An energy control strategy for bidirectional demand response of energy storage electric vehicle charging stations

Abstract

This invention relates to the field of electric vehicle charging station technology, specifically to an energy control strategy for bidirectional demand response in energy storage-based electric vehicle charging stations. The strategy includes the judgment conditions and execution commands required for the control process. The judgment conditions include: whether a vehicle is charging; peak / valley / normal times; existence of emergency demand from the external power grid; battery charge status; and a comparison between the vehicle's charging power demand, the battery's maximum discharge power, and the maximum power input from the power grid to the charging station. The control strategy primarily selects energy storage charging / discharging control and grid-side power supply control during peak / valley / normal times based on the grid-user bidirectional demand response. This includes grid-connected master-slave control and off-grid islanding control switching according to load size at different times, maximizing user charging needs while minimizing charging costs.

Description

Technical Field

[0001] This invention relates to the field of electric vehicle charging station technology, and in particular to an energy control strategy for bidirectional demand response in energy storage electric vehicle charging stations. Background Technology

[0002] Driven by policies promoting energy conservation, emission reduction, low carbon emissions, and environmental protection, the electric vehicle industry has developed rapidly. However, the construction of supporting charging infrastructure for electric vehicles has not yet met the demand for electric vehicle use. In particular, in older urban areas, the existing power distribution network has not taken into account the load demand of charging stations, and the site selection and construction scale of charging stations are limited by power capacity.

[0003] With the continuous improvement of battery fast-charging performance, the impact and shock of large-scale, continuous fast-charging on the power grid is showing a trend of increasing intensity. In order to meet the pulse charging power requirements of fast-charging stations, applying energy storage systems to fast-charging stations is of great significance for the safe operation of the power grid.

[0004] Patent CN104682536B is "a control method for an energy storage charging station". It replenishes power through energy storage and provides peak energy replenishment. It can use the current power resources for transformer substation power distribution and meet the charging needs of multiple vehicles during peak periods.

[0005] Patent CN112224082B, entitled "A Charging Control Method for an Energy Storage Charging Station," includes the following steps: receiving a charging request from a vehicle; calculating the current total power demand of the energy storage charging station; determining whether the total power demand exceeds the load capacity of the current power distribution network; if not, controlling the energy storage charging station to enter a pure grid power supply mode, whereby the power distribution network supplies power to the charging terminals and energy storage system within the energy storage charging station; if yes, determining whether the load capacity of the current power distribution network exceeds a minimum load threshold; if the load capacity of the current power distribution network exceeds the minimum load threshold, determining whether the energy level of the energy storage system within the energy storage charging station exceeds a first energy level; if the energy level of the energy storage system exceeds the first energy level, controlling the energy storage charging station to enter a partially dependent power supply mode, whereby the energy storage system and the power distribution network jointly supply power to the charging terminals within the energy storage charging station.

[0006] The above technical solutions and existing technologies have the following problems: (1) The control of energy storage configuration for electric vehicle charging stations is basically peak shaving and valley filling, which only reduces the impact of charging stations on the power grid, without considering the economic efficiency of operating costs from the perspective of time-of-use pricing.

[0007] (2) Some charging stations use energy storage charging and discharging control technology based on the comparison between the existing battery power and the charging demand as the conditions for charging and discharging control. However, it is difficult to accurately calculate and obtain the user's demand for electricity through transient data. In particular, the power status, capacity and charging curve of electric vehicles are different, so the control execution is not completely synchronized with the actual demand.

[0008] (3) Current technology only uses energy storage systems as backup capacity for charging stations or as a second power source, without using energy storage power stations as backup capacity for the grid side. When there is an emergency demand on the grid side, energy storage power stations do not play their role, so improvements are needed. Summary of the Invention

[0009] The purpose of this invention is to address the shortcomings of existing technologies by proposing an energy control strategy for bidirectional demand response in energy storage electric vehicle charging stations.

[0010] To achieve the above objectives, the present invention adopts the following technical solution:

[0011] An energy control strategy for bidirectional demand response in an energy storage electric vehicle charging station includes the judgment conditions required for the control process and the commands to be executed by the control process.

[0012] The control process requires the following judgment conditions: whether there is a vehicle charging; peak, valley and normal periods; whether there is an emergency demand from the external power grid; the battery's charge status; and a comparison between the vehicle's charging power demand, the battery's maximum discharge power, and the maximum power input from the power grid to the charging station.

