Energy storage device operation control system and method in low temperature environment

Abstract

The application discloses a low-temperature environment energy storage device operation control system, which comprises a charging and discharging trigger condition judgment module, a dischargeable electric quantity and residual discharge working time calculation module, a discharge power control parameter acquisition module, a charging and discharging cutoff condition judgment module, an actual chargeable electric quantity and residual charging working time calculation module and a charging power control parameter acquisition module. The application proposes a discharge cutoff condition and charging and discharging power control parameter calculation mode considering a low-temperature operation environment, so as to provide a method for realizing fine operation control following temperature change without increasing additional devices and costs, and improve the adaptability of the energy storage device in a low-temperature operation.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of battery energy storage, and particularly relates to an energy storage device operation control system and method in a low-temperature environment. BACKGROUND

[0002] With the proposal of the "3060" target, the production and consumption of energy develop in a more low-carbon and efficient direction, and new energy power generation will become the main body of a new power system. As an important content of vigorously developing new energy grid-connected power generation, source-grid-load-storage and wind-solar-water-fire storage, new power storage technology represented by lithium batteries has been widely used in various scenarios. However, in a complex application environment, the performance of lithium batteries is different, which affects the execution of the energy storage operation strategy and reduces the energy storage utilization rate and efficiency. Especially in a low-temperature environment, the available capacity and charge-discharge power characteristics of lithium batteries are significantly affected by the ambient temperature, and the available energy and power attenuation are relatively serious. Even the SOC calculated by the battery management system with temperature calibration often causes serious distortion of the results due to the cumulative error of operation, resulting in unreasonable or unexecutable energy storage charge-discharge operation strategy. In particular in the northeast, northwest and east of Inner Mongolia of China, the extremely low temperature in winter poses a great challenge to the outdoor operation of energy storage devices. In order to cope with the operation control problem of energy storage devices in a low-temperature environment, a common method is to add an auxiliary heating system power module to the energy storage device.

[0003] CN108988472A discloses an energy storage power supply applied to a low-temperature environment. The application discloses an energy storage power supply system applied to a low-temperature environment, which comprises a high-energy storage battery, a low-temperature storage battery, a storage battery controller, a temperature sensor, an electric heating film device and a plurality of control switches. The electric heating film device is arranged in the high-energy storage battery. The temperature sensor is arranged near the storage battery in the system cabinet. The storage battery controller is a central control system of the system, is provided with a temperature information and storage battery information acquisition circuit and control switches, and realizes management of the whole energy storage power supply. The method has the advantages that the auxiliary power supply provides heat energy for the main power supply and provides conditions for the stable working environment of the main power supply. However, the auxiliary power supply increases the overall cost of the device, and the auxiliary power supply needs to be replaced frequently, which increases the operation and maintenance cost and risk points.

[0004] CN112883596B discloses a high-efficiency operation method of a battery energy storage system at low temperature, and discloses a high-efficiency operation method of a battery energy storage system at low temperature. The application establishes an energy storage system framework by taking two kinds of battery joint scheduling as an example, selects lithium iron phosphate battery and lithium titanate battery for joint scheduling to make the two batteries complementary; then, a two-battery joint scheduling energy storage system model considering the influence of temperature on the input and output efficiency of the battery is established; finally, the optimal scheduling scheme of the battery energy storage system composed of lithium titanate battery and lithium iron phosphate battery at low temperature is given. The application realizes high-efficiency power output of the battery energy storage system at low temperature, realizes the complementary advantages of different types of batteries, and also ensures low overall cost. However, the application needs two kinds of batteries, and is based on the characteristics of lithium iron phosphate battery and lithium titanate battery, which has great complexity in the assembly from battery to energy storage system device, greatly increasing the operation difficulty. SUMMARY

[0005] The purpose of the present application is to provide a low-temperature environment energy storage device operation control system and method, which considers the sensitivity of voltage to low-temperature environment and the influence of low temperature on charge and discharge power, improves the operation adaptability to low-temperature environment without increasing additional devices and cost, and is beneficial to safe and stable operation.

[0006] To achieve this purpose, the low-temperature environment energy storage device operation control system designed by the present application includes a charge and discharge trigger condition judgment module, a dischargeable electric quantity and residual discharge working time calculation module, a discharge power control parameter acquisition module, a charge and discharge cutoff condition judgment module, an actual chargeable electric quantity and residual charge working time calculation module, and a charge power control parameter acquisition module.

