A self-balancing loss-reducing and efficiency-increasing system for photovoltaic module power generation connection

Abstract

The present application relates to photovoltaic power generation loss reduction technical field, especially to a kind of for photovoltaic module power generation connection self-balancing loss reduction efficiency increasing system, including photovoltaic module, balancing module, information acquisition module, control module and output module, photovoltaic module provides completed closed photovoltaic circuit, balancing module stores the excess power generated by photovoltaic module, and issues excess power to the photovoltaic module to be compensated, information acquisition module detects the working parameter of photovoltaic module, obtains the power storage capacity in balancing module and the working parameter of balancing module, control module determines power generation fluctuation characteristic parameter to determine whether to compensate photovoltaic module with electric energy, determines whether to carry out output efficiency increasing according to power storage capacity and efficiency increasing mode, and sends control instruction to balancing module, output module is used to output final electric energy, the present application improves electric energy utilization efficiency, effectively balances the output current of each photovoltaic module, improves system power generation efficiency and stability.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photovoltaic power generation loss reduction, and particularly relates to a self-balancing loss reduction and efficiency increasing system for photovoltaic module power generation connection. BACKGROUND

[0002] Photovoltaic power generation technology has become an important direction of global renewable energy application by directly converting solar energy into electricity through photovoltaic effect. Traditional photovoltaic systems mostly adopt a string structure, that is, multiple photovoltaic modules are connected in series and then connected to a centralized inverter. In actual engineering applications, the string structure widely used in traditional photovoltaic systems exposes significant technical bottlenecks. Multiple photovoltaic modules are connected in series to form high-voltage direct current output, which can reduce line loss and adapt to centralized inverters, but is subject to inherent differences between modules and external environmental disturbances (such as local shading, dust coverage, temperature gradient, etc.). The output current of the entire string is forced to match the current value of the weakest module, resulting in serious "mismatch loss" of the system. Studies have shown that in a string containing 10% of the shadow, the system efficiency loss can reach 18% to 25%; if the aging difference of the modules exceeds 15%, the annual power generation loss will exceed 30%.

[0003] To address this problem, the industry has proposed string optimizer (such as Tigo's TS4 series) and micro-inverter (Enphase IQ8, etc.) solutions. The former achieves local maximum power point tracking (MPPT) by configuring an independent DC-DC conversion circuit for each module, which can eliminate mismatch but increases the system cost by 30% to 50%. The latter achieves AC conversion at the module level and completely decouples the series dependency, but its power density limitation makes it economically unfeasible in large ground power stations. SUMMARY

[0004] The purpose of the present application is to provide a self-balancing loss reduction and efficiency increasing system for photovoltaic module power generation connection, which can solve the problem of low photovoltaic power generation efficiency and poor balance caused by the worst photovoltaic panel affecting the entire photovoltaic power generation system.

[0005] To this end, the present application provides a self-balancing loss reduction and efficiency increasing system for photovoltaic module power generation connection, which comprises:

[0006] a photovoltaic module comprising a plurality of series-connected photovoltaic components to form a complete closed photovoltaic circuit;

[0007] a balancing module connected to the photovoltaic module to adjust the operating parameters of each photovoltaic component, store excess power generated by the photovoltaic component, and supply excess power to the photovoltaic component that needs compensation;

[0008] an information collection module connected to the photovoltaic module and the balancing module, for detecting working parameters of each photovoltaic component, obtaining an electric energy storage amount of the excess electric energy in the balancing module, detecting an electric quantity output parameter and an output time of the balancing module, and determining the photovoltaic component to be compensated according to the working parameters of each photovoltaic component;

[0009] a control module connected to the balancing module and the information collection module, for determining a power generation fluctuation characteristic parameter according to the working parameters of the non-compensated photovoltaic component to determine whether the photovoltaic component needs to be compensated, determining whether to output the efficiency of all photovoltaic components according to the electric energy storage amount, determining an efficiency mode according to the electric quantity output parameter and the output time, and sending a control instruction to the balancing module;

[0010] an output module connected to the photovoltaic module, the balancing module and the information collection module, for outputting final electric energy.

