CN116014917A - Wireless energy supply system and its closed-loop control method, maximum power tracking method - Google Patents

Abstract

The invention provides a wireless energy supply system, a closed-loop control method thereof, and a maximum power tracking method, belonging to the technical field of wireless energy transmission. The above-mentioned wireless energy supply system includes: a photovoltaic array, a DC-DC converter and an energy storage battery; the above-mentioned closed-loop control method includes: monitoring the output voltage of the photovoltaic array in real time, according to the real-time output voltage of the DC-DC converter, the real-time output current and The state conditions satisfied by the real-time state of charge of the energy storage battery determine the working modes of the wireless energy supply system, and these working modes include maximum power tracking mode, constant current output mode and constant voltage output mode. The invention supports adaptively switching the working mode of the system, so that the wireless energy supply system can meet the maximum output power while avoiding the overload phenomenon of the energy storage battery, ensuring the safe and stable operation of the whole system, improving the energy utilization efficiency of the photovoltaic array, and at the same time The service life of the energy storage battery is improved.

Description

Wireless energy supply system and its closed-loop control method, maximum power tracking method

technical field

The invention relates to the technical field of wireless energy transmission, in particular to a wireless energy supply system, a closed-loop control method thereof, and a maximum power tracking method.

Background technique

Laser wireless energy supply technology uses laser as the energy carrier to realize wireless energy transmission, converts the electric energy of the power system into laser energy, and then accurately transmits the laser energy to the photovoltaic array, and the photovoltaic array converts the laser energy into electrical energy for storage. Engines provide energy or perform other tasks. Due to the strong directionality and energy concentration of the laser, it can carry a large amount of energy. As a long-distance transmission method, it has higher photoelectric conversion efficiency and higher output power than solar cells. It can provide 24-hour uninterrupted power for the energy supply object and is widely used. In the energy supply of aerostats that cannot be directly supplied with electricity from the ground through transmission cables.

In the actual application of the current laser wireless energy supply system, it is restricted by the principle of laser emission, and the laser intensity is unevenly distributed in the cross section, resulting in different laser light intensity received by each single photovoltaic cell in the photovoltaic array composed of series and parallel. , which in turn leads to the current mismatch between the individual cells, and finally makes the P-U (output power-output voltage) characteristic curve of the photovoltaic array output present multi-peaks, and it changes dynamically in real time with the light intensity and the temperature of the photovoltaic cell itself. At present, DC-DC converters and maximum power tracking control algorithms are commonly used to achieve the maximum power output of photovoltaic arrays in laser wireless energy supply systems.

However, the existing maximum power tracking control algorithm is prone to fall into local optimum, which leads to difficulties in maximum power tracking and the realization of the maximum output capability of photovoltaic arrays. In addition, due to the influence of light intensity, photovoltaic cell temperature changes and load changes, the output of the laser wireless energy supply system is difficult to maintain stability, and the traditional linear closed-loop control method is difficult to ensure the robustness and dynamic performance of the system under large signal disturbances. It can be seen that the existing laser wireless energy supply system is still difficult to guarantee a stable and optimal power output capability.

Contents of the invention

Aiming at the problems existing in the prior art, embodiments of the present invention provide a wireless energy supply system, a closed-loop control method thereof, and a maximum power tracking method.

The present invention provides a wireless energy supply system, including: a photovoltaic array, a DC-DC converter, and an energy storage battery; the photovoltaic array is connected to the energy storage battery through the DC-DC converter; the DC-DC The converter contains a main control chip; where,

The main control chip is used to monitor the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery;

The main control chip is also used to determine the state conditions of the wireless energy supply system according to the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery. Operating mode.

According to a wireless energy supply system provided by the present invention, the main control chip includes a maximum power tracking mode control loop; the working mode includes a maximum power tracking mode;

The maximum power tracking mode control loop is further used when the real-time state of charge of the energy storage battery is not in a fully charged state, and the real-time output current of the DC-DC converter is not higher than that of the energy storage battery When the charging current is safe, it is determined that the working mode of the wireless energy supply system is the maximum power tracking mode;

The maximum power tracking mode includes: adjusting the duty ratio of the DC-DC converter to change the output power of the photovoltaic array until the output power of the photovoltaic array reaches the maximum power in the current state.

According to a wireless energy supply system provided by the present invention, the main control chip includes a constant voltage output mode control loop; the working mode includes a constant voltage output mode;

The constant voltage output mode control loop is used to switch the working mode to the constant voltage output mode when the real-time state of charge of the energy storage battery is in a fully charged state;

The constant voltage output mode includes: adjusting the output voltage of the DC-DC converter, so that the output voltage of the DC-DC converter is the same as the full-charge voltage of the energy storage battery.

According to a wireless energy supply system provided by the present invention, the main control chip includes a constant current output mode control loop, and the working mode includes a constant current output mode;

The constant current output mode control loop is used to ensure that the real-time state of charge of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter is higher than the safe charge of the energy storage battery current, switch the working mode of the wireless energy supply system to the constant current output mode; the constant current output mode includes: adjusting the duty cycle of the DC-DC converter so that the DC-DC The output current of the converter is the same as the safe charging current of the energy storage battery.

According to a wireless energy supply system provided by the present invention, the system further includes a laser emitting end; wherein,

The laser emitting end is used to emit laser light to the photovoltaic array, so that the photovoltaic array converts laser energy into a first voltage, and outputs the first voltage to the DC-DC converter;

The DC-DC converter is used to convert the first voltage into a second voltage for the energy storage battery to store electric energy.

The present invention also provides a closed-loop control method, which is applied to the wireless energy supply system described in any one of the above; including:

monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery;

The working mode of the wireless energy supply system is determined according to the state conditions satisfied by the real-time output voltage and real-time output current of the DC-DC converter and the real-time charge state of the energy storage battery.

According to a closed-loop control method provided by the present invention, according to the state conditions satisfied by the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery, the wireless The working mode of the energy supply system, including:

When the real-time state of charge of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, then determine that the wireless energy supply The working mode of the system is the maximum power tracking mode; the maximum power tracking mode includes: adjusting the duty cycle of the DC-DC converter so that the output power of the photovoltaic array changes until the output power of the photovoltaic array Reach the maximum output power in the current state.

According to a closed-loop control method provided by the present invention, according to the state conditions satisfied by the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery, the wireless The working mode of the energy supply system, including:

When the real-time state of charge of the energy storage battery is in a fully charged state, the working mode of the wireless energy supply system is switched to a constant voltage output mode; the constant voltage output mode includes: adjusting the DC-DC conversion The duty ratio of the converter is adjusted so that the output voltage of the DC-DC converter is the same as the fully charged voltage of the energy storage battery.

