Component-level voltage balancing method and device for photovoltaic system

Abstract

The invention relates to the technical field of data processing, and discloses a component-level voltage balancing method and device of a photovoltaic system. The method comprises the following steps: performing multi-channel synchronous voltage data acquisition on each photovoltaic module in a photovoltaic string to obtain a string voltage data set; performing voltage deviation calculation and analysis on the string voltage data set to obtain a voltage diagnosis result; performing equalization target calculation on the voltage diagnosis result to obtain a target voltage parameter; performing MPPT controller configuration on the target voltage parameter to obtain a control parameter scheme; performing power optimization control according to the control parameter scheme to obtain voltage regulation data; and carrying out comparative analysis on the voltage regulation data and the string voltage data set to obtain an equalization effect result. According to the invention, the efficiency and accuracy of component-level voltage balancing of the photovoltaic system are improved.

Description

Technical Field

[0001] This application relates to the field of data processing, and particularly to a component-level voltage equalization method and device for a photovoltaic system. Background Art

[0002] In the field of photovoltaic energy, voltage equalization of a photovoltaic system is one of the key factors to ensure the efficient and stable operation of the system. Traditional methods for voltage equalization of a photovoltaic system mainly achieve it through centralized voltage regulation devices, such as using DC / DC converters or centralized inverters to adjust the voltage level of the entire photovoltaic string. However, with the continuous development of photovoltaic technology, the diversity and complexity of photovoltaic components have increased day by day, and the centralized voltage regulation method has gradually exposed disadvantages such as slow response speed, low regulation accuracy, and large energy loss. Therefore, the component-level voltage equalization technology has emerged. It installs independent voltage regulation modules on each component of the photovoltaic string to achieve precise control and regulation of the voltage of each component, thereby improving the overall efficiency and stability of the photovoltaic system.

[0003] Although the component-level voltage equalization technology has significant advantages in improving the efficiency of the photovoltaic system, the existing component-level voltage equalization methods still have some deficiencies. First, the existing voltage data acquisition and processing technologies often cannot achieve multi-channel synchronous acquisition, resulting in the accuracy and timeliness of voltage data being affected. Second, the calculation and analysis methods of voltage deviation are relatively simple and cannot fully reflect the voltage characteristics of photovoltaic components, thus limiting the accuracy and effect of voltage equalization. In addition, most of the existing MPPT controller configurations and power optimization control strategies are based on empirical formulas and fixed parameters, lacking adaptability and flexibility, and it is difficult to cope with complex and changeable lighting and environmental conditions. Finally, the evaluation methods of voltage equalization effects usually only focus on the improvement of voltage and ignore the changes in system power and efficiency, resulting in incomplete and inaccurate evaluation results. Summary of the Invention

[0004] This application provides a component-level voltage equalization method and device for a photovoltaic system, which are used to improve the efficiency and accuracy of component-level voltage equalization of the photovoltaic system.

[0005] In a first aspect, the present application provides a method for component-level voltage equalization of a photovoltaic system. The method for component-level voltage equalization of the photovoltaic system includes: performing multi-channel synchronous voltage data acquisition on each photovoltaic component in a photovoltaic string to obtain a string voltage data set; calculating and analyzing voltage deviations of the string voltage data set to obtain a voltage diagnosis result; calculating an equalization target based on the voltage diagnosis result to obtain target voltage parameters; configuring an MPPT controller with the target voltage parameters to obtain a control parameter scheme; performing power optimization control according to the control parameter scheme to obtain voltage regulation data; and comparing and analyzing the voltage regulation data with the string voltage data set to obtain an equalization effect result.

[0006] In a second aspect, the present application provides a device for component-level voltage equalization of a photovoltaic system. The device for component-level voltage equalization of the photovoltaic system includes:

[0007] An acquisition module, configured to perform multi-channel synchronous voltage data acquisition on each photovoltaic component in a photovoltaic string to obtain a string voltage data set;

[0008] A calculation module, configured to calculate and analyze voltage deviations of the string voltage data set to obtain a voltage diagnosis result;

[0009] An equalization module, configured to calculate an equalization target based on the voltage diagnosis result to obtain target voltage parameters;

[0010] A configuration module, configured to configure an MPPT controller with the target voltage parameters to obtain a control parameter scheme;

[0011] A control module, configured to perform power optimization control according to the control parameter scheme to obtain voltage regulation data;

[0012] A comparison module, configured to compare and analyze the voltage regulation data with the string voltage data set to obtain an equalization effect result.

[0013] In the technical solution provided by this application, through multi-channel synchronous voltage data acquisition, the accuracy and timeliness of the voltage data of each photovoltaic module in the photovoltaic string are ensured, providing a solid foundation for subsequent analysis and processing. This high-precision data acquisition method can more comprehensively reflect the actual voltage state of the photovoltaic modules compared with traditional manual or decentralized acquisition, avoiding misjudgment and improper adjustment caused by data errors. By calculating and analyzing the voltage deviation of the string voltage data set, not only the voltage diagnosis result is obtained, but also the problem of voltage imbalance can be discovered and solved in a timely manner. This process not only considers the average value of the voltage, but also conducts a detailed analysis of the voltage deviation through standard deviation and threshold classification processing, thereby ensuring the accuracy and pertinence of voltage balance. This comprehensive and in-depth analysis method helps the operation and maintenance personnel accurately judge the operation state of the photovoltaic modules, take measures in a timely manner, and avoid potential safety hazards. Next, through the balance target calculation, the target voltage parameters are obtained, and the MPPT controller is configured accordingly to achieve precise adjustment of the voltage of the photovoltaic modules. This process not only considers the voltage value at the maximum power point, but also combines the priority and adjustable range of the components with over-limit deviation to ensure the rationality and effectiveness of voltage adjustment. This adaptive controller configuration method can flexibly adjust the voltage level of the photovoltaic modules according to different illumination and environmental conditions, improving the response speed and adjustment accuracy of the system. Through the comparison and analysis of the power optimization control and voltage adjustment data, the balance effect result is obtained. This process not only focuses on the improvement of the voltage, but also comprehensively evaluates the impact of voltage balance on the system power and efficiency through methods such as standardization processing, deviation calculation, statistical analysis of power change values, and evaluation of efficiency parameters. Description of the Drawings

[0014] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0015] Figure 1 It is a schematic diagram of an embodiment of the component-level voltage balance method of the photovoltaic system in the embodiment of this application;

[0016] Figure 2 It is a schematic diagram of an embodiment of the component-level voltage balance device of the photovoltaic system in the embodiment of this application. Detailed Embodiments