[0013] The commands required to be executed in the control flow include the following steps:

[0014] S1, Battery charging: The grid side charges the battery with maximum input power.

[0015] S2, Battery charging: The grid side supplies power to the charging station with the maximum input power. After the electric vehicle is charged, the remaining power is used to charge the battery.

[0016] S3. The battery is neither charged nor discharged. The grid side charges the electric vehicle at the maximum input power and provides electricity price discounts to users who charge at lower power.

[0017] S4. Battery discharge, the discharge power is equal to the car charging power;

[0018] S5. Battery discharge, the discharge power is equal to the power required to be supplied by the grid on the grid side.

[0019] S6. Battery discharge, the discharge power is equal to the maximum input power on the grid side;

[0020] S7. The battery discharges and charges the car simultaneously with the power grid. The discharge power is equal to the car's charging power minus the maximum input power on the power grid side.

[0021] S8. Battery discharge: The discharge power is equal to the sum of the vehicle charging power and the power required to be supplied by the grid.

[0022] S9. Battery discharge: The discharge power is equal to the sum of the vehicle charging power and the maximum input power on the grid side.

[0023] S10. Battery discharges at its maximum power.

[0024] S11. The battery should not be charged or discharged, and should remain in the previous inspection state.

[0025] S12. If the battery is not being charged or discharged, the power station will suspend operations and notify charging users.

[0026] S13. The battery neither charges nor discharges, and the grid side meets the vehicle charging needs.

[0027] Compared with existing technologies, the control strategy of this application mainly selects energy storage charging and discharging control and grid-side power supply control during peak, valley and normal periods based on the two-way demand response of the grid and users. This includes grid-connected master-slave control and off-grid islanding control, which switch according to the load size at different times. This ensures the charging needs of users are met as much as possible while making the charging cost most economical.

[0028] Preferably, the battery's state of charge is: maximum charge state (SOC). max Maximum depth of discharge capacity (SOC) min Discharge warning capacity SOC 预警 .

[0029] Furthermore, the status of the battery is clearly defined, making it easier for staff to quickly understand the battery's working condition.

[0030] Preferably, the electricity price during the peak-valley and normal periods is as follows: the peak electricity price period is T. 峰 The on-price electricity period is T 平 The off-peak electricity price period is T 谷 .

[0031] Furthermore, to facilitate staff in quickly analyzing charging electricity prices.

[0032] Preferably, the charging load ∑P of the charging station i The charging station is equipped with multiple individual charging piles, and the charging load P of each individual charging pile is... i .

[0033] Furthermore, it allows for a full understanding of the charging load.

[0034] Preferably, the maximum discharge power of the battery is P. batmax .

[0035] Furthermore, this allows staff to better understand the battery's operating status and enables the control process to react quickly based on the battery's operating status.

[0036] Preferably, the grid-side input power is P. in .

[0037] Furthermore, this facilitates the rapid response of the control process based on the operating status of the power grid, providing data support for fully controlling the operation of energy storage electric vehicle charging stations.

[0038] Preferably, the maximum input power on the grid side is P. inmax .

[0039] Furthermore, this facilitates the rapid response of the control process based on the operating status of the power grid, providing data support for fully controlling the operation of energy storage electric vehicle charging stations.

[0040] Preferably, the single charging pile is an electric vehicle charging terminal, including charging terminals with built-in charging modules and charging terminals without charging modules.

[0041] Furthermore, it facilitates connection with the device to be charged, enabling rapid charging operations.

[0042] The beneficial effects of this invention are:

[0043] 1. Utilize off-peak electricity or off-peak pricing periods to store electricity to meet vehicle charging needs, thereby minimizing the electricity cost of charging stations;

[0044] 2. Power indicators are used as monitoring and control conditions, enabling bidirectional energy flow between the power grid, users, and energy storage, resulting in faster and more flexible demand response;

[0045] 3. During peak hours, energy storage will be used as the main power source, while during off-peak hours, the power grid will be used as the main power source, effectively reducing the power supply capacity on the grid side and providing more target options for the location of charging stations;

[0046] 4. In emergency situations, use strategies to make charging stations an emergency power source for the power grid, providing backup capacity to the grid and increasing the social value of the charging stations or the value to the electricity-consuming enterprises above them. Attached Figure Description

[0047] Figure 1 This is a flowchart illustrating the control process steps of an energy control strategy for bidirectional demand response in an energy storage electric vehicle charging station proposed in this invention.