According to a maximum power tracking method provided by the present invention, the state conditions satisfied by the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery are determined to determine the The working mode of the wireless energy supply system, including:

When the real-time state of charge of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter is higher than the safe charging current of the energy storage battery, the wireless energy supply system The working mode of the DC-DC converter is switched to the constant current output mode; the constant current output mode includes: adjusting the duty cycle of the DC-DC converter, so that the output current of the DC-DC converter is the same as the safe charging current of the energy storage battery .

The present invention also provides a maximum power tracking method, which is applied to the above wireless energy supply system, including:

monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery;

When the real-time state of charge of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, then determine that the wireless energy supply The working mode of the system is the maximum power tracking mode; the maximum power tracking mode includes: adjusting the duty cycle of the DC-DC converter so that the output power of the photovoltaic array changes until the output power of the photovoltaic array Reach the maximum output power under the current ambient state.

According to a maximum power tracking method provided by the present invention, the maximum power tracking mode further includes:

Taking the duty cycle of the DC-DC converter as the position variable of the particle in the particle swarm, using the particle swarm optimization algorithm based on the predator search strategy to iteratively update the position variable of the particle to obtain the global optimum of the particle swarm Location;

The output voltage of the photovoltaic array and the maximum output power of the wireless energy supply system corresponding to the output voltage under the current environmental state are obtained through calculation based on the global optimal position.

According to a maximum power tracking method provided by the present invention, the maximum power tracking mode further includes:

determining the global search space of the duty cycle of the DC-DC converter, and dividing the global search space into a plurality of subspaces of different levels;

determine the subspace of the current level to be searched;

Initialize the size of the particle swarm and the maximum number of iterations in the subspace of the current level;

Perform iterative optimization in the subspace of the current level, and update the local optimal solution according to the preset fitness function until a better solution is obtained within the preset maximum number of iterations;

Taking the better solution as the historical optimal solution, and updating the level according to the level relationship to obtain the updated subspace of the current level; return to the step of determining the subspace of the current level to be searched.

According to the maximum power tracking method provided by the present invention, it also includes: if there is no better solution within the preset maximum number of iterations, updating the level according to the level relationship, obtaining the updated subspace of the current level, and returning to the determination The subspace of the current level to be searched until the updated level reaches the preset level, and the currently obtained historical optimal solution is output;

The currently obtained historical optimal solution is taken as the global optimal solution in the global search space.

According to the maximum power tracking method provided by the present invention, after monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery, it further includes:

After performing a weighted comparison of the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery using a preset weight function, judge the power of the photovoltaic array wireless energy supply system according to the comparison result. Status condition met.

The present invention also provides an electronic device, including a memory, a processor, and a computer program stored on the memory and operable on the processor. When the processor executes the program, any one of the above closed-loop control methods is implemented, or Any one of the maximum power tracking methods.

The present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, any one of the above-mentioned closed-loop control methods, or any one of the above-mentioned maximum power tracking methods .

The present invention also provides a computer program product, including a computer program. When the computer program is executed by a processor, any one of the above closed-loop control methods, or any one of the above maximum power tracking methods is implemented.

The wireless energy supply system and the maximum power tracking method provided by the present invention monitor the output voltage of the photovoltaic array in real time, according to the state satisfied by the real-time output voltage, real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery Conditions, determine the working mode of the wireless energy supply system, so that the working mode of the wireless energy supply system can be switched flexibly, so that the photovoltaic array works near the maximum output power point, while ensuring the safe operation of the energy storage battery, and improving the energy of the photovoltaic array. Utilization efficiency, while improving the service life of the energy storage battery.

Description of drawings

In order to more clearly illustrate the present invention or the technical solutions in the prior art, the accompanying drawings that need to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings in the following description are the present invention. For some embodiments of the invention, those skilled in the art can also obtain other drawings based on these drawings without creative effort.

Fig. 1 is a schematic structural diagram of a wireless energy supply system provided by the present invention;

Fig. 2 is a schematic flow chart of the closed-loop control method provided by the present invention;

Figure 3(a) is a schematic diagram of the I-V curve of a photovoltaic cell;

Figure 3(b) is a schematic diagram of the P-U curve of the photovoltaic cell;

Fig. 4 is one of the schematic flow charts of the maximum power tracking method provided by the present invention;

Fig. 5 is the second schematic flow diagram of the maximum power tracking method provided by the present invention;

Fig. 6 is a schematic diagram of a global search space and its subspaces;

Fig. 7 is the third schematic flow chart of the maximum power tracking method provided by the present invention;

Fig. 8 is a schematic structural diagram of a linear weighted compensator in the wireless energy supply system provided by the present invention;

Fig. 9 is a schematic structural diagram of a photovoltaic array in a wireless energy supply system in an embodiment;

Fig. 10 is a schematic diagram of a circuit structure of a wireless energy supply system in an embodiment;

Fig. 11 is a schematic diagram of the running results of the maximum power tracking method provided by the present invention;

Fig. 12(a) is a schematic diagram of the power change of the running result of the maximum power tracking method provided by the present invention;

Figure 12(b) is a schematic diagram of the current change in the schematic diagram of the operating results of the maximum power tracking method provided by the present invention;

Figure 12(c) is a schematic diagram of the voltage change in the schematic diagram of the operating results of the maximum power tracking method provided by the present invention;

Fig. 13 is a schematic structural diagram of an electronic device provided by the present invention.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Obviously, the described embodiments are part of the embodiments of the present invention , but not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

The specific implementation manner of the present invention will be described below with reference to FIGS. 1-13 .

As shown in Figure 1, Figure 1 shows a schematic diagram of a wireless energy supply system in the present invention; the wireless energy supply system includes a photovoltaic array, a DC-DC converter (Direct Current-Direct Current Converter; DC-DC converter) and storage The photovoltaic array is connected to the energy storage battery through a DC-DC converter. Tracking of maximum output power of photovoltaic arrays. The DC-DC converter contains a main control chip. The circuit structure of the main control chip mainly includes the maximum power tracking mode control loop, the constant voltage output mode control loop, the constant current output mode control loop, the control mode decision module and the PWM (Pulse Width Modulation, PWM, pulse width modulation) module; each control loop can monitor the input and output signals of the DC-DC converter, and use their respective comparison links to calculate the difference e between the output voltage of the photovoltaic array and the reference voltage, and then pass Respective adaptive closed-loop controllers are used to realize the switching of the wireless energy supply system in different working modes, or when a disturbance occurs, the duty cycle of the DC-DC converter is adjusted through the PWM module to achieve the maximum output of the photovoltaic array Power tracking and stability control of the system.

In one embodiment, the above-mentioned main control chip is used to monitor the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery.