[0017] The embodiments of the present application provide a method and device for component-level voltage equalization of a photovoltaic system. Terms such as "first", "second", "third", "fourth", etc. (if any) in the specification, claims and the above-mentioned drawings of the present application are used to distinguish similar objects and do not necessarily need to describe a specific order or sequence. It should be understood that such data used can be interchanged under appropriate circumstances so that the embodiments described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "comprising" or "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0018] For ease of understanding, the specific process of the embodiments of the present application will be described below. Please refer to Figure 1 , an embodiment of the component-level voltage equalization method of the photovoltaic system in the embodiments of the present application includes:

[0019] Step S101: Perform multi-channel synchronous voltage data acquisition on each photovoltaic component in the photovoltaic string to obtain a string voltage data set;

[0020] Step S102: Calculate and analyze the voltage deviation of the string voltage data set to obtain a voltage diagnosis result;

[0021] Step S103: Calculate the equalization target for the voltage diagnosis result to obtain target voltage parameters;

[0022] Step S104: Configure the MPPT controller for the target voltage parameters to obtain a control parameter scheme;

[0023] Step S105: Perform power optimization control according to the control parameter scheme to obtain voltage regulation data;

[0024] Step S106: Compare and analyze the voltage regulation data with the string voltage data set to obtain an equalization effect result.

[0025] It can be understood that the execution entity of the present application can be a component-level voltage equalization device of a photovoltaic system, or a terminal or a server, and specific details are not limited herein. The embodiments of the present application will be described by taking the server as the execution entity as an example.

[0026] Specifically, first, multi-channel synchronous voltage data acquisition is performed on each photovoltaic module in the photovoltaic string to obtain a string voltage data set. This process involves real-time voltage sampling and data transmission of multiple photovoltaic modules, and ensures that the data acquisition of each module is carried out at the same moment to maintain the time synchronization of the data. Specifically, by setting the synchronous clock signals for the master station and slave stations, time synchronization processing is performed using the IEEE1588 time synchronization protocol to ensure that all slave stations perform voltage acquisition under a consistent time reference. The synchronous acquisition command is transmitted through the POWERBUS bus, and each slave station responds to the acquisition command and completes the sampling to obtain the voltage sampling values of the modules. Subsequently, data transmission and aggregation are carried out through the POWERBUS bus, and finally a complete string voltage data set is obtained. After the acquisition is completed, it enters the stage of voltage deviation calculation and analysis. In this stage, the string voltage data set is first analyzed, and the reference voltage is obtained by calculating the average value of the voltage values of all modules. The reference voltage is a reference value of the voltage in the entire string, which is used to judge the voltage differences between the modules. Next, the deviation between each module and it is calculated through the reference voltage to obtain the voltage deviation data. The voltage deviation data is used to measure the voltage fluctuation of each module relative to the overall system, which is crucial for the implementation of subsequent balancing control. The deviation data can not only quantify the difference between the voltage of each module and the reference voltage, but also further statistically analyze the deviation through methods such as standard deviation, so as to have a more comprehensive understanding of the overall distribution of the deviation. During the analysis process, threshold classification processing is performed on the voltage deviation data, and the modules are divided into multiple categories, such as "normal deviation", "mild deviation", and "severe deviation", etc. In this way, through classification, the health status of each module can be better judged, providing a basis for subsequent balancing operations. Finally, the classification results of the modules are comprehensively considered with the statistical parameters to form a voltage diagnosis result, which clarifies the status of each module and its deviation degree from the reference voltage.

[0027] After the voltage diagnosis result is formed, it enters the stage of calculating the balancing target. The purpose of calculating the balancing target is to determine how to adjust the voltages of each component to make them as balanced as possible, thereby improving the overall performance of the photovoltaic string. First, the maximum power point voltage is determined through the voltage diagnosis result to obtain the reference voltage value. The maximum power point voltage represents the optimal power output state that the component can achieve, and this reference value is used as the target for subsequent voltage regulation. Next, the components with deviations exceeding the set limit are prioritized to determine the order of adjustment. The basis for this prioritization is usually the magnitude of the voltage deviation, and the components with larger deviations have higher priorities. According to the reference voltage value, the voltage value that each component needs to increase or decrease is calculated to achieve the balancing effect. The calculation of the adjustment amount needs to be verified in combination with the safety range to ensure that the adjustment amount is within the allowable range of the component and avoid damaging the component due to excessive voltage adjustment. Finally, according to the adjustment priority and the adjustable range, the parameters of all components are integrated to obtain the final target voltage parameters, which are used to guide the subsequent control operations. Subsequently, it enters the configuration of the MPPT controller for the target voltage parameters to obtain the control parameter scheme. The MPPT controller is a device used to find the maximum power output point. By configuring the MPPT controller, the dynamic adjustment of the output voltage and current of the photovoltaic module can be achieved, thereby achieving the purpose of balancing the voltage and improving the overall efficiency of the system. First, the frequency of the LLC resonant circuit is set for the target voltage parameters to obtain the appropriate operating frequency range to ensure that the system operates within the optimal voltage range. Then, the initial duty cycle of PWM (pulse width modulation) is calculated to obtain the parameters for modulation. The setting of the duty cycle directly affects the adjustment effect of the output voltage, so it needs to be calculated very precisely. At the same time, the response parameters of the controller also need to be set to ensure that the controller can respond quickly and accurately when adjusting the voltage. In addition, the stability of the dynamic characteristic parameters is verified to ensure the stability of the system during the adjustment process and avoid oscillation or overshoot phenomena. Through the calibration of these parameters, the control parameter scheme is finally formed to guide the subsequent voltage adjustment process.

[0028] After obtaining the control parameter scheme, power optimization control is carried out to achieve the balanced control of the photovoltaic module voltage and obtain the voltage regulation data. The purpose of power optimization control is to make the photovoltaic modules operate near the maximum power point by adjusting their working states. First, three-point comparison sampling is performed according to the control parameter scheme, that is, the target voltage is adjusted slightly up and down to obtain three different power values, and the maximum power value is determined from them, which is the current optimal point. After finding the optimal point, the PWM duty cycle is adjusted according to this optimal point to make the voltage of the module gradually tend to the optimal state. The power optimization control transmits the control signal through the PLC (Programmable Logic Controller) carrier, transmits the signal to the specific photovoltaic module control module, and finally executes the voltage regulation operation to obtain the adjusted voltage data. The last step is to compare and analyze the voltage regulation data with the initial string voltage data set to evaluate the effect of voltage balance. First, the voltage regulation data is standardized for comparison with the original voltage data. The deviation calculation is performed through the standardized data and the string voltage data set to obtain the voltage improvement index. The improvement index can quantify the voltage balance effect after regulation and show how the voltage consistency of each component has been improved through voltage regulation. After calculating the improvement index, the string power is recalculated according to the improved voltage data to obtain the power change value, so as to evaluate the improvement effect of the overall system power. Further, statistical analysis is performed on the power change value to obtain the efficiency parameters of the entire photovoltaic string. Finally, combining the efficiency parameters and the improvement index, a comprehensive analysis of the balance effect is carried out to form a final balance effect report.

