Photovoltaic energy storage system charge-discharge control method based on dynamic threshold

Abstract

The application discloses a photovoltaic energy storage system charge-discharge control method based on a dynamic threshold, and relates to the technical field of photovoltaic energy storage, solves the technical problem that the shunt treatment and discharge control lack fine classification strategies when photovoltaic energy is excessive or insufficient, and energy waste or battery life attenuation is easily caused, the upper limit of the charging threshold is combined with the lower limit of the discharging threshold, the rated capacity of energy storage, and the charging and discharging efficiency is dynamically calculated, overcharging and overdischarging are avoided, the SOC-related charging and discharging limit function dynamically limits power according to real-time SOC, battery cycle loss is reduced, the service life is prolonged, the shunt treatment when photovoltaic energy is excessive adopts a hierarchical strategy of local adjustable load priority, grid-connected power selling, and limited power protection, key loads are ensured not to be affected by limited power, the discharge control when photovoltaic energy is insufficient distinguishes key loads from non-key loads, only triggers energy storage discharge for key loads, and non-key loads are cut off in advance through a warning threshold, discharge pressure is reduced, and power supply continuity is improved.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic energy storage technology, specifically to a charging and discharging control method for photovoltaic energy storage systems based on dynamic thresholds. Background Technology

[0002] Photovoltaic power generation is a method of generating electricity by converting solar energy into electrical energy. The electrical energy generated by the photovoltaic power generation system is stored in battery modules, which are then used to charge loads. Due to factors such as weather and the characteristics of sunlight itself, photovoltaic power generation is subject to strong fluctuations and randomness, resulting in relatively poor reliability.

[0003] According to patent announcement number CN117239868B, a method for controlling the charging and discharging of a photovoltaic energy storage system is disclosed, including the following steps: a charging and discharging detection unit measures the charging and discharging data of each battery in the battery module in real time; the charging and discharging data is stored in a data storage unit; an analysis and control unit extracts historical charging and discharging data from the data storage unit, and based on the historical charging and discharging data, uses a combination of machine learning algorithm model and filtering algorithm to estimate the charge amount and charge fluctuation value of each battery in the battery module within a preset time period, and controls the charging and discharging of each battery in real time.

[0004] However, traditional control methods use static charge and discharge thresholds, which cannot be dynamically adjusted according to the predicted trend of sunlight and the real-time fluctuations of photovoltaic / load. This leads to the energy storage being fully loaded and curtailed when there is excess photovoltaic power or prematurely discharged when there is insufficient photovoltaic power, reducing energy utilization. At the same time, the threshold adjustment is not deeply related to the sunlight trend and only depends on the current SOC state, resulting in insufficient utilization of energy storage capacity. The diversion and discharge control when there is excess or insufficient photovoltaic power lack a refined hierarchical strategy, which can easily lead to energy waste or battery life degradation. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a charging and discharging control method for photovoltaic energy storage systems based on dynamic thresholds. This method solves the problem of insufficient or excessive photovoltaic power generation and the lack of refined hierarchical strategies for current diversion and discharge control, which can easily lead to energy waste or battery life degradation.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds, which specifically includes the following steps:

[0007] Based on the load forecasting model and the short-term forecasting model, the predicted load and short-term photovoltaic output are obtained respectively, and the two values ​​are compared to generate a photovoltaic insufficiency or photovoltaic surplus analysis signal.

[0008] The photovoltaic excess analysis signal is processed to generate a signal to increase or decrease the charging threshold based on the change in the predicted future light intensity. At the same time, the upper limit of the charging threshold is calculated according to the formula and adjusted proportionally based on the change in the predicted future light intensity to obtain the charging adjustment threshold.

[0009] The system acquires the real-time state of charge and compares it with the charging adjustment threshold. If the latter is large, the charging power is determined according to the formula. If the latter is small, the energy storage system is diverted and charging adjustment information is generated.

[0010] The photovoltaic insufficiency analysis signal is processed to generate a signal to increase or decrease the discharge threshold based on the change in the predicted future light intensity. At the same time, the lower limit of the discharge threshold is calculated according to the formula and adjusted proportionally based on the change in the predicted future light intensity to obtain the discharge adjustment threshold.