[0048] Figure 2This is a typical topology diagram of an energy storage charging station, which is based on the energy control strategy for bidirectional demand response of an energy storage electric vehicle charging station proposed in this invention.

[0049] Figure 3 This is a second topology diagram of an energy storage charging station for a bidirectional demand response energy control strategy proposed in this invention.

[0050] Figure 4 This is a third topology diagram of an energy storage charging station, which is based on an energy control strategy for bidirectional demand response in an energy storage electric vehicle charging station proposed in this invention. Implementation

[0051] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0052] Reference Figure 1-4 An energy control strategy for bidirectional demand response in energy storage electric vehicle charging stations includes the judgment conditions required for the control process and the commands to be executed by the control process.

[0053] The control process requires the following judgment conditions: whether a vehicle is charging; peak-valley and normal-hour periods, and the electricity price during peak-valley and normal-hour periods: the peak electricity price period is T. 峰 The on-price electricity period is T 平 The off-peak electricity price period is T 谷 Is there an emergency demand from the external power grid? Battery charge status: State of Charge (SOC) max Maximum depth of discharge capacity (SOC) min Discharge warning capacity SOC 预警 The maximum discharge power of the battery is P. batmax A comparison of the power demand for vehicle charging, the maximum discharge power of the battery, and the maximum input power from the power grid to the charging station; and the charging load ∑P of the charging station. i The charging station has multiple individual charging piles, which are electric vehicle charging terminals, including charging terminals with built-in charging modules and charging terminals without charging modules. The charging load P of an individual charging pile is... i The grid-side input power is P in The maximum input power on the grid side is P inmax The constraint condition is: P i <P inmax <P batmax ,∑P i ≤P batmax .

[0054] By setting such Figure 2The diagram shows a typical topology of an energy storage charging station, so that staff can develop control logic flowcharts based on the control units in the topology diagram.

[0055] Furthermore, this application is not limited to energy storage charging stations with different topologies, but can also be applied to, for example... Figure 3 The energy storage bidirectional inverter shown is integrated with the grid-connected inverter into a single structure; it can also be applied to, for example... Figure 4 The charging piles shown are all integrated charging piles, each with its own charging module. The "DC bus" has been changed to "AC bus," the energy storage bidirectional inverter (DC / DC) has been changed to DC / AC, and the grid-connected bidirectional inverter has been changed to a grid-connected static switch.

[0056] The commands required for the control flow to execute include the following steps:

[0057] S1, Battery charging: The grid side charges the battery with maximum input power.

[0058] Battery charging, with the grid side using maximum input power P inmax Charging the battery, i.e., P=P inmax .

[0059] When there is no vehicle charging and no urgent demand from the external power grid, the battery's state-of-the-art (SOC) capacity is... t Less than the maximum state of charge (SOC) max The time is during the off-peak electricity price period T∈[T 谷 In the case of ];

[0060] When there is no vehicle charging and no urgent demand from the external power grid, the battery's state-of-the-art (SOC) capacity is... t Less than the warning state capacity SOC 预警 The time period during the on-peak electricity price and off-peak electricity price period T∈[T 平 T 谷 In the case of ]

[0061] S2. Battery charging: The grid provides power to the charging station at its maximum input power. After the electric vehicle is fully charged, the remaining power is used to charge the battery; charging power P = P inmax -P i ;

[0062] When there is vehicle charging available and no urgent need for external power grid connection, the maximum depth of discharge capacity (SOC) is... min ≤ Battery State Capacity (SOC) t ≤ Warning status capacity SOC 预警 Electric vehicle charging power P i Not greater than the maximum input power P on the grid side inmax The time period during the flat and off-peak electricity price periods T∈[T 平 T 谷In the case of ];

[0063] When there is vehicle charging and no urgent external power grid demand, the warning state capacity (SOC) is... 预警 Battery State-of-Capacity (SOC) t Maximum State of Charge (SOC) max Electric vehicle charging power P i Not greater than the maximum input power P on the grid side inmax The time is during the off-peak electricity price period T∈[T 谷 In the case of ]

[0064] S3. The battery is neither charged nor discharged. The grid side charges the electric vehicle at the maximum input power and provides electricity price discounts to users who charge at lower power.