[0029] For example, assume that a photovoltaic string contains 10 photovoltaic modules. The string voltage data set obtained by synchronous acquisition shows that the voltage deviations of three modules are significantly beyond the reference voltage, being 0.5V higher, 0.6V higher, and 0.7V lower respectively. Through priority sorting, these three modules are listed as the targets for priority regulation. For the modules with higher voltage, the output voltage is reduced to near the reference voltage by adjusting the PWM duty cycle, while for the modules with lower voltage, the output voltage is increased to near the reference voltage by increasing the duty cycle. After the balance adjustment, the voltages of all modules are collected and calculated again, and it is found that the deviations are all reduced to within 0.1V, and the overall system power output has increased by 5%. This data shows that through this voltage balance method, the output consistency of the photovoltaic modules has been significantly improved, and the power output efficiency of the entire system has also been effectively improved.

[0030] In the embodiments of the present application, through multi-channel synchronous voltage data acquisition, the accuracy and timeliness of the voltage data of each photovoltaic module in the photovoltaic string are ensured, providing a solid foundation for subsequent analysis and processing. This high-precision data acquisition method can more comprehensively reflect the actual voltage state of the photovoltaic modules compared with traditional manual or decentralized acquisition, avoiding misjudgment and improper adjustment caused by data errors. By calculating and analyzing the voltage deviation of the string voltage data set, not only the voltage diagnosis result is obtained, but also the problem of voltage imbalance can be discovered and solved in time. This process not only considers the average value of the voltage, but also conducts a detailed analysis of the voltage deviation through standard deviation and threshold classification processing, thus ensuring the accuracy and pertinence of voltage balance. This comprehensive and in-depth analysis method helps the operation and maintenance personnel accurately judge the operation state of the photovoltaic modules, take measures in time, and avoid potential safety hazards. Next, through the balance target calculation, the target voltage parameters are obtained, and the MPPT controller is configured accordingly to achieve precise adjustment of the voltage of the photovoltaic modules. This process not only considers the voltage value at the maximum power point, but also combines the priority and adjustable range of the components with deviation exceeding the limit, ensuring the rationality and effectiveness of voltage adjustment. This adaptive controller configuration method can flexibly adjust the voltage level of the photovoltaic modules according to different lighting and environmental conditions, improving the response speed and adjustment accuracy of the system. Through the comparison and analysis of the power optimization control and voltage regulation data, the balance effect result is obtained. This process not only focuses on the improvement of the voltage, but also comprehensively evaluates the impact of voltage balance on the system power and efficiency through methods such as standardization processing, deviation calculation, power change value statistical analysis, and efficiency parameter evaluation.

[0031] In a specific embodiment, the process of executing step S101 may specifically include the following steps:

[0032] (1) Perform clock synchronization settings on the master station and slave stations in the photovoltaic string to obtain a synchronous clock signal;

[0033] (2) Perform IEEE1588 time synchronization processing on the synchronous clock signal to obtain the acquisition time reference for each slave station;

[0034] (3) Send a synchronous acquisition command to each slave station according to the acquisition time reference to obtain the component voltage sampling value;

[0035] (4) Perform POWERBUS bus transmission processing on the component voltage sampling value to obtain voltage transmission data;

[0036] (5) Perform summarization and formatting processing on the voltage transmission data to obtain a string voltage data set.

[0037] Specifically, it is necessary to complete the clock synchronization setting between the master station and slave stations in the PV string to ensure that the data acquisition of each PV module can be synchronously executed under a unified time reference, thereby improving the reliability and comparability of data. Clock synchronization is the basis for realizing multi-channel synchronous acquisition. The master station establishes a time synchronization relationship with the slave stations by broadcasting synchronization signals to generate synchronous clock signals. In this way, it is ensured that the data acquisition of each component in the entire PV string can be carried out strictly according to the same time reference. After the clock synchronization setting is completed, the next step is to perform IEEE 1588 time synchronization processing on the synchronous clock signal to further improve the accuracy of time synchronization. IEEE 1588 is a precision clock synchronization protocol widely used in scenarios that require high-precision time synchronization. By using the IEEE 1588 time synchronization protocol, a high-precision time reference can be established between the master station and slave stations to ensure the time consistency of data acquisition for each slave station, thus avoiding errors caused by time asynchronization. Through this time synchronization processing, the data acquisition time reference of each slave station can be obtained, ensuring that the voltage data of all components are acquired at the same time node.

[0038] After obtaining the unified acquisition time reference, the master station sends synchronous acquisition commands to each slave station. The role of the synchronous acquisition command is to trigger each slave station to execute the voltage data acquisition operation at a unified time point to obtain the voltage sampling value of each PV module. In this way, it is ensured that the acquisition behaviors of all slave stations occur simultaneously, which is particularly important for subsequent voltage balance analysis and processing because the voltages of different components must be acquired under the same conditions to perform effective comparative analysis and balance adjustment. After the voltage sampling value is obtained, it needs to be transmitted and processed through the POWERBUS bus to form unified voltage transmission data. In this process, the acquired voltage data is sent from each slave station to the master station. The POWERBUS bus, as the data transmission channel, ensures the integrity and real-time nature of the data during transmission with its high-speed and stable characteristics. After all the data from the slave stations is transmitted to the master station through the bus, the master station will receive and summarize these data to form a complete string voltage data set.

[0039] Finally, the transmitted voltage data is summarized and formatted to obtain the string voltage data set. The voltage data set is the basis for subsequent voltage deviation calculation and analysis. Therefore, the data is structured to facilitate subsequent analysis and calculation. The summarization process includes uniformly organizing the voltage data of each component, removing noise and errors, and storing and organizing it in a predefined format. After formatting, the string voltage data set has data integrity and consistency, providing accurate input data for subsequent voltage deviation analysis and balancing control. This series of steps constitutes the complete process of multi-channel synchronous voltage acquisition in a photovoltaic string. Through clock synchronization between the master station and slave stations, precise time control of the IEEE 1588 time synchronization protocol, triggering of synchronous acquisition commands, POWERBUS bus transmission of data, and summarization and formatting of voltage data, a string voltage data set for voltage balance analysis is finally formed. This precise acquisition method makes the voltage data highly accurate and synchronous, laying a solid foundation for the subsequent voltage balance process.