[0011] The system acquires the real-time state of charge and compares it with the discharge adjustment threshold. If the latter is large, the system calculates the discharge power based on the load gap and energy storage safety constraints. If the latter is small, the system calculates the discharge power according to the formula and generates discharge adjustment information.

[0012] As a further aspect of the present invention, the specific method for generating the photovoltaic insufficiency or photovoltaic excess analysis signal is as follows:

[0013] Collect real-time photovoltaic power output, sunshine forecast, real-time load and historical data; build a load forecasting model based on historical data to obtain the predicted load; combine sunshine forecast to make short-term photovoltaic power output forecast.

[0014] By comparing short-term photovoltaic (PV) output with predicted load, a larger former indicates PV oversupply, generating an oversupply signal; a smaller former indicates PV undersupply, generating an undersupply signal.

[0015] As a further aspect of the present invention, the specific method for processing the photovoltaic excess analysis signal is as follows:

[0016] The generated photovoltaic excess analysis signal is processed, and the sunshine prediction data is analyzed. If the future sunshine prediction is strong, a signal to increase the charging threshold is generated; if the future sunshine prediction is weak, a signal to decrease the charging threshold is generated.

[0017] Obtain the rated energy storage capacity E of the photovoltaic energy storage system 额定 and real-time energy storage SOC 实时 At the same time, according to the formula The upper limit of the charging threshold SOC is calculated. max , where P PV预测 P represents the short-term photovoltaic output within the future Δt period. Load预测 This represents the predicted load within the future Δt, where η is the charge / discharge efficiency, based on the obtained upper limit of the charging threshold SOC. maxCalculate the adjustable charging threshold range, ΔSOC = SOC max -SOC 实时 Adjust according to the light prediction enhancement ratio. Similarly, calculate the charging adjustment threshold when the charging threshold decreases.

[0018] As a further aspect of the present invention, the specific method for determining the charging power according to the formula is as follows:

[0019] The system acquires real-time photovoltaic output and load power, along with real-time state of charge (SOC), and compares these with a charging adjustment threshold. If the real-time SOC is less than the charging adjustment threshold, charging control can continue. Then, according to formula P... ch =min(P PV实时 -P Load实时 P bat，max f(SOC)) is used to obtain the corresponding charging power P. ch And P ch The minimum charging power is P. bat，max The maximum allowable charging power of the energy storage battery is given by f(SOC), which is a charging power limitation function based on SOC. The charging power is adjusted according to SOC to generate charging regulation information.

[0020] As a further aspect of the present invention, the specific method for diverting the energy storage system is as follows:

[0021] If the real-time state of charge is greater than the charging adjustment threshold, it means that the energy storage system has reached the charging limit and needs to be diverted. If the system is equipped with local load adjustable resources, the excess power will be directed to the load first. If it is connected to the grid and has grid connection conditions, the excess power will be fed into the grid.

[0022] If local consumption and grid connection are both not feasible, the power limiting protection mechanism of the photovoltaic system is activated to reduce the output power of the photovoltaic inverter and generate charging regulation information.

[0023] As a further aspect of the present invention, the specific method for processing the photovoltaic insufficiency analysis signal is as follows:

[0024] Analyze illumination prediction data, generate signals to increase or decrease the discharge threshold based on future illumination predictions, and simultaneously apply the formula... The lower limit of discharge threshold SOC was calculated. max , where P PV预测 P represents the short-term photovoltaic output within the future Δt period. Load预测 This represents the predicted load within the future Δt, where η is the charging and discharging efficiency. Simultaneously, it is adjusted based on the generated signal to increase or decrease the discharge threshold, thus generating a discharge adjustment threshold.

[0025] As a further aspect of the present invention, the specific method for calculating the discharge power based on the load gap and energy storage safety constraints is as follows:

[0026] If the real-time state of charge is less than the discharge adjustment threshold, the discharge power is calculated based on the load gap and energy storage safety constraints, according to formula P. dis =min(P Load实时 -P PV实时 P bat，dis，max , g(SOC)), where P bat，dis，max For the maximum allowable discharge power of energy storage, g(SOC) represents the discharge limit function related to SOC, and is expressed as the calculated discharge power P. dis Discharge is performed according to the standard, generating discharge regulation information.