Among them, the DC-DC converter, that is, the DC converter, is used to convert the DC voltage output by the photovoltaic array into a DC voltage that can be used by the energy storage battery or the load; its main working mode is pulse width modulation (Pulse Width Modulation, PWM, Pulse Width Modulation) working method, the basic principle is to cut the direct current into a square wave (pulse wave) through the switch tube, and adjust the duty cycle of the square wave (the ratio of the pulse width to the pulse period) through the PWM module to change the voltage. Optionally, the DC-DC converter may be a buck converter or a boost converter. Energy storage battery, also known as storage battery, its real-time state of charge (State of Charge, SOC) is used to reflect the ratio of the remaining capacity of the battery to the full capacity of the battery.

Specifically, the main control chip samples the input and output signals of the DC-DC converter to obtain the real-time output voltage of the DC-DC converter , real-time output current , the main control chip can also obtain the real-time state of charge SOC of the energy storage battery through sampling.

The above-mentioned main control chip is also used to determine the working mode of the wireless energy supply system according to the state conditions satisfied by the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery.

Specifically, in order to realize that the photovoltaic array always works near the maximum output power point, it is necessary to judge whether the current wireless energy supply system is working at the maximum output power point of the photovoltaic array through the real-time output voltage and real-time output current of the DC-DC converter. Near the output power point, if the photovoltaic array does not work near the maximum output power point, the duty cycle of the DC-DC converter is adjusted through the maximum power tracking mode control loop until the output power of the photovoltaic array reaches the maximum output under the current environmental conditions power point.

In addition, since the wireless energy supply system includes a photovoltaic array and an energy storage battery, the working state of the energy storage battery is also susceptible to changes in the environment (such as its own temperature), and the output voltage or output current of the photovoltaic array may exceed the safety of the energy storage battery. The operating current or full voltage may cause system instability, so the present invention can also judge the current Whether the wireless energy supply system is working in an unsafe state, so as to adjust the real-time output voltage and real-time output current of the DC-DC converter to ensure the safe and stable operation of the wireless energy supply system; specifically, the main control chip can pass constant voltage The output mode control loop or the constant current output mode control loop collects the real-time output voltage, real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery, and judges the difference between the above-mentioned real-time sampling value and the reference value through their respective comparison links. The difference between them, so as to judge the current working mode of the wireless energy supply system, and switch the wireless energy supply system to the constant voltage output mode or constant current output mode by triggering the control mode decision module.

In the above embodiments, the physical quantities in the wireless energy supply system are monitored in real time by the main control chip in the DC-DC converter, the state conditions satisfied by the wireless energy supply system are judged through the relationship between each physical quantity, and the wireless energy supply system is adaptively adjusted according to the state conditions. The working mode of the energy supply system enables the wireless energy supply system to meet the maximum power output while ensuring the safe and stable operation of the wireless energy supply system, ensuring the efficient conversion and utilization of energy in the entire wireless energy supply system, and improving the stability and stability of the entire system. reliability.

In an embodiment, the above-mentioned main control chip includes a maximum power tracking mode control loop; the above-mentioned working mode includes a maximum power tracking mode.

The above maximum power tracking mode control loop is further used to determine when the real-time state of charge of the energy storage battery is not in a fully charged state, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery The working mode of the wireless energy supply system is the maximum power tracking mode; the maximum power tracking mode includes: adjusting the duty cycle of the DC-DC converter to change the equivalent load of the photovoltaic array until the output power of the photovoltaic array reaches the current state of the maximum power.

Specifically, as shown in Figure 1, the above-mentioned maximum power tracking mode control loop includes the input voltage for the DC-DC converter ,Input Current The sampling link, MPPT controller (maximum power tracking controller), comparison link, adaptive closed-loop controller . where the input voltage ,Input Current It is the input voltage and input current of the DC-DC converter, that is, the output voltage and output current of the photovoltaic array; the MPPT controller is used to set the reference voltage of the maximum power point , the comparison link calculates the output voltage of the photovoltaic array by comparison reference voltage with maximum power point The difference e between, and then through the adaptive closed-loop controller According to the judgment result of the difference e, the trigger control mode decision-making module switches the working mode of the wireless energy supply system to the maximum power tracking mode. In the maximum power tracking mode, the duty cycle of the DC-DC converter is adjusted by the PWM module , to realize the maximum output power tracking of the photovoltaic array.

Further, the global maximum power tracking of the output multi-peak power curve of the photovoltaic array can be realized through the MPPT (Maximum Power Point Tracking) algorithm.

Furthermore, the above MPPT algorithm can be implemented by using the Predatory Search-Particle Swarm Optimization (PS-PSO) algorithm based on the predatory search strategy.

In the above embodiments, by monitoring the output voltage of the photovoltaic array in real time, the output voltage of the photovoltaic array can be adjusted so that the photovoltaic array works near the maximum output power point, and the energy utilization efficiency of the photovoltaic array can be improved.

In one embodiment, as shown in FIG. 1 , the above-mentioned main control chip includes a constant voltage output mode control loop; the above-mentioned working mode includes a constant voltage output mode.

The above constant voltage output mode control loop is used to switch the working mode of the wireless energy supply system to the constant voltage output mode through the control mode decision module when the real-time state of charge of the energy storage battery is in a fully charged state; the above constant voltage output mode The mode includes: adjusting the output voltage of the DC-DC converter so that the output voltage of the DC-DC converter is the same as the voltage of the energy storage battery.

Specifically, an excessively high output voltage of the photovoltaic array will affect the life of the energy storage battery. In order to ensure that the energy storage battery works in a safe working mode, the present invention also uses a constant voltage output mode control loop. The constant voltage output mode control loop consists of the output voltage of the DC-DC converter The sampling link, the voltage comparison link, and the adaptive closed-loop controller . The output voltage of the DC-DC converter obtained by sampling with a preset reference output voltage Compare to get the difference e, adaptive closed-loop controller Judge e, and according to the judgment result, switch the wireless energy supply system to the constant voltage output mode through the control mode decision module, and adjust the duty cycle of the DC-DC converter through PWM to adjust the output of the DC-DC converter Voltage , to limit the output voltage of the DC-DC converter , making it the same as the fully charged voltage of the energy storage battery.

In the above embodiment, the output voltage of the DC-DC converter is controlled by using the constant voltage output mode control loop, so that when the energy storage battery is fully charged, the output voltage of the DC-DC converter is the same as the voltage of the energy storage battery , can ensure that the energy storage battery works in a safe working mode, and improve the service life of the energy storage battery.

In one embodiment, the above-mentioned main control chip includes a constant current output mode control loop, and the above-mentioned working mode includes a constant current output mode.