[0040] For example, in practical applications, assume a photovoltaic string contains 20 photovoltaic components. The master station first sets clock synchronization with the 20 slave stations and ensures the same time reference for each slave station through the IEEE 1588 protocol. Under the control of the synchronized time reference, the master station sends acquisition commands to all slave stations simultaneously. Each slave station collects its respective voltage data at the same time node. For example, the voltages of the 20 components are 35.1V, 34.9V, 35.0V, etc. Subsequently, the collected voltage data is transmitted to the master station through the POWERBUS bus, and the master station summarizes and formats this data to form a unified voltage data set. Through this voltage data set, it can be found that there are slight differences between the voltages of each component, and these differences are the basis for subsequent balancing adjustments, thereby improving the performance and efficiency of the entire photovoltaic string.

[0041] In a specific embodiment, the process of performing step S102 may specifically include the following steps:

[0042] (1) Calculate the average value of the string voltage data set to obtain the reference voltage value;

[0043] (2) Calculate the difference between the voltage of each component in the string voltage data set and the reference voltage value to obtain the voltage deviation data;

[0044] (3) Calculate the standard deviation of the voltage deviation data to obtain the deviation statistical parameter;

[0045] (4) Perform threshold classification processing on the voltage deviation data to obtain the component classification result;

[0046] (5)Comprehensively process the component classification results and deviation statistical parameters to obtain the voltage diagnosis result.

[0047] Specifically, calculate the average value of the string voltage dataset to obtain the reference voltage value. The reference voltage is a very important reference quantity, which represents the average voltage level of the entire string. By averaging the voltage data of all components, the reference voltage can be obtained as the standard value for subsequent analysis and balancing control. The average value calculation is the basis of voltage deviation analysis, which is used to measure the deviation degree of each component voltage relative to the overall voltage level. Next, based on the calculated reference voltage, calculate the difference between the voltage value of each component in the string voltage dataset and the reference voltage to obtain the voltage deviation data. The voltage deviation data is used to quantify the gap between the voltage of each component and the reference voltage. This gap can be used to analyze whether the performance of the components in the string is balanced. The component with a smaller deviation means its working state is closer to the ideal state, while the component with a larger deviation needs to be adjusted through balancing operations. Through this calculation, voltage anomalies in the system can be identified, and the components with larger deviations can be found, providing a basis for subsequent balancing processing.

[0048] After obtaining the voltage deviation data, calculate the standard deviation to obtain the deviation statistical parameter. The standard deviation is an important statistical index used to measure the dispersion degree of data distribution. By calculating the standard deviation of the voltage deviation, the difference degree between the component voltages can be evaluated. If the standard deviation is small, it means that the component voltages are relatively concentrated and the overall consistency is good; while if the standard deviation is large, it indicates that the voltage differences between the components are large and the voltage balance of the system is poor, and further adjustment operations are needed. Therefore, the standard deviation calculation result provides a quantitative basis for the subsequent determination of the balancing target and control strategy. After the voltage deviation data calculation is completed, perform threshold grading processing on it to obtain the classification result of the components. The purpose of threshold grading processing is to classify the components into different categories according to the size of the voltage deviation. For example, two thresholds can be set to distinguish three categories: "normal deviation", "slight deviation", and "severe deviation". The components with deviations within the first threshold can be classified as "normal", those between the second threshold and the first threshold as "slight deviation", and those exceeding the second threshold as "severe deviation". By classifying the components in this way, it can be more clearly identified which components' voltage levels need to be adjusted first to effectively improve the voltage consistency of the entire system.

[0049] Finally, the classification results of the components and the deviation statistical parameters are comprehensively processed to obtain the voltage diagnosis result. The voltage diagnosis result is a comprehensive summary of the voltage deviations of each component in the entire system, including the status of each component and its deviation from the reference voltage. The comprehensive processing process takes into account the classification of each component and the relationship between its deviation value and the standard deviation, in order to more comprehensively analyze the balance status of the system. Through this comprehensive analysis, the diagnosis status of each component can be obtained, such as whether it is in a normal state, requires minor adjustment or requires key adjustment. The voltage diagnosis result provides a direct basis for subsequent balance target setting and control operations, and is a key step in achieving component-level voltage balance control.

[0050] For example, in a string containing 15 photovoltaic components, first, the voltages of all components are collected. Assuming the voltage data of each component are 34.8V, 35.2V, 34.9V, etc. Calculate the average value of these data to obtain the reference voltage of 35.0V. Then, calculate the difference between each component and the reference voltage. For example, the difference between the first component and the reference voltage is -0.2V, the difference of the second component is +0.2V, the third component is -0.1V, etc. Next, calculate the standard deviation of these deviation data. Assuming the result is 0.15V, which means the deviation degree of the component voltages is not large. Perform threshold classification processing on these deviation data, set ±0.1V as the normal threshold, ±0.2V as the minor deviation threshold, and more than ±0.2V as the severe deviation. In this way, the components with deviations within ±0.1V are classified as normal, the components with deviations between ±0.1V and ±0.2V are classified as minor deviations, and the components exceeding ±0.2V are classified as severe deviations. Finally, combine these classification results with the deviation statistical parameters to obtain the voltage diagnosis result, which shows which components need to be adjusted preferentially and which components are in a normal state, thus providing clear adjustment targets and bases for subsequent balance operations.

[0051] In a specific embodiment, the process of executing step S103 may specifically include the following steps:

[0052] (1) Determine the maximum power point voltage for the voltage diagnosis result to obtain the reference voltage value;

[0053] (2) Sort the components with excessive deviations in the voltage diagnosis result to obtain the adjustment sequence;

[0054] (3) Calculate the voltage increase and decrease amounts for each component according to the reference voltage value to obtain the adjustment amount data;

[0055] (4) Verify the safety range of the adjustment amount data to obtain the adjustable range;

[0056] (5) Integrate parameters according to the adjustment sequence and adjustable range to obtain the target voltage parameter.