[0011] As a preferred technical solution for the photovoltaic component power generation connection self-balancing loss reduction and efficiency increasing system, the balancing module comprises:

[0012] an input power interface connected to the photovoltaic component in the photovoltaic module;

[0013] an amplification circuit unit connected to the input power interface, for processing the excess electric energy to obtain compensation electric energy;

[0014] a lithium ion capacitor pre-storage unit connected to the amplification circuit unit, for storing the excess electric energy generated by the photovoltaic component;

[0015] a lithium ion capacitor output unit connected to the lithium ion capacitor pre-storage unit and the photovoltaic component, for outputting the compensation electric energy to the photovoltaic component to be compensated.

[0016] As a preferred technical solution for the photovoltaic component power generation connection self-balancing loss reduction and efficiency increasing system, the electric quantity output parameter detected by the information collection module comprises: a compensation target photovoltaic component and a compensation current value of the compensation target photovoltaic component;

[0017] The output time detected by the information collection module comprises: a start time and an end time of all compensation current values of each compensation target photovoltaic component.

[0018] As a preferred technical solution for the photovoltaic component power generation connection self-balancing loss reduction and efficiency increasing system, the information collection module determines the photovoltaic component to be compensated according to the working parameters of each photovoltaic component, comprising:

[0019] If the difference between the output current of the current photovoltaic module and the output current of any other photovoltaic module is greater than the individual compensation threshold, the current photovoltaic module is the compensation-required photovoltaic module.

[0020] As a preferred technical solution for the photovoltaic module power generation connection self-balancing loss reduction and efficiency increasing system, the control module determines the power generation fluctuation characteristic parameter according to the working parameters of the non-compensation photovoltaic module, which includes:

[0021] The control module calculates the average value of the output currents of all non-compensation photovoltaic modules and the average deviation of the output currents of all non-compensation photovoltaic modules, and determines the power generation fluctuation characteristic parameter according to the average deviation of the output currents and the average value of the output currents.

[0022] As a preferred technical solution for the photovoltaic module power generation connection self-balancing loss reduction and efficiency increasing system, the control module determines whether the remaining photovoltaic modules need to be compensated for electric energy according to the power generation fluctuation characteristic parameter,

[0023] If the power generation fluctuation characteristic parameter is greater than the standard fluctuation characteristic parameter, the control module determines that the remaining photovoltaic modules need to be compensated for electric energy;

[0024] If the power generation fluctuation characteristic parameter is less than or equal to the standard fluctuation characteristic parameter, the control module determines that the remaining photovoltaic modules do not need to be compensated for electric energy.

[0025] As a preferred technical solution for the photovoltaic module power generation connection self-balancing loss reduction and efficiency increasing system, the control module is configured to determine whether to increase the output of all photovoltaic modules in response to the determination that the remaining photovoltaic modules do not need to be compensated for electric energy in combination with the amount of stored electric energy, specifically including:

[0026] If the amount of stored electric energy is greater than the electric energy demand of the compensation-required photovoltaic module, the control module determines to increase the output of all photovoltaic modules;

[0027] If the amount of stored electric energy is less than or equal to the electric energy demand of the compensation-required photovoltaic module, the control module determines not to increase the output of all photovoltaic modules.

[0028] As a preferred technical solution for the photovoltaic module power generation connection self-balancing loss reduction and efficiency increasing system, the control module determines the efficiency increasing mode according to the electric energy output parameter and the output time, which includes:

[0029] The control module performs first electric energy compensation for the photovoltaic modules with output currents lower than the maximum output current using all the stored electric energy;

[0030] If there is remaining stored electric energy, the remaining stored electric energy is equally compensated to all photovoltaic modules for second electric energy compensation;

[0031] If there is no remaining energy storage, the duration of the first energy efficiency compensation this time is determined according to the output time of the photovoltaic module to be compensated.

[0032] As a preferred technical solution for the photovoltaic module power generation connection self-balancing loss reduction and efficiency improvement system, the control instructions sent by the control module to the balancing module include: photovoltaic module compensation instructions, first energy efficiency compensation instructions and second energy compensation instructions:

[0033] Each compensation instruction contains the energy compensation amount of each photovoltaic module.

