Charging control and energy storage management method, system and device based on photovoltaic cell

Abstract

The invention discloses a charging control and energy storage management method, system and device based on a photovoltaic cell, and relates to the technical field of photovoltaic cells. The charging control and energy storage management method based on the photovoltaic cell comprises the following steps: obtaining a full charge state evaluation value; obtaining a stability evaluation score; obtaining an effectiveness evaluation index; and storing electric energy. According to the invention, the full-charge state evaluation value of the photovoltaic cell in the charging stage is obtained, the charging parameter of the photovoltaic cell is dynamically regulated and controlled based on the obtained full-charge state evaluation value, and then whether to make an energy storage management strategy is judged based on the obtained stability evaluation score. And finally, the change condition of the key information data in the floating charge stage is monitored in real time to obtain an effectiveness evaluation index, and whether charging is completed is judged based on the obtained effectiveness evaluation index, so that the effect of improving the energy storage management reliability of the photovoltaic cell is achieved. The problem that the relevance between the photovoltaic cell and the floating charge state in the energy storage management process is not high in the prior art is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cells, and in particular to a charging control and energy storage management method, system and device based on photovoltaic cells. Background Art

[0002] With the continuous growth of global energy demand and the increasing awareness of environmental protection, the development and utilization of renewable energy has become the focus of attention of countries around the world. Photovoltaic cells, as an important renewable energy technology, have been widely used in power systems. However, the output power of photovoltaic cells is affected by many factors such as weather, light intensity, temperature, etc., and is intermittent and unstable, which poses challenges to the stable operation of the power system and the electricity demand of users. In order to effectively deal with the instability of photovoltaic cell output power, charging control and energy storage management methods have emerged. By accurately controlling the charging process of photovoltaic cells and reasonably managing the charging and discharging state of energy storage equipment, this not only improves the stability and reliability of the power system, but also reduces the electricity cost of users, and promotes the widespread application of renewable energy.

[0003] Existing technologies use a battery management system to monitor and manage the battery charging process in real time and use polarization voltage control to detect the battery's full charge status. At the same time, through real-time monitoring and analysis of energy demand and energy supply, it automatically adjusts the operating status of photovoltaic power generation and energy storage, thereby realizing intelligent charging control and energy storage management of photovoltaic batteries.

[0004] For example, the battery charging control device and method and the photovoltaic energy storage system disclosed in the invention patent with announcement number: CN111262313B include: generating a first current according to a unilateral bus voltage limit value and the larger of the positive and negative bus voltages; generating a second current according to a preset voltage; taking the smaller of the first current and the second current as output; generating a first voltage according to the difference between the positive and negative bus voltages; generating a second voltage according to the output of a small unit; generating a first duty cycle for adjusting the voltage according to the first voltage and the second voltage; generating a second duty cycle for adjusting the voltage according to the first voltage and the second voltage.

[0005] For example, the battery charging control method, energy storage device and photovoltaic energy storage system disclosed in the patent application with publication number: CN118971301A include: when the battery is in a floating charge state, obtaining the actual charging voltage, actual charging current, actual charging power of the battery and the actual power generation voltage of the power generation module; obtaining a first adjustment parameter based on the actual charging voltage, a preset floating charge voltage and the actual charging current; obtaining a second adjustment parameter based on the actual charging power and the limit charging power of the battery; obtaining a target power generation voltage of the power generation module based on the first adjustment parameter, the second adjustment parameter and the actual power generation voltage of the power generation module; adjusting the actual power generation voltage of the power generation module based on the target power generation voltage to keep the battery in a floating charge state.

[0006] However, in the process of implementing the technical solution of the invention in the embodiments of the present application, the present application found that the above technology has at least the following technical problems:

[0007] In the prior art, the photovoltaic battery group in the existing charging control is not highly balanced during the charging process under the same charging conditions, which limits the application scenarios of the existing energy storage management strategy and causes a problem of low correlation between the photovoltaic battery and the floating charge state during the energy storage management process. Summary of the invention

[0008] The embodiments of the present application solve the problem in the prior art that the photovoltaic cell has a low correlation with the floating charge state during the energy storage management process by providing a charging control and energy storage management method, system and device based on the photovoltaic cell, thereby improving the reliability of the photovoltaic cell energy storage management.

[0009] The embodiment of the present application provides a charging control and energy storage management method based on photovoltaic cells, comprising the following steps: step one, reading the battery status information sent by the battery BMS through the communication interface, and monitoring the changes of the battery status information in real time during the charging stage to obtain a full charge state evaluation value, wherein the full charge state evaluation value is used to evaluate the degree of matching between the photovoltaic cell and the floating charge mode during the current charging process; step two, dynamically adjusting the charging parameters of the photovoltaic cell based on the obtained full charge state evaluation value, monitoring the charging process of the photovoltaic cell in the floating charge stage in real time according to the dynamically adjusted charging parameters to obtain a stability evaluation score, and judging based on the obtained stability evaluation score Whether to formulate an energy storage management strategy, the stability assessment score is used to quantify the charging stability of the photovoltaic battery in the floating charging stage; step three, if the energy storage management strategy is formulated, the key information data of the photovoltaic battery in the energy storage management process is monitored in real time, and the changes of the key information data in the floating charging stage are monitored in real time to obtain the effectiveness assessment index, and the effectiveness assessment index is used to reflect the effectiveness of the energy storage management strategy and the efficiency of the energy storage management; step four, based on the obtained effectiveness assessment index, determine whether the charging is completed. If so, store the electric energy of the photovoltaic battery after charging, otherwise adjust the energy storage management strategy and continue to monitor the charging process of the photovoltaic battery.

[0010] Furthermore, the full charge status evaluation value is obtained by the following method: counting the initial charging parameters of the photovoltaic cell at the beginning of a preset charging period and obtaining the actual charging parameters of the photovoltaic cell after the preset charging period ends, and obtaining the temperature deviation, voltage deviation, current deviation and power deviation accordingly, the initial charging parameters including initial temperature, initial voltage, initial current and initial power, and the actual charging parameters including actual temperature, actual voltage, actual current and actual power; according to the actual light intensity of the photovoltaic cell in the preset charging period, and in combination with the reference temperature deviation, reference voltage deviation, reference current deviation, reference power deviation and maximum allowable light intensity in the database, the full charge status evaluation value is obtained; the temperature deviation is the difference between the actual temperature and the initial temperature; the voltage deviation is the difference between the actual voltage and the initial voltage; the current deviation is the difference between the actual current and the initial current; the power deviation is the difference between the actual power and the initial power.