The above constant current output mode control loop is used to wirelessly supply energy when the real-time state of charge of the energy storage battery is not fully charged and the real-time output current of the DC-DC converter is higher than the safe charging current of the energy storage battery. The working mode of the system is switched to the constant current output mode; the constant current mode includes: adjusting the duty cycle of the DC-DC converter so that the output current of the DC-DC converter is the same as the safe charging current of the energy storage battery.

Specifically, as shown in Figure 1, the constant current output mode control loop includes the output current Sampling link, current comparison link, adaptive closed-loop controller . where the output current is the output current of the DC-DC converter, and the current comparison link is used to compare the above output current The size between the safe charging current of the energy storage battery, when the output current of the DC-DC converter When the charging current is greater than the safe charging current of the energy storage battery, the adaptive closed-loop controller Based on the judgment of the comparison result e, the trigger control mode decision module switches the working mode of the wireless energy supply system to the constant current output mode. In the constant current output mode, the duty cycle of the DC-DC converter is adjusted by the PWM module to make the output current It is the same as the safe charging current of the energy storage battery.

In the above embodiment, by monitoring the real-time output current of the DC-DC converter and comparing the real-time output voltage with the safe charging current of the energy storage battery, switching the working mode of the wireless energy supply system to the constant current output mode can ensure The output power of the array tends to be maximized while ensuring the safe and reliable operation of the wireless energy supply system and improving the service life of the energy storage battery.

In one embodiment, the above wireless energy supply system further includes a laser emitting end, the above laser emitting end is used to emit laser light to the photovoltaic array, so that the photovoltaic array uses the laser energy to output the first voltage to the DC-DC converter; DC- The DC converter is used to transform the first voltage into a second voltage for the energy storage battery to store electric energy.

Specifically, the wireless energy supply system provided by the present invention can be applied to the conversion and utilization of sunlight, laser or other light energy. This embodiment especially provides a wireless energy supply system applied to laser energy transmission and conversion, as shown in the figure 1, the wireless energy supply system also includes a laser emitting end, wherein the laser emitting end is used to emit laser light to the photovoltaic array, so that the photovoltaic array converts the laser energy into a first voltage, and outputs the first voltage to DC- DC converter; DC-DC converter, used to convert the first voltage to the second voltage, so as to store electric energy for the energy storage battery or use electric energy for the load. The main control chip of the DC-DC converter controls the working mode of the entire system, which will not be repeated here.

The above embodiments provide a wireless energy supply system applied to laser energy transmission, through which the wireless energy supply system can solve the problem that the output power of the photovoltaic array is difficult to maintain near the maximum power operating point due to the instability of laser light emission, and at the same time The system can also ensure the safe and stable operation of the laser energy wireless energy supply system and improve the service life of the energy storage battery.

In one embodiment, as shown in Figure 2, a closed-loop control method is provided, and the application of the method to the wireless energy supply system in Figure 1 is used as an example for illustration. The DC-DC converter in the wireless energy supply system includes Main control chip, the main control chip is used to perform the following steps:

Step 201, monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery.

Among them, the DC-DC converter, that is, the DC conversion circuit, is used to convert the DC voltage output by the photovoltaic array into a DC voltage that can be used by the energy storage battery or the load; its main working mode is pulse width modulation (Pulse Width Modulation, PWM, pulse Width modulation) working mode, the basic principle is to chop the direct current into a square wave (pulse wave) through the switch tube, and change the voltage by adjusting the duty cycle of the square wave (the ratio of the pulse width to the pulse period). Optionally, the DC-DC converter may be a buck converter or a boost converter. The energy storage battery, also known as the storage battery, is used to store the current output by the photovoltaic array, and the real-time state of charge of the energy storage battery is used to reflect the ratio of the remaining capacity of the battery to the full capacity of the battery.

Specifically, the main control chip samples the input and output signals of the DC-DC converter, as shown in Figure 1, to obtain the real-time output voltage of the DC-DC converter , real-time output current , the main control chip can also obtain the real-time state of charge (State of Charge, SOC) of the energy storage battery through sampling.

Step 202, judging the above-mentioned real-time output voltage , real-time output current 1. The state conditions satisfied by the real-time state of charge SOC, and switch the working mode of the wireless energy supply system according to the state conditions. Specifically include: as shown in Figure 1, when the real-time state of charge SOC of the energy storage battery and the real-time output current of the DC-DC converter When the first state condition is met, it is determined that the operating mode of the system is the maximum power tracking mode; the maximum power tracking mode includes: adjusting the duty cycle of the DC-DC converter through the PWM module, so that the equivalent load of the photovoltaic array changes until The output power of the photovoltaic array reaches the maximum power in the current state.

Among them, the maximum power tracking mode, generally called MPPT (Maximum Power Point Tracking, maximum power point tracking), refers to adjusting the output power of the photovoltaic array according to different ambient temperatures, light intensity, and the operating characteristics of the photovoltaic array itself. , so that the photovoltaic array always outputs the maximum power. The principle of the maximum output power tracking method of the photovoltaic array is shown in Figure 3(a) and Figure 3(b). Figure 3(a) shows the output voltage-output current curve (IV curve) of the photovoltaic cell, and Figure 3 (b) shows the output power-output voltage curve (PU curve) of photovoltaic cells, in Figure 3(a) and Figure 3(b), is the equivalent load of the photovoltaic cell, is the equivalent output voltage of the photovoltaic cell; P is the output power of the photovoltaic cell; D is the duty cycle of the DC-DC converter, and the duty cycle D refers to the pulse width and pulse period of the pulse signal output by the DC-DC converter In the present invention, the duty cycle of the DC-DC converter can be calculated according to the sampling value of the real-time output voltage of the DC-DC converter; in Figure 3(a), point O is the maximum The output power point, taking ray A as the dividing line, the operating characteristic curve above the ray A is relatively flat, it can be seen that the photovoltaic cell is basically a constant current output, and the operating characteristic curve below the ray A shows that the output voltage of the photovoltaic cell is basically unchanged. It is a constant voltage output; it can be clearly seen from Figure 3 (b) that the operating characteristics of photovoltaic cells are nonlinear. Under a certain ambient temperature and light intensity, as the output voltage increases, the output power first increases and then increases. If it becomes smaller, a maximum power point will appear in the PU curve. The working principle of MPPT is to make full use of the working characteristics of photovoltaic cells to make them operate at the maximum output power point. By adjusting the equivalent load of photovoltaic cells, the output voltage of photovoltaic cells can be changed. and output current up to the maximum output power. The maximum output power point is also affected by environmental conditions such as temperature and light intensity. For example, the maximum output power of a photovoltaic array in the morning is 500W, but in the afternoon, its maximum output power may become 800W, so how to find the current value of the photovoltaic cell? It is necessary to track the maximum power point in the state and to keep the photovoltaic cells working efficiently; in addition, the photovoltaic array is vulnerable to the surrounding environment (such as floating clouds, buildings, tree shade, etc.) The interference of dust causes the output power of the photovoltaic array to decrease, and the output characteristic curve becomes complicated. For example, the output characteristic curve presents multiple extreme points (multiple peaks). At this time, it is more necessary to use MPPT to find the maximum power point of the photovoltaic cell.