[0034] The beneficial effects of the present application are:

[0035] The present application effectively solves the output mismatch problem caused by individual differences and environmental factors when photovoltaic modules are connected in series through precise monitoring and intelligent control, accurately identifies the components that need to be compensated by real-time monitoring of the working parameters of each photovoltaic module, and stores and distributes excess energy through the balancing module to achieve precise compensation of the components that need to be compensated. At the same time, the system calculates the power fluctuation characteristic parameters to dynamically determine whether further energy compensation or overall efficiency improvement is needed. In addition, the system reasonably decides the overall efficiency improvement method according to the comparison of energy storage and demand, avoids overcompensation or undercompensation, improves energy utilization efficiency, effectively balances the output current of each photovoltaic module, improves system power generation efficiency and stability, prolongs the service life of the module, reduces maintenance costs, enhances the adaptability and reliability of the photovoltaic system under different light conditions, and realizes loss reduction and efficiency improvement of the photovoltaic power generation system.

[0036] Especially in the present application, the series mismatch caused by manufacturing deviation, aging degree and light factors of photovoltaic modules is fully considered, and the corresponding compensation mechanism is determined accordingly, which can effectively balance the output current of each photovoltaic module, improve the power generation efficiency and stability of the entire photovoltaic system. At the same time, this compensation strategy based on actual working parameters helps to prolong the service life of photovoltaic modules, reduce system maintenance costs, and improve the overall performance and economic benefits of distributed photovoltaic power generation systems.

[0037] Especially, in the present application, the control module calculates the average value and average deviation of the output current of the non-compensated photovoltaic module in real time, determines the power generation fluctuation characteristic parameter, and compares it with the standard fluctuation characteristic parameter determined based on historical data, to intelligently determine whether other photovoltaic modules need to be compensated for electric energy, and to ensure accurate and effective compensation decision when the light condition changes. When compensation is needed, the photovoltaic modules are selected in order of output current from small to large, the photovoltaic modules that need secondary compensation are determined, and the photovoltaic modules that need compensation and the secondary compensation modules are compensated synchronously. In addition, the electric energy is reasonably distributed according to the system charging state and the total energy capacity to avoid over-compensation or under-compensation, effectively balance the output current of each photovoltaic module, improve the power generation efficiency and stability, prolong the service life of the module, reduce the system maintenance cost, improve the overall performance and economic benefit of the photovoltaic system, and ensure efficient and reliable operation under different light conditions.

[0038] Especially, in the present application, the control module determines whether to start the overall efficiency based on the comparison of the electric energy storage amount and the module electric energy demand amount, avoids invalid energy consumption, effectively solves the problem of power loss of the whole string caused by the relatively low performance of individual modules by preferentially compensating the secondary compensation photovoltaic modules, and guarantees the basic power generation efficiency of the system. After completing the directional compensation, the average distribution strategy of the remaining electric energy further taps the overall power generation potential, realizing the step-by-step improvement of the system power generation power. At the same time, combined with the electric quantity output parameter and the output time, a hierarchical efficiency compensation mechanism is formulated to flexibly adjust the electric energy distribution and compensation time, which not only ensures that the key modules are fully compensated, but also maximizes the use of electric energy. Based on historical data, the compensation duration is determined, so that the system can adapt to different light conditions, significantly improve the stability and power generation efficiency of the photovoltaic system, and effectively achieve the purpose of loss reduction and efficiency improvement, optimizing the economic benefit and resource utilization rate of the photovoltaic power generation system. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 The structure diagram of the self-balancing loss reduction and efficiency improvement system for photovoltaic module power generation in the embodiment of the present application is shown.

[0040] Figure 2 The structure diagram of the balancing module in the embodiment of the present application is shown.

[0041] Figure 3 The logic diagram for determining whether the remaining photovoltaic modules need to be compensated for electric energy in the embodiment of the present application is shown. DETAILED DESCRIPTION

[0042] The technical solutions of the present application will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor belong to the scope of protection of the present application.

[0043] In the description of the present application, it should be noted that unless specifically defined and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0044] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference signs represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present application, and cannot be understood as a limitation of the present application.