[0057] Specifically, determine the voltage at the maximum power point (MPP) from the voltage diagnosis results to obtain the reference voltage value. The maximum power point is an important characteristic point of the photovoltaic system. At this point, the output power of the photovoltaic module is the highest, and the maximum electrical energy conversion efficiency can be achieved. To determine the reference voltage value, it is necessary to comprehensively consider the voltage diagnosis results of all components to find the voltage value that can make the entire string reach the maximum power output. The reference voltage value will be used as the target value for subsequent voltage equalization adjustment, so that each component tends to this reference voltage as much as possible, thereby maximizing the power output of the entire string.

[0058] After obtaining the reference voltage value, prioritize the components with out-of-limit deviations in the voltage diagnosis results to obtain the adjustment sequence. Components with out-of-limit deviations refer to those components whose voltages deviate significantly from the reference voltage, usually indicating that the output power of these components is far from the maximum power point. Therefore, voltage adjustment is required first. The basis for priority sorting is usually the absolute value of the voltage deviation. The greater the deviation, the higher the priority of the component, which means it needs to be adjusted first. Adjusting the component with the largest deviation first during the adjustment process helps to quickly improve the overall efficiency of the system. The finally obtained adjustment sequence provides the basis for the specific order of subsequent voltage adjustment. Then, calculate the voltage increase or decrease amount for each component based on the reference voltage value to obtain the adjustment amount data for each component. The adjustment amount data quantifies the voltage adjustment amplitude of the component and is used to determine the voltage value that each component needs to increase or decrease to reach the balanced target state. When calculating the adjustment amount, it is necessary to consider the gap between the current voltage value of each component and the reference voltage value to determine the direction and amplitude of the adjustment. For components with large deviations, the adjustment amount will also increase accordingly to speed up the adjustment process, while for components with small deviations, the adjustment amount can be relatively small to maintain the stability of the system.

[0059] The calculated adjustment amount data needs to be verified within the safety range to obtain the adjustable range. Verifying the safety range is an important step to ensure that the voltage adjustment of each component does not exceed its physically allowed range, thus avoiding damage to the component caused by excessive adjustment. During the verification process, it is necessary to consider the operating voltage range of the photovoltaic module and the overall safety requirements of the system to ensure that the adjustment amount is within the allowable range of the component. If the adjustment amount exceeds the safety range, appropriate corrections need to be made to ensure that the voltage adjustment of each component is within a reasonable range. After verification, the adjustable voltage ranges are obtained, and these ranges define the maximum amplitude by which each component can adjust its voltage.

[0060] Finally, the adjustment parameters of each component are integrated according to the adjustment sequence and adjustable range to obtain the target voltage parameters. The target voltage parameters are the result of comprehensive consideration of the adjustment plans of each component of the entire system, combining the adjustment priority and adjustable range to achieve the balance of the overall system. During the integration process, it is necessary to integrate the priority, adjustment amount and safety interval of each component to develop a complete voltage adjustment plan to ensure that all components can approach the reference voltage as much as possible, thereby achieving the maximum power output state of the system.

[0061] For example, suppose a photovoltaic string contains 10 components. The voltage diagnosis results show that the voltage deviation of three components exceeds the set threshold: the voltage deviation of component A is +0.8V, the voltage deviation of component B is -1.0V, and the voltage deviation of component C is +1.2V. First, by analyzing the voltage output characteristics of the system, the reference voltage of the maximum power point is determined to be 35.0V. Next, the three components with excessive deviations are prioritized. The results show that component C has the largest deviation, so it has the highest priority, followed by component B and component A. According to the reference voltage value of 35.0V, the voltage increase or decrease of each component is calculated. For example, component A needs to decrease by 0.8V, component B needs to increase by 1.0V, and component C needs to decrease by 1.2V. After determining the adjustment amount, these adjustment amounts are verified for the safety range. Assuming that the maximum allowable adjustment range of the component is ±1.0V, then for component C, the adjustment amount of 1.2V exceeds the safety range, so the adjustment amount needs to be limited to 1.0V. After verification, the final adjustable range is 0.8V reduction for component A, 1.0V increase for component B, and 1.0V reduction for component C. Finally, according to the adjustment sequence and adjustable range, the voltage parameters of each component are integrated to obtain the target voltage parameters and form the final voltage adjustment scheme. Through this adjustment scheme, the voltage of each component tends to the reference voltage, thereby improving the power output and system efficiency of the entire string.

[0062] In a specific embodiment, the process of executing step S104 may specifically include the following steps:

[0063] (1) Setting the LLC resonant circuit frequency based on the target voltage parameter to obtain the operating frequency range;

[0064] (2) Calculate the initial value of the PWM duty cycle of the target voltage parameter to obtain the modulation parameter;

[0065] (3) Setting controller response parameters according to the operating frequency range to obtain dynamic characteristic parameters;

[0066] (4) Perform stability check on dynamic characteristic parameters to obtain correction coefficients;

[0067] (5) Calibrate the modulation parameters according to the correction factor to obtain the control parameter scheme.

[0068] Specifically, set the frequency of the LLC resonant circuit for the target voltage parameter to obtain the operating frequency range. The LLC resonant circuit is an efficient converter structure that utilizes the resonance principle to achieve efficient power transmission and voltage conversion. According to the target voltage parameter, determine the most suitable operating frequency range of the LLC resonant circuit. The purpose is to ensure that the system operates under optimal conditions, maximizing the conversion efficiency and power output. The setting of the operating frequency range must consider the amplitude of the target voltage and the resonance characteristics of the resonant circuit to ensure that the entire resonant system operates within the designed operating region, avoiding problems such as overload or reduced efficiency. Calculate the initial value of the PWM duty cycle for the target voltage parameter to obtain the modulation parameters for control and adjustment. The PWM duty cycle is used to control the voltage output. By changing the duty cycle, the output voltage of the circuit can be adjusted, thereby achieving the regulation of the component voltage. The calculation of the initial duty cycle value needs to be determined according to the target voltage and the current operating frequency range. By controlling the duty cycle of the PWM signal, the output voltage can be made close to the target voltage. The determination of the modulation parameters directly affects the change of the output voltage, and the accuracy of the initial value is crucial for the stability and rapidity of the adjustment process.

