMOS transistor VT1 and the second NMOS transistor VT2 of the synchronous boost DC-DC converter component to work in a fixed duty cycle, and the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter component work in a constant voltage / constant current mode. If W o < W E , control the seventh NMOS transistor VT7 and the eighth NMOS transistor VT8 in the synchronous buck DC-DC converter component to work in a fixed duty cycle, and the first NMOS transistor VT1 and the second NMOS transistor VT2 in the synchronous boost DC-DC converter component work in the MPPT control mode based on Lyapunov backstepping control.

2. The photovoltaic power generation wireless energy transmission method according to claim 1, characterized in that: The full-bridge inverter circuit module includes a third NMOS transistor VT3, a fourth NMOS transistor VT4, a fifth NMOS transistor VT5, and a sixth NMOS transistor VT6 that are bridged.

3. The photovoltaic power generation wireless energy transmission method according to claim 1, characterized in that: The first half of the LCC-S resonant compensation component is the transmitting end. At the transmitting end, the second inductor L2 is connected in series with the third capacitor C3, and the fourth capacitor C4 is connected in series with the third inductor L3 and then connected in parallel with the third capacitor C3. The second half of the LCC-S resonant compensation component includes the output side of the LCC-S resonant compensation structure. The output side of the LCC-S resonant compensation structure includes the fourth inductor L4 and the fifth capacitor C5. The fourth inductor L4 is connected in series with the fifth capacitor C5, and the fourth inductor L4 is installed corresponding to the third inductor L3. The output side of the LCC-S resonant compensation structure is connected in parallel with the diode uncontrolled rectifier circuit. The diode uncontrolled rectifier circuit includes the first diode VD1, the second diode VD2, the third diode VD3, and the fourth diode VD4 connected in a bridge. The sixth capacitor C6 is connected in parallel with the output of the diode uncontrolled rectifier circuit. After being output through the sixth capacitor C6, it is connected in parallel with the synchronous buck DC-DC converter component. The synchronous buck DC-DC converter component includes the seventh NMOS transistor VT7, the eighth NMOS transistor VT8, the fifth inductor L5, and the seventh capacitor C7. The output side of the synchronous buck DC-DC converter component is connected in parallel with the electrical load.

4. The photovoltaic power generation wireless energy transmission method according to claim 3, wherein: It further includes a microcontroller. Voltage / current signal acquisition elements are provided in both the synchronous boost DC-DC converter component and the synchronous buck DC-DC converter component. The signals output by the voltage / current signal acquisition elements are connected to the microcontroller. The output end of the microcontroller is connected to a control switch to control the duty cycle operating states of the first NMOS transistor VT1, the second NMOS transistor VT2, the seventh NMOS transistor VT7, and the eighth NMOS transistor VT8.

5. The photovoltaic power generation wireless energy transmission method according to claim 4, wherein: Among them, the first NMOS transistor VT1 and the second NMOS transistor VT2 in the synchronous boost DC-DC converter component operate in the MPPT control mode based on Lyapunov backstepping control.

6. The photovoltaic power generation wireless energy transmission method according to claim 1, wherein: In the Lyapunov maximum power point tracking mode, its duty cycle control formula is: D is the duty cycle of the DC-DC boost converter, and u dc is the output voltage on both sides of the synchronous DC-DC boost converter component, and u pv is the voltage across the first capacitor, and i pv is the output current of the photovoltaic module, is the error coefficient, and the constants k1, k2 > 0; is the voltage across the first capacitor when the system is at the maximum power, and i L is the current flowing through the first inductor, and i L * is the expected value of the current flowing through the first inductor, and the expected value of the current flowing through the first inductor i L * = i pv + k1e1C1.

7. The photovoltaic power generation wireless energy transmission method according to claim 1, characterized in that: In the constant voltage / constant current control mode, when operating in the constant voltage mode, the expected voltage across the seventh capacitor C7 is subtracted from the actually measured voltage, and the expected current on the load side is calculated through a PI controller. Then, it is subtracted from the actually measured current, and the duty cycle of the DC-DC buck converter is calculated through a PI controller. When operating in the constant current mode, the expected current on the load side is directly given, and then it is subtracted from the actually measured current, and the duty cycle of the synchronous buck DC-DC converter component is calculated through a PI controller, so as to achieve constant current charging while limiting the final charging voltage.

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