[0045] Please refer to Figure 1 As shown in the structure schematic diagram of the self-balancing loss-reducing and efficiency-increasing system for photovoltaic module power generation in the embodiment of the present application, the present application provides a self-balancing loss-reducing and efficiency-increasing system for photovoltaic module power generation, comprising:

[0046] A photovoltaic module comprising a plurality of series-connected photovoltaic components to form a complete closed photovoltaic circuit;

[0047] A balancing module connected to the photovoltaic module to adjust the working parameters of each photovoltaic component, store the excess power generated by the photovoltaic component, and issue the excess power to the photovoltaic component to be compensated;

[0048] An information acquisition module connected to the photovoltaic module and the balancing module respectively to detect the working parameters of each photovoltaic component, obtain the power storage amount of the excess power in the balancing module, detect the power output parameters and output time of the balancing module, and determine the photovoltaic component to be compensated according to the working parameters of each photovoltaic component;

[0049] A control module connected to the balancing module and the information acquisition module respectively to determine the power generation fluctuation characteristic parameter according to the working parameters of the non-compensated photovoltaic component to determine whether the photovoltaic component needs to be compensated, determine whether to output the efficiency of all photovoltaic components according to the power storage amount, determine the efficiency mode according to the power output parameters and output time, and issue a control instruction to the balancing module;

[0050] An output module connected to the photovoltaic module, the balancing module and the information acquisition module respectively to output the final power.

[0051] In the implementation, the selection of the photovoltaic module is not specifically limited, which can be any one of existing photovoltaic power generation modules, such as a single-crystal silicon photovoltaic module, a multi-crystal silicon photovoltaic module, an HJT (heterojunction) photovoltaic module, a TOPCon photovoltaic module, etc., which will not be repeated here.

[0052] The specific structure of the control module is not limited, which can be composed of a logic component including a field programmable processor, a computer and a microprocessor in the computer.

[0053] The embodiment is preferably a 550WN type TOPCon bifacial photovoltaic module, and the photovoltaic module adopts 24 550WN type TOPCon bifacial modules in series, the open circuit voltage (Voc) of each module is 49.6V, the maximum power point voltage (Vmp) is 41.2V, the rated power of the system after series connection is 13.2kW, and the open circuit voltage reaches 1190V. The reliability design: the spacing between the modules is reserved with a 10mm thermal expansion gap, and a high-temperature-resistant MC4 connector (resistant to temperature-40℃~105℃) is configured.

[0054] The working parameters of the photovoltaic module include: output voltage, output current and output power, and the working parameters of the photovoltaic module are obtained through the photovoltaic module parameter tester.

[0055] The application effectively solves the output mismatch problem caused by individual differences and environmental factors when the photovoltaic modules are connected in series through accurate monitoring and intelligent control, accurately identifies the modules that need to be compensated by monitoring the working parameters of each photovoltaic module in real time, and stores and distributes the excess power through the balancing module to realize accurate compensation of the modules that need to be compensated. At the same time, the system calculates the power fluctuation characteristic parameters to dynamically determine whether further power compensation or overall efficiency improvement is needed. In addition, the system reasonably decides the overall efficiency improvement mode according to the comparison of the power storage amount and the demand amount, avoids overcompensation or undercompensation, improves the power utilization efficiency, effectively balances the output current of each photovoltaic module, improves the power generation efficiency and stability of the system, prolongs the service life of the module, reduces the maintenance cost, enhances the adaptability and reliability of the photovoltaic system under different light conditions, and realizes the loss reduction and efficiency improvement of the photovoltaic power generation system.

[0056] Please refer to Figure 2 As shown in the figure, it is a structure schematic diagram of the balancing module in the embodiment of the application, the balancing module comprises:

[0057] The input power interface is connected with the photovoltaic module in the photovoltaic module;

[0058] The amplification circuit unit is connected with the input power interface, and is used to process the excess power to obtain compensation power;

[0059] A lithium-ion capacitor pre-storage unit, which is connected to the amplifier circuit unit, is used to store the excess electrical energy generated by the photovoltaic module;

[0060] A lithium-ion capacitor output unit, which is connected to the lithium-ion capacitor pre-storage unit and the photovoltaic module, is used to output the compensation power to the photovoltaic module that needs compensation.

[0061] In implementation, the amplifier circuit unit collects the current generated by the photovoltaic module through a current transformer and outputs it to the amplifier circuit. After the amplifier circuit performs AD conversion on the signal, it outputs it to the intelligent computing circuit with the STM32 main control chip as the core in the control module. After the STM32 chip completes the calculation, the control module transfers the charge stored in the lithium-ion capacitor pre-store module to the lithium-ion capacitor output module by controlling the opening and closing of the relay through control commands.

[0062] The input power interface has the following electrical characteristics: rated current 15A, withstand voltage 1500VDC, and contact resistance less than 0.5mΩ.