[0011] Furthermore, the stability evaluation score is obtained by the following method: real-time monitoring of the changes in the floating charge voltage and the floating charge current of the photovoltaic cell during the floating charge stage to obtain the extreme values ​​of the floating charge parameters, and obtaining the average floating charge voltage and the average floating charge current of the photovoltaic cell at the end of the floating charge stage, wherein the extreme values ​​of the floating charge parameters include the maximum floating charge voltage, the maximum floating charge current, the minimum floating charge voltage and the minimum floating charge current; respectively counting the duration of the extreme values ​​of the floating charge parameters during the floating charge stage to obtain the proportion of the floating charge parameter duration, and combining the obtained average floating charge voltage and the average floating charge current to obtain the stability evaluation score, wherein the proportion of the floating charge parameter duration includes a first proportion, a second proportion, a third proportion and a fourth proportion.

[0012] Furthermore, the specific steps for obtaining the effectiveness evaluation index are: counting the first duty cycle and the second duty cycle of the photovoltaic cell at the end of the preset floating charge period, and obtaining the first duty cycle coefficient and the second duty cycle coefficient in combination with the reference first duty cycle and the reference second duty cycle in the database; counting the floating charge amount and the total floating charge time of the photovoltaic cell in the floating charge stage, and obtaining the floating charge amount coefficient and the total floating charge time coefficient in combination with the reference floating charge amount and the reference total floating charge time in the database, and at the same time combining the obtained stability evaluation score to obtain the effectiveness evaluation index; the first duty cycle coefficient is obtained by processing the stability evaluation score, the first duty cycle and the reference first duty cycle; the second duty cycle coefficient is obtained by processing the stability evaluation score, the second duty cycle and the reference second duty cycle; the floating charge coefficient is obtained by processing the floating charge amount and the reference floating charge amount; the total floating charge time coefficient is obtained by processing the total floating charge time and the reference total floating charge time.

[0013] Furthermore, the specific limiting expression of the effectiveness evaluation index is:

[0014] ;

[0015] In the formula, e is a natural constant, It represents the effectiveness evaluation index of the photovoltaic battery corresponding to the floating charging process when performing energy storage management. Indicates the stability evaluation score of the photovoltaic cell during floating charge. Indicates the floating charge capacity coefficient of the photovoltaic cell at the end of the preset floating charge period. Indicates the total float charge duration coefficient of the photovoltaic cell at the end of the preset float charge period. Indicates the first duty cycle coefficient of the photovoltaic cell at the end of the preset floating charge period, Indicates the second duty cycle coefficient of the photovoltaic cell at the end of the preset floating charge period.

[0016] The embodiment of the present application provides a charging control and energy storage management system based on photovoltaic cells, including: a full-charge state evaluation value acquisition module, a stability evaluation score acquisition module, an effectiveness evaluation index acquisition module and an electric energy storage module; wherein the full-charge state evaluation value acquisition module is used to read the battery state information sent by the battery BMS through the communication interface, and at the same time monitor the change of the battery state information in the charging stage in real time to obtain the full-charge state evaluation value, and the full-charge state evaluation value is used to evaluate the degree of matching between the photovoltaic cell and the floating charge mode during the current charging process; the stability evaluation score acquisition module is used to dynamically adjust the charging parameters of the photovoltaic cell based on the acquired full-charge state evaluation value, and monitor the charging process of the photovoltaic cell in the floating charge stage in real time according to the dynamically adjusted charging parameters to obtain A stability evaluation score is obtained, and at the same time, it is determined whether to formulate an energy storage management strategy based on the obtained stability evaluation score. The stability evaluation score is used to quantify the charging stability of the photovoltaic battery in the floating charging stage; the effectiveness evaluation index acquisition module is used to monitor the key information data of the photovoltaic battery in the energy storage management process in real time if an energy storage management strategy is formulated, and at the same time, it monitors the changes of the key information data in the floating charging stage in real time to obtain the effectiveness evaluation index, and the effectiveness evaluation index is used to reflect the effectiveness of the energy storage management strategy and the efficiency of the energy storage management; the electric energy storage module is used to determine whether the charging is completed based on the obtained effectiveness evaluation index. If so, the electric energy of the photovoltaic battery after charging is stored, otherwise the energy storage management strategy is adjusted and the charging process of the photovoltaic battery is continued to be monitored.

[0017] An embodiment of the present application provides a device for applying the charging control and energy storage management method based on photovoltaic cells, including: a voltage sensor, a current sensor, a temperature sensor, a light intensity sensor, a memory and a processor; the voltage sensor is used to obtain the actual voltage and floating charge voltage of the photovoltaic cell during the charging process; the current sensor is used to obtain the actual current and floating charge current of the photovoltaic cell during the charging process; the temperature sensor is used to obtain the actual temperature of the surface of the photovoltaic cell during the charging process; the light intensity sensor is used to obtain the actual light intensity on the surface of the photovoltaic cell during the charging process; the memory is used to store the obtained full charge status evaluation value, stability evaluation score, effectiveness evaluation index and the electric energy after the photovoltaic cell is charged; the processor is used to pre-process the battery status information sent by the battery BMS.

[0018] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0019] 1. By real-time monitoring of changes in battery status information during the charging stage to obtain a full charge status evaluation value, and dynamically adjusting the charging parameters of the photovoltaic battery based on the obtained full charge status evaluation value, and then judging whether to formulate an energy storage management strategy based on the obtained stability evaluation score, finally, real-time monitoring of changes in key information data during the floating charge stage to obtain effectiveness evaluation indicators, and judging whether charging is completed based on the obtained effectiveness evaluation indicators, thereby achieving precise control of the photovoltaic battery charging process, and then achieving improved reliability of photovoltaic battery energy storage management, and effectively solving the problem of low correlation between photovoltaic batteries and the floating charge state in the energy storage management process in the prior art.

[0020] 2. By real-time monitoring the changes in the floating charge voltage and floating charge current of photovoltaic cells during the floating charge stage, the extreme values ​​of the floating charge parameters are obtained. At the same time, the duration of the extreme values ​​of the floating charge parameters during the floating charge stage is counted to obtain the proportion of the floating charge parameter duration. The stability assessment score is obtained by combining the obtained average floating charge voltage and average floating charge current, thereby improving the accuracy of obtaining the stability assessment score, and further achieving a more accurate assessment of the charging stability of photovoltaic cells during the floating charge stage.

