Power regulation method and device of photovoltaic energy storage system, electronic equipment and storage medium

Abstract

This application belongs to the field of photovoltaic energy storage technology, and relates to a power regulation method, device, electronic equipment, and storage medium for a photovoltaic energy storage system. By executing a baseline ratio calculation process based on a preset target battery current value until preset conditions are met, the baseline ratio calculation process includes: obtaining the load active power and the target total input power; obtaining a baseline ratio based on the load active power and the target total input power; obtaining a fine-tuning ratio based on a preset fine-tuning ratio calculation strategy; obtaining a control ratio based on the baseline ratio and the fine-tuning ratio; obtaining the target charging power of the photovoltaic energy storage system based on the load active power and the control ratio; and allocating the target charging power based on a preset priority allocation strategy. Based on this, the overall efficiency of dynamic energy allocation is improved through a two-layer calculation mechanism of baseline ratio and fine-tuning ratio, significantly reducing battery loss and completely avoiding curtailment.

Description

Technical Field

[0001] This application belongs to the field of photovoltaic energy storage technology, specifically relating to a power regulation method, device, electronic equipment and storage medium for a photovoltaic energy storage system. Background Technology

[0002] With the acceleration of the global energy transition, the penetration rate of renewable energy, especially photovoltaic (PV) power generation, in smart grids continues to increase. As a key component coordinating energy production, storage, and consumption, the operational efficiency and energy utilization rate of PV energy storage systems are receiving increasing attention. In such systems, PV arrays, energy storage batteries, and grid loads together constitute the core structure of energy flow. However, once the batteries are fully charged, the system often struggles to effectively handle the continuous input of PV power, leading to the waste of some clean energy. This not only reduces the overall economic efficiency of the system but also hinders the efficient integration and utilization of renewable energy. Given the high proportion of renewable energy connected to the grid, further improving the energy dispatch flexibility of PV-storage systems and avoiding energy waste has become a key technological focus for the industry.

[0003] In the process of developing this application, the inventors discovered that the prior art has at least the following problems: existing energy management strategies are usually unable to achieve efficient transfer and utilization of photovoltaic power under fully charged battery conditions, the system has limited ability to cope with complex operating conditions, and the overall efficiency in the dynamic energy allocation process still needs to be improved, especially in responding to real-time load changes and coordinating multiple energy sources. Summary of the Invention

[0004] To address the aforementioned issues, this application provides a power regulation method for a photovoltaic energy storage system that can dynamically match the load and has a rapid response capability without adding any hardware circuitry.

[0005] To address the aforementioned technical problems, one technical solution adopted in this application is: providing a power regulation method for a photovoltaic energy storage system. The method includes: executing a baseline ratio calculation process based on a preset target battery current value until a preset condition is met. The baseline ratio calculation process includes: obtaining the load active power and the target total input power; obtaining a baseline ratio based on the load active power and the target total input power; obtaining a fine-tuning ratio based on a preset fine-tuning ratio calculation strategy; obtaining a control ratio based on the baseline ratio and the fine-tuning ratio; obtaining the target charging power of the photovoltaic energy storage system based on the load active power and the control ratio; and allocating power to the target charging power based on a preset priority allocation strategy.

[0006] In some embodiments, the benchmark ratio calculation process includes: obtaining the load active power and the target total input power; and obtaining the benchmark ratio based on the load active power and the target total input power, including: obtaining the load active power, the energy storage battery current value, and the energy storage battery voltage value in the current cycle; obtaining the target total input power of the previous cycle in the current cycle; obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and the energy storage battery voltage value; and obtaining the benchmark ratio based on the total input power adjustment value, the target total input power, and the load active power.

[0007] In some embodiments, obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and the energy storage battery voltage value includes: obtaining a preset adjustment coefficient; and calculating the total input power adjustment value for the current cycle based on the target battery current value, the energy storage battery current value, the energy storage battery voltage value, and the adjustment coefficient.

[0008] In some embodiments, obtaining a reference ratio based on the total input power adjustment value, the target total input power, and the load active power includes: obtaining a preset initial reference ratio value; calculating the reference ratio for the current cycle based on the initial reference ratio value, the load active power, the target total input power, and the total input power adjustment value; calculating the total charging power for the current cycle based on the load active power and the reference ratio, and using the total charging power as the target total input power for the next cycle.

[0009] In some embodiments, obtaining the fine-tuning ratio based on a preset fine-tuning ratio calculation strategy includes: acquiring preset target parameters; the target parameters include a reference voltage value and a reference battery state of charge value; acquiring the energy storage battery voltage value, the energy storage battery state of charge value, and the energy storage battery current value in the current cycle; calculating the voltage difference based on the energy storage battery voltage value and the reference voltage value; setting the voltage difference to zero if the voltage difference is not greater than a preset threshold; calculating the voltage loop fine-tuning ratio based on the voltage difference if the voltage difference is greater than the preset threshold; calculating the current difference based on the energy storage battery state of charge value, the reference battery state of charge value, and the energy storage battery current value, and calculating the current loop fine-tuning ratio based on the current difference; judging the voltage loop fine-tuning ratio and the current loop fine-tuning ratio; using the voltage loop fine-tuning ratio as the fine-tuning ratio if the voltage loop fine-tuning ratio is greater than the current loop fine-tuning ratio; and using the current loop fine-tuning ratio as the fine-tuning ratio if the voltage loop fine-tuning ratio is not greater than the current loop fine-tuning ratio.

[0010] In some embodiments, the target parameters further include a current proportional coefficient and a current integral coefficient. Based on the energy storage battery's state of charge (SOC), a reference battery's SOC, and the energy storage battery's current value, a current difference is calculated, and a current loop fine-tuning calculation is performed based on this current difference to obtain the current loop fine-tuning ratio. This includes: obtaining the battery SOC difference based on the reference battery's SOC and the energy storage battery's SOC; converting the battery SOC difference into a current reference value using the current proportional coefficient; obtaining the current difference based on the current reference value and the energy storage battery's current value; and calculating the current loop fine-tuning ratio based on the current integral coefficient and the current difference.