[0007] The charge and discharge trigger condition judgment module is used to judge whether the energy storage device reaches the charge trigger condition or the discharge trigger condition according to the clock time of the energy storage device;

[0008] The dischargeable electric quantity and residual discharge working time calculation module is used to calculate the actual dischargeable electric quantity and the residual discharge working time of the energy storage device respectively according to the dischargeable electric quantity of the energy storage device detected by the BMS, the residual electric quantity at the expected cutoff discharge time, the current clock time and the discharge time interval;

[0009] The discharge power control parameter acquisition module is used to obtain the discharge power control parameter according to the actual dischargeable electric quantity, the residual discharge working time, the dischargeable current detected by the BMS, the battery pack terminal voltage of the energy storage device, and the temperature corresponding to the current lowest temperature battery in the energy storage battery pack, and transmit the discharge power control parameter to the energy storage converter for execution;

[0010] The charge and discharge cutoff condition judgment module is used to judge whether the energy storage device reaches the charge and discharge cutoff condition;

[0011] The actual rechargeable capacity and remaining charging time calculation module is used to calculate the actual rechargeable capacity and remaining charging time of the energy storage device based on the rechargeable capacity, rechargeable current, expected rechargeable capacity at the end of charging, current clock time and charging time interval of the energy storage device detected by the BMS.

[0012] The charging power control parameter acquisition module is used to obtain charging power control parameters based on the actual rechargeable capacity, remaining charging time, rechargeable capacity detected by BMS, battery pack terminal voltage of the energy storage device, and the temperature of the battery with the lowest current temperature in the energy storage battery pack, and then transmits the charging power control parameters to the energy storage converter for execution.

[0013] This invention proposes a calculation method that takes into account the low-temperature operating environment, using the voltage change rate as the discharge cutoff condition and the charging and discharging power control parameters. This provides a method for energy storage devices operating in low-temperature environments to achieve refined operation control by following temperature changes without adding extra devices or costs, thereby improving the adaptability of energy storage devices to low-temperature operation.

[0014] This invention achieves operational control of energy storage devices through optimized control methods, without adding any auxiliary devices, thus reducing overall costs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the present invention;

[0016] Figure 2 This is a flowchart of the present invention.

[0017] Among them, 1—charge and discharge trigger condition judgment module, 2—dischargeable capacity and remaining discharge working time calculation module, 3—discharge power control parameter acquisition module, 4—charge and discharge cutoff condition judgment module, 5—actual rechargeable capacity and remaining charging working time calculation module, and 6—charging power control parameter acquisition module. Detailed Implementation

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments:

[0019] like Figure 1 The energy storage device operation control system shown in the low temperature environment includes a charging and discharging trigger condition judgment module 1, a dischargeable capacity and remaining discharge working time calculation module 2, a discharge power control parameter acquisition module 3, a charging and discharging cutoff condition judgment module 4, an actual chargeable capacity and remaining charging working time calculation module 5, and a charging power control parameter acquisition module 6.

[0020] The energy storage device is placed in an outdoor environment for operation, and the energy storage device comprises a battery pack, a battery management system (BMS), an energy storage converter, an on-site monitoring device, a temperature control device, and the like.

[0021] The charge-discharge trigger condition judgment module 1 is configured to determine whether the energy storage device reaches a charge trigger condition or a discharge trigger condition according to a clock time of the energy storage device.

[0022] The dischargeable electric quantity and residual discharge working time calculation module 2 is configured to calculate the actual dischargeable electric quantity and the residual discharge working time of the energy storage device, respectively, according to the dischargeable electric quantity of the energy storage device detected by the BMS, the residual electric quantity at the expected cutoff discharge time, the current clock time, and the discharge time interval (a set of planned discharge time periods in a day, and the charge is the same).

[0023] The discharge power control parameter acquisition module 3 is configured to obtain the discharge power control parameter according to the actual dischargeable electric quantity, the residual discharge working time, the dischargeable current detected by the BMS, the terminal voltage of the battery pack of the energy storage device, and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack (the lowest value among all battery temperatures detected by the BMS), and transmit the discharge power control parameter to the energy storage converter for execution.

[0024] The charge-discharge cutoff condition judgment module 4 is configured to determine whether the energy storage device reaches a charge-discharge cutoff condition.