[0021] 3. By counting the first duty cycle, second duty cycle, floating charge and total floating charge time of the photovoltaic battery at the end of the preset floating charge period, and combining the reference first duty cycle, reference second duty cycle, reference floating charge and reference total floating charge time in the database, the first duty cycle coefficient, second duty cycle coefficient, floating charge coefficient and total floating charge time coefficient are obtained. At the same time, the effectiveness evaluation index is obtained in combination with the stability evaluation score, thereby achieving an improvement in the accuracy of obtaining the effectiveness evaluation index, and then achieving a more accurate evaluation of the effectiveness of the implementation of the energy storage management strategy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A flow chart of a photovoltaic cell-based charging control and energy storage management method provided in an embodiment of the present application;

[0023] Figure 2 A circuit diagram for charging control of a photovoltaic inverter provided in an embodiment of the present application;

[0024] Figure 3 A schematic diagram of the structure of a photovoltaic cell-based charging control and energy storage management system provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] The embodiments of the present application solve the problem of low correlation between photovoltaic cells and floating charge status in the energy storage management process in the prior art by providing a charging control and energy storage management method, system and device based on photovoltaic cells. The battery status information sent by the battery BMS is read through a communication interface, and the changes of the battery status information in the charging stage are monitored in real time to obtain a full charge status evaluation value. Then, the charging parameters of the photovoltaic cell are dynamically adjusted based on the obtained full charge status evaluation value. Then, the charging process of the photovoltaic cell in the floating charge stage is monitored in real time according to the dynamically adjusted charging parameters to obtain a stability evaluation score. At the same time, it is determined whether to formulate an energy storage management strategy based on the obtained stability evaluation score. If an energy storage management strategy is formulated, the key information data of the photovoltaic cell in the energy storage management process is monitored in real time. At the same time, the changes of the key information data in the floating charge stage are monitored in real time to obtain an effectiveness evaluation index. Finally, it is determined whether the charging is completed based on the obtained effectiveness evaluation index. If so, the electric energy of the photovoltaic cell after charging is stored. Otherwise, the energy storage management strategy is adjusted and the charging process of the photovoltaic cell is continuously monitored, thereby improving the reliability of photovoltaic battery energy storage management.

[0026] The technical solution in the embodiment of the present application is to solve the problem that the above photovoltaic cells have low correlation with the floating charge state during the energy storage management process. The overall idea is as follows:

[0027] The charging parameters of the photovoltaic battery are dynamically adjusted by the full charge status evaluation value, and then it is determined whether to formulate an energy storage management strategy based on the obtained stability evaluation score. Finally, the changes in key information data in the floating charge stage are monitored in real time to obtain effectiveness evaluation indicators. At the same time, it is determined whether the charging is completed based on the obtained effectiveness evaluation indicators, thereby improving the reliability of photovoltaic battery energy storage management.

[0028] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0029] like Figure 1As shown, it is a flow chart of a charging control and energy storage management method based on a photovoltaic cell provided in an embodiment of the present application, and the method includes the following steps: Step 1, the photovoltaic inverter reads the battery status information sent by the battery BMS through the communication interface, and monitors the changes of the battery status information in real time during the charging stage to obtain a full charge state evaluation value, and the full charge state evaluation value is used to evaluate the degree of matching between the photovoltaic cell and the floating charge mode during the current charging process; Step 2, based on the obtained full charge state evaluation value, the charging parameters of the photovoltaic cell are dynamically adjusted, and the charging process of the photovoltaic cell in the floating charge stage is monitored in real time according to the dynamically adjusted charging parameters to obtain a stability evaluation score, and based on the obtained The stability assessment score determines whether to formulate an energy storage management strategy. The stability assessment score is used to quantify the charging stability of photovoltaic cells in the floating charging stage. Step three, if an energy storage management strategy is formulated, the key information data of the photovoltaic cells in the energy storage management process is monitored in real time, and the changes of the key information data in the floating charging stage are monitored in real time to obtain the effectiveness evaluation index. The effectiveness evaluation index is used to reflect the effectiveness of the energy storage management strategy and the efficiency of energy storage management. Step four, based on the obtained effectiveness evaluation index, it is determined whether the charging is completed. If so, the electric energy of the photovoltaic battery after charging is stored, otherwise the energy storage management strategy is adjusted and the charging process of the photovoltaic battery continues to be monitored.

[0030] In this embodiment, the photovoltaic inverter is connected to the communication interface between the battery BMS (Battery Management System) of the photovoltaic cell. Among them, the photovoltaic inverter contains a voltage regulation circuit to generate the required floating charge voltage, and is usually equipped with a voltage sensor, a current sensor, and a temperature sensor to accurately control the floating charge voltage. The battery BMS of the photovoltaic cell is stored inside the photovoltaic cell and is a system for monitoring, controlling and managing the battery pack. The above-mentioned communication interface, such as RS485 and CAN bus, can communicate remotely with the photovoltaic cell and read the battery status information.

[0031] Battery status information includes voltage, current, temperature, internal resistance and remaining power; key information data includes charging time, charging amount, and the first duty cycle and the second duty cycle in the floating charge stage, wherein the first duty cycle indicates the ratio of the total time that the photovoltaic inverter provides charging current to the photovoltaic cell to the total time of the floating charge stage, and the second duty cycle indicates the ratio of the total time that the photovoltaic inverter stops providing charging current to the photovoltaic cell to the total time of the floating charge stage, wherein the total time of providing charging current to the photovoltaic cell, the total time of stopping providing charging current to the photovoltaic cell and the total time of the floating charge stage are all recorded in real time by the timer in the battery BMS.

[0032] The charging stage includes the pre-charging stage, constant current charging stage, constant voltage charging stage and floating charging stage. Among them, the pre-charging stage means waking up the photovoltaic cell and reducing the impact current of the photovoltaic cell during the charging process, the constant current charging stage means fast charging the photovoltaic cell under a constant current state, the constant voltage charging stage means charging the photovoltaic cell under a constant voltage state until the photovoltaic cell is close to a fully charged state, and the floating charging stage means balancing the natural discharge of the photovoltaic cell and maintaining the photovoltaic cell in a fully charged state for a long time.

[0033] like Figure 2 As shown, it is a circuit diagram of charging control of the photovoltaic inverter provided in an embodiment of the present application. In this example, by accurately controlling the charging process of the photovoltaic cell, the multi-stage charging strategy can reduce the number and depth of charge and discharge cycles of the photovoltaic cell, thereby effectively extending the service life of the battery. Secondly, the collaborative work of the photovoltaic inverter and the battery BMS realizes the intelligent management of the battery charging process, and can perform adaptive adjustments according to the actual situation of the battery, thereby improving the controllability and stability of the charging process, thereby achieving an improvement in the reliability of photovoltaic battery energy storage management.

[0034] Furthermore, the full charge status evaluation value is obtained by the following method: counting the initial charging parameters of the photovoltaic cell at the beginning of the preset charging period (displayed by the battery BMS display screen) and obtaining the actual charging parameters of the photovoltaic cell after the preset charging period ends, and obtaining the temperature deviation, voltage deviation, current deviation and power deviation accordingly. The initial charging parameters include initial temperature, initial voltage, initial current and initial power, and the actual charging parameters include actual temperature (the temperature of the photovoltaic cell itself during the charging process), actual voltage, actual current and actual power; according to the actual light intensity of the photovoltaic cell in the preset charging period (excluding the floating charge stage), and combined with the reference temperature deviation, reference voltage deviation, reference current deviation, reference power deviation and maximum allowable light intensity in the database, the full charge status evaluation value is obtained; the temperature deviation is the difference between the actual temperature and the initial temperature, and the initial temperature usually refers to room temperature, such as 24°C; the voltage deviation is the difference between the actual voltage and the initial voltage; the current deviation is the difference between the actual current and the initial current; the power deviation is the difference between the actual power and the initial power.