[0011] In some embodiments, the target charging power includes target photovoltaic power, target grid power, and target battery power. Based on a preset priority allocation strategy, the target charging power is allocated as follows: when the target photovoltaic power fully compensates for the load's active power and power loss, the target charging power is allocated to the target photovoltaic power; when the target photovoltaic power is insufficient to compensate for the load's active power and the grid is online, the target charging power is allocated to both the target photovoltaic power and the target grid power; when the target photovoltaic power is insufficient to compensate for the load's active power and the grid is offline, the target charging power is allocated to both the target photovoltaic power and the target battery power.

[0012] To address the aforementioned technical problems, another technical solution adopted in this application is: providing a power regulation device for a photovoltaic energy storage system. The device includes: a reference ratio acquisition module, which executes a reference ratio calculation process based on a preset target battery current value until a preset condition is met. The reference ratio calculation process includes: acquiring the load active power and the target total input power; obtaining a reference ratio based on the load active power and the target total input power; a fine-tuning ratio acquisition module, which obtains a fine-tuning ratio based on a preset fine-tuning ratio calculation strategy; a control ratio acquisition module, which obtains a control ratio based on the reference ratio and the fine-tuning ratio; a target charging power acquisition module, which obtains the target charging power of the photovoltaic energy storage system based on the load active power and the control ratio; and a power allocation module, which allocates power to the target charging power based on a preset priority allocation strategy.

[0013] To solve the above-mentioned technical problems, another technical solution adopted in the embodiments of this application is: to provide an electronic device, including: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the above-mentioned method.

[0014] To solve the above-mentioned technical problems, another technical solution adopted in the embodiments of this application is: to provide a non-volatile computer-readable storage medium that stores computer-executable instructions, which, when executed by an electronic device, cause the electronic device to perform the above-mentioned method.

[0015] Unlike related technologies, this application provides a power regulation method, device, electronic equipment, and storage medium for a photovoltaic energy storage system. By executing a baseline ratio calculation process based on a preset target battery current value until preset conditions are met, the baseline ratio calculation process includes: obtaining the load active power and the target total input power; obtaining a baseline ratio based on the load active power and the target total input power; obtaining a fine-tuning ratio based on a preset fine-tuning ratio calculation strategy; obtaining a control ratio based on the baseline ratio and the fine-tuning ratio; obtaining the target charging power of the photovoltaic energy storage system based on the load active power and the control ratio; and allocating the target charging power based on a preset priority allocation strategy. Based on this, by accurately calculating the optimal matching relationship between input and output power through the control ratio, the overall efficiency of dynamic energy allocation is significantly improved, enabling the battery to maintain a near-zero current state for a long period, significantly reducing battery loss and completely avoiding curtailment. Furthermore, it possesses multi-source coordination and adaptive capabilities, allowing seamless switching of power supply paths according to operating conditions, comprehensively improving the economy, operating efficiency, and reliability of the photovoltaic energy storage system. Attached Figure Description

[0016] One or more embodiments are illustrated by way of example with reference to the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements having the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0017] Figure 1 This is a schematic diagram illustrating an application scenario of a power regulation method for a photovoltaic energy storage system provided in an embodiment of this application;

[0018] Figure 2 This is a flowchart of a power regulation method for a photovoltaic energy storage system provided in an embodiment of this application;

[0019] Figure 3 This is a flowchart illustrating a fine-tuning ratio calculation process provided in an embodiment of this application;

[0020] Figure 4 This is a schematic diagram of the structure of a power regulation device for a photovoltaic energy storage system provided in an embodiment of this application;

[0021] Figure 5 This is a schematic diagram of the hardware structure of an electronic device for performing a power regulation method of a photovoltaic energy storage system, provided in an embodiment of this application. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and thoroughly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0023] It should be noted that, unless otherwise specified, the various features in the embodiments of this application can be combined with each other, all of which are within the protection scope of this application. Furthermore, although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device schematic diagram or the order in the flowchart.

[0024] When an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements between them.

[0025] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of this application.

[0026] As the proportion of renewable energy in the global energy mix continues to increase, the large-scale application of photovoltaic (PV) power generation systems in smart grids has become one of the core directions of energy transition. As a key infrastructure coordinating PV production, energy storage, and load consumption, the operating efficiency of PV energy storage systems directly affects the utilization rate of renewable energy and the economics of the system. In a typical PV energy storage system, the PV array, energy storage batteries, and load together constitute the main energy flow link. However, when the energy storage unit is fully charged, the system often struggles to effectively absorb the continuously generated PV power, forcing the abandonment of some clean energy, resulting not only in resource waste but also limiting the improvement of the overall system performance.

[0027] In the process of realizing this application, the inventors found that the prior art has at least the following problems: (1) Insufficient energy dispatch flexibility: Traditional control strategies simplify photovoltaic power to a binary choice of "battery charging" or "curtailment", lacking the ability to dynamically adjust the power at the load end. When the battery is fully charged, even if the load has the capacity to absorb it, the system cannot directly route the surplus photovoltaic power to the load, resulting in the waste of photovoltaic power. (2) Low overall system efficiency: Curtailment is accompanied by multiple efficiency losses: the photovoltaic module's power generation efficiency decreases due to exiting the maximum power point tracking (MPPT) state, and the power electronic equipment also has inherent losses in the energy conversion process. (3) Lagging control strategy: Existing solutions mostly adopt threshold-based trigger curtailment control, which cannot achieve real-time coordinated optimization of battery status, load demand and photovoltaic output, especially in scenarios with frequent light fluctuations and load changes. (4) Lack of multi-energy coordination mechanism: In distributed photovoltaic and energy storage applications, the system often does not have the ability to optimize and allocate power flow between photovoltaic, grid and battery in real time, making it difficult to achieve aggregated control of clustered load resources.