[0065] When there is a vehicle charging available and no urgent need for external power grid connection, the battery's state-of-the-art (SOC) capacity is... t Equal to the maximum depth of discharge capacity (SOC) min Electric vehicle charging power P i Greater than the maximum input power P on the grid side inmax In this case, the battery neither charges nor discharges, and the grid side charges the electric vehicle P at its maximum input power. i =P inmax The power grid meets the charging supply requirements of the previous inspection cycle. i -1, the remaining power is evenly distributed to subsequent charging users, while a discounted charging price K is given to subsequent users charging with lower power.

[0066] S4. The battery discharges, and the discharge power is equal to the car's charging power; that is, P=P i ;

[0067] When there is a vehicle charging available and no urgent need for external power grid connection, the battery's state-of-the-art (SOC) capacity is... t Exceeding the warning state capacity SOC 预警 The time during peak and off-peak electricity price periods T∈[T 平 T 峰 In the case of ];

[0068] When there is a vehicle charging available and no urgent need for external power grid connection, the battery's state-of-the-art (SOC) capacity is... t ≤ Warning status capacity SOC 预警 The time is during the peak electricity price period T∈[T 峰 In the case of ]

[0069] S5. The battery discharges, and the discharge power is equal to the power required to be supplied by the grid; that is, P=P0 网需 ;

[0070] When there is no vehicle charging available and there is an urgent need for external power grid charging, the battery's state-of-the-art (SOC) capacity is...t greater than the maximum depth of discharge capacity (SOC) min Network load P 网需 ≤P inmax In this case.

[0071] S6. The battery discharges, and the discharge power equals the maximum input power to the grid; that is, P=P0. inmax ;

[0072] When there is no vehicle charging available and there is an urgent need for external power grid charging, the battery's state-of-the-art (SOC) capacity is... t greater than the maximum depth of discharge capacity (SOC) min Network load P 网需 >P inmax In this case.

[0073] S7. The battery discharges while simultaneously charging the vehicle via the power grid. The discharge power equals the vehicle's charging power minus the maximum input power to the power grid; that is, P=P i -P inmax

[0074] When there is vehicle charging available and no urgent need for external power grid, the maximum depth of discharge capacity (SOC) is... min < Battery State of Charge (SOC) t ≤ Warning status capacity SOC 预警 The time period during the flat and off-peak electricity price periods T∈[T 平 T 谷 ], vehicle charging load P i >P inmax In the case of;

[0075] When there is vehicle charging available and no urgent need for external power grid, the battery's state-of-the-art (SOC) capacity is... t >Early warning status capacity SOC 预警 The time is during the off-peak electricity price period T∈[T 谷 ], vehicle charging load P i >P inmax In this case.

[0076] S8. When the battery discharges, the discharge power equals the sum of the vehicle's charging power and the power required to be supplied by the grid; that is, P=P 网需 +P i ;

[0077] When there is vehicle charging available and an emergency demand from the external power grid, the battery's state-of-the-art (SOC) capacity is [not specified]. t Maximum depth of discharge capacity (SOC) min The power grid needs to supply power P. 网需 ≤P inmax The power grid needs to supply power P. 网需 With car charging power Pi The sum of these values ​​should not exceed the battery's maximum discharge power P. batmax In this case.

[0078] S9. When the battery discharges, the discharge power equals the sum of the vehicle's charging power and the maximum input power to the power grid; that is, P=P batmax +P i ;

[0079] When there is vehicle charging available and an emergency demand from the external power grid, the battery's state-of-the-art (SOC) capacity is [not specified]. t Maximum depth of discharge capacity (SOC) min The power grid needs to supply power P. 网需 >P inmax The power grid needs to supply power P. inmax With car charging power P i The sum of these values ​​should not exceed the battery's maximum discharge power P. batmax In this case.

[0080] S10. Battery discharges at its maximum power.

[0081] Discharge power P=P batmax While ensuring the charging of electric vehicles, the external power supply is maximized, with an external power supply capacity of P. batmax -P i ;

[0082] When there is vehicle charging available and an emergency demand from the external power grid, the battery's state-of-the-art (SOC) capacity is [not specified]. t Maximum depth of discharge capacity (SOC) min The power grid needs to supply power P. 网需 >P inmax The power grid needs to supply power P. inmax With car charging power P i The sum of these values ​​is greater than the battery's maximum discharge power P. batmax In the case of;

[0083] When there is vehicle charging available and an emergency demand from the external power grid, the battery's state-of-the-art (SOC) capacity is [not specified]. t Maximum depth of discharge capacity (SOC) min The power grid needs to supply power P. 网需 ≤P inmax The power grid needs to supply power P, and the power grid needs to match the electric vehicle charging power P. i The sum of these values ​​is greater than the battery's maximum discharge power P. batmax In this case.