[0027] As a further aspect of the present invention, the specific method for calculating the discharge power according to the formula is as follows:

[0028] The system obtains real-time photovoltaic output and load power, acquires the corresponding real-time state of charge (SOC), and compares it with a discharge adjustment threshold. If the real-time SOC is greater than the discharge adjustment threshold, it indicates that discharge control can continue, according to formula P. dis =min(P Load实时 -P PV实时 P bat，max The corresponding discharge power P is obtained from f(SOC). dis The discharge is regulated based on the calculated discharge power, and discharge regulation information is generated simultaneously.

[0029] This invention provides a charging and discharging control method for photovoltaic energy storage systems based on dynamic thresholds. Compared with existing technologies, it has the following advantages:

[0030] This invention avoids overcharging and over-discharging by combining the upper limit of the charging threshold and the lower limit of the discharging threshold with the rated capacity of energy storage and the dynamic calculation of charging and discharging efficiency. The SOC-related charging and discharging limit function dynamically limits the power based on the real-time SOC, reducing battery cycle loss and extending service life. When there is excess photovoltaic power, the diversion treatment adopts a hierarchical strategy of prioritizing local adjustable loads, grid-connected power sales, and power limiting protection to ensure that critical loads are not affected by power limitations. When there is insufficient photovoltaic power, the discharge control distinguishes between critical and non-critical loads, triggering energy storage discharge only for critical loads, and cutting off non-critical loads in advance through early warning thresholds to reduce discharge pressure and improve power supply continuity. Attached Figure Description

[0031] Figure 1 This is a diagram illustrating the steps and methods of the present invention. Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] Please see Figure 1 This application provides a charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds, which specifically includes the following steps:

[0034] Step 1: Collect real-time photovoltaic output, solar irradiance prediction data, load power, and corresponding historical data of the photovoltaic energy storage system. Establish a corresponding load prediction model based on the historical data and obtain the corresponding predicted load. Then, perform short-term photovoltaic output prediction based on the solar irradiance prediction data. Specifically, the load prediction model is established by selecting a commonly used LSTM neural network for short-term load prediction based on the load characteristics, and inputting corresponding time features, environmental features, and historical correlation features. The model outputs the predicted load for the next 1-24 hours. This is existing technology and will not be elaborated upon further. Similarly, short-term photovoltaic output prediction is also performed using existing technology, employing an LSTM neural network, which will also not be elaborated upon further.

[0035] The obtained short-term photovoltaic output is compared with the predicted load. If the short-term photovoltaic output is greater than the predicted load, it indicates that the photovoltaic output is excessive, and a photovoltaic excess analysis signal is generated. Conversely, if the short-term photovoltaic output is less than the predicted load, it indicates that the photovoltaic output is insufficient, and a photovoltaic deficiency analysis signal is generated.

[0036] Step 2: Process the generated photovoltaic excess analysis signal and collect the current light intensity I. current (Unit: W / m) 2 (e.g., obtained through integrated sensors on photovoltaic panels or weather stations) and the predicted intensity of sunlight during the future time period T. future (e.g., T = 2 hours, matching the short-term photovoltaic forecast cycle) and calculate the difference ΔI = I future -I current Set the light intensity judgment threshold I th (Set by maintenance personnel based on the lighting characteristics of the system's location), if ΔI>I th If the predicted future solar irradiance is strong, the charging threshold needs to be increased, generating a signal to increase the charging threshold (to reserve more energy storage capacity for subsequent periods and avoid curtailment due to continued oversupply of photovoltaic power). If ΔI≤I thIf the forecast of weak future sunlight is determined, the charging threshold needs to be lowered, and a signal to reduce the charging threshold is generated (to reduce the reserved space for energy storage, prioritize the consumption of excess photovoltaic, and avoid energy storage redundancy when there is insufficient sunlight in the future).

[0037] By combining photovoltaic forecasts, load forecasts, and energy storage capacity, the upper limit of the charging threshold is derived. The upper limit of the charging threshold SOC is calculated. max , where P PV预测 P represents the short-term photovoltaic output within the future Δt period. Load预测 This represents the predicted load within the future Δt, where η is the charge / discharge efficiency, based on the obtained upper limit of the charging threshold SOC. max Based on the "strong / weak" determination result of the illumination prediction, combined with the upper limit of the threshold SOC max Adjust the real-time charging threshold;

[0038] Calculate the adjustable charging threshold range, ΔSOC = SOC max -SOC 实时 Adjust according to the light prediction enhancement ratio. Similarly, calculate the charging adjustment threshold when the charging threshold decreases.