[0028] To address the aforementioned shortcomings, this application aims to solve the problem of how to achieve dynamic and precise matching of photovoltaic, grid, and battery power in a photovoltaic energy storage system through a pure software control strategy without increasing hardware complexity. This will maximize the utilization of photovoltaic power under full battery charging conditions, avoid energy waste, maintain the battery in a healthy state with near-zero current, extend battery life, and improve the overall operating efficiency and economy of the system under multiple operating conditions.

[0029] To address this, this application proposes a power regulation method for photovoltaic energy storage systems based on a dynamic scaling factor. The core of this method lies in constructing an adaptive matching relationship between input and output power through a real-time algorithm, replacing the traditional rigid threshold control strategy. The specific technical concept is as follows:

[0030] (1) Establish a dynamic power matching model: Introduce a dynamic proportional factor as a real-time representation of system efficiency. Through the core relationship of target charging power = load active power / control ratio, dynamically calculate the required input power to offset efficiency loss and fluctuation under different operating conditions.

[0031] (2) Design of a dual-loop structure of reference ratio and fine-tuning ratio: The reference ratio is estimated in real time through the partial derivative formula of the system power balance relationship to achieve rapid power feedforward adjustment; the fine-tuning ratio is generated by the battery voltage and the SOC dual-loop PI controller, and the steady-state error is eliminated by slow integration, so as to ensure that the battery current is stable near zero.

[0032] (3) Set a multi-energy priority allocation strategy: Based on the principle of "photovoltaic priority, grid priority, and battery supplementation", power is allocated in real time according to the source and load status: when photovoltaic is sufficient, all loads are powered by photovoltaic; when photovoltaic is insufficient, it is supplemented by grid; when grid is unavailable, the battery provides the difference in power.

[0033] (4) Achieve battery protection and efficient energy utilization: By maintaining the battery in a non-charging and non-discharging state under full charge, the cycle consumption of battery power is significantly reduced, avoiding the life loss caused by frequent charging based on SOC hysteresis in the traditional method, and completely eliminating the phenomenon of light abandonment.

[0034] Please see Figure 1 , Figure 1 This is a schematic diagram illustrating an application scenario of a power regulation method for a photovoltaic energy storage system provided in an embodiment of this application. For example... Figure 1 As shown, the photovoltaic energy storage system 100 is an intelligent energy system integrating photovoltaic power generation, energy storage, grid interaction, and load power supply functions. It aims to achieve efficient utilization of renewable energy, stable power supply, and economical system operation. This system is particularly suitable for scenarios with high requirements for energy autonomy, economy, and reliability. Its core application value lies in its ability to dynamically coordinate multiple energy sources, maximizing the consumption of photovoltaic power while ensuring battery health and avoiding energy waste. Specifically, the photovoltaic energy storage system 100 includes a photovoltaic source 10, an energy storage device 20, a grid 30, and a load 40. The energy storage device 20 is connected to the photovoltaic source 10, the grid 30, and the load 40.

[0035] In this embodiment, photovoltaic source 10 refers to a photovoltaic power generation array composed of photovoltaic modules, used to convert solar energy into direct current (DC) electricity. Photovoltaic source 10 serves as the main renewable energy generation unit of the photovoltaic energy storage system 100, and its power generation varies with sunlight intensity. It is the system's priority energy source, designed to power the load and charge the energy storage device, reducing dependence on the power grid and electricity costs.

[0036] Energy storage device 20 typically refers to a lithium-ion battery pack and its associated battery management system (BMS) and power conversion system (PCS). As an energy buffer and storage unit of the system, the core function of energy storage device 20 is to achieve time-shifting of energy. It stores electrical energy when photovoltaic power generation is excessive and releases it when photovoltaic power generation is insufficient or load demand is high, thereby smoothing power fluctuations, improving energy self-sufficiency, and serving as a backup power source during grid outages. In this embodiment, the provided power regulation method also maintains the battery in a near-zero current "standby" state after it is fully charged, greatly reducing ineffective charge-discharge cycles and effectively extending its service life.

[0037] Grid 30 refers to the public AC power grid connected to the photovoltaic energy storage system 100. Grid 30 serves as the system's auxiliary energy source and backup support. When photovoltaic power generation cannot meet load demand, the grid can supply power to the load or charge the energy storage device on demand; conversely, when photovoltaic power generation is excessive and energy storage is full, some systems can also choose to feed excess power into the grid (if the grid connection agreement allows). In this embodiment, it is used as a secondary power supplement source besides photovoltaics to optimize the economic operation of the system.

[0038] Load 40 refers to all electrical devices powered by the photovoltaic energy storage system 100, including DC and AC loads, serving as the system's terminal power consumption units. In this embodiment, by matching the load's demand, the power output of photovoltaic, energy storage, and the power grid is intelligently scheduled to ensure the continuity and stability of the load's power supply.

[0039] The implementation process of the power regulation method of the photovoltaic energy storage system provided in this application embodiment will be described in detail below with reference to specific embodiments.

[0040] Please see Figure 2 , Figure 2 This is a flowchart illustrating a power regulation method for a photovoltaic energy storage system provided in an embodiment of this application. Figure 2 As shown, the method includes steps S11-S15:

[0041] S11: Based on the preset target battery current value, execute the benchmark ratio calculation process until the preset conditions are met. The benchmark ratio calculation process includes: obtaining the load active power and the target total input power; and obtaining the benchmark ratio based on the load active power and the target total input power.