[0025] The actual chargeable electric quantity and residual charge working time calculation module 5 is configured to calculate the actual chargeable electric quantity and the residual charge working time of the energy storage device according to the chargeable electric quantity of the energy storage device detected by the BMS, the chargeable current of the energy storage device, the chargeable electric quantity of the energy storage device at the expected cutoff charge time, the current clock time, and the charge time interval.

[0026] The charge power control parameter acquisition module 6 is configured to obtain the charge power control parameter according to the actual chargeable electric quantity, the residual charge working time, the chargeable electric quantity detected by the BMS, the terminal voltage of the battery pack of the energy storage device, and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack (the lowest value among all battery temperatures detected by the BMS), and transmit the charge power control parameter to the energy storage converter for execution.

[0027] In the above technical solution, the charge trigger condition refers to the current clock time t of the energy storage device being in the energy storage planned charge time interval T C , and the discharge trigger condition refers to the current clock time t of the energy storage device being in the discharge time interval T D .

[0028] In the above technical solution, the actual dischargeable electric quantity E dThe energy storage device dischargeable electric quantity E detected by the BMS D And the expected remaining electric quantity E1 at the cutoff discharge, calculated as follows:

[0029] E d = E D -E1;

[0030] The energy storage device actually chargeable electric quantity E detected by the BMS C And the expected chargeable electric quantity E2 at the cutoff charge, calculated as follows:

[0031] E c = E C -E2.

[0032] In the above technical solution, the remaining discharge working duration L TD Is obtained from the current clock time t and the discharge time interval T D ;

[0033] L TD = L Td -L td , L Td represents the duration within the discharge time interval (determined by the discharge time interval T D ), and Ltd represents the current elapsed duration within the discharge time interval (determined by the current clock time t).

[0034] The remaining charge working duration L TC Is obtained from the current time state t and the charge time interval T C .

[0035] L TC = L Tc -L tc , L Tc represents the duration within the charge time interval (determined by the charge time interval T C ), and Ltc represents the current elapsed duration within the charge time interval (determined by the current time state t).

[0036] In the above technical solution, the discharge power control parameter P D Is calculated according to the actual dischargeable electric quantity E d , the remaining discharge working duration L TD , the maximum dischargeable current I D detected by the BMS, the energy storage device battery pack terminal voltage U D , and the temperature T corresponding to the current temperature lowest battery in the energy storage battery pack, calculated as follows:

[0037] P d = U D ·ID

[0038]

[0039] wherein P d represents the maximum dischargeable power.

[0040] In the above technical solution, the discharge cutoff condition is that the energy storage device is not in the discharge time interval or the state of charge of the energy storage device reaches the discharge cutoff state of charge SOC DS or the voltage rate of change θ is greater than or equal to the critical value of the voltage rate of change under the current temperature condition.

[0041] wherein the voltage rate of change θ is calculated as follows:

[0042] θ = (Vmax(t) - Vmin(t)) / Vmax(t);

[0043] wherein Vmax(t) and Vmin(t) are the maximum voltage and minimum voltage values detected by the BMS of the energy storage device at time t.

[0044] In the above technical solution, the method for calculating the critical value of the voltage rate of change θ 0，T under different temperature conditions according to the open-circuit voltage curve of the battery cell under different temperatures is as follows:

[0045] θ 0，T = max(U(SOC i )-U(SOC i-0.1 )) / 0.1(i∈(0.1, 0.2, …, 1))

[0046] wherein θ 0，T represents the critical voltage rate of change under the temperature T; and U(SOC i ) represents the terminal voltage when the state of charge of the battery is i.

[0047] In the above technical solution, the charging power control parameter P c is calculated according to the actual chargeable electric quantity E c , the remaining charging work length L TC , the maximum chargeable current I C detected by the BMS, the terminal voltage U D of the energy storage device battery pack, and the temperature T1 corresponding to the battery with the lowest temperature in the energy storage battery pack, and the specific calculation method is as follows:

[0048] P c = U D · I C

[0049]

[0050] P c This represents the maximum rechargeable power.

[0051] In the above technical solution, the charging cutoff condition is that the energy storage device's state of charge reaches the energy storage device's charging protection voltage or the energy storage device's charging cutoff state of charge (SOC). CS .