[0069] After obtaining the preliminary operating frequency range and modulation parameters, set the controller response parameters according to the operating frequency range to obtain the dynamic characteristic parameters. The controller response parameters are the key parameters used to adjust the response speed and performance of the controller. The operating frequency range has a direct impact on the dynamic characteristics of the controller. Therefore, it is necessary to set appropriate controller response parameters according to the frequency range to ensure that during the adjustment process of the resonant circuit and PWM control, the controller can quickly and smoothly respond to the voltage change. The dynamic characteristic parameters include the gain of the control system, response time, etc. Through reasonable setting, it can be ensured that the controller has sufficient response speed and maintains the stability of the system during the voltage regulation process. Next, perform a stability check on the dynamic characteristic parameters to obtain the correction factor. The purpose of the stability check is to ensure that during the entire voltage regulation process, the system will not exhibit excessive oscillation or instability. Due to the non-linear characteristics of the LLC resonant circuit and PWM regulation, the system may exhibit a relatively high dynamic gain or a long response time at certain operating points, thus affecting the stability of the system. Through the stability check, the possible unstable factors in the system can be detected, and the corresponding correction factor can be calculated. The correction factor is used to correct the control parameters to ensure that in actual operation, the system can maintain stability within a large range, avoiding overshoot or undershoot.

[0070] Finally, calibrate the modulation parameters according to the obtained correction coefficient to obtain the final control parameter scheme. The control parameter scheme is the parameter obtained by integrating each link. Through the corrected modulation parameters, it is ensured that when the system performs voltage regulation, it can quickly reach the target voltage and maintain the smoothness and stability of the regulation process. The control parameter scheme will be used for the actual operation of the control system to achieve precise regulation of the voltage of each component, thereby achieving the voltage balance target of the entire photovoltaic string, ensuring that the system operates at the maximum power point, and improving the overall power generation efficiency. For example, in a system containing multiple photovoltaic components, after calculating the balance target in the previous steps, the target voltage is set to 33.5V. Next, through the analysis of the LLC resonant circuit, the operating frequency range is set to 100kHz to 150kHz. Then, corresponding to the target voltage, the PWM duty cycle is initially calculated to be 60%, which is the initial setting required for the modulation voltage to reach the target voltage. According to this operating frequency range, set the response parameters of the controller so that the system can quickly respond to voltage changes within the frequency range to obtain dynamic characteristic parameters. For example, the system gain is set to 2 and the response time is 50ms.

[0071] During the stability verification, it is found that the response speed of the system at some operating points is slow, which may cause a certain delay in the regulation process. Through stability analysis, the correction coefficient is obtained as 0.8, which is used to reduce the system gain to ensure that there is no excessive oscillation during the voltage regulation process. Finally, calibrate the PWM duty cycle and control parameters according to the correction coefficient to determine the final control parameter scheme. This scheme will be used for actual voltage regulation to ensure that the voltage of each component gradually approaches the target voltage of 33.5V, so that the entire system reaches the best working state and improves the overall output power of the photovoltaic string.

[0072] In a specific embodiment, the process of executing step S105 may specifically include the following steps:

[0073] (1) Perform three-point comparison sampling on the control parameter scheme to obtain power characteristic points;

[0074] (2) Determine the maximum value of the power characteristic points to obtain the current optimal point;

[0075] (3) Adjust the PWM duty cycle according to the current optimal point to obtain a control signal;

[0076] (4) Transmit the control signal through the PLC carrier to obtain an execution instruction;

[0077] (5) Perform voltage regulation processing according to the execution instruction to obtain voltage regulation data.

[0078] Specifically, three-point comparative sampling is performed on the control parameter scheme to obtain power characteristic points. Three-point comparative sampling is a common method for power optimization, which determines the power characteristics of the system by sampling at different voltage points. Here, the voltage of each component is adjusted by slightly increasing, maintaining, and decreasing respectively, so as to obtain three different voltage points, and the corresponding power output is measured at each voltage point. In this way, by sampling the power at different voltages, the power characteristic points of the component can be obtained. Each power characteristic point represents the power output under different adjustment conditions, which can help determine the optimal power output under which voltage state. Next, the maximum value determination is performed on the collected power characteristic points to obtain the current optimal point. By comparing the power values of these three sampling points, the maximum value is found, and the voltage point corresponding to the maximum power is the current optimal point. The optimal point represents the best power output state that the component can achieve under the current conditions. Through this method of comparison and determination, the maximum power point suitable for the current environmental conditions can be quickly found, providing a basis for subsequent voltage regulation.

[0079] After finding the current optimal point, the PWM duty cycle is adjusted based on this optimal point to obtain a control signal for control regulation. The adjustment of the PWM duty cycle is to regulate the voltage output of the component by changing the high and low time ratio of the pulse. According to the voltage value determined by the optimal point, the control system adjusts the PWM duty cycle accordingly, so that the output voltage of the component gradually approaches the voltage of the optimal point, thereby achieving the best power output. The generation of the control signal is directly determined by the setting of the PWM duty cycle, ensuring that the voltage output of the system remains in the optimal state. The generated control signal needs to be transmitted through the PLC (Programmable Logic Controller) carrier to transmit the control signal to the execution modules of each component. The PLC carrier is a commonly used signal transmission technology in industrial control systems. It transmits control signals through power lines and has the characteristics of strong real-time performance and high reliability. After the control signal is transmitted to the control modules of each component through the PLC carrier, each component will perform corresponding voltage regulation according to the received signal. Transmitting the control signal through the PLC carrier can not only reduce the need for independent wiring but also maintain high signal transmission reliability in a complex photovoltaic environment.

[0080] Finally, voltage regulation processing is performed on the photovoltaic modules according to the received execution instructions, thereby obtaining voltage regulation data. Each module adjusts its own voltage according to the control signal to reach the target voltage corresponding to the optimal point. The adjustment process may involve adjusting the operating parameters of the internal circuit, such as adjusting the inductance and capacitance values, changing the duty cycle of the PWM, etc., to precisely control the voltage output. Through this refined adjustment, the output voltage of each module gradually approaches the maximum power point voltage, thereby maximizing the power output of the entire photovoltaic string. After the adjustment is completed, the final voltage value and the corresponding power data are recorded as the voltage regulation data.

[0081] For example, assume that the current goal of a certain photovoltaic module is to find the optimal power output point. First, a three-point comparison sampling is performed on the control parameter scheme. Assume that the three power characteristic points collected are 35.1W, 36.4W, and 34.8W, corresponding to the cases where the voltage regulation is +0.5V, 0V, and -0.5V respectively. By comparing these three power characteristic points, it is found that 36.4W is the maximum value, which indicates that the power output of the module is optimal when the current voltage remains unchanged. Therefore, it is determined that the current optimal point is to keep the voltage unchanged. Next, according to this optimal point, the PWM duty cycle is adjusted to be consistent with the target voltage to obtain the control signal. The control signal is transmitted to the control module of the module through PLC carrier wave. After the module receives the control signal, it executes the instruction to keep the current voltage, thereby achieving the optimal power output state. The final voltage regulation data is recorded as the target voltage and the corresponding power output. Through this dynamic adjustment process, the module can continuously operate at the maximum power point, thereby improving the power generation efficiency of the entire photovoltaic system.

