An energy management and electricity price response combined scheduling method containing energy storage charging stations

Abstract

This invention belongs to the field of energy management technology for charging stations and discloses a joint scheduling method for energy management and electricity price response of charging stations with energy storage. The method acquires information on incoming power supply capacity, station basic load, energy storage unit operating status, charging terminal operating status, vehicle energy replenishment demand, and demand response, determining the demand response period and recovery period. Based on the station-level direct replenishment capacity without relying on energy storage units during the recovery period, it determines the maximum direct replenishment capacity, response-reserved replenishment energy, and response-transferred replenishment energy for each vehicle waiting to be charged. Furthermore, it determines the station-level minimum charging demand during the demand response period, the energy storage unit's recovery-reserved capacity, and the reduction boundaries on the vehicle side and energy storage side, generating a joint scheduling instruction, and replenishing the reduced replenishment energy during the recovery period. This method is applicable to demand response and energy replenishment scheduling of charging stations with energy storage.

Description

Technical Field

[0001] This invention belongs to the field of energy management technology for charging stations, specifically a method for joint scheduling of energy management and electricity price response for charging stations with energy storage. Background Technology

[0002] With the continuous growth of electric vehicle ownership, charging stations equipped with energy storage units are gradually becoming an important application for grid-side load regulation, in-station energy management, and orderly vehicle charging. These charging stations typically include an incoming power supply unit, an energy storage unit, and multiple charging terminals. During operation, they are affected by external factors such as time-of-use pricing and demand response commands, as well as by in-station conditions such as the number of vehicles connected, the expected departure time of vehicles, terminal power supply capacity, and station basic load. Therefore, charging stations not only need to complete vehicle charging at different times, but also need to take into account the power distribution within the station and the grid-side response requirements. The overall operation has obvious time-relatedness and coupling.

[0003] In existing technologies, the scheduling and control of charging stations with energy storage typically allocates vehicle charging power and energy storage charging / discharging power based on the vehicle's current state of charge, target energy replenishment demand, expected departure time, real-time load within the station, and energy storage state of charge. In demand response scenarios, the power obtained by the charging station from the grid is often reduced by decreasing the charging power of some vehicles, limiting the total charging load within the station, or utilizing energy storage units to discharge and bear part of the load, in order to meet load limits or reduce targets during the response period. Some solutions also arrange for replenishment after the response ends, transferring the previously reduced replenishment energy to subsequent periods for completion.

[0004] However, the energy reduced during the demand response period does not disappear. Instead, it forms a continuous constraint relationship with the remaining power supply capacity during the recovery period, the available output capacity of the charging terminal, the vehicle departure time limit, and the subsequent adjustable capacity of the energy storage. If the existing dispatch control only focuses on the immediate voltage reduction effect during the demand response period, or handles the front-end reduction and the back-end replenishment separately, without coordinating the constraints on the directly replenishable energy capacity during the recovery period, the energy transferable by the vehicle, and the subsequent adjustable capacity that the energy storage unit should retain, it is easy to have a large voltage reduction during the demand response period and insufficient replenishable capacity during the recovery period. This can make it difficult for some vehicles to complete the target energy replenishment before the expected departure time, or make the remaining capacity of the energy storage unit insufficient after participating in the adjustment in the early stage. As a result, there is a lack of coherent correspondence between the demand response execution process, the energy recovery replenishment process, and the requirement for vehicles to leave on time. Summary of the Invention

[0005] The purpose of this invention is to provide a method for joint scheduling of energy management and electricity price response, including energy storage charging stations, to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a joint scheduling method for energy management and electricity price response of a charging station with energy storage, applicable to a charging station having an incoming power supply unit, an energy storage unit, and multiple charging terminals; the method first obtains the station-level operation information of the charging station, and determines the demand response period and the corresponding recovery period by combining the demand response information, and divides the demand response period and the recovery period into multiple continuous scheduling periods, so as to coordinate and analyze the charging load, energy storage regulation capacity and recovery and replenishment capacity within the station on a unified time scale.