[0063] The circuit topology of the balanced module adopts a four-phase interleaved Boost-Buck bidirectional converter architecture with a switching frequency of 100kHz, equipped with SiCMOSFETs, and a conversion efficiency greater than or equal to 98%.

[0064] The lithium-ion capacitor pre-storage unit consists of eight groups of 3.2V / 3000F lithium-ion capacitors (total capacity 25.6V / 375F), supports a maximum compensation current of ±5A, and its charge and discharge management adopts an active balancing strategy with a SOC balance error of less than 5%.

[0065] Specifically, the power output parameters detected by the information acquisition module include: the target photovoltaic module and the compensation current value of the target photovoltaic module;

[0066] The output time detected by the information acquisition module includes: the start time and end time of all compensation current values ​​of each compensation target photovoltaic module.

[0067] In implementation, the start and end times of the total compensation current values ​​of each target photovoltaic module are the start and end times of the compensation current values ​​of each photovoltaic module being compensated for.

[0068] It is understandable that the electrical energy collected by a single photovoltaic module will vary throughout the day with changes in sunlight intensity. Therefore, when compensating a photovoltaic module, the magnitude of the compensation current will change with the magnitude of the current generated by the photovoltaic module.

[0069] Specifically, the information acquisition module determines the photovoltaic modules requiring compensation based on the operating parameters of each photovoltaic module, including:

[0070] If the difference between the output current of the current photovoltaic module and the output current of any other photovoltaic module is greater than the individual compensation threshold, the current photovoltaic module is the compensation-required photovoltaic module.

[0071] In implementation, according to Distributed Photovoltaic Power Generation Engineering Technical Specification (DB11 / T 1773-2020), because of the series mismatch caused by the manufacturing deviation, aging degree, and illumination factors of the photovoltaic module. Generally, when the difference between the output currents of the modules exceeds 5%-8% of the rated output current, it will have a greater impact on the power generation efficiency, therefore, the individual compensation threshold in the implementation is 5%-8% of the rated output current.

[0072] The rated output current is the maximum output current of the photovoltaic module under standard test conditions, and the standard test conditions are generally: solar radiation intensity is 1000W / m 2 , cell temperature is 25℃, and atmospheric mass is 1.5 (AM1.5).

[0073] In the present application, the series mismatch caused by the manufacturing deviation, aging degree, and illumination factors of the photovoltaic module is fully considered, and the corresponding compensation mechanism is determined accordingly, which can effectively balance the output currents of the photovoltaic modules and improve the power generation efficiency and stability of the entire photovoltaic system. At the same time, this compensation strategy based on actual working parameters helps to prolong the service life of the photovoltaic module, reduce the system maintenance cost, and improve the overall performance and economic benefit of the distributed photovoltaic power generation system.

[0074] Specifically, the control module determines the power generation fluctuation representation parameter according to the working parameters of the non-compensation photovoltaic module.

[0075] The control module calculates the average value of the output currents of all non-compensation photovoltaic modules and the average deviation of the output currents of all non-compensation photovoltaic modules, and determines the power generation fluctuation representation parameter according to the average deviation of the output currents and the average value of the output currents.

[0076] In implementation, the power generation fluctuation representation parameter is determined according to the ratio of the average deviation of the output currents to the average value of the output currents.

[0077] The control module determines the average value of the output currents of the non-compensation photovoltaic modules and the average deviation of the output currents of the non-compensation photovoltaic modules under the current illumination condition in real time, and the determined power generation fluctuation representation parameter is only effective for the current illumination condition.

[0078] Please refer to Figure 3 , which is a logic diagram for determining whether the remaining photovoltaic modules need to be compensated for electric energy in the embodiment of the present application, and the control module determines whether the remaining photovoltaic modules need to be compensated for electric energy according to the power generation fluctuation representation parameter,

[0079] If the power generation fluctuation characteristic parameter is greater than the standard fluctuation characteristic parameter, the control module determines that power compensation is needed for the remaining photovoltaic components;

[0080] If the power generation fluctuation characteristic parameter is less than or equal to the standard fluctuation characteristic parameter, the control module determines that power compensation is not needed for the remaining photovoltaic components.