[0042] The benchmark ratio calculation process includes: obtaining the load active power and the target total input power; obtaining the benchmark ratio based on the load active power and the target total input power, including: obtaining the load active power, energy storage battery current value, and energy storage battery voltage value in the current cycle; obtaining the target total input power of the previous cycle in the current cycle; obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and energy storage battery voltage value; and obtaining the benchmark ratio based on the total input power adjustment value, the target total input power, and the load active power.

[0043] The process of obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and the energy storage battery voltage value includes: obtaining a preset adjustment coefficient; and calculating the total input power adjustment value for the current cycle based on the target battery current value, the energy storage battery current value, the energy storage battery voltage value, and the adjustment coefficient.

[0044] The process of obtaining a reference ratio based on the total input power adjustment value, the target total input power, and the load active power includes: obtaining a preset initial reference ratio value; calculating the reference ratio for the current cycle based on the initial reference ratio value, the load active power, the target total input power, and the total input power adjustment value; and calculating the total charging power for the current cycle based on the load active power and the reference ratio, and using the total charging power as the target total input power for the next cycle.

[0045] Specifically, an iterative algorithm is used to calculate the baseline ratio in real time. This value is a dynamic estimate of the system's overall efficiency, enabling the system to calculate the target charging power, thereby maximizing photovoltaic utilization and avoiding curtailment. Additionally, the battery is maintained in a near-zero current "standby" state to reduce losses and extend its lifespan. The process for obtaining the baseline ratio is as follows:

[0046] This process executes cyclically, in units of one control cycle:

[0047] (1) System initialization: preset initial reference ratio value (e.g., 0.92, the specific value can be set according to the actual situation); preset adjustment coefficient Used to control the magnitude of power adjustment; sets the target battery current value. Set the current to 0A; initialize the target total input power of the previous cycle. .

[0048] (2) Real-time data acquisition: At the beginning of each control cycle n, the system acquires the following data in real time: active power of the load. The actual power currently consumed by the load; the current value of the energy storage battery. Real-time current at the battery terminal; positive values ​​indicate charging, negative values ​​indicate discharging; energy storage battery voltage value. Real-time voltage at the battery terminal.

[0049] (3) Calculate the total input power adjustment value for the current cycle. The calculation formula is as follows:

[0050] ;

[0051] Understandable, Calculate the current error. If the battery is discharging ( A positive result indicates insufficient system input power, requiring increased power to cover load demands. This can be achieved by multiplying by... The current error is converted into a power error. Additionally, this is done by multiplying by an adjustment factor. This allows the adjustment mechanism to converge, making the system more stably approach the desired state.

[0052] (4) Iteratively update the baseline ratio, the specific process of which is as follows:

[0053] Based on the benchmark ratios provided above The calculation process shows that:

[0054] ;

[0055] Understandably, this calculation formula represents the baseline proportion in steady state. It is the ratio of the load's active power to the target total input power, which can be understood as the system's "energy efficiency ratio". In reality, the target total input power cannot be obtained accurately in real time (there is a delay or it needs to be calculated).

[0056] Therefore, in order to estimate the change of the reference ratio in real time, the partial derivative of the reference ratio with respect to the target total input power is taken, and the following is obtained:

[0057] ;

[0058] ;

[0059] To facilitate real-time calculations, use the current measured values. Compared to the previous cycle Substituting the values, we obtain the final formula for calculating the baseline ratio:

[0060] ;

[0061] in, The term originates from the partial derivative of efficiency with respect to power, and its physical meaning is the rate of change of efficiency caused by a unit change in power. It is a weighting factor that adjusts the total input power. This is converted into a correction to the efficiency estimate. (Summarization symbol) This is crucial; it represents the current cycle's efficiency estimate (baseline ratio). It is an adjustment value based on all historical periods. The result of cumulative calculation.

[0062] (5) Calculate the total charging power for the current cycle, update the historical data, and repeat the process. The formula for calculating the total charging power is as follows:

[0063] ;

[0064] Will Save as the target total input power for the next cycle. ,Right now Then, the process returns to step (2) and begins the next control cycle n+1 until the preset condition is met and the cycle terminates. The preset condition is that the absolute value of the difference between the target battery current value and the energy storage battery current is not greater than a preset empirical value (e.g., 2.5A).

[0065] It should be noted that during the power regulation process of photovoltaic energy storage systems, due to the inherent delays in sensor detection, signal transmission, and power device response, traditional proportional-integral (PI) control algorithms struggle to balance dynamic response speed and system stability. Specifically, the cumulative effect of the integral term can lead to excessive control commands under delayed conditions, causing system power oscillations or overshoot, thereby prolonging the adjustment time and even affecting the operational safety of the battery and conversion equipment.

[0066] To overcome the aforementioned shortcomings, this embodiment replaces the proportional control link in traditional PI control with an analytical formula based on efficiency partial derivatives, calculating the reference ratio in real time. This formula establishes a dynamic partial derivative relationship between the system output power and input power, constructing a feedforward power prediction mechanism. This mechanism can directly calculate the theoretical power adjustment (total input power adjustment value) required to most closely approximate the target battery current based on real-time collected load active power and battery status. This calculation method based on the analytical formula of efficiency partial derivatives has the following characteristics: First, it achieves rapid power regulation response, avoiding regulation delay caused by integral lag; second, feedforward prediction suppresses the oscillation trend caused by system inertia and signal delay, significantly improving the stability and convergence of regulation; third, it enhances the system's robustness to operating parameter delays and disturbances, providing a stable adjustment basis for subsequent fine-tuning, thereby improving the overall dynamic quality and energy utilization efficiency of photovoltaic-storage coordinated control.

[0067] In this embodiment, by introducing an analytical formula based on efficiency partial derivatives to replace the proportional element in traditional proportional-integral (PI) control, the dynamic control performance and operating efficiency of the photovoltaic energy storage system are significantly improved. This process enables rapid power feedforward adjustment even with sensor and actuator delays, effectively avoiding overshoot and oscillation problems caused by the accumulation of integral terms, thereby significantly enhancing system stability and convergence speed. By estimating and iteratively optimizing the baseline ratio in real time, this calculation process can accurately match input and output power, allowing the battery current to quickly approach zero current. This not only maintains the battery at an ideal non-charging / non-discharging operating point under various operating conditions, extending battery life, but also eliminates curtailment.