Specifically, in order to maintain the maximum power output of the photovoltaic array and at the same time make the entire wireless energy supply system run safely and stably, the present invention uses a control mode decision-making module to determine or switch the working mode of the entire system according to the real-time state parameters collected above; the control mode The decision-making module realizes the on-off of the corresponding switch circuit according to the above real-time state parameters. When the real-time state parameters meet the corresponding state conditions, it will use the maximum power tracking mode control loop, constant voltage output mode control loop or constant current output as shown in Figure 1. mode control loop to regulate the output voltage or output current of the photovoltaic array.

In the above embodiment, the real-time state parameters in the wireless energy supply system are monitored in real time through the main control chip in the DC-DC converter, the state conditions satisfied by the wireless energy supply system are judged through the relationship between each real-time state parameter, and the state conditions are automatically determined according to the state conditions. Adaptively adjust the working mode of the wireless energy supply system, so that the wireless energy supply system can meet the maximum power output while ensuring the safe and stable operation of the wireless energy supply system, ensuring the efficient conversion and utilization of energy in the entire wireless energy supply system, and can Ensure the dynamic performance and stability of the wireless energy supply system when the energy supply system is disturbed or when the working mode is switched.

As shown in Figure 4, Figure 4 shows the overall flow diagram of the above maximum power tracking method; after sampling the real-time output voltage, real-time output current of the DC-DC converter and the real-time state of charge SOC of the energy storage battery, the After the obtained signal is subjected to signal conditioning amplification and A/D conversion (AC/DC conversion), the working mode required by the current system is judged by comparing the size relationship of each parameter. First, judge whether voltage and current protection is needed. If not, run Maximum power tracking algorithm, so that the photovoltaic array operates at the maximum output power operating point in real-time state.

In an embodiment, the above step 202 includes: when the real-time state of charge SOC of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, then It is determined that the above wireless energy supply system does not require output voltage protection or output current protection, and the current required working mode is the maximum power tracking mode. The maximum power tracking mode includes: as shown in Figure 4, adjusting the DC-DC converter through the PWM module The duty cycle D of the photovoltaic array is used to change the equivalent load of the photovoltaic array, that is, the output power of the photovoltaic array, until the output power of the photovoltaic array reaches the maximum power under the current environmental state and maintains the maximum power output. If it is detected that the light intensity received by the photovoltaic array changes, or the temperature of the photovoltaic array changes, it means that the maximum power point of the photovoltaic array has changed. Continue to find the maximum power point suitable for the current light intensity or temperature, and set The output power of the PV array is adjusted to the latest maximum power point.

Further, when the light intensity or temperature is constant, if the load changes, the duty ratio D of the DC-DC converter is adjusted through the PWM module to change the equivalent load of the photovoltaic array, that is, the output of the photovoltaic array The power is varied to energize the load. If the load does not change, maintain the current maximum power output.

In the above embodiment, when it is judged that the energy storage battery is not fully charged and the output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, the duty cycle is adjusted so that the photovoltaic battery always works in a real-time environment In the vicinity of the maximum power point in the state, the maximum power output capability of the photovoltaic system can be guaranteed, and the energy use efficiency of the photovoltaic system can be maximized.

In an embodiment, the above step 202 further includes: when the real-time state of charge of the energy storage battery is fully charged, then switching the working mode of the wireless energy supply system to the constant voltage output mode; the constant voltage output mode includes: The duty ratio of the DC-DC converter is adjusted so that the output voltage of the DC-DC converter is the same as the full voltage of the energy storage battery.

Since the working state of the energy storage battery is also affected by the environment (such as its own temperature) and the load, for example, when the energy storage battery is fully charged, the high output voltage of the DC-DC converter will affect the life of the energy storage battery. Therefore, it is necessary to adapt the output voltage and output current of the photovoltaic array to the state of charge SOC of the energy storage battery, so that the working efficiency of the entire system can be effectively utilized to the greatest extent, and at the same time, the use of the energy storage battery can be taken into account. lifetime, so the present invention also uses a voltage protection or current protection mechanism.

Specifically, when the real-time state of charge SOC of the energy storage battery is in a fully charged state; that is, as long as it is judged that the real-time state of charge SOC of the energy storage battery is in a fully charged state, regardless of the output current of the DC-DC converter, priority Control the wireless energy supply system to enter the constant voltage output mode. As shown in Figure 1, the working mode of the wireless energy supply system is switched to the constant voltage output mode through the control mode decision module; the constant voltage output mode includes: adjusting the output voltage of the DC-DC converter, that is, through the pulse width modulation module ( PWM module) to adjust the duty ratio D of the DC-DC converter to adjust the output voltage of the DC-DC converter , so that the output voltage of the DC-DC converter It is the same as the full charge voltage of the energy storage battery.

In the above embodiment, when the real-time SOC of the energy storage battery is fully charged, switching the working mode of the wireless energy supply system to the constant voltage output mode is beneficial to protect the energy storage battery and improve the service life of the energy storage battery.

In an embodiment, the above step 202 further includes: when the real-time state of charge SOC of the energy storage battery is not in a fully charged state, and the real-time output current of the DC-DC converter When the charging current is higher than the safe charging current of the energy storage battery, the working mode of the wireless energy supply system is switched to the constant current output mode; the constant current output mode includes: adjusting the duty cycle of the DC-DC converter so that the DC-DC The output current of the converter is the same as the safe charging current of the energy storage battery.

Specifically, when the real-time state of charge SOC of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter When it is higher than the safe charging current of the energy storage battery, as shown in Figure 1, the working mode of the wireless energy supply system is switched to the constant current output mode through the control mode decision module; the constant current output mode includes: that is, through pulse width modulation The module (PWM module) adjusts the duty ratio D of the DC-DC converter to adjust the output current of the DC-DC converter , so that the output current of the DC-DC converter It is the same as the safe charging current of the energy storage battery.

In the above embodiment, when the real-time state of charge SOC of the energy storage battery is not fully charged, and the real-time output current of the DC-DC converter When the charging current is higher than the safe charging current of the energy storage battery, switching the working mode of the wireless energy supply system to the constant current output mode is beneficial to protect the energy storage battery and improve the service life of the energy storage battery.