[0082] In a specific embodiment, the process of executing step S106 may specifically include the following steps:

[0083] (1) Standardize the voltage regulation data to obtain standardized data;

[0084] (2) Calculate the deviation based on the standardized data and the string voltage dataset to obtain an improvement index;

[0085] (3) Calculate the string power for the improvement index to obtain a power change value;

[0086] (4) Perform statistical analysis on the power change value to obtain an efficiency parameter;

[0087] (5) Conduct comprehensive analysis based on the efficiency parameter and the improvement index to obtain the balanced effect result.

[0088] Specifically, the voltage regulation data is standardized to obtain standardized data. The purpose of standardization is to transform the voltage data of different components to the same dimension, enabling them to be compared and calculated on the same basis. Since the voltage of photovoltaic modules may fluctuate within a certain range and there may be significant differences in the voltage values among components, standardization is required to eliminate such differences for subsequent calculations and analyses. Standardization usually involves subtracting the mean value corresponding to each component from its voltage value and then dividing by the standard deviation, which normalizes the data and makes them comparable. This step of standardization ensures that the voltage regulation effects of each component are evaluated on the same basis, thus better assessing the overall voltage balance effect. Deviation calculations are performed based on the standardized data and the string voltage dataset to obtain improvement indicators. The improvement indicators are used to measure whether the voltage consistency of each component has been improved after voltage regulation. By calculating the deviation between the standardized voltage data and the string voltage dataset before regulation, the voltage regulation effect of each component can be quantified. For example, the change in voltage deviation before and after regulation can be calculated, and the smaller the deviation, the better the balance effect. The improvement indicators are obtained by comparing the voltage deviations before and after regulation and can intuitively reflect the balance effect after regulation.

[0089] After obtaining the improvement indicators, the string power is further calculated based on them to obtain the power change value. The power change value is used to measure the impact of voltage regulation on the overall output power of the system. The output power of photovoltaic modules is closely related to voltage. By improving voltage consistency, the power output of the entire string can be increased. Therefore, the process of calculating the power change value is to compare the component powers before and after regulation and evaluate the specific effect of voltage regulation on power improvement. If the voltages of each component are closer to the optimal voltage point after regulation, higher power output can usually be achieved. The power change value can be the cumulative value of the powers of each component, thus reflecting the change in the overall power of the string. Next, statistical analysis is performed on the power change value to obtain efficiency parameters. The efficiency parameters are used to evaluate the overall working efficiency of the entire photovoltaic string after voltage regulation. During the statistical analysis process, parameters such as the average value, maximum value, and minimum value of the overall power change may be calculated to comprehensively evaluate the impact of voltage regulation on system efficiency. In addition, distribution analysis can also be performed on the power change of each component to understand which components' power outputs have been significantly improved and which components' outputs are still insufficient after voltage balance regulation. Through this process, the improvement of voltage regulation on the overall system efficiency can be quantitatively understood.

[0090] Finally, a comprehensive analysis is performed based on the efficiency parameter and improvement index to obtain the balanced effect result. The comprehensive analysis integrates all the data and parameters obtained previously to derive the final evaluation of the balanced effect. The comprehensive analysis considers various aspects such as the deviation change before and after voltage regulation, power change, and the change in the overall system efficiency to comprehensively measure the effect of voltage balancing regulation. The balanced effect result can clearly indicate whether the voltage balancing operation is effective, which aspects of the system have been specifically improved, and whether there is still room for further optimization. These analysis results provide a basis for the further adjustment and optimization of the system, helping the operation and maintenance personnel to decide how to further improve the working efficiency of the system.

[0091] For example, assume that in a string containing 20 photovoltaic modules, after voltage regulation, the regulated voltage data is collected and standardized. After standardization, the voltage data of each module is within [-1, 1], enabling data comparison between different modules on the same scale. Then, the deviation is calculated between these standardized data and the voltage data before regulation. The result shows that the deviation value after regulation is reduced by 30% compared to before regulation, indicating that the voltage regulation effectively improves the consistency of module voltages. Next, based on the improved voltage, the output power of each module is calculated to obtain the power change before and after regulation. The result shows that the power output of the entire string increases by approximately 10%. Statistical analysis of these power change values reveals that the power of 15 out of 20 modules increases significantly, with an average power increase of 12%, while the power increase of the remaining 5 modules is relatively small. Finally, a comprehensive analysis is performed by combining the efficiency parameter and improvement index to obtain the balanced effect result, indicating that after voltage balancing regulation, the overall power generation efficiency of the system increases by approximately 8%, and the voltage consistency between modules is significantly improved. This balanced effect result provides a clear direction for subsequent system maintenance and further optimization.

[0092] The component-level voltage balancing method for a photovoltaic system in the embodiments of the present application has been described above. Next, the component-level voltage balancing device for a photovoltaic system in the embodiments of the present application will be described. Please refer to Figure 2 , an embodiment of the component-level voltage balancing device for a photovoltaic system in the embodiments of the present application includes:

[0093] A collection module 201, configured to perform multi-channel synchronous voltage data collection on each photovoltaic module in a photovoltaic string to obtain a string voltage data set;

[0094] A calculation module 202, configured to perform voltage deviation calculation and analysis on the string voltage data set to obtain a voltage diagnosis result;

[0095] An equalization module 203, configured to perform equalization target calculation on the voltage diagnosis result to obtain target voltage parameters;

[0096] A configuration module 204, configured to perform MPPT controller configuration on the target voltage parameter to obtain a control parameter scheme;

[0097] A control module 205, configured to perform power optimization control according to the control parameter scheme to obtain voltage regulation data;

[0098] A comparison module 206, configured to perform comparison and analysis on the voltage regulation data and the string voltage data set to obtain an equalization effect result.