[0068] S12: Based on the preset fine-tuning ratio calculation strategy, the fine-tuning ratio is obtained.

[0069] The process involves obtaining the fine-tuning ratio based on a preset fine-tuning ratio calculation strategy, including: acquiring preset target parameters; the target parameters include a reference voltage value and a reference battery state of charge value; acquiring the energy storage battery voltage value, energy storage battery state of charge value, and energy storage battery current value in the current cycle; calculating the voltage difference based on the energy storage battery voltage value and the reference voltage value; setting the voltage difference to zero if it is not greater than a preset threshold; calculating the voltage loop fine-tuning ratio based on the voltage difference if it is greater than the preset threshold; calculating the current difference based on the energy storage battery state of charge value, the reference battery state of charge value, and the energy storage battery current value, and calculating the current loop fine-tuning ratio based on the current difference; judging the voltage loop fine-tuning ratio and the current loop fine-tuning ratio; using the voltage loop fine-tuning ratio as the fine-tuning ratio if it is greater than the current loop fine-tuning ratio; and using the current loop fine-tuning ratio as the fine-tuning ratio if it is not greater than the current loop fine-tuning ratio.

[0070] The target parameters include a current proportional coefficient and a current integral coefficient. Based on the energy storage battery's state of charge (SOC), a reference battery's SOC, and the energy storage battery's current, the current difference is calculated. A current loop fine-tuning calculation is then performed based on this current difference to obtain the current loop fine-tuning ratio. This process includes: obtaining the battery SOC difference based on the reference battery's SOC and the energy storage battery's SOC; converting the battery SOC difference into a current reference value using the current proportional coefficient; obtaining the current difference based on the current reference value and the energy storage battery's current; and calculating the current loop fine-tuning ratio based on the current integral coefficient and the current difference.

[0071] In step S11, during the iterative update of the reference ratio, if the absolute value of the difference between the target battery current and the energy storage battery current is not greater than a preset empirical value (e.g., 2.5A), it indicates that the obtained reference ratio already meets the ideal condition and no further update is needed. At this point, a fine-tuning ratio calculation strategy is used. This involves employing a parallel PI control structure with voltage and current (SoC) loops, using a feedforward-feedback composite control method to achieve high-precision compensation of the reference ratio. The core of this strategy is to eliminate steady-state errors through slow integration and achieve zero-current maintenance of the battery while ensuring system safety. (See also...) Figure 3 , Figure 3 This is a flowchart of a fine-tuning ratio calculation process provided in an embodiment of this application, and its specific implementation process is as follows:

[0072] (1) Definition of key parameters: Preset reference voltage value corresponding to the full charge state of the battery Reference battery state of charge value (Corresponding to full charge state, usually set to 1000‰); Voltage integral coefficient The core of slow integration; vibration damping / differential damping coefficient Current proportionality coefficient Used to convert SoC deviation into a current reference value; current integral coefficient The core of slow integration; vibration damping / differential damping coefficient It is used to suppress current measurement ripple or rapid disturbances, and its main function is still integration; limiting circuit Voltage dead zone threshold (Can be set according to actual conditions, for example, 0.5V); Output: Voltage loop fine-tuning ratio Current loop fine-tuning ratio Fine-tuning the ratio .

[0073] (2) Acquire real-time data: energy storage battery voltage value Energy storage battery state of charge value and the current value of the energy storage battery .

[0074] (3) Voltage loop calculation (slow integration with dead zone):

[0075] First, calculate the voltage difference. A dead zone is set, and its calculation formula is as follows:

[0076] ;

[0077] like If the value is within a small fluctuation range near full charge, the system considers it to be "without error" and sets it to... It stops moving, thus avoiding repeated fine-tuning and oscillations around the target value;

[0078] like Then the slow integral calculation process begins.

[0079] Secondly, when entering the slow integral calculation process, through and right The voltage loop fine-tuning ratio is obtained by performing slow integration. .

[0080] It should be noted that the output is immediately "frozen" once the voltage loop returns to the dead zone to ensure stability. The closed-loop time constant can be designed to be on the order of tens of seconds, thus avoiding conflict with the rapid adjustment of the reference ratio.

[0081] (4) Current loop calculation (zero current holding driven by SoC):

[0082] First, calculate the battery state-of-charge difference to obtain the current reference value. The calculation formula is as follows:

[0083] ;

[0084] in, The "thousandth percentile SoC error" is linearly mapped to the "current reference value". When the battery is full and a "neither charging nor discharging" state is desired, Close to the full charge threshold, therefore Approaching 0.

[0085] Secondly, the current difference is calculated. The calculation formula is as follows:

[0086] ;

[0087] The fine-tuning ratio is constructed primarily using integrals, through... and right The current loop fine-tuning ratio is calculated. .

[0088] It should be noted that the goal of the fine-tuning ratio calculation is to... By maintaining a preset empirical value (e.g., 2.5A) for an extended period, the current loop only needs to be "gradually corrected," avoiding conflict with the rapid power matching of the upper-level "reference ratio." Additionally, The value is slightly larger than that of the voltage loop. It is usually more appropriate to use current deviation as it is a more direct and controllable quantity, but it is still necessary to keep it "slow". It is not necessary; turning on a small amount of damping will make the system more stable when there is ripple or sudden change (such as load step).

[0089] (5) Comparison / selection and output:

[0090] First, regarding the obtained and The principle of choosing the larger value should be followed, that is: if ,but ,on the contrary .