[0007] During the recovery period, based on the incoming power supply capacity, the station's basic load, and the operating status of each charging terminal, the station-level direct replenishment capacity that the charging station can use to replenish the energy reduced during the demand response period without relying on the participation of energy storage units is first determined. Then, using this station-level direct replenishment capacity as the basic constraint for the recovery period, and combining the current state of charge of each vehicle to be charged, the target energy replenishment demand, the expected departure time, and the power supply capacity of the corresponding charging terminal, the maximum direct replenishment capacity that each vehicle to be charged can complete during the recovery period is determined, and the target energy replenishment demand of each vehicle to be charged is divided into response-reserved replenishment energy and response-transferred replenishment energy accordingly.

[0008] Among them, the response-reserved replenishment energy is the replenishment energy that the vehicle needs to complete within the demand response period in order to achieve the target replenishment energy before the expected departure time, and the response-transfer replenishment energy is the replenishment energy that is allowed to be transferred to the recovery period. By first determining the actual replenishment capacity that can be achieved within the recovery period, and then breaking down the vehicle's replenishment demand, the amount of charging that can be reduced within the demand response period can be constrained, thereby avoiding excessive reduction within the demand response period, which would result in the vehicle being unable to complete replenishment within the recovery period.

[0009] After the vehicle charging demand is broken down, the station-level minimum charging demand for each scheduling period is determined based on the energy reserve for each vehicle to be charged and the power supply capacity of the corresponding charging terminal. This station-level minimum charging demand is used to characterize the minimum charging level that can be maintained in each scheduling period under the premise that the target charging is completed before the expected departure time of the vehicle.

[0010] Furthermore, by combining the response transfer energy replenishment capability of each vehicle to be charged, the station-level direct power replenishment capability, and the current state of charge, discharge capability, and operational constraints of the energy storage unit, the amount of power to be restored and retained by the energy storage unit at the end of the demand response period is determined, and the allowable reduction range for the vehicle side and the energy storage side during the demand response period is determined.

[0011] Therefore, both vehicle-side reduction and energy storage-side adjustment are uniformly constrained by the recovery period replenishment conditions, ensuring that the reduction process during the demand response period and the replenishment process during the recovery period correspond to each other.

[0012] During the demand response period, a joint scheduling instruction is generated for the energy storage unit and each charging terminal based on the above constraints. Under the premise of not being lower than the station-level minimum charging demand for the corresponding scheduling period, the charging power corresponding to the response transfer energy replenishment is reduced first. When the vehicle side has completed the reduction but still cannot meet the demand response power reduction requirements for the current scheduling period, the energy storage unit is called to supply power to the charging terminal or the station's power supply bus to reduce the power obtained by the charging station from the grid side and bear the remaining power reduction.

[0013] By adopting the above method, load regulation during the demand response period can be completed first by using transferable vehicles to replenish energy. When the adjustment space on the vehicle side is insufficient, energy storage units can be used for supplementary regulation, thereby taking into account both demand response execution and subsequent energy replenishment and recovery.

[0014] During the recovery period, the energy that was reduced during the demand response period will be replenished based on the remaining energy to be replenished for each vehicle waiting to be charged, the expected departure time, the remaining power supply capacity after deducting the basic load of the station from the incoming power supply capacity, the power supply capacity of each charging terminal, and the remaining adjustable capacity of the energy storage unit. The total amount of replenishment will not exceed the total amount of energy that was actually reduced during the demand response period.

[0015] Therefore, the replenishment energy transferred during the demand response period can be gradually replenished during the recovery period according to the available power supply conditions, thereby ensuring a continuous technical connection between the demand response execution process and the vehicle replenishment process.

[0016] In this invention, the station-level operation information includes the available capacity of the incoming transformer, the demand response load limit, the station's basic load, the current state of charge of the energy storage unit, the rated capacity of the energy storage unit, the chargeable power of the energy storage unit, the dischargeable power of the energy storage unit, the safe lower limit of the energy storage unit, the connection status of each charging terminal, the rated output power, the currently available output power, the current state of charge of each vehicle waiting to be charged, the target energy replenishment amount or target state of charge, the expected departure time, and the electricity price information. The demand response information includes the response start time, the response end time, and the response load limit or target power reduction. By uniformly acquiring the above information, a consistent data foundation can be provided for load adjustment during the demand response period and energy replenishment during the recovery period.

[0017] During the recovery period, the station's direct replenishment capacity at the station level, which can be used to replenish the energy reduced during the demand response period, is determined based on the incoming power supply capacity, the station's basic load, and the operating status of each charging terminal, without relying on the participation of energy storage units.