In an embodiment, the above-mentioned maximum power tracking mode further includes: using the duty cycle of the DC-DC converter as the position variable of each particle in the particle swarm, using the particle swarm optimization algorithm based on the predator search strategy for each particle Iteratively calculate the position variable of the particle swarm to obtain the global optimal position of the particle swarm; based on the global optimal position (that is, the optimal duty cycle), the output voltage of the photovoltaic array and the corresponding maximum output power are calculated.

Among them, the PSO (Particle Swarm Optimization, particle swarm optimization) algorithm first initializes a group of particles in the feasible solution space, and each particle represents a potential optimal solution of the extreme value optimization problem. The item index represents the characteristic of the particle. Particles move in the solution space, and update the individual position by tracking the individual extremum (individual optimal position) and group extremum (group optimal position). , the population extremum refers to the corresponding position when all particles in the population search for the best fitness. Every time the particle updates its position, the fitness value is calculated, and the individual extremum and the group extremum are updated by comparing the fitness value of the particle, the individual extremum, and the group extremum.

Specifically, the present invention uses a particle swarm optimization algorithm (PS-PSO, PredatorySearch-Particle Swarm Optimization) based on a predator search strategy to realize the tracking of the maximum output power point of the photovoltaic array. For specific procedures, see the steps below.

In one embodiment, as shown in FIG. 5, FIG. 5 shows a schematic diagram of the control flow of the above-mentioned maximum power tracking mode, including:

Step 501, determine the global search space of the duty ratio of the DC-DC converter, and divide the global search space into multiple subspaces of different levels.

Since this application uses an improved particle swarm optimization algorithm, that is, the particle swarm optimization algorithm PS-PSO based on the predator search strategy. When optimizing the predatory search strategy, first conduct a global search in the entire search space until a better solution is found; then conduct a concentrated search in the area near the better solution, if the search does not find a better solution for many times, then give up the local area Search; then conduct a global search in the entire search space, and so on, until the optimal solution (or an approximate optimal solution) is found. Specifically, before initializing the population size, it is necessary to first determine the global search space of the particle's position variable ; the global search space Divide into subspaces that do not overlap with each other, and determine the level of these subspaces according to the adjacency relationship of these subspaces , get subspaces of different levels ; As shown in Figure 6, the subspace The neighborhood subspace of is , The neighborhood subspace of is ……So on and so forth.

Step 502, determine the subspace of the current level to be searched.

Specifically, for example to determine is the subspace to be searched, and the current level is 1.

Step 503, obtain an initial value in the subspace of the current level; the initial value includes the size of the particle swarm, the initial velocity of each particle in the particle swarm, and each The initial position of the particle.

As shown in Figure 7, Figure 7 shows another flow chart of the PS-PSO algorithm, and in conjunction with Figure 7, the PS-PSO algorithm is described in detail: it is determined that the current restricted area to be searched is after Initialize m particles within; specifically, initialize the population size m of the particle swarm, that is, there are m particles in total, and the initial position of each particle is the subspace of the current level Any value within , and at the same time, get the initial velocity of each particle.

Step 504, perform iterative optimization in the subspace of the current level, and update the local optimal solution in each iteration (that is, in the current subspace The group optimal position within ) until a better solution is obtained within the preset maximum number of iterations.

Among them, the above local optimal solution That is, the entire particle swarm in the current subinterval The group extremum (that is, the optimal position of the group) that can be found within.

Specifically, as shown in Figure 7, iterative optimization is performed through the PSO algorithm: in the current restricted area Inside, in the current iteration, update the speed and position of each particle, calculate the current corresponding fitness value of the particle through the preset fitness function, and judge whether the current fitness value is less than or greater than (the individual fitness value judgment conditions can be determined according to the actual situation) If the fitness value corresponding to the last optimal position of the individual is obtained, if the preset fitness value judgment condition is satisfied, the current position is taken as the optimal position of the individual, otherwise it remains unchanged; the fitness value corresponding to each particle in the entire particle swarm is calculated, and the selection Among them, the minimum or maximum fitness value, if the fitness value is less than or greater than (according to the actual situation to determine the group fitness value judgment condition) the fitness value corresponding to the last optimal position of the group, then the particle position corresponding to the individual fitness value is taken as the group’s optimal position. If the optimal position of the group is not met, the optimal position of the group remains unchanged, and the number of iterations is increased by 1 to enter the next round of iteration until the number of iterations is reached, and the iteration is terminated to obtain the current subinterval The group optimal position in (i.e. a more optimal solution).

Step 505, judge whether the above-mentioned better solution satisfies the preset historical extreme value judgment condition (for example, greater than or smaller than the last stored historical optimal solution), and if so, take the above-mentioned better solution as the historical optimal solution ( ); if not, keep the last historical optimal solution unchanged. The level is updated according to the level relationship, and the current subspace after the level update is obtained; return to step 502 .

Specifically, take the better solution as the historical optimal solution, update the level according to the hierarchical relationship, and obtain the current subspace after the updated level, and execute steps 502-505 in a loop until the restriction level reaches the preset level, then the currently obtained historical best Excellent solution as a global search space The global optimal solution on , that is, the duty cycle corresponding to the global maximum power point.

Specifically, if in Iteration of PSO Algorithm under Restricted Level If no better solution is found after times, the restriction level is adjusted to , and so on, when the restriction level reaches a certain value, if it is still impossible to update the historical optimal solution , then fall into the local optimal situation, in order to reduce the search time and jump out of the local optimal, the search area level must be adjusted to a higher level to jump out of the local search. Loop forward with this search strategy until the restriction level reaches , that is, the global restricted area. At this time, the search task is completed, and the historical optimal solution obtained is That is, the global optimal solution on the space Ω, that is, the global maximum power point.

In the above embodiment, the search process of the particle position is realized through the PS-PSO algorithm, which reduces the time for invalid search, thereby speeding up the convergence speed of the algorithm and reducing the probability of the algorithm falling into a local optimal solution, thereby improving the efficiency of the entire wireless energy supply system. The high operating efficiency enables the wireless energy supply system to quickly track to the maximum power point when it is disturbed or switches working modes, and improves the dynamic performance and stability of the wireless energy supply system.

In an embodiment, after the above step 201, it also includes: after using a preset weight function to perform a weighted comparison of the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery, according to the comparison result Determine the state conditions that the photovoltaic array wireless energy supply system satisfies.