[0091] Secondly, for By limiting the amplitude, we can obtain Understandably, this ensures that "stricter loop constraints" take precedence: when voltage fluctuations exceed the expected range, the voltage loop dominates; when the current deviates from the zero window, the current loop dominates, pulling the battery back to a "neither charging nor discharging" state.

[0092] In this embodiment, a fine-tuning proportional calculation method combining a battery voltage loop and a battery current loop is employed. This method allows for precise correction of the power allocation ratio based on rapid adjustment of the baseline ratio, utilizing the slow response characteristics of the PI loop integral. On one hand, the voltage loop sets the full-charge voltage as the target value and introduces a voltage dead zone detection mechanism. This ensures that the battery only outputs an adjustment signal when fluctuations exceed the expected range near full charge, thus avoiding unnecessary charge / discharge adjustments due to minor voltage fluctuations and effectively improving system stability. On the other hand, the current loop uses the battery's state of charge (SoC) and real-time current as references. Through proportional conversion and slow integral correction, it maintains the battery current within a near-zero window range, ensuring the battery operates in a non-charging / non-discharging state when fully charged, significantly extending battery life. Simultaneously, the fine-tuning ratios output from the voltage and current loops are superimposed on the baseline ratio after limiting and optimization processing, ensuring the adjustment amount remains within a reasonable range. This avoids over-correction issues caused by PI integral accumulation and maximizes the utilization of renewable energy when photovoltaic output is sufficient, preventing curtailment.

[0093] S13: Obtain the control ratio based on the baseline ratio and the fine-tuning ratio.

[0094] S14: Based on the load active power and control ratio, obtain the target charging power of the photovoltaic energy storage system.

[0095] The baseline ratio is calculated in steps S11 and S12. and fine-tuning ratio Next, the control ratio E and the amplitude limit are calculated, and the calculation formula is as follows:

[0096] ;

[0097] ;

[0098] The calculated control ratio E is a value between 0 and 1 (or between 0% and 100%), representing the conversion efficiency. Understandably, when the system begins control, a baseline ratio is obtained. After several cycles of adjustment, the error gradually decreases until a preset condition is reached. Then, a fine-tuning ratio is obtained, and the baseline ratio at the time the preset condition was reached is used. The two ratios are then combined to form the control ratio.

[0099] Subsequently, the target charging power is calculated using the following formula:

[0100] ;

[0101] The calculated target charging power represents the total power that needs to be input to the load from the photovoltaic source, the grid, and the battery side.

[0102] S15: Based on a preset priority allocation strategy, allocate power to the target charging power.

[0103] The target charging power includes target photovoltaic power, target grid power, and target battery power. Based on a preset priority allocation strategy, the target charging power is allocated as follows: when the target photovoltaic power fully compensates for the load's active power and power loss, the target charging power is allocated to the target photovoltaic power; when the target photovoltaic power is insufficient to compensate for the load's active power and the grid is online, the target charging power is allocated to both the target photovoltaic power and the target grid power; when the target photovoltaic power is insufficient to compensate for the load's active power and the grid is offline, the target charging power is allocated to both the target photovoltaic power and the target battery power.

[0104] After the target charging power is calculated, the target photovoltaic power is allocated based on a preset priority allocation strategy. ), target grid power ( ) and target battery power ( Dynamic allocation is performed. Unlike the traditional method that relies on battery SoC hysteresis to trigger charging, this embodiment introduces the allocation principle of "photovoltaic priority, grid second, and battery as a backup". It can keep the battery in a non-charging and non-discharging state for a long time when the input power is sufficient, thereby significantly extending the battery life, avoiding capacity decay caused by frequent charging and discharging, and realizing full utilization of photovoltaic power and reducing curtailment.

[0105] First, the current target charging power is calculated according to step S14. The formula for power allocation is as follows:

[0106] ;

[0107] in, , , These represent the target photovoltaic power, the target grid power, and the target battery power, respectively.

[0108] Secondly, based on the current power allocation requirements, and according to power supply priority and input source availability, an allocation strategy is executed. The specific process is as follows:

[0109] (1) When the target photovoltaic power fully compensates for the active power and loss power of the load, , , .

[0110] Understandably, at this point, the photovoltaic power completely covers the load-side demand and losses. The grid does not require input, the battery can remain in a state of neither charging nor discharging, and the power is also 0.

[0111] (2) When the target photovoltaic power is insufficient to compensate for the active power of the load, and the grid is online, , , .

[0112] Understandably, the system will first maximize the photovoltaic power (i.e., prioritize the use of the maximum available photovoltaic capacity). The remaining shortfall is replenished by the power grid, and the battery continues to remain neither charged nor discharged. The value is 0. It should be noted that, ideally, under the action of the battery management fine-tuning loop, if a slight power imbalance occurs, it will be distributed between the grid and photovoltaic through limiting and integral regulation, ensuring that the battery remains near zero power and does not trigger charging and discharging, thereby maximizing the extension of battery life.

[0113] (3) When the target photovoltaic power is insufficient to compensate for the active power of the load, and the grid is offline, , , .

[0114] Understandably, this is because the power grid is offline. This is also insufficient to cover the demand; batteries need to be involved to fill the power gap.

[0115] In addition, when the photovoltaic source is offline but the grid is online, the grid power compensates for part of the load power, and the remaining power is provided by the battery; when the photovoltaic source is offline and the grid is offline, the battery provides all the power.