[0039] For example, the current SOC current =50%, real-time charging threshold SOC 实时 =70%, rated energy storage capacity E 额定 =10kWh, current illumination I current =800W / m 2 Light forecast for the next 2 hours I future =1100W / m 2 (ΔI=300W / m 2 );

[0040] Set the judgment threshold I th =200W / m 2 Since ΔI = 300 > 200, it is determined that "future sunlight will be strong," and the charging threshold needs to be increased. Short-term photovoltaic forecast P... pv预测 =6kW, load forecast P Load预测 =2kW, charging efficiency η=0.9.

[0041] Threshold upper limit calculation Light enhancement ratio Increase the threshold proportionally The calculated threshold of 79.375% was then used as the standard for adjustment, resulting in a final discharge adjustment threshold of 79.375%.

[0042] Step 3: Next, obtain the real-time photovoltaic output and load power, where the load power is expressed as real-time load power. Simultaneously, obtain the real-time state of charge (SOC) and compare it with the charging adjustment threshold. If the real-time SOC is less than the charging adjustment threshold, it indicates that charging control can continue. Then, according to formula P... ch =min(P PV实时 -P Load实时 P bat，max f(SOC)) is used to obtain the corresponding charging power P. ch And the minimum charging power calculated here according to the formula is P. bat，max Let f(SOC) be the maximum allowable charging power of the energy storage battery, and let f(SOC) be the charging power limit function based on SOC. The charging power is adjusted according to f(SOC) to generate charging regulation information. Specifically, if the real-time charging power is greater than the calculated charging power P... ch If the value is less than the specified value, no adjustment is made; otherwise, adjustment is made based on the specified value.

[0043] Based on the actual situation, let's assume P pv实时 =10kW (10 kWh of photovoltaic power generation), P Load实时 =3kW (load at 3 kWh / hour), then the theoretical excess value of photovoltaic power is 10-3=7kW, P bat，max =5kW (the battery allows a maximum charging power of 5kW);

[0044] If SOC = 80%, and f(SOC) = 3kW (high SOC limits charging power), then P ch =min(7,5,3)=3kW, the battery is actually charged at 3kW (because the SOC limit is the strictest, and battery safety is given priority).

[0045] If the real-time state of charge is greater than the charging adjustment threshold, it means that the energy storage system has reached the charging limit and needs to be diverted. If the system is equipped with local load adjustable resources (such as electrical equipment that can be delayed to start, such as electric water heaters, air conditioners, etc.), the excess power is preferentially directed to these loads to achieve local consumption. If it is connected to the grid and has grid connection conditions, the excess power is fed into the grid and the energy is effectively utilized through the electricity sales model.

[0046] If local consumption and grid connection are both not feasible, the power limiting protection mechanism of the photovoltaic system is activated to reduce the output power of the photovoltaic inverter, so that the photovoltaic power generation matches the local real-time load demand and generates charging adjustment information.

[0047] For example, photovoltaic output P pv实时 =15kW, load PLoad实时 =5kW, SOC 实时 =85%, charging adjustment threshold is 80%, battery maximum charging power Pbat,max =6kW, f(85%) =2kW, grid connection limit P grid，max =5kW, adjustable load capacity 3kW, SOC comparison 85%>80%, enters the diversion process, photovoltaic excess power: 15kW-5kW=10kW, start 3kW adjustable load, remaining excess power 10kW-3kW=7kW, grid-connected 5kW, remaining excess power 7kW-5kW=2kW, adjust photovoltaic inverter, reduce output from 15kW to 5kW (load demand)+3kW (adjustable load)+5kW (grid-connected)=13kW, final curtailed power: 15kW-13kW=2kW.