[0035] Among them, the specific restriction expression of the full charge state evaluation value is:

[0036] ;

[0037] ;

[0038] ;

[0039] ;

[0040] ;

[0041] In the formula, e is a natural constant, Indicates the evaluation value of the full charge state of the photovoltaic battery within the preset charging period. Indicates the actual light intensity on the surface of the photovoltaic cell at the end of the preset charging period, Indicates the maximum permissible light intensity, Indicates the voltage deviation of the photovoltaic cell at the end of the preset charging period, Indicates that the photovoltaic battery has reached the end of the preset charging period. Represents the initial voltage of the photovoltaic cell before the preset charging period begins, Indicates the reference voltage deviation, Indicates the temperature deviation of the photovoltaic cell at the end of the preset charging period, Indicates the actual temperature of the photovoltaic cell surface at the end of the preset charging period, represents the initial temperature of the photovoltaic cell surface at the end of the preset charging period, represents the reference temperature deviation, Indicates the current deviation of the photovoltaic cell at the end of the preset charging period, Indicates the actual current of the photovoltaic cell at the end of the preset charging period, Represents the initial current of the photovoltaic cell before the preset charging period begins, represents the reference current deviation, Indicates the power deviation of the photovoltaic cell at the end of the preset charging period, Indicates the actual charge level of the photovoltaic battery at the end of the preset charging period. Indicates the initial charge of the photovoltaic cell before the preset charging period begins. Indicates the reference power deviation.

[0042] In this embodiment, the reference temperature deviation, reference voltage deviation, reference current deviation and reference power deviation are respectively represented by the sum and average of the historical temperature deviation, historical voltage deviation, historical current deviation and historical power deviation of the photovoltaic cells in the database at the end of each historical charging period, and the maximum allowable light intensity is the maximum value of the historical light intensity in the illumination area where the photovoltaic cells in the database are located.

[0043] The aforementioned database is a database for storing various types of setting data established before the design of charging control and energy storage management methods, systems and devices based on photovoltaic cells. The database includes but is not limited to preset full charge state evaluation values, stability evaluation threshold ranges, reference first duty cycles and reference second duty cycles, and preset floating charge periods. Various values ​​therein are directly set by technical personnel, wherein the setting basis of the preset full charge state evaluation value may be determined according to the actual charging scenario of the photovoltaic cell. For example, the preset full charge state evaluation value is represented by the sum and average of the historical full charge state evaluation values ​​of the photovoltaic cells in the database in each historical charging period. In addition, various values ​​in the database may be set and fine-tuned by technical personnel according to actual debugging.

[0044] It should be understood that the full charge state evaluation value increases with the increase of actual light intensity and decreases with the actual temperature deviation (i.e. ), actual voltage deviation (i.e. ), actual current deviation (i.e. ) and actual power deviation (i.e. ) increases and decreases.

[0045] It should be noted that the actual light intensity also indirectly affects the values ​​of the actual temperature deviation and the actual power deviation. When the actual light intensity increases and does not exceed the maximum allowable light intensity, the number of photons received by the photovoltaic cell increases, and the electrical energy generated also increases accordingly. In this process, the temperature of the photovoltaic cell will increase due to the energy conversion of photons and the heat generated by the internal resistor. In this case, the increase in the electrical energy of the photovoltaic cell speeds up the charging speed of the photovoltaic cell, which means that in the same charging period, the photovoltaic cell can be charged with more electricity, resulting in a decrease in the actual power deviation.

[0046] The actual power deviation also indirectly affects the values ​​of the actual voltage deviation and the actual current deviation. When the actual power deviation increases, in order to speed up the charging speed and reach the full charge state as soon as possible, the charging voltage is usually increased to provide more charging energy, which will cause the actual voltage deviation to increase; similarly, in order to speed up the charging speed, the charging current also needs to be increased, which will cause the actual current deviation to increase.

[0047] By considering the above-mentioned indirect influence mechanism, it is helpful to achieve more accurate photovoltaic battery energy storage management. This management strategy not only considers the direct influence of light intensity on the full charge state evaluation value, but also considers the indirect influence of light intensity on voltage deviation and current deviation through affecting temperature deviation and power deviation. This comprehensive consideration helps to improve the reliability and safety of photovoltaic battery energy storage management, and effectively solves the problem of low correlation between photovoltaic batteries and floating charge state in the energy storage management process in the prior art.

[0048] Furthermore, the specific steps of dynamically regulating the charging parameters of the photovoltaic battery based on the acquired full charge state evaluation value include: E1, judging whether the acquired full charge state evaluation value is not less than the preset full charge state evaluation value, if so, receiving the floating charge stage charging instruction sent by the battery BMS through the communication interface and entering the floating charge mode, that is, entering the floating charge stage charging, otherwise executing E2; E2, if the charging process of the photovoltaic battery is in the constant current charging stage, prompting the preset personnel to increase the charging voltage through the communication interface to speed up the charging speed, this process keeps the charging current unchanged and the increased charging voltage is less than the rated voltage and the maximum allowable charging voltage of the photovoltaic battery, if the charging process of the photovoltaic battery is in the constant voltage charging stage, prompting the preset personnel to increase the charging current through the communication interface to speed up the charging speed, this process keeps the charging voltage unchanged and the increased charging current is less than the rated current and the maximum allowable charging current of the photovoltaic battery; E3, continuing to monitor the charging process of the photovoltaic battery in the preset charging period according to the dynamically regulated charging parameters until the acquired full charge state evaluation value is not less than the preset full charge state evaluation value.

[0049] In this embodiment, compared with the prior art, this example interacts with the battery BMS through a communication interface (i.e., by real-time monitoring of the full charge status evaluation value of the photovoltaic battery, and dynamically adjusting the charging parameters according to the evaluation value, increasing the charging voltage in the constant current charging stage, and increasing the charging current in the constant voltage charging stage, thereby effectively speeding up the charging speed and improving the charging efficiency), receiving instructions and feeding back the charging status, thereby realizing closed-loop charging control of the photovoltaic battery, which not only improves the accuracy and reliability of the charging control, but also facilitates the user to monitor and manage the charging process, which is of great significance for improving the utilization rate of photovoltaic cells and promoting the development of green energy.