Specifically, as shown in Figure 8, Figure 8 shows the adaptive closed-loop controller in the wireless energy supply system Schematic diagram of the structure of the photovoltaic cell, since the operating characteristics of the photovoltaic cell are nonlinear, its operating characteristic curves are shown in Figure 3 (a) and Figure 3 (b). In order to make it work near the maximum power point, the present invention uses a linear weighted compensator To realize the closed-loop stable control of photovoltaic arrays under different working conditions, the linear weighted compensator includes a weight function, where the weight function can output a decimal between 0 and 1 as the weight value, and the weight function is based on the input voltage of the DC-DC converter V _pv , the difference e between the maximum power reference voltage V _ref and the input voltage V _pv of the DC-DC converter calculates the weights w ₁ , w ₂ and w ₃ in the linear weighted compensator, and based on , , The weighted sum judgment control mode with the corresponding weights, where, , , They are PID controllers (Proportion Integration Differentiation, proportional-integral-differential controller).

In the above embodiment, according to the characteristics of the output characteristics of photovoltaic cells in different working areas, a linear weighted compensator is designed to adaptively compensate the nonlinear output of photovoltaic cells, so that the photovoltaic cells are disturbed (such as light changes) or in the working mode switching The dynamic performance and stability of photovoltaic cells can be guaranteed at the same time, and then it can be adapted to the closed-loop control when different disturbances appear in the maximum power tracking control mode.

A specific application of the above-mentioned wireless energy supply system is described below:

Since the output voltage and current of a single photovoltaic cell are small, in practical applications, photovoltaic cell units are usually combined in series and parallel to increase the output voltage and current capabilities of the photovoltaic system. In a specific verification case of the present invention, four groups of photovoltaic battery modules are selected to be connected in series, as shown in FIG. 9 . The parameters ( V _oc , I _sc , V _mpp , I _mpp ) of each group of photovoltaic cell components are shown in Table 1. The circuit model of the laser wireless energy supply system is built based on the interleaved parallel Boost converter, and the effectiveness of the closed-loop control algorithm and the maximum power tracking algorithm are experimentally verified. Among them, the Boost converter is one of the DC-DC converters. The specific circuit structure As shown in Figure 10.

Table 1 MPPT algorithm simulation system parameters

It can be seen from the simulation that when the output characteristics of the photovoltaic cell array are under the four conditions of single peak, two peaks, three peaks and four peaks, the running result of the maximum power tracking algorithm designed by the present invention is shown in Figure 11 . It can be seen from the figure that the global multi-peak maximum power tracking algorithm designed in the present invention can realize the global maximum power tracking of photovoltaic cells under different output conditions.

In order to verify the dynamic performance of the laser wireless energy supply system when the system illumination changes, and the effectiveness of the closed-loop control algorithm and the maximum power tracking algorithm for system stability control when switching between different working states. Dynamically change the output characteristics of photovoltaic cells at different times, that is, the output of photovoltaic cells is sequentially switched from single-peak to four-peak, the output power, output voltage (that is, the input voltage of the DC-DC converter) and output current of the photovoltaic array (That is, the input current of the DC-DC converter) The dynamic changes are shown in Figure 12(a), Figure 12(b) and Figure 12(c) respectively. It can be seen from the figure that the closed-loop control algorithm and the global multi-peak maximum power tracking algorithm designed by the present invention have good control performance and can satisfy the stable control of the system under large signal disturbance.

Figure 13 illustrates a schematic diagram of the physical structure of an electronic device, as shown in Figure 13, the electronic device may include: a processor (processor) 1310, a communication interface (Communications Interface) 1320, a memory (memory) 1330 and a communication bus 1340, Wherein, the processor 1310 , the communication interface 1320 , and the memory 1330 communicate with each other through the communication bus 1340 . The processor 1310 can call the logic instructions in the memory 1330 to execute a closed-loop control method or a maximum power tracking method. The above-mentioned closed-loop control method includes: monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time charge of the energy storage battery. Power state: According to the state conditions satisfied by the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery, the working mode of the wireless energy supply system is determined. The above maximum power tracking method includes: monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery; when the real-time state of charge of the energy storage battery is not fully charged state, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, it is determined that the working mode of the wireless energy supply system is the maximum power tracking mode; the maximum power tracking The mode includes: adjusting the duty ratio of the DC-DC converter to change the output power of the photovoltaic array until the output power of the photovoltaic array reaches the maximum output power under the current environment state.

In addition, the above-mentioned logic instructions in the memory 1330 may be implemented in the form of software function units and may be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes. .

On the other hand, the present invention also provides a computer program product. The computer program product includes a computer program that can be stored on a non-transitory computer-readable storage medium. When the computer program is executed by a processor, the computer can Executing the closed-loop control method or maximum power tracking method provided by the above-mentioned methods, the above-mentioned closed-loop control method includes: monitoring the real-time output voltage of the DC-DC converter, the real-time output current and the real-time state of charge of the energy storage battery; according to the DC-DC The state conditions satisfied by the real-time output voltage, real-time output current of the converter and the real-time charge state of the energy storage battery determine the working mode of the wireless energy supply system. The above maximum power tracking method includes: monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery; when the real-time state of charge of the energy storage battery is not fully charged state, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, it is determined that the working mode of the wireless energy supply system is the maximum power tracking mode; the maximum power tracking The mode includes: adjusting the duty ratio of the DC-DC converter to change the output power of the photovoltaic array until the output power of the photovoltaic array reaches the maximum output power under the current environment state.

In yet another aspect, the present invention also provides a non-transitory computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it is implemented to execute the closed-loop control method or the maximum power tracking method provided by the above-mentioned methods , the above-mentioned closed-loop control method includes: monitoring the real-time output voltage of the DC-DC converter, the real-time output current and the real-time state of charge of the energy storage battery; The state conditions satisfied by the real-time state of charge determine the working mode of the wireless energy supply system. The above maximum power tracking method includes: monitoring the real-time output voltage and real-time output current of the DC-DC converter and the real-time state of charge of the energy storage battery; when the real-time state of charge of the energy storage battery is not fully charged state, and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, it is determined that the working mode of the wireless energy supply system is the maximum power tracking mode; the maximum power tracking The mode includes: adjusting the duty ratio of the DC-DC converter to change the output power of the photovoltaic array until the output power of the photovoltaic array reaches the maximum output power under the current environment state.

The system embodiments described above are only illustrative, and the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed to multiple network elements. Part or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment. It can be understood and implemented by those skilled in the art without any creative efforts.

Through the above description of the implementations, those skilled in the art can clearly understand that each implementation can be implemented by means of software plus a necessary general hardware platform, and of course also by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the prior art can be embodied in the form of software products, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic CD, CD, etc., including several instructions to make a computer device (which may be a personal computer, server, or network device, etc.) execute the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or equivalent replacements are made to some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims (16)

1. The wireless energy supply system is characterized by comprising a photovoltaic array, a DC-DC converter and an energy storage battery; the photovoltaic array is connected with the energy storage battery through the DC-DC converter; the DC-DC converter comprises a main control chip; wherein,,

the main control chip is used for monitoring the real-time output voltage and the real-time output current of the DC-DC converter and the real-time charge state of the energy storage battery;

the main control chip is also used for determining the working mode of the wireless energy supply system according to the real-time output voltage and the real-time output current of the DC-DC converter and the state conditions met by the real-time state of charge of the energy storage battery.