[0052] A method for operating and controlling an energy storage device in a low-temperature environment, such as Figure 2 As shown, this method, based on conventional energy storage devices operating outdoors, uses the open-circuit voltage curves of battery cells at different temperatures, and the battery temperature, battery voltage, chargeable / dischargeable current, chargeable / dischargeable capacity, and battery state of charge detected by the battery management system (BMS) to obtain the critical value of voltage change rate, charge / discharge trigger conditions, charge / discharge cutoff conditions, and charge / discharge power control parameters under different low-temperature conditions. Through adaptive operation logic judgment and calculation, the final command is sent to the energy storage converter for execution, thus completing the adaptive operation of the energy storage device.

[0053] It includes the following steps:

[0054] Step 1: Determine whether the energy storage device has reached the discharge trigger condition based on the energy storage device's clock time;

[0055] Step 2: If the clock time of the energy storage device reaches the discharge trigger condition, calculate the actual dischargeable capacity and remaining discharge working time of the energy storage device based on the dischargeable capacity of the energy storage device detected by the BMS, the remaining capacity at the expected discharge cutoff time, the current clock time, and the discharge time interval.

[0056] Step 3: Based on the actual dischargeable capacity, remaining discharge working time, dischargeable current detected by BMS, battery pack terminal voltage of the energy storage device, and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack, obtain the discharge power control parameters, and transmit the discharge power control parameters to the energy storage converter for execution.

[0057] Step 4: Determine whether the energy storage device has reached the discharge cutoff condition;

[0058] Step 5: If the discharge cutoff condition is met, further determine whether the energy storage device has met the charging trigger condition. If the discharge cutoff condition is not met, recalculate the discharge power and continue discharging.

[0059] If the energy storage device reaches the discharge cutoff condition but does not reach the charging trigger condition, it will be left to stand still. Standing still means that the clock time t is neither in the discharge time interval nor in the charging time interval.

[0060] Step 6: If the energy storage device reaches the charging trigger condition, the actual chargeable capacity and the remaining charging working time of the energy storage device are calculated according to the chargeable capacity and the chargeable current of the energy storage device detected by the BMS, the expected chargeable capacity of the energy storage device at the expected cut-off charging time, the current clock time and the charging time interval;

[0061] Step 7: The charging power control parameter is obtained according to the actual chargeable capacity, the remaining charging working time, the chargeable current, the terminal voltage of the battery pack of the energy storage device and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack detected by the BMS, and the charging power control parameter is transmitted to the energy storage converter for execution;

[0062] Step 8: It is judged whether the energy storage device reaches the charging cut-off condition;

[0063] Step 9: If the charging cut-off condition is reached, it is further judged whether the energy storage device reaches the discharging trigger condition, and if the charging cut-off condition is not reached, the charging power is recalculated and the charging is continued;

[0064] If the energy storage device reaches the charging cut-off condition but does not reach the discharging trigger condition, it is static and returns to step 1.

[0065] The key of the control logic is that on the one hand the amount of remaining capacity is taken into account for control, and the mismatch between the displayed remaining capacity and the actual remaining capacity is grasped, and the actual chargeable / dischargable capacity is corrected; on the other hand, the control grasps the influence of the temperature change of the battery on the terminal voltage of the battery, that is, the sensitivity of the battery voltage change is taken as the condition for controlling the running state of the battery, and a power output calculation formula is provided based on this, which further enhances the running ability of the battery in a low temperature environment.

[0066] Example 1:

[0067] If the capacity of the energy storage device is 50kW / 100kWh, the ambient temperature T h is 5℃, the discharging cut-off SOC DS is 15%, the remaining dischargable capacity E1=7.5kWh corresponding to the expected cut-off discharging time, the charging cut-off SOC CS is 95%, the chargeable capacity E2=2.5kWh corresponding to the expected cut-off charging time; the discharging time interval T D is 17:30-23:00, the planned charging time interval T C is 0:00-7:00, and the remaining time is the static time. The open circuit voltage curve of the battery cell under the temperature 5℃ condition is calculated to obtain the voltage critical change rate θ 0，T is 0.1 (provided by the battery vendor).

[0068] The dischargable current I D and the terminal voltage U D, battery minimum temperature T, chargeable electric quantity E C chargeable current I C , terminal voltage U C , battery minimum temperature T, battery maximum voltage Vmax(t), minimum voltage value Vmin(t) are all detection values of BMS at time t.

[0069] From the above parameter values and formula, the voltage change rate θ, the actual dischargeable electric quantity E d , discharge power control parameter P D , actual chargeable electric quantity E c , charge power control parameter P c .