[0050] Furthermore, the stability assessment score is obtained by the following method: real-time monitoring of the changes in the floating charge voltage and the floating charge current of the photovoltaic cells during the floating charge stage to obtain the extreme values ​​of the floating charge parameters, and obtaining the average floating charge voltage and the average floating charge current of the photovoltaic cells at the end of the floating charge stage. The extreme values ​​of the floating charge parameters include the maximum floating charge voltage, the maximum floating charge current, the minimum floating charge voltage and the minimum floating charge current; respectively counting the duration of the extreme values ​​of the floating charge parameters during the floating charge stage to obtain the proportion of the floating charge parameter duration, and combining the obtained average floating charge voltage and the average floating charge current to obtain the stability assessment score. The floating charge parameter duration proportion includes the first proportion, the second proportion, the third proportion and the fourth proportion.

[0051] Among them, when the obtained full charge state evaluation value is not less than the preset full charge state evaluation value, the specific restriction expression of the stability evaluation score is:

[0052] ;

[0053] In the formula, e is a natural constant, It indicates the stability evaluation score of the photovoltaic cell during the floating charge process. The floating charge process is the charging process under the floating charge stage. Indicates the average floating charge voltage of the photovoltaic cell during the floating charge process. Indicates the maximum floating charge voltage of the photovoltaic cell during the floating charge process. Indicates the minimum floating charge voltage of the photovoltaic cell during the floating charge process. It represents the average floating charge current of the photovoltaic cell during the floating charge process. Indicates the maximum floating charge current of the photovoltaic battery during the floating charge process. Indicates the minimum floating charge current of the photovoltaic battery during the floating charge process. It indicates the first proportion of the maximum floating charge voltage generated by the photovoltaic cell during the floating charge process. It indicates the second largest proportion of floating charge current generated by photovoltaic cells during floating charge. It indicates the third percentage of the minimum floating charge voltage generated by photovoltaic cells during floating charge. It indicates the fourth percentage of the minimum floating charge current generated by photovoltaic cells during the floating charge process.

[0054] In this embodiment, the first ratio represents the ratio of the duration of the maximum floating charge voltage in the floating charge stage to the total floating charge time, the second ratio represents the ratio of the duration of the maximum floating charge current in the floating charge stage to the total floating charge time, the third ratio represents the ratio of the duration of the minimum floating charge voltage in the floating charge stage to the total floating charge time, and the fourth ratio represents the ratio of the duration of the minimum floating charge current in the floating charge stage to the total floating charge time.

[0055] It should be understood that the stability evaluation score increases with the increase of the average floating charge voltage, the average floating charge current, the third proportion and the fourth proportion, decreases with the increase of the first proportion and the second proportion, and decreases with the floating charge voltage fluctuation deviation (i.e. ) and floating charge current fluctuation deviation (i.e. ) increases and decreases.

[0056] It should be noted that the average float charge voltage and the average float charge current also affect the values ​​of the first proportion and the second proportion respectively. When the average float charge voltage increases, the photovoltaic cell is more likely to reach or approach the maximum float charge voltage during the float charge stage, which means that the duration of the maximum float charge voltage during the float charge stage will be extended, thereby increasing the first proportion; similarly, the increase in the average float charge current means that the photovoltaic cell needs to accept a higher charging current for charging during the float charge stage, which may cause the duration of the maximum float charge current during the float charge stage to increase, thereby increasing the second proportion.

[0057] The third and fourth proportions also indirectly affect the value of the full charge status assessment value. An increase in the third proportion means that the photovoltaic cell maintains a preset floating charge voltage (set by the preset personnel, usually the result of summing and averaging the historical floating charge voltages of the photovoltaic cells in the database during the historical floating charge stages) for most of the time during the floating charge stage, which helps to reduce the stress and loss of the photovoltaic cells and extend the service life of the photovoltaic cells; similarly, an increase in the fourth proportion means that the photovoltaic cell is charged with a smaller floating charge current most of the time during the floating charge stage, which helps to reduce overheating and internal stress of the photovoltaic cells and improves the charging efficiency and safety of the photovoltaic cells.

[0058] By considering the above-mentioned indirect influence mechanism, it is helpful to better understand the behavioral characteristics of photovoltaic cells in the energy storage management process, so as to ensure that photovoltaic cells can maintain stable performance during the floating charge stage, thereby achieving improved reliability and safety of photovoltaic battery energy storage management, and effectively solving the problem of low correlation between photovoltaic cells and the floating charge state during the energy storage management process in the prior art.

[0059] Furthermore, the specific process of determining whether to formulate an energy storage management strategy based on the obtained stability assessment score is as follows: Determine whether the obtained stability assessment score is within the stability assessment threshold range: If the obtained stability assessment score is within the stability assessment threshold range (excluding the case where it is equal to the maximum and minimum values ​​of the historical stability assessment score), it indicates that the stability of the photovoltaic cell during the floating charging process meets the expected demand and an energy storage management strategy is formulated; If the obtained stability assessment score is not within the stability assessment threshold range, it indicates that the stability of the photovoltaic cell during the floating charging process does not meet the expected demand. At this time, no energy storage management strategy is formulated and the floating charging parameters are adjusted. The floating charging process is continued according to the adjusted floating charging parameters and the stability assessment score is re-obtained until the re-obtained stability assessment score is within the stability assessment threshold range.

[0060] Among them, the energy storage management strategy includes temperature control and capacity control; temperature control means that a warning signal is issued when the actual temperature on the surface of the photovoltaic cell reaches the maximum allowable temperature, and capacity control means that a warning signal is issued when the remaining capacity of the photovoltaic cell is 0. The preset personnel receive the above warning signals through the communication interface; the floating charge parameters include the floating charge cycle and the temperature compensation coefficient.

[0061] In this embodiment, the stability assessment threshold range represents the range corresponding to the maximum and minimum values ​​of the historical stability assessment scores of the photovoltaic cells in the database during the floating charge stage; the floating charge cycle refers to the length of time the photovoltaic cell experiences during the floating charge stage. The temperature compensation coefficient is integrated in the battery BMS and is an adjustment parameter for battery charging management. It is used to adaptively adjust the charging voltage of the photovoltaic cell at different temperatures. When the obtained stability assessment score is not within the stability assessment threshold range, the preset personnel receives the floating charge parameter adjustment instruction through the communication interface, and extends the floating charge cycle of the photovoltaic cell by increasing the floating charge cycle parameter in the battery BMS.

[0062] When the room temperature of the photovoltaic cell charging area is 20℃, if the current surface temperature of the photovoltaic cell is equal to the maximum allowable temperature set by the preset personnel, such as 55℃, the current impact caused by high temperature on the photovoltaic cell is reduced by reducing the temperature compensation coefficient in the battery BMS. If the current surface temperature of the photovoltaic cell is equal to the minimum allowable temperature set by the preset personnel, such as -5℃, the current impact caused by low temperature on the photovoltaic cell is reduced by increasing the temperature compensation coefficient in the battery BMS. This helps to ensure the stability and safety of the photovoltaic cell during the floating charge process, thereby improving the charging efficiency of the photovoltaic cell during the floating charge process and the reliability of the floating charge results.