[0099] Through the collaborative cooperation of the above-mentioned various components, through multi-channel synchronous voltage data acquisition, the accuracy and timeliness of the voltage data of each photovoltaic module in the photovoltaic string are ensured, providing a solid foundation for subsequent analysis and processing. This high-precision data acquisition method can more comprehensively reflect the actual voltage state of photovoltaic modules compared with traditional manual or decentralized acquisition, avoiding misjudgment and improper adjustment caused by data errors. By calculating and analyzing the voltage deviation of the string voltage data set, not only the voltage diagnosis result is obtained, but also the problem of voltage imbalance can be discovered and solved in time. This process not only considers the average value of the voltage, but also conducts a detailed analysis of the voltage deviation through standard deviation and threshold classification processing, thereby ensuring the accuracy and pertinence of voltage equalization. This comprehensive and in-depth analysis method helps the operation and maintenance personnel accurately judge the operation state of photovoltaic modules, take measures in time, and avoid potential safety hazards. Next, through the equalization target calculation, the target voltage parameter is obtained, and based on this, the MPPT controller is configured to achieve precise adjustment of the voltage of photovoltaic modules. This process not only considers the voltage value at the maximum power point, but also combines the priority and adjustable range of the components with over-limit deviation, ensuring the rationality and effectiveness of voltage regulation. This adaptive controller configuration method can flexibly adjust the voltage level of photovoltaic modules according to different lighting and environmental conditions, improving the response speed and regulation accuracy of the system., through power optimization control and comparison and analysis of voltage regulation data, an equalization effect result is obtained. This process not only focuses on the improvement of the voltage, but also comprehensively evaluates the impact of voltage equalization on the system power and efficiency through methods such as standardization processing, deviation calculation, power change value statistical analysis, and efficiency parameter evaluation.

[0100] As mentioned above, the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on 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 embodiments of the present application.

Claims

1. A component-level voltage equalization method for a photovoltaic system, characterized in that The component-level voltage equalization method of the photovoltaic system includes: Performing multi-channel synchronous voltage data acquisition on each photovoltaic component in the photovoltaic string to obtain a string voltage data set; Calculating and analyzing voltage deviation of the string voltage data set to obtain a voltage diagnosis result; Calculating an equalization target for the voltage diagnosis result to obtain target voltage parameters; Configuring an MPPT controller for the target voltage parameters to obtain a control parameter scheme; Performing power optimization control according to the control parameter scheme to obtain voltage regulation data; Comparing and analyzing the voltage regulation data with the string voltage data set to obtain an equalization effect result.

2. The method for component-level voltage equalization of a photovoltaic system according to claim 1, wherein, The performing multi-channel synchronous voltage data acquisition on each photovoltaic component in the photovoltaic string to obtain a string voltage data set includes: Performing clock synchronization settings on the master station and slave stations in the photovoltaic string to obtain a synchronous clock signal; Performing IEEE1588 time synchronization processing on the synchronous clock signal to obtain the acquisition time reference for each slave station; Sending a synchronous acquisition command to each slave station according to the acquisition time reference to obtain component voltage sampling values; Performing POWERBUS bus transmission processing on the component voltage sampling values to obtain voltage transmission data; Summarizing and formatting the voltage transmission data to obtain the string voltage data set.

3. The component-level voltage equalization method for a photovoltaic system according to claim 1, wherein The calculating and analyzing voltage deviation of the string voltage data set to obtain a voltage diagnosis result includes: Calculating the average value of the string voltage data set to obtain a reference voltage value; Calculating the difference between each component voltage in the string voltage data set and the reference voltage value to obtain voltage deviation data; Calculating the standard deviation of the voltage deviation data to obtain deviation statistical parameters; Performing threshold classification processing on the voltage deviation data to obtain a component classification result; Performing comprehensive processing on the component classification result and the deviation statistical parameters to obtain the voltage diagnosis result.

4. The component-level voltage equalization method for a photovoltaic system according to claim 1, wherein The calculating an equalization target for the voltage diagnosis result to obtain target voltage parameters includes: Determining the maximum power point voltage for the voltage diagnosis result to obtain a reference voltage value; Performing priority sorting on the components with over-limit deviation in the voltage diagnosis result to obtain an adjustment sequence; Calculating the voltage increase and decrease amount for each component according to the reference voltage value to obtain adjustment amount data; Verifying the safety range of the adjustment amount data to obtain an adjustable interval; Integrating parameters according to the adjustment sequence and the adjustable interval to obtain the target voltage parameters.

5. The component-level voltage equalization method of the photovoltaic system according to claim 1, wherein The configuring an MPPT controller for the target voltage parameters to obtain a control parameter scheme includes: Setting the LLC resonant circuit frequency for the target voltage parameters to obtain a working frequency range; Calculating the initial PWM duty cycle value for the target voltage parameters to obtain modulation parameters; Setting the controller response parameters according to the working frequency range to obtain dynamic characteristic parameters; Verifying the stability of the dynamic characteristic parameters to obtain a correction coefficient; Calibrating the modulation parameters according to the correction coefficient to obtain the control parameter scheme.

6. The component-level voltage equalization method for a photovoltaic system according to claim 1, wherein, Performing power optimization control according to the control parameter scheme to obtain voltage regulation data, including: Performing three-point comparison sampling on the control parameter scheme to obtain power characteristic points; Determining the maximum value of the power characteristic points to obtain the current optimal point; Adjusting the PWM duty cycle according to the current optimal point to obtain a control signal; Transmitting the control signal through PLC carrier to obtain an execution instruction; Performing voltage regulation processing according to the execution instruction to obtain the voltage regulation data.

7. The method for component-level voltage equalization of a photovoltaic system according to claim 1, characterized in that Comparing and analyzing the voltage regulation data with the string voltage data set to obtain an equalization effect result, including: Performing normalization processing on the voltage regulation data to obtain normalized data; Calculating the deviation according to the normalized data and the string voltage data set to obtain an improvement index; Calculating the string power for the improvement index to obtain a power change value; Performing statistical analysis on the power change value to obtain an efficiency parameter; Performing comprehensive analysis according to the efficiency parameter and the improvement index to obtain the equalization effect result.

8. A component-level voltage equalization device for a photovoltaic system, which is used to implement the component-level voltage equalization method of the photovoltaic system according to any one of claims 1-7, characterized in that, The component-level voltage equalization device of the photovoltaic system includes: An acquisition module for performing multi-channel synchronous voltage data acquisition on each photovoltaic component in the photovoltaic string to obtain a string voltage data set; A calculation module for calculating and analyzing the voltage deviation of the string voltage data set to obtain a voltage diagnosis result; An equalization module for calculating an equalization target for the voltage diagnosis result to obtain target voltage parameters; A configuration module for configuring the MPPT controller with the target voltage parameters to obtain a control parameter scheme; A control module for performing power optimization control according to the control parameter scheme to obtain voltage regulation data; A comparison module for comparing and analyzing the voltage regulation data with the string voltage data set to obtain an equalization effect result.

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