[0018] Specifically, the remaining power supply capacity after deducting the station's basic load from the incoming power supply capacity can be determined for each scheduling period within the recovery period. Then, combined with the power supply capacity of each charging terminal in the corresponding scheduling period, the recoverable power for each scheduling period can be determined. Based on the recoverable power for each scheduling period and the corresponding scheduling duration, the recoverable electricity for each scheduling period can be determined. Finally, by accumulating the recoverable electricity for each scheduling period within the recovery period, the station-level direct electricity recovery capacity without relying on energy storage units within the recovery period can be obtained.

[0019] The purpose of this setup is to first clearly define the actual available energy replenishment base during the recovery period, and then use this base to constrain the reduction space during the demand response period, so as to avoid pursuing pressure reduction alone during the demand response period and deviating from the recovery conditions.

[0020] After determining the station-level direct replenishment capacity during the recovery period, the station-level direct replenishment capacity is allocated to each vehicle waiting to be charged according to the order of expected departure time, remaining energy to be replenished, and current state of charge.

[0021] Preferably, charging can be prioritized for vehicles with earlier expected departure times; if the expected departure times are the same, charging can be prioritized for vehicles with larger remaining energy to be replenished; if both the expected departure time and remaining energy to be replenished are the same, charging can be prioritized for vehicles with lower current state of charge; at the same time, the replenishment power obtained by any vehicle in any scheduling period shall not exceed the power supply capacity of its corresponding charging terminal in that scheduling period; through the above allocation method, the station-level replenishment capacity during the recovery period can be matched with the departure time limit and energy replenishment gap of each vehicle.

[0022] Based on this, the maximum direct replenishment capacity that each vehicle can complete during the recovery period is determined by combining the current state of charge, target energy replenishment demand, expected departure time, and power supply capacity of the corresponding charging terminal for each vehicle to be charged. Accordingly, the target energy replenishment demand of each vehicle to be charged is divided into response-reserved energy replenishment and response-transferred energy replenishment.

[0023] Specifically, for any vehicle to be charged, the target energy demand can be determined directly based on the target energy replenishment capacity, or based on the current state of charge and the target state of charge. Then, based on the vehicle's expected departure time, the duration of the recovery period, the power supply capacity of the corresponding charging terminal during the recovery period, and the station-level direct replenishment capacity allocated to the vehicle, the maximum direct replenishment capacity that the vehicle can complete during the recovery period is determined. Subsequently, the portion of the target energy demand that still needs to be completed within the demand response period after deducting the maximum direct replenishment capacity is determined as the response reserved replenishment energy, and the portion that can be completed within the recovery period is determined as the response transferred replenishment energy.

[0024] When a vehicle waiting to be charged cannot meet its target energy replenishment needs during both the demand response period and the recovery period, the vehicle can be treated as a vehicle that cannot be reduced. Through the above division, we can start from the actual replenishment conditions that can be achieved during the recovery period and then constrain the energy that can be transferred during the demand response period to prevent excessive reduction during the demand response period, which would result in the vehicle being unable to complete energy replenishment during the recovery period.

[0025] Subsequently, based on the response of each vehicle waiting to be charged, the energy reserve, the expected departure time, and the power supply capacity of the corresponding charging terminal, the minimum station-level charging demand for each scheduling period within the demand response period is determined.

[0026] Specifically, the minimum charging power that each vehicle to be charged needs to retain during each scheduling period within the demand response period can be determined first. Then, the minimum charging power that each vehicle to be charged needs to retain within the same scheduling period can be summarized to obtain the station-level minimum charging demand for that scheduling period.

[0027] Therefore, whether to continue reducing charging power during each scheduling period within the demand response period is no longer an isolated decision, but is uniformly constrained by the condition that the vehicle completes the target energy replenishment before the expected departure time.

[0028] After determining the minimum charging demand at the station level, the station's ability to directly replenish energy without relying on the energy storage unit during the recovery period is combined with the response transfer energy replenishment of each vehicle waiting to be charged, the station's ability to directly replenish energy without relying on the energy storage unit during the recovery period, and the current state of charge, discharge capacity, and safe lower limit of the energy storage unit. The recovery reserve energy that the energy storage unit should retain at the end of the demand response period is determined, and the reduction range that the vehicle side and the energy storage side can each bear during the demand response period is further determined.