[0063] Furthermore, the specific steps for obtaining the effectiveness evaluation index are as follows: counting the first duty cycle and the second duty cycle of the photovoltaic cell at the end of the preset floating charge period, and obtaining the first duty cycle coefficient and the second duty cycle coefficient in combination with the reference first duty cycle and the reference second duty cycle in the database; counting the floating charge amount and the total floating charge time of the photovoltaic cell during the floating charge stage, and obtaining the floating charge amount coefficient and the total floating charge time coefficient in combination with the reference floating charge amount and the reference total floating charge time in the database, and at the same time combining the obtained stability evaluation score to obtain the effectiveness evaluation index; the first duty cycle coefficient is obtained by processing the stability evaluation score, the first duty cycle and the reference first duty cycle; the second duty cycle coefficient is obtained by processing the stability evaluation score, the second duty cycle and the reference second duty cycle; the floating charge amount coefficient is obtained by processing the floating charge amount and the reference floating charge amount; the total floating charge time coefficient is obtained by processing the total floating charge time and the reference total floating charge time.

[0064] Among them, the reference first proportion, reference second proportion, reference third proportion and reference fourth proportion are respectively represented by the sum and average of the historical first proportion, historical second proportion, historical third proportion and historical fourth proportion of the photovoltaic cells in the database at the end of each historical floating charge period; this example helps to comprehensively reflect the charging performance of photovoltaic cells by considering the proportion of photovoltaic cells in the floating charge stage, the floating charge amount, the total floating charge time and the stability assessment score, and realizes a more accurate assessment of the effectiveness of the photovoltaic battery floating charge results. At the same time, the reference data in the database is taken into consideration, making the effectiveness assessment results more comparable and objective, providing strong support for the performance optimization and operation and maintenance management of photovoltaic cells.

[0065] When the obtained stability evaluation score is within the stability evaluation threshold range, the specific restriction expression of the effectiveness evaluation index is:

[0066] ;

[0067] ;

[0068] ;

[0069] ;

[0070] ;

[0071] In the formula, e is a natural constant, It represents the effectiveness evaluation index of the photovoltaic battery corresponding to the floating charging process when performing energy storage management. Indicates the stability evaluation score of the photovoltaic cell during floating charge. Indicates the floating charge capacity coefficient of the photovoltaic cell at the end of the preset floating charge period. Indicates the floating charge capacity of the photovoltaic cell at the end of the preset floating charge period. Indicates the reference floating charge capacity, Indicates the total float charge duration coefficient of the photovoltaic cell at the end of the preset float charge period. Indicates the total floating charge time of the photovoltaic battery at the end of the preset floating charge period. Indicates the total duration of reference floating charge. Indicates the first duty cycle coefficient of the photovoltaic cell at the end of the preset floating charge period, Indicates the first duty cycle of the photovoltaic cell at the end of the preset floating charge period, represents the reference first duty cycle, Indicates the second duty cycle coefficient of the photovoltaic cell at the end of the preset floating charge period, Indicates the second duty cycle of the photovoltaic cell at the end of the preset floating charge period, Indicates the reference second duty cycle.

[0072] In this embodiment, assuming that the stability evaluation threshold range is 2.0 to 3.0, the statistical table of changes in the effectiveness evaluation index is shown in Table 1:

[0073] Table 1 Statistics of changes in effectiveness evaluation indicators Group Stability evaluation score WEN Float charge coefficient S Total float charge duration coefficient F The first duty cycle coefficient M The second duty cycle coefficient N Effectiveness Evaluation Indicator YOU 1 2.1 0.67 0.55 0.49 0.52 2.459 2 2.2 0.73 0.62 0.49 0.52 2.488 3 2.3 0.78 0.67 0.49 0.52 2.508 4 2.4 0.84 0.77 0.53 0.60 2.514 5 2.4 0.84 0.77 0.59 0.62 2.497 ...... ...... ...... ...... ...... ...... ......

[0074] It should be understood that, from the first, second and third groups of data in Table 1, it can be seen that the effectiveness evaluation index increases with the increase of the stability evaluation score, the floating charge capacity coefficient and the total floating charge time coefficient. From the fourth and fifth groups of data in Table 1, it can be seen that the effectiveness evaluation index decreases with the increase of the first duty cycle coefficient and the second duty cycle coefficient, among which the floating charge capacity coefficient decreases with the floating charge capacity deviation (i.e. ) increases, the total float charge duration coefficient decreases with the total float charge duration deviation (i.e. ) increases, and when the stability evaluation score is a fixed value, the first duty cycle coefficient decreases with the first duty cycle deviation (i.e. ) increases, and the second duty cycle coefficient increases with the second duty cycle deviation (i.e. ) increases with the increase of .

[0075] It should be noted that the stability assessment score also indirectly affects the value of the total float charge time coefficient. When the stability assessment score increases, the photovoltaic cell usually requires a longer total float charge time to maintain its stable state. This is because a stable float charge process enables the photovoltaic cell to better withstand long-term charging without causing overheating or performance degradation. Therefore, an increase in the stability assessment score may indirectly lead to an increase in the total float charge time coefficient to better maintain the performance of the battery.

[0076] The floating charge coefficient also indirectly affects the values ​​of the first duty cycle coefficient and the second duty cycle coefficient. When the floating charge coefficient increases, since the photovoltaic cell obtains sufficient charge in the floating charge state, it may be necessary to reduce the first duty cycle coefficient in the subsequent charging process to avoid overcharging, and in the discharge process, it may be necessary to increase the second duty cycle coefficient to make full use of the battery power.

[0077] By considering the above-mentioned indirect influence mechanisms, we can have a more comprehensive understanding of the interaction between various variables in the energy storage management process of photovoltaic cells, which helps to more accurately predict and regulate the performance and life of the batteries, thereby achieving improved reliability and safety of photovoltaic battery energy storage management, and effectively solving the problem in the prior art that the correlation between photovoltaic cells and the floating charge state in the energy storage management process is not high.

[0078] like Figure 3As shown, it is a structural schematic diagram of a charging control and energy storage management system based on a photovoltaic cell provided in an embodiment of the present application. The charging control and energy storage management system based on a photovoltaic cell provided in an embodiment of the present application includes: a full charge state evaluation value acquisition module, a stability evaluation score acquisition module, a validity evaluation index acquisition module and an electric energy storage module; wherein the full charge state evaluation value acquisition module is used to read the battery state information sent by the battery BMS through the communication interface, and at the same time monitor the change of the battery state information in real time during the charging stage to obtain the full charge state evaluation value, and the full charge state evaluation value is used to evaluate the degree of matching between the photovoltaic cell and the floating charge mode during the current charging process; the stability evaluation score acquisition module is used to dynamically adjust the charging parameters of the photovoltaic cell based on the acquired full charge state evaluation value, and real-time adjust the charging parameters according to the dynamically adjusted charging parameters Monitor the charging process of photovoltaic cells in the floating charging stage to obtain stability evaluation scores, and determine whether to formulate an energy storage management strategy based on the obtained stability evaluation scores. The stability evaluation scores are used to quantify the stability of charging of photovoltaic cells in the floating charging stage; the effectiveness evaluation index acquisition module is used to monitor the key information data of photovoltaic cells in the energy storage management process in real time if an energy storage management strategy is formulated, and monitor the changes of key information data in the floating charging stage in real time to obtain effectiveness evaluation indicators. The effectiveness evaluation indicators are used to reflect the effectiveness of the energy storage management strategy and the efficiency of energy storage management; the electric energy storage module is used to determine whether charging is completed based on the obtained effectiveness evaluation indicators. If so, the electric energy of the photovoltaic cell after charging is stored; otherwise, the energy storage management strategy is adjusted and the charging process of the photovoltaic cell continues to be monitored.