[0116] This embodiment enables the rational allocation of power among photovoltaic (PV), grid, and battery components under different operating scenarios: When PV power is sufficient, the system prioritizes utilizing PV to cover loads and mitigate losses, keeping the battery in a non-charging / non-discharging state. This avoids shortening battery life due to frequent charging and discharging triggered by traditional hysteresis SoCs, while ensuring that PV power is not wasted. When PV is insufficient and the grid is online, the grid only supplements the difference, and the battery remains at zero power. Fine-tuning the ratio suppresses battery power fluctuations, further protecting battery life. When PV is insufficient and the grid is offline, the battery passively participates in compensating for the power shortfall. While ensuring the continuity of system power supply, the power allocation formula and ratio adjustment limit excessive discharge, thereby improving the stability and safety of system operation. Thus, it not only maximizes the utilization of PV power and improves the efficiency of renewable energy utilization, but also significantly extends battery life by reducing frequent battery cycling. Furthermore, it maintains reliable system operation even under extreme conditions such as grid failure, balancing economic efficiency, environmental friendliness, and power supply reliability.

[0117] This application proposes a power regulation method for a photovoltaic energy storage system by designing a software control method. This method enables flexible control of battery input and output power without adding any hardware circuitry. Through a two-layer calculation mechanism of a base ratio and a fine-tuning ratio, it achieves rapid power adjustment and precise compensation even when there is a delay in the information source, thus maintaining the battery in a near-zero current non-charging and non-discharging state for extended periods, significantly extending battery life. Simultaneously, it can flexibly allocate power under different operating conditions: when photovoltaic power is sufficient, photovoltaic power takes priority in bearing the load; when photovoltaic power is insufficient, it flexibly switches between grid or battery power to fill the gap depending on whether the grid is online, thereby ensuring stable power supply under various operating conditions. Compared to the traditional binary control method of forced "charging or curtailment," this method achieves dynamic power routing between photovoltaic, grid, and load, effectively avoiding photovoltaic curtailment and frequent charging and discharging problems triggered by hysteresis control. This not only improves the utilization rate of photovoltaic power generation and the overall system efficiency but also reduces efficiency losses caused by multiple energy conversions, further improving the system's economic efficiency and renewable energy absorption capacity. It is particularly suitable for efficient energy management in portable energy storage power supplies and high-proportion renewable energy grid-connected scenarios.

[0118] Based on the power regulation method for photovoltaic energy storage systems provided in the above embodiments, this application further provides a power regulation device for photovoltaic energy storage systems. Please refer to... Figure 4 , Figure 4 This is a schematic diagram of the power regulation device of the photovoltaic energy storage system. (For example...) Figure 4 As shown, the power regulation device 200 of the photovoltaic energy storage system includes: a reference ratio acquisition module 210, a fine-tuning ratio acquisition module 220, a control ratio acquisition module 230, a target charging power acquisition module 240, and a power distribution module 250.

[0119] The reference ratio acquisition module 210 is used to execute a reference ratio calculation process based on a preset target battery current value until a preset condition is met. The reference ratio calculation process includes: acquiring the load active power and the target total input power; obtaining the reference ratio based on the load active power and the target total input power; the fine-tuning ratio acquisition module 220 is used to obtain the fine-tuning ratio based on a preset fine-tuning ratio calculation strategy; the control ratio acquisition module 230 is used to obtain the control ratio based on the reference ratio and the fine-tuning ratio; the target charging power acquisition module 240 is used to obtain the target charging power of the photovoltaic energy storage system based on the load active power and the control ratio; and the power allocation module 250 is used to allocate the target charging power based on a preset priority allocation strategy.

[0120] It should be noted that the power regulation device of the photovoltaic energy storage system described above can execute the power regulation method of the photovoltaic energy storage system provided in the embodiments of this application, and has the corresponding functional modules and beneficial effects of the method. Technical details not described in detail in the embodiments of the power regulation device of the photovoltaic energy storage system can be found in the power regulation method of the photovoltaic energy storage system provided in the embodiments of this application.

[0121] This application also provides an electronic device 300, which may be an energy management unit (EMS). Please refer to [link to relevant documentation]. Figure 5 This diagram illustrates the hardware structure of an electronic device 300 capable of performing the methods described in the above embodiments. The electronic device 300 includes: at least one processor 310; and a memory 320 communicatively connected to the at least one processor 310. Figure 5 Taking a processor 310 as an example, the memory 320 stores instructions executable by the at least one processor 310. These instructions are executed by the at least one processor 310 to enable it to perform the power regulation method of the photovoltaic energy storage system described in the above embodiment. The processor 310 and the memory 320 can be connected via a bus or other means. Figure 5 Taking the example of a connection between China and Israel via a bus.

[0122] The memory 320, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the power regulation method of the photovoltaic energy storage system in the embodiments of this application. The processor 310 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions, and modules stored in the memory 320, thereby realizing the power regulation method of the photovoltaic energy storage system described in the above embodiments.

[0123] The memory 320 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the computing device. Furthermore, the memory 320 may include high-speed random access memory and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other non-volatile solid-state storage device. In some embodiments, the memory 320 may optionally include memory remotely located relative to the processor 310, and these remote memories may be connected to the computing device via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0124] The one or more modules are stored in the memory 320, and when executed by the one or more processors 310, they perform the power regulation method of the photovoltaic energy storage system described in the above embodiments.

[0125] The above-described products can perform the methods provided in the embodiments of this application, and possess the corresponding functional modules and beneficial effects for performing the methods. Technical details not described in detail in this embodiment can be found in the power regulation method of the photovoltaic energy storage system described in the embodiments of this application.

[0126] This application provides a non-volatile computer-readable storage medium storing computer-executable instructions. These instructions are executed by one or more processors to enable the at least one processor to perform the power regulation method of the photovoltaic energy storage system described in the above embodiments. For example, the non-volatile computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a compact disc read-only memory (CDROM), magnetic tape, floppy disk, or optical data storage device, etc.