[0029] Specifically, when the sum of the response transfer energy of each vehicle waiting to be charged is greater than the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the difference between the two can be determined as the restored reserve energy; when the sum of the response transfer energy of each vehicle waiting to be charged is not greater than the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the restored reserve energy can be determined as zero.

[0030] Based on this, the upper limits of vehicle-side power reduction, vehicle-side electricity reduction, energy storage-side power reduction, and energy storage-side electricity reduction can be further determined. In this way, the power reduction of the vehicle side and the power adjustment of the energy storage side are uniformly constrained by the replenishment conditions and the remaining capacity of the energy storage unit during the recovery period, so that the reduction process during the demand response period and the replenishment process during the recovery period are connected.

[0031] During the demand response period, provided that the charging power of each vehicle waiting to be charged is not lower than the minimum charging demand at the station level during the corresponding scheduling period, the charging power corresponding to the energy transfer and replenishment can be reduced or delayed first, and for vehicles that cannot be reduced, charging can be maintained according to the power supply capacity of the corresponding charging terminal; when there is still a difference in response power after the vehicle side has completed the reduction, the energy storage unit can be called to discharge.

[0032] After the energy storage unit discharges, it can supply power to the charging terminal or the power supply bus in the station to reduce the power obtained by the charging station from the grid side and bear the remaining power reduction. By adopting the above execution sequence, the transferable vehicle energy can be used first to meet the demand response requirements. When the vehicle-side adjustment space is insufficient, the energy storage unit can be used for supplementary adjustment, thus taking into account both demand response execution and subsequent energy replenishment and recovery.

[0033] During the recovery period, the replenishment order can be determined first according to the expected departure time of each vehicle to be charged from early to late and the remaining replenishment energy from large to small. Then, under the premise of meeting the remaining power supply capacity of the incoming line, the power supply capacity of the charging terminal, and the remaining adjustable capacity of the energy storage unit in the corresponding scheduling period, the replenishment energy reduced during the demand response period can be replenished, and the total replenishment amount shall not exceed the total replenishment energy actually reduced during the demand response period. When there are multiple replenishment periods that meet the above constraints, the replenishment period with the lower electricity price can be selected first, based on meeting the above technical constraints.

[0034] Therefore, the energy transferred during the demand response period can be gradually replenished during the recovery period in combination with available power supply conditions, forming a continuous technical closed loop between the demand response execution process and the vehicle energy replenishment process.

[0035] When new vehicle access, early departure of vehicle, change in vehicle's current state of charge, change in charging terminal's power supply capacity, change in incoming power supply capacity, change in energy storage unit's discharge capacity, change in demand response information, or change in electricity price information are detected, the station-level direct replenishment capacity without relying on energy storage units during the recovery period can be re-determined based on the changed station-level operation information, the maximum direct replenishment capacity of each vehicle waiting to be charged during the recovery period, the response-reserved replenishment energy of each vehicle waiting to be charged, the response-transferred replenishment energy of each vehicle waiting to be charged, the station-level minimum charging demand for each scheduling period during the demand response period, the recovery-reserved power capacity that the energy storage unit should retain at the end of the demand response, and the reduction range that the vehicle side and the energy storage side can each bear, and the joint dispatch instructions are updated accordingly.

[0036] This dynamic adjustment method ensures that the scheduling process remains consistent with the actual operating status of the charging station, thereby improving the matching degree between the demand response execution process and the energy restoration process.

[0037] The beneficial effects of this invention are as follows: 1. This invention first determines the station-level direct replenishment capacity without relying on energy storage units based on the incoming power supply capacity, station base load, and operating status of each charging terminal during the recovery period. Then, based on this station-level direct replenishment capacity, the target energy replenishment demand of each vehicle to be charged is broken down, distinguishing vehicle energy replenishment demand into response-reserved energy replenishment that must be completed during the demand response period and response-transfer energy replenishment that can be transferred to the recovery period. By starting from the actual replenishable conditions in the recovery phase and then constraining the reduction range in the demand response phase, the reduction action in the demand response period is no longer disconnected from the subsequent replenishment process, thereby reducing the situation where the voltage drop is too large during the demand response period and the vehicle energy replenishment cannot be completed during the recovery period, and improving the matching between the charging station's execution of demand response and completion of vehicle energy replenishment.