[0081] In implementation, the standard fluctuation characteristic parameter is determined according to the sum of the average value of the fluctuation characteristic parameters of the photovoltaic components that have not been compensated for power of the remaining photovoltaic components and 2 times the standard deviation in the historical data.

[0082] If power compensation is needed for the remaining photovoltaic components, the photovoltaic components are excluded one by one from the beginning in the order of decreasing output current, the power generation fluctuation characteristic parameter of the current photovoltaic component is not included in the calculation, until the last calculated power generation fluctuation characteristic parameter is less than or equal to the standard fluctuation characteristic parameter, and according to the calculation results of each standard fluctuation characteristic parameter, the photovoltaic components with all calculation results greater than the standard fluctuation characteristic parameter are recorded as secondary compensation photovoltaic components.

[0083] The power storage amount allocation formula is:

[0084]

[0085] Wherein, m is the number of secondary compensation photovoltaic components, E alloc is the actual allocated power storage amount, SOC (State of Charge) is the state of charge (percentage) of the system, for example, the proportion of the current remaining power of the battery to the total capacity, E total is the total energy capacity of the lithium ion capacitor pre-storage unit (such as the total capacity of the battery), E demandi is the energy demand of the i-th demand point, is the total energy demand of all demand points.

[0086] It can be understood that when the secondary compensation photovoltaic components are compensated for power, the compensation photovoltaic components will be compensated synchronously to avoid the current of the compensation photovoltaic components being lower than that of the compensated photovoltaic components, resulting in invalidation of the efficiency improvement.

[0087] In the present application, the control module calculates the average value and average deviation of the output current of the non-compensated photovoltaic module in real time, determines the power generation fluctuation characteristic parameter, and compares it with the standard fluctuation characteristic parameter determined based on historical data to intelligently determine whether other photovoltaic modules need to be compensated for electric energy. When the light condition changes, the compensation decision is accurate and effective. When compensation is needed, the photovoltaic modules are selected in order from small to large output current, and the photovoltaic modules that need secondary compensation are determined, and the photovoltaic modules that need compensation and the secondary compensation modules are compensated synchronously. In addition, the system charging state and total energy capacity are reasonably allocated to avoid overcompensation or undercompensation, effectively balance the output current of each photovoltaic module, improve the power generation efficiency and stability, prolong the service life of the module, reduce the system maintenance cost, improve the overall performance and economic benefit of the photovoltaic system, and ensure efficient and reliable operation under different light conditions.

[0088] Specifically, the control module is configured to determine whether to perform output efficiency enhancement on all photovoltaic modules in response to the remaining photovoltaic modules not needing electric energy compensation in combination with the electric energy storage amount, specifically including:

[0089] If the electric energy storage amount is greater than the electric energy demand amount of the photovoltaic modules that need compensation, the control module determines to perform output efficiency enhancement on all photovoltaic modules.

[0090] If the electric energy storage amount is less than or equal to the electric energy demand amount of the photovoltaic modules that need compensation, the control module determines not to perform output efficiency enhancement on all photovoltaic modules.

[0091] In the present embodiment, the electric energy demand amount is determined according to the difference between the current minimum value of all secondary compensation photovoltaic modules and the photovoltaic modules that have not been compensated.

[0092] It can be understood that the control module monitors the output current of each component in the photovoltaic string in real time, identifies the secondary compensation photovoltaic components that need compensation, and preferentially directs the available electric energy of the energy storage system to these components, thereby increasing the output to near normal level by injecting additional current, thereby alleviating the loss of the entire string power caused by the performance decline of individual components; if there is remaining electric energy after completing the directional compensation, the remaining electric energy is evenly distributed to all components in the string to further improve the overall output power.

[0093] Specifically, the control module determines the efficiency enhancement mode according to the electric quantity output parameter and the output time, including:

[0094] The control module performs first electric energy efficiency compensation on the photovoltaic modules with output current lower than the maximum output current using all the electric energy storage amount.

[0095] If there is remaining electric energy storage, the remaining electric energy storage is evenly distributed to all photovoltaic modules for second electric energy efficiency compensation.

[0096] If there is no remaining energy storage, the duration of the first energy efficiency compensation this time is determined according to the output time of the compensation to the photovoltaic module to be compensated.

[0097] In implementation, the power output parameter includes the current value of the secondary compensation photovoltaic module, and the output time also includes the start time and the end time of the total compensation current value of the secondary compensation photovoltaic module.