[0127] It should be noted that the device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0128] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0129] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and not to limit them; under the concept of this application, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this application as described above, which are not provided in detail for the sake of brevity; although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A power regulation method for a photovoltaic energy storage system, characterized in that, The method includes: Based on a preset target battery current value, a baseline ratio calculation process is executed until a preset condition is met. The baseline ratio calculation process includes: in the current cycle, obtaining the load active power, the energy storage battery current value, and the energy storage battery voltage value; obtaining the target total input power of the previous cycle in the current cycle; obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and the energy storage battery voltage value; and obtaining the baseline ratio based on the total input power adjustment value, the target total input power, and the load active power. The fine-tuning ratio is obtained based on a preset fine-tuning ratio calculation strategy; wherein the fine-tuning ratio is calculated based on the parallel proportional-integral control structure of voltage loop and current loop. The control ratio is obtained based on the baseline ratio and the fine-tuning ratio; The target charging power of the photovoltaic energy storage system is obtained based on the load active power and the control ratio; wherein, the target charging power includes the target photovoltaic power, the target grid power, and the target battery power; Based on a preset priority allocation strategy, the target charging power is allocated.

2. The power regulation method for a photovoltaic energy storage system according to claim 1, characterized in that, The step of obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and the energy storage battery voltage value includes: Obtain the preset adjustment coefficient; The total input power adjustment value for the current cycle is calculated based on the target battery current value, the energy storage battery current value, the energy storage battery voltage value, and the adjustment coefficient.

3. The power regulation method for a photovoltaic energy storage system according to claim 1, characterized in that, The process of obtaining the baseline ratio based on the total input power adjustment value, the target total input power, and the load active power includes: Obtain the preset initial baseline ratio value; The reference ratio for the current cycle is calculated based on the initial reference ratio value, the load active power, the target total input power, and the total input power adjustment value. Based on the load active power and the reference ratio, the total charging power of the current cycle is calculated, and the total charging power is used as the target total input power for the next cycle of the current cycle.

4. The power regulation method for a photovoltaic energy storage system according to claim 1, characterized in that, The fine-tuning ratio is obtained based on a preset fine-tuning ratio calculation strategy, including: Obtain preset target parameters; the target parameters include a reference voltage value and a reference battery state of charge value; In the current cycle, the energy storage battery voltage value, the energy storage battery state of charge value, and the energy storage battery current value are obtained; Calculate the voltage difference based on the energy storage battery voltage value and the reference voltage value; If the voltage difference is not greater than a preset threshold, the voltage difference is set to zero; If the voltage difference is greater than the preset threshold, voltage loop fine-tuning calculation is performed based on the voltage difference to obtain the voltage loop fine-tuning ratio; Based on the state of charge value of the energy storage battery, the state of charge value of the reference battery, and the current value of the energy storage battery, the current difference is calculated, and the current loop fine-tuning is calculated based on the current difference to obtain the current loop fine-tuning ratio. The voltage loop fine-tuning ratio and the current loop fine-tuning ratio are determined. If the voltage loop fine-tuning ratio is greater than the current loop fine-tuning ratio, the voltage loop fine-tuning ratio shall be used as the fine-tuning ratio; If the voltage loop fine-tuning ratio is not greater than the current loop fine-tuning ratio, the current loop fine-tuning ratio shall be used as the fine-tuning ratio.

5. The power regulation method for a photovoltaic energy storage system according to claim 4, characterized in that, The target parameters also include the current proportional coefficient and the current integral coefficient. The step of calculating the current difference based on the energy storage battery's state of charge (SOC), the reference battery's SOC, and the energy storage battery's current, and then performing current loop fine-tuning calculations based on the current difference to obtain the current loop fine-tuning ratio, includes: The battery state of charge difference is obtained based on the reference battery state of charge value and the energy storage battery state of charge value. The battery state of charge difference is converted into a current reference value using the current proportionality coefficient; the current difference is obtained based on the current reference value and the energy storage battery current value. The current loop fine-tuning ratio is calculated based on the current integral coefficient and the current difference.

6. The power regulation method for a photovoltaic energy storage system according to claim 1, characterized in that, The power allocation to the target charging power based on a preset priority allocation strategy includes: When the target photovoltaic power fully compensates for the active power and loss power of the load, the target charging power is allocated to the target photovoltaic power; When the target photovoltaic power is insufficient to compensate for the active power of the load, and the grid is online, the target charging power is allocated to the target photovoltaic power and the target grid power. When the target photovoltaic power is insufficient to compensate for the active power of the load and the power grid is offline, the target charging power is allocated to the target photovoltaic power and the target battery power.

7. A power regulation device for a photovoltaic energy storage system, characterized in that, The device includes: A benchmark ratio acquisition module is used to execute a benchmark ratio calculation process based on a preset target battery current value until a preset condition is met. The benchmark ratio calculation process includes: acquiring the load active power, energy storage battery current value, and energy storage battery voltage value in the current cycle; acquiring the target total input power of the previous cycle in the current cycle; obtaining the total input power adjustment value for the current cycle based on the energy storage battery current value and the energy storage battery voltage value; and obtaining the benchmark ratio based on the total input power adjustment value, the target total input power, and the load active power. A fine-tuning ratio acquisition module is used to obtain a fine-tuning ratio based on a preset fine-tuning ratio calculation strategy; wherein the fine-tuning ratio is calculated based on a parallel proportional-integral control structure of voltage loop and current loop; A control ratio acquisition module is used to obtain a control ratio based on the reference ratio and the fine-tuning ratio. A target charging power acquisition module is used to obtain the target charging power of the photovoltaic energy storage system based on the load active power and the control ratio; wherein, the target charging power includes the target photovoltaic power, the target grid power, and the target battery power; A power allocation module is used to allocate power to the target charging power based on a preset priority allocation strategy.

8. An electronic device, characterized in that, include: At least one processor; as well as, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor to enable the at least one processor to perform the method according to any one of claims 1-6.

9. A non-volatile computer-readable storage medium, characterized in that, The non-volatile computer-readable storage medium stores computer-executable instructions that, when executed by an electronic device, cause the electronic device to perform the method described in any one of claims 1-6.

Images