[0038] 2. This invention, based on the response of each vehicle to be charged, the reserved energy, the expected departure time, and the power supply capacity of the corresponding charging terminal, further determines the minimum station-level charging demand for each scheduling period within the demand response period. On this basis, it constrains the vehicle-side reduction range and the energy storage-side adjustment range. By limiting the total charging power for each scheduling period within the demand response period to above the minimum station-level charging demand, the vehicle-side power reduction process always assumes that the vehicle completes the necessary energy replenishment before the expected departure time. Simultaneously, by maintaining charging for vehicles that cannot be reduced, it avoids including vehicles that are physically difficult to replenish in the power reduction target, thereby reducing the adverse impact of the demand response execution process on vehicles requiring emergency energy replenishment and vehicles with tight departure time limits, making the station-level scheduling process more coherent and feasible.

[0039] 3. After determining the response transfer energy of each vehicle to be charged, this invention further combines the station-level direct power replenishment capability without relying on the energy storage unit during the recovery period, as well as the current state of charge, discharge capacity, and safe lower limit of the energy storage unit, to determine the recovery reserve energy that the energy storage unit should retain at the end of the demand response. Based on this, the order of vehicle-side reduction and energy storage-side discharge is coordinated. By prioritizing the use of the transferable energy on the vehicle side to undertake the demand response, and then supplementing the remaining power reduction by the energy storage unit when the vehicle-side adjustment space is insufficient, and organizing the replenishment according to the remaining energy to be replenished and the departure time limit during the recovery phase, the early adjustment capability and subsequent recovery capability of the energy storage unit are kept connected. This reduces the situation where excessive discharge of the energy storage unit in the early stage leads to limited subsequent energy replenishment and improves the overall stability of the demand response execution process and the recovery energy replenishment process. Attached Figure Description

[0040] Figure 1 This is a flowchart illustrating the overall process of energy management and electricity price response joint scheduling of the present invention, including energy storage charging stations. Figure 2 This is a flowchart illustrating the power reduction execution process during the demand response period of this invention. Detailed Implementation

[0041] 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.

[0042] like Figures 1 to 2 As shown, this embodiment of the invention provides a joint scheduling method for energy management and electricity price response of charging stations with energy storage, applicable to charging stations with incoming power supply units, energy storage units, and multiple charging terminals; station-level operation information is composed of incoming power supply data, energy storage unit operation data, charging terminal operation data, and vehicle access data, while demand response information is provided by external demand response commands; based on the above information, the demand response period and the corresponding recovery period are first determined, and the demand response period and recovery period are divided into multiple continuous scheduling periods to analyze the load changes, energy storage regulation capacity, and recovery and replenishment process within the station at a unified time scale.

[0043] During the recovery period, the station's direct replenishment capacity at the station level, which can be used to replenish the energy reduced during the demand response period, is determined based on the incoming power supply capacity, the station's basic load, and the operating status of each charging terminal, without relying on the participation of energy storage units.

[0044] Specifically, for each scheduling period within the recovery period, the remaining power supply capacity after deducting the station's basic load from the incoming power supply capacity is first determined. Then, combined with the power supply capacity of each charging terminal in the corresponding scheduling period, the recoverable power for each scheduling period is determined. Based on the recoverable power and corresponding scheduling duration for each scheduling period, the recoverable electricity for each scheduling period is determined. Finally, the recoverable electricity for each scheduling period within the recovery period is accumulated to obtain the station-level direct electricity recovery capacity without relying on energy storage units during the recovery period.

[0045] By first determining the actual available replenishment base during the recovery period, and then implementing reduction control during the demand response period, it is possible to avoid unilaterally reducing charging power outside of the recovery conditions during the demand response period.

[0046] After determining the station-level direct replenishment capacity during the recovery period, this capacity is allocated to each vehicle waiting to be charged according to the vehicle's departure constraints and replenishment gap. Specifically, the vehicles waiting to be charged are first sorted from earliest to latest according to their expected departure time; if the expected departure times are the same, they are sorted from largest to smallest remaining replenishment energy; if both the expected departure time and remaining replenishment energy are the same, they are sorted from lowest to highest current state of charge. Following the above order, the replenishable power is allocated to each vehicle waiting to be charged in each scheduling period, and the replenishment power obtained by any vehicle waiting to be charged in any scheduling period does not exceed the power supply capacity of its corresponding charging terminal in that scheduling period. Based on the allocation results, the maximum direct replenishment capacity that each vehicle waiting to be charged can complete during the recovery period is determined.