[0098] It can be understood that the compensation current of the secondary compensation photovoltaic module is usually smaller than the directly determined photovoltaic module to be compensated, but in fact, the energy compensation is actually performed on the secondary compensation photovoltaic module, and therefore, the information acquisition module detects the power output parameter and the output time of the balancing module, which contains the information of the secondary compensation photovoltaic module.

[0099] The duration of the first energy efficiency compensation this time according to the output time of the compensation to the photovoltaic module to be compensated is the duration of the compensation current for the energy compensation to the photovoltaic module to be compensated under the same light condition according to the historical data.

[0100] In the present application, the control module accurately decides whether to start the overall efficiency according to the comparison between the energy storage amount and the component energy demand amount, avoids invalid energy consumption, effectively solves the problem of power loss of the whole string caused by the relatively poor performance of individual components by preferentially compensating the secondary compensation photovoltaic module, and guarantees the basic power generation efficiency of the system; after completing the directional compensation, the average distribution strategy of the remaining energy further excavates the overall power generation potential, and realizes the step-by-step improvement of the system power generation power. At the same time, the layered efficiency compensation mechanism is formulated combined with the power output parameter and the output time, and the power distribution and compensation time is flexibly adjusted, which not only ensures that the key components are fully compensated, but also realizes the maximum utilization of energy. The compensation duration is determined based on the historical data, so that the system can adapt to different light conditions, significantly improve the stability and power generation efficiency of the photovoltaic system, and effectively achieve the purpose of loss reduction and efficiency improvement, and optimize the economic benefit and resource utilization rate of the photovoltaic power generation system.

[0101] Specifically, the control instruction issued by the control module to the balancing module includes: photovoltaic module compensation instruction, first energy efficiency compensation instruction and second energy compensation instruction.

[0102] Each compensation instruction contains the energy compensation amount of each photovoltaic module.

[0103] In the present embodiment, the process of generating and issuing instructions by the control module is not specifically limited, which is prior art and will not be described again.

[0104] The computer program product of the present application can be a computer program implemented on one or more computers. The program itself can be stored on a computer-readable medium, such as a magnetic or optical drive, a memory, etc. The computer-readable medium is a tangible computer-readable storage medium that can contain, and / or store data or instructions for conduction one or more computer processes. The computer-readable medium can be a machine-readable storage device, a machine-readable storage medium, a machine-readable medium, a computer-readable storage device, a computer-readable storage medium, or a memory device. The computer-readable medium can include, but is not limited to, floppy diskettes, optical disks, CD-ROMs, DVDs, read-only memory (ROM), random access memory (RAM), erasable programmable memory (EPROM), electrically erasable programmable memory (EEPROM), magnetic or optical cards, flash memory, or any other form of storage for software. Of course, the computer-readable medium is not limited to physical and tangible forms of media, but can include transitory signals, such as signals traveling through the air, optical lines, wired lines, and wires. Accordingly, the computer program product of the present application can be embodied in various forms.

[0105] Obviously, the above-described embodiments of the present application are only examples for clearly illustrating the present application, and are not intended to limit the implementation manners of the present application. Based on the above description, any modifications, equivalent replacements, and improvements made by those skilled in the art without departing from the spirit and principle of the present application shall fall within the protection scope of the present application.

Claims

1. A self-balancing loss reduction and efficiency increasing system for photovoltaic module power generation, characterized in that, The application relates to a photovoltaic module, a balance module, an information acquisition module, a control module and an output module. The photovoltaic module comprises a plurality of photovoltaic components connected in series to form a complete closed photovoltaic circuit. The balance module is connected to the photovoltaic module to adjust the working parameters of the photovoltaic components, store the excess power generated by the photovoltaic components and output the excess power to the photovoltaic components needing compensation. The information acquisition module is connected to the photovoltaic module and the balance module to detect the working parameters of the photovoltaic components, acquire the power storage amount of the excess power in the balance module, detect the power output parameters and output time of the balance module and determine the photovoltaic components needing compensation according to the working parameters of the photovoltaic components. The control module is connected to the balance module and the information acquisition module to determine whether the photovoltaic components need power compensation according to the working parameters of the non-compensation photovoltaic components, determine whether all the photovoltaic components need output efficiency compensation according to the power storage amount, determine the efficiency compensation mode according to the power output parameters and output time and send control instructions to the balance module. The output module is connected to the photovoltaic module, the balance module and the information acquisition module to output final power. The control module determines the efficiency compensation mode according to the power output parameters and output time, which comprises the following steps. The control module performs first power efficiency compensation on the photovoltaic components with the maximum output current. If there is residual power storage, the residual power storage is equally compensated to all the photovoltaic components for second power efficiency compensation. If there is no residual power storage, the duration of the first power efficiency compensation is determined according to the output time of the compensation to the photovoltaic components needing compensation. The power output parameters comprise the current value of the secondary compensation photovoltaic components and the output time comprises the start time and end time of the total compensation current value of the secondary compensation photovoltaic components. The duration of the first power efficiency compensation is determined according to the output time of the compensation to the photovoltaic components needing compensation, which is the duration of the compensation current of the photovoltaic components needing compensation under the same illumination condition according to historical data.