[0084] S11. The battery should not be charged or discharged, and should remain in the previous inspection state.

[0085] When there is no vehicle charging and no urgent demand from the external power grid, the battery's state-of-the-art (SOC) capacity is... t ≤ Warning status capacity SOC 预警 The time is during the peak electricity price period T∈[T 峰 In the case of ];

[0086] When there is no vehicle charging available and there is an urgent need for external power grid charging, the battery's state-of-the-art (SOC) capacity is... t ≤ Warning status capacity SOC 预警 In this case, the battery neither charges nor discharges, maintaining the previous inspection status and not responding to grid-side demands.

[0087] S12. If the battery is not being charged or discharged, the power station will suspend operations and notify charging users.

[0088] When there is vehicle charging available and an emergency demand from the external power grid, the battery's state-of-the-art (SOC) capacity is [not specified]. t Equal to the maximum depth of discharge capacity (SOC) min If the battery is not being charged or discharged, the power station will suspend operations and notify charging users.

[0089] S13. The battery neither charges nor discharges, and the grid side meets the vehicle charging needs.

[0090] The battery neither charges nor discharges, and the power grid meets the vehicle's charging needs, i.e., P in =P i ;

[0091] When there is a vehicle charging available and no urgent need for external power grid connection, the battery's state-of-the-art (SOC) capacity is... t Equal to the maximum depth of discharge capacity (SOC) min Car charging power P i Not greater than the maximum input power P on the grid side inmax The time is during the peak electricity price period T∈[T 峰 In the case of ];

[0092] When there is a vehicle charging available and no urgent need for external power grid connection, the battery's state-of-the-art (SOC) capacity is... t Equal to the maximum state of charge (SOC) max Car charging power P i Not greater than the maximum input power P on the grid side inmax The time is during the off-peak electricity price period T∈[T 峰 In the case of ]

[0093] The control strategy described above is not limited to the order of the judgment conditions, nor is it limited to the evolution and adjustment of the execution commands. As long as it conforms to the logical thinking of this application, it can achieve the purpose of this application.

[0094] In this invention, in actual use, the order of the various judgment conditions is not limited, nor is the evolution and adjustment of the various execution commands. As long as they conform to the logical ideas of this application, the corresponding components can be made to operate and complete the purpose of this application.

[0095] In other words, when there is no vehicle charging and no emergency demand from the external power grid, the battery is charged by the grid side at the maximum input power Pinmax.

[0096] When there is a vehicle charging and no urgent need for external power grid, the battery is charged. The grid side supplies power to the charging station at the maximum input power. After the electric vehicle is charged, the remaining power is used to charge the battery.

[0097] When there is a vehicle charging and no urgent need for external power grid, the battery will not charge or discharge, and the power grid will charge the electric vehicle at the maximum input power, providing electricity price discounts to users charging at lower power levels.

[0098] When there is a vehicle charging and no urgent need for external power grid, the battery discharges, and the discharge power is equal to the vehicle charging power.

[0099] When there is no vehicle charging and there is an urgent need for power from the external power grid, the battery discharges, and the discharge power is equal to the power that the grid side needs to supply.

[0100] When there is a vehicle charging and no urgent need for external power grid, the battery discharges, and the discharge power is equal to the maximum input power on the grid side.

[0101] When there is a vehicle charging and no urgent need for external power grid, the battery discharges and charges the vehicle simultaneously with the power grid. The discharge power is equal to the vehicle charging power minus the maximum input power on the power grid side.

[0102] When there is a vehicle charging and an emergency demand from the external power grid, the battery discharges, and the discharge power is equal to the sum of the vehicle charging power and the power required to be supplied by the power grid.

[0103] When there is a vehicle charging and an emergency demand from the external power grid, the battery discharges, and the discharge power is equal to the sum of the vehicle charging power and the maximum input power on the power grid side.

[0104] When there is a vehicle charging and an emergency demand from the external power grid, the battery discharges at its maximum power, with a discharge power of P=Pbatmax, so as to meet the power supply needs of the external power grid to the maximum extent while satisfying the vehicle charging needs.