[0047] Subsequently, the target energy demand of each vehicle to be charged is broken down based on its current state of charge, target energy replenishment demand, expected departure time, power supply capacity of the corresponding charging terminal, and the maximum direct replenishment amount after allocation. For any vehicle to be charged, the target energy replenishment demand is determined directly by the target energy replenishment amount, or by conversion between the current state of charge and the target state of charge.

[0048] The portion of the target energy replenishment demand of the vehicle to be charged that can be completed within the recovery period by the maximum direct replenishment power is determined as the response transfer energy replenishment, and the portion that still needs to be completed within the demand response period after deducting this portion is determined as the response reserved energy replenishment.

[0049] If a vehicle waiting to be charged is continuously charged at the maximum power supply capacity of the corresponding charging terminal during the demand response period, and the maximum direct replenishment power during the recovery period is added, but its target energy replenishment demand is still not met, then the vehicle waiting to be charged is determined to be a vehicle that cannot be reduced, and its charging will continue during subsequent demand response periods without any reduction in its charging power.

[0050] By adopting the above approach, we can first use the actual achievable energy replenishment conditions during the recovery period as a basis, and then conversely constrain the energy replenishment that can be transferred during the demand response period, thereby avoiding excessive reduction during the demand response period that would prevent vehicles from completing energy replenishment on time.

[0051] After the energy replenishment needs of each vehicle to be charged are broken down, the minimum station-level charging needs for each scheduling period are determined based on the energy replenishment reserved by each vehicle to be charged, the expected departure time, and the power supply capacity of the corresponding charging terminal.

[0052] Specifically, the minimum charging power that each vehicle to be charged needs to retain in each scheduling period during the demand response period is first determined. Then, the minimum charging power that each vehicle to be charged needs to retain in the same scheduling period is summarized to obtain the station-level minimum charging demand for that scheduling period. Thus, the reduction of charging power in each scheduling period during the demand response period is based on the premise of not being lower than the station-level minimum charging demand, thereby ensuring that the basic condition for vehicles to complete the target energy replenishment before the expected departure time is not compromised.

[0053] Based on this, and considering the response-transfer energy replenishment capacity of each vehicle waiting to be charged, the station-level direct replenishment capacity without relying on energy storage units during the recovery period, and the current state of charge, discharge capacity, and safe minimum capacity of the energy storage units, the recovery reserve capacity that the energy storage units should retain at the end of the demand response is determined. Simultaneously, the reduction range that both the vehicle-side and energy storage-side can undertake during the demand response period is determined. Specifically, the reduction range on the vehicle side is constrained by both the response-transfer energy replenishment capacity and the station-level minimum charging demand, while the reduction range on the energy storage side is constrained by both the discharge capacity, safe minimum capacity, and recovery reserve capacity of the energy storage units. In this way, the power reduction on the vehicle side and the power adjustment on the energy storage side are no longer conducted in isolation, but are uniformly constrained by the replenishment conditions during the recovery period and the remaining adjustment capacity of the energy storage units, ensuring that the reduction process during the demand response period corresponds to the replenishment process during the recovery period.

[0054] During the demand response period, joint scheduling instructions for energy storage units and each charging terminal are generated based on the above constraints. Under the premise of not being lower than the station-level minimum charging demand for the corresponding scheduling period, priority is given to reducing or delaying the charging power corresponding to the energy transfer and replenishment, and charging of vehicles that cannot be reduced is maintained according to the power supply capacity of the corresponding charging terminal. When there is still a difference in response power after the vehicle side has completed the reduction, the energy storage unit is called to discharge.

[0055] After the energy storage unit discharges, it supplies power to the charging terminal or the power supply bus in the station to reduce the power obtained by the charging station from the grid side and to bear the remaining power reduction. By adopting the above execution sequence, the energy of the transferable vehicles can be used first to meet the demand response requirements, and the energy storage unit can be used for supplementary regulation when the vehicle-side adjustment space is insufficient.

[0056] During the recovery period, the replenishment order is determined according to the expected departure time of each vehicle to be charged from early to late and the remaining energy to be replenished from large to small. Under the premise of meeting the remaining power supply capacity of the incoming line, the power supply capacity of the charging terminal, and the remaining adjustable capacity of the energy storage unit during the corresponding scheduling period, the replenishment energy reduced during the demand response period is replenished, and the total replenishment amount does not exceed the total replenishment energy actually reduced during the demand response period.