2. The wireless power supply system of claim 1 wherein said master control chip includes a maximum power tracking mode control loop; the working modes comprise a maximum power tracking mode;

the maximum power tracking mode control loop is further configured to determine that the working mode of the wireless energy supply system is a maximum power tracking mode when the real-time state of charge of the energy storage battery is not in a full state and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery;

the maximum power tracking mode includes: and adjusting the duty ratio of the DC-DC converter to change the output power of the photovoltaic array until the output power of the photovoltaic array reaches the maximum power in the current state.

3. The wireless energy supply system of claim 1, wherein the master control chip comprises a constant voltage output mode control loop; the working mode comprises a constant voltage output mode;

the constant voltage output mode control loop is used for switching the working mode into a constant voltage output mode when the real-time state of charge of the energy storage battery is in a full state;

The constant voltage output mode includes: and adjusting the output voltage of the DC-DC converter so that the output voltage of the DC-DC converter is the same as the full-charge voltage of the energy storage battery.

4. The wireless energy supply system of claim 1, wherein the main control chip comprises a constant current output mode control loop, and the working mode comprises a constant current output mode;

the constant current output mode control loop is used for switching the working mode of the wireless energy supply system into a constant current output mode when the real-time charge state of the energy storage battery is not in a full charge state and the real-time output current of the DC-DC converter is higher than the safe charging current of the energy storage battery; the constant current output mode includes: the duty cycle of the DC-DC converter is adjusted such that the output current of the DC-DC converter is the same as the safe charging current of the energy storage battery.

5. The wireless power supply system of any one of claims 1 to 4, wherein said system further comprises a laser emitting end; wherein,,

the laser emission end is used for emitting laser to the photovoltaic array so that the photovoltaic array converts laser energy into first voltage and outputs the first voltage to the DC-DC converter;

The DC-DC converter is used for converting the first voltage into a second voltage so as to enable the energy storage battery to store electric energy.

6. A closed loop control method applied to the wireless power supply system according to any one of claims 1 to 5, comprising:

monitoring a real-time output voltage, a real-time output current of the DC-DC converter and a real-time state of charge of the energy storage battery;

and determining the working mode of the wireless energy supply system according to the state conditions met by the real-time output voltage, the real-time output current and the real-time state of charge of the energy storage battery of the DC-DC converter.

7. The method of claim 6, wherein determining the operating mode of the wireless energy supply system based on the state conditions satisfied by the real-time output voltage, the real-time output current, and the real-time state of charge of the energy storage battery of the DC-DC converter comprises:

when the real-time state of charge of the energy storage battery is in a full-charge state, switching the working mode of the wireless energy supply system into a constant-voltage output mode; the constant voltage output mode includes: the duty cycle of the DC-DC converter is adjusted so that the output voltage of the DC-DC converter is the same as the full charge voltage of the energy storage battery.

8. The closed loop control method of claim 6, comprising:

when the real-time charge state of the energy storage battery is not in a full-charge state and the real-time output current of the DC-DC converter is higher than the safe charging current of the energy storage battery, switching the working mode of the wireless energy supply system into a constant-current output mode; the constant current output mode includes: and adjusting the duty ratio of the DC-DC converter so that the output current of the DC-DC converter is the same as the safe charging current of the energy storage battery.

9. A maximum power tracking method applied to the wireless energy supply system according to any one of claims 1 to 5, comprising:

monitoring a real-time output voltage, a real-time output current of the DC-DC converter and a real-time state of charge of the energy storage battery;

when the real-time state of charge of the energy storage battery is not in a full-charge state and the real-time output current of the DC-DC converter is not higher than the safe charging current of the energy storage battery, determining that the working mode of the wireless energy supply system is a maximum power tracking mode; the maximum power tracking mode includes: and adjusting the duty ratio of the DC-DC converter to change the output power of the photovoltaic array until the output power of the photovoltaic array reaches the maximum output power in the current environment state.

10. The maximum power tracking method of claim 9, wherein the maximum power tracking mode further comprises:

taking the duty ratio of the DC-DC converter as a position variable of particles in a particle swarm, and iteratively updating the position variable of the particles by using a particle swarm optimization algorithm based on predation search strategy to obtain a global optimal position of the particle swarm;

and calculating the output voltage of the photovoltaic array based on the global optimal position, and obtaining the maximum output power of the wireless energy supply system corresponding to the output voltage in the current environment state.

11. The maximum power tracking method of claim 9, wherein the maximum power tracking mode further comprises:

determining a global search space of a duty cycle of the DC-DC converter, and dividing the global search space into a plurality of subspaces of different levels;

determining a subspace of a current level to be searched;

initializing a particle swarm scale and a maximum iteration number in the subspace of the current level;

performing iterative optimization in the subspace of the current level, and updating a local optimal solution according to a preset fitness function until a better solution is obtained within a preset maximum iteration number;

Taking the better solution as a historical optimal solution, and updating the level according to the level relation to obtain an updated subspace of the current level; and returning to the step of determining the subspace of the current level to be searched.

12. The maximum power tracking method as claimed in claim 11, further comprising:

if no better solution exists in the preset maximum iteration times, updating the level according to the level relation, obtaining an updated subspace of the current level, returning to the subspace of the current level to be searched, until the updated level reaches the preset level, and outputting the current obtained historical optimal solution;

and taking the currently obtained historical optimal solution as a global optimal solution in the global search space.

13. The method of any one of claims 9 to 12, wherein after monitoring the real-time output voltage, the real-time output current, and the real-time state of charge of the energy storage battery of the DC-DC converter, further comprising:

and after the real-time output voltage and the real-time output current of the DC-DC converter and the real-time charge state of the energy storage battery are subjected to weighted comparison by using a preset weight function, judging the state condition met by the photovoltaic array wireless energy supply system according to the comparison result.

14. An electronic device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, characterized in that the processor implements the closed loop control method according to any one of claims 6 to 8 or the maximum power tracking method according to any one of claims 9 to 13 when executing the program.

15. A non-transitory computer readable storage medium having stored thereon a computer program, wherein the computer program when executed by a processor implements the closed loop control method of any of claims 6 to 8 or the maximum power tracking method of any of claims 9 to 13.

16. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements the closed loop control method of any of claims 6 to 8 or the maximum power tracking method of any of claims 9 to 13.

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