[0079] In this embodiment, when the obtained effectiveness evaluation index is greater than the preset effectiveness evaluation index, it is determined that charging is completed, otherwise a prompt message is sent through the communication interface to prompt the preset personnel to adjust the energy storage management strategy, such as adding heat dissipation equipment; wherein the preset effectiveness evaluation index is represented by the sum and average of the historical effectiveness evaluation indicators of the photovoltaic cells in the database for floating charging under the historical energy storage management strategy.

[0080] It should be noted that when the battery DMS receives an instruction that the obtained effectiveness evaluation index is not greater than the preset effectiveness evaluation index, the battery DMS can automatically stop the charging process of the photovoltaic battery and continue charging after the energy storage management strategy is adjusted, thereby achieving a more accurate evaluation and optimization of the effectiveness of photovoltaic battery charging during the implementation of the energy storage management strategy, thereby achieving an improvement in the charging efficiency of the photovoltaic battery and the effectiveness of the energy storage management strategy.

[0081] The embodiment of the present application provides an apparatus for applying a charging control and energy storage management method based on a photovoltaic cell, including: a voltage sensor, a current sensor, a temperature sensor, a light intensity sensor, a memory and a processor; the voltage sensor is used to obtain the actual voltage and floating charge voltage of the photovoltaic cell during the charging process; the current sensor is used to obtain the actual current and floating charge current of the photovoltaic cell during the charging process; the temperature sensor is used to obtain the actual temperature of the photovoltaic cell surface during the charging process; the light intensity sensor is used to obtain the actual light intensity on the photovoltaic cell surface during the charging process; the memory is used to store the obtained full charge status evaluation value, stability evaluation score, effectiveness evaluation index and the electric energy after the photovoltaic cell is charged; the processor is used to pre-process the battery status information sent by the battery BMS (such as data cleaning, data deduplication, and data smoothing).

[0082] To summarize, the embodiment of the present application monitors the changes in battery status information during the charging stage in real time to obtain a full charge status evaluation value, and dynamically adjusts the charging parameters of the photovoltaic battery based on the obtained full charge status evaluation value, and then determines whether to formulate an energy storage management strategy based on the obtained stability evaluation score, and finally monitors the changes in key information data during the floating charge stage in real time to obtain an effectiveness evaluation index, and at the same time determines whether the charging is completed based on the obtained effectiveness evaluation index, thereby achieving precise control of the photovoltaic battery charging process, and further improving the reliability of photovoltaic battery energy storage management, and effectively solving the problem of low correlation between photovoltaic batteries and the floating charge state during the energy storage management process in the prior art.

[0083] It will be appreciated by those skilled in the art that embodiments of the present invention may be provided as methods, systems, or computer program products. Therefore, the present invention may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Furthermore, the present invention may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0084] The present invention is described with reference to flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to embodiments of the present invention. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1A device that provides the functions specified in a block or multiple blocks.

[0085] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0086] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0087] Although the preferred embodiments of the present invention have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0088] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A charging control and energy storage management method based on photovoltaic cells, characterized in that: The following steps are involved: Step 1: read the battery status information sent by the battery BMS through the communication interface, and monitor the changes of the battery status information in the charging stage in real time to obtain a full charge status evaluation value, which is used to evaluate the matching degree between the photovoltaic battery and the floating charge mode during the current charging process; Step 2: dynamically adjust the charging parameters of the photovoltaic battery based on the acquired full charge state evaluation value, monitor the charging process of the photovoltaic battery in the floating charge stage in real time according to the dynamically adjusted charging parameters to obtain a stability evaluation score, and determine whether to formulate an energy storage management strategy based on the acquired stability evaluation score. The stability evaluation score is used to quantify the stability of the charging of the photovoltaic battery in the floating charge stage; Step 3: If an energy storage management strategy is formulated, the key information data of the photovoltaic battery in the energy storage management process is monitored in real time, and the changes of the key information data in the floating charge stage are monitored in real time to obtain effectiveness evaluation indicators, which are used to reflect the effectiveness of the energy storage management strategy and the efficiency of energy storage management; Step 4: determine whether charging is completed based on the obtained effectiveness evaluation index. If so, store the electric energy of the photovoltaic battery after charging; otherwise, adjust the energy storage management strategy and continue to monitor the charging process of the photovoltaic battery.

2. The photovoltaic cell-based charging control and energy storage management method according to claim 1, characterized in that: The battery status information includes voltage, current, temperature, internal resistance and remaining capacity; The charging stage includes a pre-charging stage, a constant current charging stage, a constant voltage charging stage and a floating charging stage; The key information data includes charging time, charging amount, and the first duty cycle and the second duty cycle in the floating charging stage; The first duty cycle represents the ratio of the total duration of the photovoltaic inverter providing charging current to the photovoltaic cell to the total duration of the floating charge stage; The second duty cycle represents the ratio of the total duration of the photovoltaic inverter stopping providing charging current to the photovoltaic cell to the total duration of the floating charge stage.

3. The charging control and energy storage management method based on photovoltaic cells as claimed in claim 1, characterized in that: The full charge state evaluation value is obtained by the following method: Counting the initial charging parameters of the photovoltaic cell at the beginning of a preset charging period and obtaining the actual charging parameters of the photovoltaic cell after the preset charging period, and obtaining the temperature deviation, voltage deviation, current deviation and power deviation accordingly, wherein the initial charging parameters include initial temperature, initial voltage, initial current and initial power, and the actual charging parameters include actual temperature, actual voltage, actual current and actual power; According to the actual light intensity of the photovoltaic cell in the preset charging period, the full charge state evaluation value is obtained in combination with the reference temperature deviation, reference voltage deviation, reference current deviation, reference power deviation and maximum allowable light intensity in the database; The temperature deviation is the difference between the actual temperature and the initial temperature; The voltage deviation is the difference between the actual voltage and the initial voltage; The current deviation is the difference between the actual current and the initial current; The power deviation is the difference between the actual power and the initial power.