[0048] Step 5: Process the generated photovoltaic deficiency analysis signal, analyze the sunshine prediction data, and generate a signal to increase or decrease the discharge threshold based on future sunshine predictions. The processing method here is the same as that for the photovoltaic excess analysis signal, and is based on the formula... The lower limit of discharge threshold SOC was calculated. max , where P PV预测 P represents the short-term photovoltaic output within the future Δt period. Load预测 This represents the predicted load within the future Δt, where η is the charging and discharging efficiency. Simultaneously, it is adjusted based on the generated signal to increase or decrease the discharge threshold, generating a discharge adjustment threshold. The specific adjustment method here is the same as that of the photovoltaic excess analysis signal.

[0049] Step 6: Next, obtain the real-time photovoltaic output and load power, and obtain the corresponding real-time state of charge. Compare this with the discharge adjustment threshold. If the real-time state of charge is greater than the discharge adjustment threshold, it indicates that discharge control can continue, according to formula P. dis =min(P Load实时 -P PV实时 P bat，max The corresponding discharge power P is obtained from f(SOC). dis The discharge is regulated based on the calculated discharge power, and discharge regulation information is generated simultaneously.

[0050] For example, the current SOC current =60%, real-time charging threshold SOC 实时 =40%, rated energy storage capacity E 额定 =100kWh, current illumination I current =700W / m 2 Light forecast for the next 2 hours I future =500W / m 2 (ΔI=-200W / m 2 );

[0051] Set the judgment threshold I th=150W / m 2 Since ΔI = -200 < 150, it is determined that future sunlight will weaken, and the discharge threshold needs to be reduced. Short-term photovoltaic forecast P pv预测 =5kW, load forecast P Load预测 =12kW, charging efficiency η=0.92,

[0052] Threshold lower limit calculation Light enhancement ratio Reduce the threshold proportionally The calculated threshold of 32.86% was then used as the standard for adjustment, resulting in a final discharge adjustment threshold of 32.86%.

[0053] When the real-time state of charge is less than the discharge adjustment threshold, the active discharge circuit of the energy storage is cut off (e.g., by controlling the discharge power to 0 through the PCS converter) to avoid the energy storage consuming electricity in the "unnecessary discharge range" and ensure the ability to cope with more urgent power supply needs in the future. The energy storage SOC is collected in a 1-minute cycle to capture its changes caused by self-discharge (e.g., the daily average self-discharge rate of lithium batteries is 0.5%-1%) or small loads (e.g., the power consumption of the system control unit). The real-time power of the photovoltaic panel is tracked synchronously (time granularity of 10 seconds) to identify whether the photovoltaic output is continuously lower than the load demand.

[0054] When the real-time state of charge (SOC) is monitored to be less than or equal to the discharge adjustment threshold, the discharge power is calculated based on the load gap and energy storage safety constraints, according to the formula P. dis =min(P Load实时 -P PV实时 P bat，dis，max , g(SOC)), where P bat，dis，max For the maximum allowable discharge power of energy storage, g(SOC) represents the discharge limit function related to SOC, and is expressed as the calculated discharge power P. dis Discharge is performed according to the standard, generating discharge regulation information.

[0055] The data in the above formulas are all calculated using numerical values, without substituting the parameter units. In addition, the contents not described in detail in this specification are all prior art known to those skilled in the art.

[0056] The above embodiments are only used to illustrate the technical methods of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical methods of the present invention without departing from the spirit and scope of the technical methods of the present invention.