[0105] When there is no vehicle charging and no urgent need for external power grid, or when there is no vehicle charging and an urgent need for external power grid, the battery will neither charge nor discharge, and will remain in the previous inspection state.

[0106] When there is a vehicle charging and an emergency demand from the external power grid, the battery will not charge or discharge, the station will suspend operation, and the charging user will be notified.

[0107] When a vehicle is charging and there is no urgent need for external power grid, the battery neither charges nor discharges, and the power grid side meets the vehicle's charging needs.

[0108] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. An energy control strategy for bidirectional demand response in energy storage electric vehicle charging stations, characterized in that, This includes the judgment conditions required for the control flow and the commands to be executed by the control flow: The control process requires the following judgment conditions: whether there is vehicle charging; peak, valley, and normal periods, and the electricity price during these periods: peak electricity price period is T_peak, normal electricity price period is T_normal, and valley electricity price period is T_valley; whether there is an emergency demand from the external power grid; the battery's charge status, including maximum charge state (SOCmax), maximum discharge depth capacity (SOCmin), discharge warning capacity (SOC warning), and maximum battery discharge power (Pbatmax); a comparison between the vehicle charging demand power, the battery's maximum discharge power, and the maximum power input from the power grid to the charging station; the charging station's charging load ∑Pi; the charging station has multiple individual charging piles, which are electric vehicle charging terminals, including charging terminals with built-in charging modules and charging terminals without charging modules; the individual charging pile's charging load Pi; the power grid input power is Pin; and the maximum power grid input power is Pinmax; the constraint condition is: Pi <Pinmax<Pbatmax,∑Pi ≤Pbatmax; The commands required to be executed in the control flow include the following steps: S1. When there is no vehicle charging and no emergency demand from the external power grid, the battery state capacity SOCt is less than the maximum charging state SOCmax, and the time is during the off-peak electricity price period T ∈ [T_valley]. Alternatively, when there is no vehicle charging and no urgent external grid demand, the battery state capacity SOCt is less than the warning state capacity SOC warning. If the time is during the flat price and off-peak price period T ∈ [Tflat, TVolume], the battery is charged. The grid side charges the battery with the maximum input power Pinmax, i.e., P=Pinmax. S2. When there is a vehicle charging and no emergency demand from the external power grid, the maximum discharge depth capacity SOCmin ≤ battery state capacity SOCt ≤ warning state capacity SOC warning, the electric vehicle charging power Pi is not greater than the maximum input power Pinmax on the grid side, and the time is during the flat and valley electricity price periods T ∈ [T flat, T valley]. Alternatively, when there is vehicle charging and no urgent external grid demand, if the warning state capacity SOC warning < battery state capacity SOCt < maximum charging state SOCmax, the electric vehicle charging power Pi is not greater than the grid side's maximum input power Pinmax, and the time is during the off-peak electricity price period T ∈ [Tvalley], the battery is charged, and the grid side supplies power to the charging station at the maximum input power. After the electric vehicle is charged, the remaining power is used to charge the battery; charging power P = Pinmax - Pi; S3. When there is a vehicle charging and no emergency demand from the external power grid, the battery state capacity SOCt is equal to the maximum depth of discharge capacity SOCmin. When the electric vehicle charging power Pi is greater than the maximum input power Pinmax on the grid side, the battery neither charges nor discharges. The grid side charges the electric vehicle with the maximum input power Pi=Pinmax. The grid meets the charging supply Pi-1 in the previous inspection cycle. The remaining power is evenly distributed to the subsequent charging users, and the electricity price discount measures are given to the subsequent low-power charging users. S4. When there is a vehicle charging and no emergency demand from the external power grid, the battery state capacity SOCt is greater than the warning state capacity SOC warning, and the time is during the peak and flat electricity price periods T∈[Tflat, Tpeak]. Alternatively, when there is vehicle charging and no urgent external power grid demand, the battery state capacity SOCt ≤ warning state capacity SOC warning, and the time is during the peak electricity price period T∈[Tpeak], the battery discharges, and the discharge power is equal to the vehicle charging power; that is, P=Pi; S5. When there is no vehicle charging and there is an emergency demand from the external power grid, the battery state capacity SOCt is greater than the maximum depth of