4. The photovoltaic cell-based charging control and energy storage management method according to claim 1, characterized in that: The specific steps of dynamically regulating the charging parameters of the photovoltaic battery based on the acquired full charge state evaluation value include: E1, determine whether the obtained full charge state evaluation value is not less than the preset full charge state evaluation value, if so, enter the floating charge mode, otherwise execute E2; E2, if the charging process of the photovoltaic battery is in the constant current charging stage, the preset personnel are prompted to increase the charging voltage through the communication interface to speed up the charging speed; if the charging process of the photovoltaic battery is in the constant voltage charging stage, the preset personnel are prompted to increase the charging current through the communication interface to speed up the charging speed; E3, continue to monitor the charging process of the photovoltaic battery within the preset charging period according to the dynamically adjusted charging parameters.

5. The photovoltaic cell-based charging control and energy storage management method according to claim 1, characterized in that: The stability evaluation score is obtained by the following method: Real-time monitoring of the changes in the floating charge voltage and floating charge current of the photovoltaic cell during the floating charge stage to obtain the extreme values ​​of the floating charge parameters, and at the same time obtaining the average floating charge voltage and average floating charge current of the photovoltaic cell at the end of the floating charge stage, wherein the extreme values ​​of the floating charge parameters include the maximum floating charge voltage, the maximum floating charge current, the minimum floating charge voltage and the minimum floating charge current; The duration of the extreme values ​​of the floating charge parameters in the floating charge stage is counted respectively to obtain the floating charge parameter duration ratio, and the obtained average floating charge voltage and average floating charge current are combined to obtain a stability assessment score. The floating charge parameter duration ratio includes a first ratio, a second ratio, a third ratio and a fourth ratio.

6. The photovoltaic cell-based charging control and energy storage management method according to claim 1, characterized in that: The specific process of determining whether to formulate an energy storage management strategy based on the obtained stability evaluation score is as follows: Determine whether the obtained stability assessment score is within the stability assessment threshold range: If the obtained stability assessment score is within the stability assessment threshold range, an energy storage management strategy is formulated; If the obtained stability assessment score is not within the stability assessment threshold range, the energy storage management strategy is not formulated and the floating charge parameters are not adjusted. The floating charge process is continued according to the adjusted floating charge parameters and the stability assessment score is re-obtained until the re-obtained stability assessment score is within the stability assessment threshold range; The energy storage management strategy includes temperature control and capacity control; The temperature control means that a warning signal is issued when the actual temperature of the photovoltaic cell surface reaches the maximum allowable temperature; The capacity control indicates that a warning signal is issued when the remaining capacity of the photovoltaic cell is 0; The floating charge parameters include a floating charge period and a temperature compensation coefficient.

7. The photovoltaic cell-based charging control and energy storage management method according to claim 1, characterized in that: The specific steps for obtaining the effectiveness evaluation index are as follows: Counting the first duty cycle and the second duty cycle of the photovoltaic cell at the end of the preset floating charge period, and obtaining the first duty cycle coefficient and the second duty cycle coefficient in combination with the reference first duty cycle and the reference second duty cycle in the database; The floating charge capacity and total floating charge duration of the photovoltaic battery in the floating charge stage are counted, and the floating charge capacity coefficient and the total floating charge duration coefficient are obtained by combining the reference floating charge capacity and the reference total floating charge duration in the database, and the effectiveness evaluation index is obtained by combining the obtained stability evaluation score; The first duty cycle coefficient is obtained by processing the stability evaluation score, the first duty cycle and the reference first duty cycle; The second duty cycle coefficient is obtained by processing the stability evaluation score, the second duty cycle and the reference second duty cycle; The floating charge capacity coefficient is obtained by processing the floating charge capacity and the reference floating charge capacity; The total float charge duration coefficient is obtained by processing the total float charge duration and the reference total float charge duration.

8. The photovoltaic cell-based charging control and energy storage management method according to claim 7, characterized in that: The specific limiting expression of the effectiveness evaluation index is: ； In the formula, e is a natural constant, It represents the effectiveness evaluation index of the photovoltaic battery corresponding to the floating charging process when performing energy storage management. Indicates the stability evaluation score of the photovoltaic cell during floating charge. Indicates the floating charge capacity coefficient of the photovoltaic cell at the end of the preset floating charge period. Indicates the total float charge duration coefficient of the photovoltaic battery at the end of the preset float charge period. Indicates the first duty cycle coefficient of the photovoltaic cell at the end of the preset floating charge period, Indicates the second duty cycle coefficient of the photovoltaic cell at the end of the preset floating charge period.

9. Charging control and energy storage management system based on photovoltaic cells, characterized in that: include: A full charge state evaluation value acquisition module, a stability evaluation score acquisition module, a validity evaluation index acquisition module and an electric energy storage module; The full charge state evaluation value acquisition module is used to read the battery state information sent by the battery BMS through the communication interface, and monitor the change of the battery state information in the charging stage in real time to obtain the full charge state evaluation value, which is used to evaluate the matching degree between the photovoltaic cell and the floating charge mode during the current charging process; The stability evaluation score acquisition module is used to dynamically adjust the charging parameters of the photovoltaic battery based on the acquired full charge state evaluation value, and monitor the charging process of the photovoltaic battery in the floating charge stage in real time according to the dynamically adjusted charging parameters to obtain the stability evaluation score, and at the same time, determine whether to formulate an energy storage management strategy based on the acquired stability evaluation score. The stability evaluation score is used to quantify the stability of the charging of the photovoltaic battery in the floating charge stage; The effectiveness evaluation index acquisition module is used to monitor the key information data of the photovoltaic battery in the energy storage management process in real time if the energy storage management strategy is formulated, and to monitor the changes of the key information data in the floating charge stage in real time to obtain the effectiveness evaluation index, which is used to reflect the effectiveness of the energy storage management strategy and the efficiency of the energy storage management; The electric energy storage module is used to determine whether charging is completed based on the obtained effectiveness evaluation index. If so, the electric energy of the photovoltaic battery after charging is stored; otherwise, the energy storage management strategy is adjusted and the charging process of the photovoltaic battery is continuously monitored.

10. A device using the photovoltaic cell-based charging control and energy storage management method as described in any one of claims 1 to 8, characterized in that: include: Voltage sensor, current sensor, temperature sensor, light intensity sensor, memory and processor; The voltage sensor is used to obtain the actual voltage and floating charge voltage of the photovoltaic cell during the charging process; The current sensor is used to obtain the actual current and floating charge current of the photovoltaic cell during the charging process; The temperature sensor is used to obtain the actual temperature of the photovoltaic cell surface during charging; The light intensity sensor is used to obtain the actual light intensity on the surface of the photovoltaic cell during the charging process; The memory is used to store the acquired full charge state evaluation value, stability evaluation score, effectiveness evaluation index and the electric energy after the photovoltaic battery is fully charged; The processor is used to pre-process the battery status information sent by the battery BMS.

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