[0070] According to the above embodiment parameter setting, the running state adjustment and the adjustment of the power control parameter can be dynamically and real-timely performed according to the environmental temperature and the battery temperature change condition.

[0071] The contents not described in detail in the specification belong to the prior art known to the person skilled in the art.

Claims

1. A control system for an energy storage device operating in a low-temperature environment, characterized in that: It includes charge and discharge trigger condition judgment module (1), dischargeable electric quantity and remaining discharge working time calculation module (2), discharge power control parameter acquisition module (3), charge and discharge cutoff condition judgment module (4), actual chargeable electric quantity and remaining charge working time calculation module (5), charge power control parameter acquisition module (6); The charge and discharge trigger condition judgment module (1) is used for judging whether the energy storage device reaches the charge trigger condition or the discharge trigger condition according to the clock time of the energy storage device; The dischargeable electric quantity and remaining discharge working time calculation module (2) is used for calculating the actual dischargeable electric quantity and the remaining discharge working time of the energy storage device respectively according to the dischargeable electric quantity of the energy storage device detected by the BMS, the remaining electric quantity at the expected cutoff discharge time, the current clock time and the discharge time interval; The discharge power control parameter acquisition module (3) is used for obtaining the discharge power control parameter according to the actual dischargeable electric quantity, the remaining discharge working time, the dischargeable current detected by the BMS, the battery pack terminal voltage of the energy storage device and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack, and transmitting the discharge power control parameter to the energy storage converter for execution; The charge and discharge cutoff condition judgment module (4) is used for judging whether the energy storage device reaches the charge and discharge cutoff condition; The actual chargeable electric quantity and remaining charge working time calculation module (5) is used for calculating the actual chargeable electric quantity and the remaining charge working time of the energy storage device according to the chargeable electric quantity of the energy storage device detected by the BMS, the chargeable current of the energy storage device, the chargeable electric quantity at the expected cutoff charge time of the energy storage device, the current clock time and the charge time interval; The charge power control parameter acquisition module (6) is used for obtaining the charge power control parameter according to the actual chargeable electric quantity, the remaining charge working time, the chargeable electric quantity detected by the BMS, the battery pack terminal voltage of the energy storage device and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack, and transmitting the charge power control parameter to the energy storage converter for execution; Discharge power control parameter P D According to the actual dischargeable electric quantity E d , the remaining discharge working time L TD , the dischargeable current I detected by the BMS D , the terminal voltage U of the energy storage device battery pack D The temperature T corresponding to the current temperature lowest battery in the energy storage battery pack is calculated, and the calculation formula is as follows: P d = U D · I D where P d represents the maximum dischargeable power; Charging power control parameter P c According to the actual chargeable electric quantity E c , the remaining charging work length L TC , the maximum chargeable current I detected by the BMS C , the terminal voltage U of the energy storage device battery pack D , the temperature T1 corresponding to the battery with the lowest current temperature in the energy storage battery pack is calculated, and the specific calculation method is as follows: P c =U D ·U C P c is the maximum chargeable power.

2. The cryogenic energy storage device operation control system of claim 1, wherein: The charging trigger condition refers to the current clock time t of the energy storage device being in the energy storage planned charging time interval T C The discharging trigger condition refers to the current clock time t of the energy storage device being in the discharging time interval T D .

3. The cryogenic energy storage device operation control system of claim 1, wherein: The actual dischargeable electric quantity E of the energy storage device d The actual dischargeable electric quantity E of the energy storage device detected by the BMS D And the residual electric quantity E1 at the expected cut-off discharge is calculated, and the calculation formula is as follows: E d = E D - E1; The actual chargeable electric quantity of the energy storage device is calculated according to the chargeable electric quantity E of the energy storage device detected by the BMS C And the expected chargeable electric quantity E2 at the cut-off charging time is calculated, and the calculation formula is as follows: E c = E C - E2.

4. The cryogenic energy storage device operation control system of claim 1, wherein: The remaining discharge working time length L TD from the current clock time t and the discharge time interval T D is obtained; L TD = L Td - L td , L Td represents the time length within the discharge time interval, and Ltd represents the time length within the discharge time interval that has elapsed at present. Remaining charging working time length L TC from the current time state t and the discharge time interval T C obtained; L TC = L Tc - L tc , L Tc represents the time length within the charging time interval, and Ltc represents the current elapsed time length within the charging time interval.