2. The self-balancing loss reduction and efficiency increasing system for photovoltaic module power generation connection according to claim 1, characterized in that, The balance module comprises an input power interface connected to the photovoltaic components in the photovoltaic module, an amplification circuit unit connected to the input power interface to process the excess power and obtain compensation power, a lithium ion capacitor pre-storage unit connected to the amplification circuit unit to store the excess power generated by the photovoltaic components and a lithium ion capacitor output unit connected to the lithium ion capacitor pre-storage unit and the photovoltaic components to output the compensation power to the photovoltaic components needing compensation. The power output parameters detected by the information acquisition module comprise the compensation target photovoltaic components and the compensation current value of the compensation target photovoltaic components. The output time detected by the information acquisition module comprises the start time and end time of the total compensation current value of each compensation target photovoltaic component. The information acquisition module determines the photovoltaic components needing compensation according to the working parameters of the photovoltaic components, which comprises the following steps. ​ 3. The self-balancing loss reduction and efficiency increasing system for photovoltaic module power generation connection according to claim 2, characterized in that, ​ ​ 4. The system for self-balancing loss reduction and efficiency improvement of photovoltaic module power generation connection according to claim 3, characterized in that, ​ If the difference between the output current of the current photovoltaic module and the output current of any other photovoltaic module is greater than the individual compensation threshold, the current photovoltaic module is the photovoltaic module that needs compensation.

5. The self-balancing loss reduction and efficiency improvement system for photovoltaic module power generation connection according to claim 4, characterized in that, The control module determines the power generation fluctuation characteristic parameter according to the operating parameters of the non-compensated photovoltaic modules. The control module calculates the average value of the output currents of all non-compensated photovoltaic modules and the average deviation of the output currents of all non-compensated photovoltaic modules, and determines the power generation fluctuation characteristic parameter according to the average deviation and the average value.

6. The self-balancing loss reduction and productivity increasing system for photovoltaic module power generation connection according to claim 5, characterized in that, The control module determines whether the remaining photovoltaic modules need to be compensated for electric energy according to the power generation fluctuation characteristic parameter, If the power generation fluctuation characteristic parameter is greater than the standard fluctuation characteristic parameter, the control module determines that the remaining photovoltaic modules need to be compensated for electric energy. If the power generation fluctuation characteristic parameter is less than or equal to the standard fluctuation characteristic parameter, the control module determines that the remaining photovoltaic modules do not need to be compensated for electric energy.

7. The self-balancing loss reduction and productivity increasing system for photovoltaic module power generation connection according to claim 6, characterized in that, The control module is configured to determine whether to increase the output of all photovoltaic modules in response to the determination that the remaining photovoltaic modules do not need to be compensated for electric energy and in combination with the amount of stored electric energy, and specifically includes: If the amount of stored electric energy is greater than the electric energy demand of the photovoltaic module that needs compensation, the control module determines to increase the output of all photovoltaic modules. If the amount of stored electric energy is less than or equal to the electric energy demand of the photovoltaic module that needs compensation, the control module determines not to increase the output of all photovoltaic modules.

8. The system for self-balancing loss reduction and efficiency improvement of photovoltaic module power generation connection according to claim 7, characterized in that, The control instructions sent by the control module to the balancing module include photovoltaic module compensation instructions, first electric energy compensation instructions, and second electric energy compensation instructions. Each compensation instruction includes the amount of electric energy compensation for each photovoltaic module.

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