[0057] If there are multiple replenishment periods that simultaneously meet the aforementioned technical constraints, the replenishment period with the lower electricity price will be selected first, based on meeting the aforementioned technical constraints. In this way, the replenishment energy transferred during the demand response period can be gradually replenished during the recovery period according to the available power supply conditions, thereby forming a complete process that connects the demand response execution process and the vehicle replenishment recovery process.

[0058] When a new vehicle is detected joining, a vehicle leaves the station early, a change in the vehicle's current state of charge, a change in the charging terminal's power supply capacity, a change in the incoming power supply capacity, a change in the energy storage unit's discharge capacity, a change in demand response information, or a change in electricity price information, the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period is re-determined based on the changed station-level operation information. This includes the maximum direct replenishment capacity of each vehicle waiting to be charged during the recovery period, the response-reserved replenishment energy of each vehicle waiting to be charged, the response-transferred replenishment energy of each vehicle waiting to be charged, the station-level minimum charging demand for each scheduling period during the demand response period, the recovery-reserved capacity that the energy storage unit should retain at the end of the demand response, and the reduction range that the vehicle side and the energy storage side can each bear. Based on this, the joint scheduling instructions are updated to ensure that the scheduling process remains consistent with the actual operating status of the charging station.

[0059] In this embodiment, a joint scheduling method for energy management and electricity price response of a charging station with energy storage is executed by the station-level control unit of the charging station. The charging station includes an incoming power supply unit, an energy storage unit and multiple charging terminals. The incoming power supply unit is used to introduce external power grid electricity into the station's power supply bus. The energy storage unit is connected to the station's power supply bus through a bidirectional power conversion device. Each charging terminal is connected to the station's power supply bus and establishes a charging connection with the corresponding vehicle to be charged.

[0060] The station-level control unit is connected to the incoming line monitoring device, the energy storage unit control device, and each charging terminal to collect station-level operation information and generate joint dispatch instructions.

[0061] In this embodiment, the station-level operation information includes at least the following: the available capacity of the incoming transformer, the demand response limit value, the station's basic load, the current state of charge of the energy storage unit, the rated capacity of the energy storage unit, the rechargeable power of the energy storage unit, the dischargeable power of the energy storage unit, the safe lower limit of the energy storage unit, the connection status of each charging terminal, the rated output power, the currently available output power, the current state of charge of each vehicle waiting to be charged, the target energy replenishment amount or the target state of charge, the expected departure time, and the electricity price information. The incoming power supply capacity can be determined based on the available capacity of the incoming transformer, the demand response load limit, and the occupied capacity within the station. The station's basic load can be obtained by summarizing the real-time load of other electrical equipment within the station, excluding charging terminals and energy storage units. The current state of charge, chargeable power, dischargeable power, and safe lower limit of energy storage units are provided by the energy storage unit control device. The connection status, rated output power, and current available output power of each charging terminal are reported by each charging terminal. The current state of charge, target energy replenishment or target state of charge, and expected departure time of each vehicle waiting to be charged can be obtained through interaction between the vehicle and the charging terminal, or by input by the user at the start of charging and confirmed by the station-level control unit.

[0062] Demand response information is issued by an external demand response platform, load aggregation platform, or grid dispatching side, and includes at least the response start time, response end time, and response load limit or target power reduction. After receiving the demand response information, the station-level control unit divides the demand response period and its corresponding recovery period into multiple continuous dispatch periods. The duration of each dispatch period can be preset and kept consistent according to the station's dispatching accuracy requirements, so as to handle the charging load reduction and recovery replenishment issues on a unified time scale.

[0063] During the recovery period, the station-level control unit first determines the station-level direct power replenishment capacity without relying on the energy storage unit. In specific implementation, for each scheduling period within the recovery period, the remaining power supply capacity after deducting the station's basic load from the incoming power supply capacity within that scheduling period is first determined. Then, combined with the current available output power of each charging terminal within that scheduling period, the replenishable power within that scheduling period is determined.

[0064] The recoverable power is taken as the smaller value between the remaining power supply capacity and the total power supply capacity of each charging terminal, so as to ensure that the recovery process during the recovery period does not exceed the power supply capacity that the incoming side can provide, nor does it exceed the actual charging capacity that the terminal side can output.