discharge capacity SOCmin, and the grid demand load P grid demand ≤ Pinmax, the battery discharges, and the discharge power is equal to the grid demand power; that is, P = P grid demand. S6. When there is no vehicle charging and there is an emergency demand from the external power grid, the battery state capacity SOCt is greater than the maximum depth of discharge capacity SOCmin, and the grid demand load P grid demand > Pinmax, the battery discharges, and the discharge power is equal to the maximum input power on the grid side; that is, P = Pinmax. S7. When there is vehicle charging and no emergency demand from the external power grid, the maximum discharge depth capacity SOCmin < battery state capacity SOCt ≤ warning state capacity SOC warning, and the time is during the flat and valley electricity price period T∈[Tflat, Tvalley], and the vehicle charging load Pi> Pinmax. Alternatively, when there is a vehicle charging and no urgent external grid demand, the battery state capacity SOCt > the warning state capacity SOC warning occurs during off-peak electricity price periods T ∈ [T_valley], and the vehicle charging load Pi > Pinmax. In this case, the battery discharges and charges the vehicle simultaneously with the grid. The discharge power is equal to the vehicle charging power minus the maximum input power on the grid side; that is, P = Pi - Pinmax. S8. When there is a vehicle charging and an emergency demand from the external power grid, if the battery's state capacity (SOCt) > maximum depth of discharge capacity (SOCmin), the required power supply from the grid (Pgrid) ≤ Pinmax, and the sum of the required power supply from the grid (Pgrid) and the vehicle charging power (Pi) is not greater than the battery's maximum discharge power (Pbatmax), the battery discharges, and the discharge power equals the sum of the vehicle charging power and the required power supply from the grid; that is, P = Pgrid + Pi. S9. When there is a vehicle charging and an emergency demand from the external power grid, the battery's state capacity (SOCt) > maximum depth of discharge capacity (SOCmin), the power required by the grid (Pgrid_required) > Pinmax, and the sum of the power required by the grid (Pinmax) and the vehicle charging power (Pi) is not greater than the battery's maximum discharge power (Pbatmax), the battery discharges, and the discharge power is equal to the sum of the vehicle charging power and the maximum input power from the grid; that is, P = Pbatmax + Pi. S10. When there is a vehicle charging and an emergency demand from the external power grid, the battery state capacity SOCt > the maximum depth of discharge capacity SOCmin, the power required by the power grid P_grid_required > Pinmax, and the sum of the power required by the power grid Pinmax and the vehicle charging power Pi is greater than the battery's own maximum discharge power P_batmax. Alternatively, when there is vehicle charging and an emergency demand from the external power grid, if the battery's state capacity (SOCt) > maximum depth of discharge (SOCmin), the required power supply from the grid (Pgrid) must be ≤ Pinmax, and the sum of the required power supply from the grid (Pgrid) and the vehicle charging power (Pi) must be greater than the battery's maximum discharge power (Pbatmax), then the battery will discharge at its maximum power. The discharge power P = Pbatmax. While satisfying vehicle charging needs, the battery will also maximize its ability to supply power to the external grid, with the external grid power being Pbatmax - Pi. S11. When there is no vehicle charging and no emergency demand from the external power grid, the battery state capacity SOCt ≤ the warning state capacity SOC warning, and the time is during the peak electricity price period T∈[Tpeak]. Alternatively, when there is no vehicle charging and there is an urgent demand from the external power grid, if the battery state capacity SOCt ≤ the warning state capacity SOC warning, the battery will neither charge nor discharge, and will remain in the previous inspection state, without responding to the demand from the power grid. S12. When there is a vehicle charging and an emergency demand from the external power grid, the battery state capacity SOCt equals the maximum depth of discharge capacity SOCmin. The battery will neither charge nor discharge, the power station will suspend operation, and the charging user will be notified. S13. When there is a vehicle charging and no emergency demand from the external power grid, the battery state capacity SOCt is equal to the maximum depth of discharge capacity SOCmin, the vehicle charging power Pi is not greater than the maximum input power Pinmax on the grid side, and the time is during the peak electricity price period T∈[Tpeak]. Alternatively, when there is a vehicle charging available and there is no urgent need for external power grid connection, the battery state capacity (SOCt) equals the maximum state of charge. SOCmax means that the vehicle charging power Pi is not greater than the grid's maximum input power Pinmax. When the time is during the off-peak electricity price period T∈[Tpeak], the battery neither charges nor discharges, and the grid meets the vehicle charging demand, i.e., Pin=Pi.

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