5. The cryogenic energy storage device operation control system of claim 1, wherein: The discharge cut-off condition is that the energy storage device is not in the discharge time interval or the state of charge of the energy storage device reaches the discharge cut-off state of charge SOC DS or the voltage change rate θ is greater than or equal to the critical value of the voltage change rate under the current temperature condition; Wherein, the voltage change rate θ is calculated as follows: θ=(Vmax(t)-Vmin(t)) / Vmax(t); Wherein, Vmax(t), Vmin(t) are respectively the maximum voltage and the minimum voltage value of the battery detected by the BMS of the energy storage device at t moment.

6. The cryogenic energy storage device operation control system of claim 5, wherein: The critical value of voltage variation rate θ under different temperature conditions is calculated according to the open circuit voltage curve of the battery cell under different temperatures 0，T The method is as follows: θ 0，T = max(U(SOC i )- U(SOC i-0.1 )) / 0.1 (i e (0.1, 0.2,..., 1)) where θ 0，T represents the critical rate of voltage change under temperature T; U(SOC i ) represents the size of the terminal voltage when the battery state of charge is i.

7. The cryogenic energy storage device operation control system of claim 1, wherein: The charge cut-off condition is that the state of charge of the energy storage device reaches an energy storage device charge protection voltage or an energy storage device charge cut-off state of charge SOC CS .

8. A method for operating a power storage device in a low-temperature environment, comprising: It includes the following steps: ​ Step 1: judging whether the energy storage device reaches the discharge trigger condition according to the clock time of the energy storage device; Step 2: if the clock time of the energy storage device reaches the discharge trigger condition, calculating the actual dischargeable electric quantity and the remaining discharge working time of the energy storage device respectively according to the dischargeable electric quantity of the energy storage device detected by the BMS, the remaining electric quantity at the expected cutoff discharge time, the current clock time and the discharge time interval; Step 3: obtaining the discharge power control parameter according to the actual dischargeable electric quantity, the remaining discharge working time, the dischargeable current detected by the BMS, the battery pack terminal voltage of the energy storage device and the temperature corresponding to the battery with the lowest current temperature in the energy storage battery pack, and transmitting the discharge power control parameter to the energy storage converter for execution; Step 4: judging whether the energy storage device reaches the discharge cutoff condition; Step 4: judging whether the energy storage device reaches the discharge cutoff condition; Step 5: If the discharge cutoff condition is reached, further determine whether the energy storage device reaches the charging trigger condition, if the discharge cutoff condition is not reached, recalculate the discharge power, continue discharging; If the energy storage device reaches the discharge cutoff condition, but does not reach the charging trigger condition, it is static, the clock time t does not belong to the discharge time interval and the charging time interval; Step 6: If the energy storage device reaches the charging trigger condition, according to the BMS detection of the chargeable capacity of the energy storage device, the chargeable current of the energy storage device, the expected cutoff charging capacity of the energy storage device, the current clock time and the charging time interval, the actual chargeable capacity of the energy storage device and the remaining charging working time are calculated; Step 7: According to the actual chargeable capacity, the remaining charging working time, the chargeable capacity detected by the BMS, the battery pack terminal voltage of the energy storage device and the temperature corresponding to the current temperature of the lowest battery in the energy storage battery pack, the charging power control parameter is obtained, and the charging power control parameter is transmitted to the energy storage converter for execution; Step 8: Determine whether the energy storage device reaches the charging cutoff condition; Step 9: If the charging cutoff condition is reached, further determine whether the energy storage device reaches the discharge trigger condition, if the charging cutoff condition is not reached, recalculate the charging power, continue charging; If the energy storage device reaches the charging cutoff condition, but does not reach the discharge trigger condition, it is static, and returns to step 1. Discharge power control parameter P D According to the actual dischargeable electric quantity E d , the remaining discharge working time L TD , the dischargeable current I detected by the BMS D , the terminal voltage U of the energy storage device battery pack D The temperature T corresponding to the battery with the lowest temperature in the energy storage battery pack is calculated, and the calculation formula is as follows: P d = U D · I D where P d represents the maximum dischargeable power; Charging power control parameter P c According to the actual chargeable electric quantity E c , the remaining charging work length L TC , the maximum chargeable current I detected by the BMS C , the terminal voltage U of the energy storage device battery pack D The temperature T1 corresponding to the battery with the lowest current temperature in the energy storage battery pack is calculated as follows: P c = U D • U C P c is the maximum chargeable power.

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