Claims

1. A charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds, characterized in that, The method specifically includes the following steps: Based on the load forecasting model and the short-term forecasting model, the predicted load and short-term photovoltaic output are obtained respectively, and the two values ​​are compared to generate a photovoltaic insufficiency or photovoltaic surplus analysis signal. The photovoltaic excess analysis signal is processed to generate signals to increase or decrease the charging threshold based on changes in future predicted solar irradiance. Simultaneously, the upper limit of the charging threshold is calculated according to a formula and adjusted proportionally based on changes in future predicted solar irradiance to obtain the charging adjustment threshold. The specific processing method is as follows: The generated photovoltaic excess analysis signal is processed, and the sunshine prediction data is analyzed. If the future sunshine prediction is strong, a signal to increase the charging threshold is generated; if the future sunshine prediction is weak, a signal to decrease the charging threshold is generated. Obtain the rated energy storage capacity E of the photovoltaic energy storage system 额定 and real-time energy storage SOC 实时 At the same time, according to the formula The upper limit of the charging threshold SOC is calculated. max , where P PV预测 Indicates the future Short-term photovoltaic output within the region, P Load预测 Indicates the future Predicted load within, For charge / discharge efficiency, based on the obtained upper limit of the charging threshold SOC max Calculate the adjustable charging threshold range. Adjust according to the light prediction enhancement ratio. Similarly, the charging adjustment threshold is calculated when the charging threshold is reduced. The system acquires the real-time state of charge and compares it with the charging adjustment threshold. If the latter is large, the charging power is determined according to the formula. If the latter is small, the energy storage system is diverted and charging adjustment information is generated. The system acquires real-time photovoltaic output and load power, along with real-time state of charge (SOC), and compares these with a charging adjustment threshold. If the SOC is less than the threshold, charging control can continue. Then, according to the formula... Obtain the corresponding charging power P ch And P ch The minimum charging power is P. bat，max The maximum allowable charging power of the energy storage battery is given by f(SOC), which is a charging power limitation function based on SOC. The charging power is adjusted according to SOC to generate charging regulation information. The photovoltaic insufficiency analysis signal is processed to generate a signal to increase or decrease the discharge threshold based on the change in the predicted future light intensity. At the same time, the lower limit of the discharge threshold is calculated according to the formula and adjusted proportionally based on the change in the predicted future light intensity to obtain the discharge adjustment threshold. The system acquires the real-time state of charge and compares it with the discharge adjustment threshold. If the latter is large, the system calculates the discharge power based on the load gap and energy storage safety constraints. If the latter is small, the system calculates the discharge power according to the formula and generates discharge adjustment information.

2. The charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds according to claim 1, characterized in that, The specific method for generating the photovoltaic insufficiency or photovoltaic excess analysis signal is as follows: Collect real-time photovoltaic power output, sunshine forecast, real-time load and historical data; build a load forecasting model based on historical data to obtain the predicted load; combine sunshine forecast to make short-term photovoltaic power output forecast. By comparing short-term photovoltaic (PV) output with predicted load, a larger former indicates PV oversupply, generating an oversupply signal; a smaller former indicates PV undersupply, generating an undersupply signal.

3. The charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds according to claim 1, characterized in that, The specific method for diverting energy from the energy storage system is as follows: If the real-time state of charge is greater than the charging adjustment threshold, it means that the energy storage system has reached the charging limit and needs to be diverted. If the system is equipped with local load adjustable resources, the excess power will be directed to the load first. If it is connected to the grid and has grid connection conditions, the excess power will be fed into the grid. If local consumption and grid connection are both not feasible, the power limiting protection mechanism of the photovoltaic system is activated to reduce the output power of the photovoltaic inverter and generate charging regulation information.

4. The charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds according to claim 1, characterized in that, The specific method for processing the photovoltaic insufficiency analysis signal is as follows: Analyze illumination prediction data, generate signals to increase or decrease the discharge threshold based on future illumination predictions, and simultaneously apply the formula... The lower limit of discharge threshold SOC was calculated. max , where P PV预测 Indicates the future Short-term photovoltaic output within the region, P Load预测 Indicates the future Predicted load within, To improve charging and discharging efficiency, the discharge adjustment threshold is generated by adjusting the discharge threshold based on the generated signal that increases or decreases the discharge threshold.

5. The charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds according to claim 1, characterized in that, The specific method for calculating discharge power based on load gap and energy storage safety constraints is as follows: If the real-time state of charge is less than the discharge adjustment threshold, the discharge power is calculated based on the load gap and energy storage safety constraints, according to the formula. , where P bat，dis，max For the maximum allowable discharge power of energy storage, g(SOC) represents the discharge limit function related to SOC, and is expressed as the calculated discharge power P. dis Discharge is performed according to the standard, generating discharge regulation information.

6. The charging and discharging control method for a photovoltaic energy storage system based on dynamic thresholds according to claim 1, characterized in that, The specific method for calculating the discharge power according to the formula is as follows: The system obtains real-time photovoltaic output and load power, acquires the corresponding real-time state of charge (SOC), and compares it with a discharge adjustment threshold. If the real-time SOC is greater than the discharge adjustment threshold, it indicates that discharge control can continue, according to the formula... Obtain the corresponding discharge power P dis The discharge is regulated based on the calculated discharge power, and discharge regulation information is generated simultaneously.

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