[0065] Subsequently, the station-level control unit determines the recoverable power for the scheduling period based on the recoverable power and the corresponding scheduling duration, and accumulates the recoverable power for all scheduling periods within the recovery period to obtain the station-level direct power recovery capability without relying on energy storage units during the recovery period.

[0066] After obtaining the station-level direct power replenishment capability without relying on energy storage units during the recovery period, the station-level control unit allocates this power capability according to vehicle departure constraints and power replenishment gaps. Specifically, firstly, the vehicles to be charged are sorted from earliest to latest according to their expected departure time; if the expected departure time is the same, they are sorted from largest to smallest according to the remaining energy to be replenished; if both the expected departure time and the remaining energy to be replenished are the same, they are sorted from lowest to highest according to the current state of charge.

[0067] Following the above sequence, the station-level control unit allocates the recoverable power in each scheduling period during the recovery period, and ensures that the recoverable power obtained by any vehicle to be charged in any scheduling period does not exceed the current available output power of its corresponding charging terminal in that scheduling period; based on the allocation results of each scheduling period, the maximum direct recoverable power that each vehicle to be charged can complete in the recovery period is accumulated.

[0068] After obtaining the maximum direct replenishment capacity of each vehicle to be charged, the station-level control unit further determines the target replenishment demand of each vehicle to be charged. For vehicles that use the target replenishment capacity as the control target, the target replenishment capacity can be directly used as the target replenishment demand. For vehicles that use the target state of charge as the control target, the target replenishment demand can be calculated based on the current state of charge, the available battery capacity of the vehicle, and the target state of charge.

[0069] Subsequently, the target energy replenishment demand of each vehicle to be charged is compared with its maximum direct replenishment capacity: the portion of energy replenishment demand that can be completed within the recovery period using the maximum direct replenishment capacity is determined as response transfer energy replenishment; the portion that still needs to be completed within the demand response period after deducting this portion is determined as response reserved energy replenishment.

[0070] In this embodiment, a rule for identifying and processing non-adjustable vehicles is also set; for any vehicle to be charged, the station-level control unit will also calculate the maximum energy replenishment that the vehicle to be charged can complete when continuously charging according to the maximum power supply capacity of its corresponding charging terminal during the demand response period.

[0071] If the sum of the maximum energy replenishment that the vehicle can complete during the demand response period and the maximum direct replenishment energy it can complete during the recovery period is still less than the target energy replenishment requirement of the vehicle, it means that even if the vehicle is charged at its maximum allowable capacity during both the demand response period and the recovery period, it will not be able to complete the target energy replenishment before the expected departure time.

[0072] For this type of vehicle, the station-level control unit identifies it as a non-reducible vehicle, sets its response transfer energy to zero, and sets its response retention energy to the maximum energy that the vehicle can replenish during the demand response period.

[0073] During subsequent demand response execution, vehicles that cannot be reduced will continue to be supplied with power according to the power supply capacity of their corresponding charging terminals during the current scheduling period and the minimum charging demand that the vehicle needs to maintain, and will no longer participate in vehicle-side power reduction.

[0074] After completing the division of response-retained energy replenishment and response-transfer energy replenishment, the station-level control unit further determines the station-level minimum charging demand for each scheduling period within the demand response period.

[0075] In practice, for each vehicle waiting to be charged, the station-level control unit calculates the minimum charging power that the vehicle needs to maintain in each scheduling period during the demand response period based on the vehicle's response-reserved replenishment energy, the expected departure time, and the current available output power of the corresponding charging terminal. Then, the minimum charging power of all vehicles waiting to be charged in the same scheduling period is summarized to obtain the station-level minimum charging demand for that scheduling period.

[0076] Therefore, any power reduction action on the vehicle side during the demand response period must not cause the total charging power during that scheduling period to be lower than the station's minimum charging demand.

[0077] Subsequently, the station-level control unit first combines the response transfer energy replenishment of each vehicle to be charged, the station-level direct power replenishment capability without relying on the energy storage unit during the recovery period, and the current state of charge, discharge capacity, and safe lower limit of the energy storage unit to determine the recovery reserve power that the energy storage unit should retain at the end of the demand response.

[0078] Specifically, when the sum of the response transfer energy of each vehicle waiting to be charged is greater than the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the difference between the two is the replenishment energy that still needs to be compensated by the energy storage unit during the recovery period, and the difference is determined as the recovery reserve energy; when the sum of the response transfer energy of each vehicle waiting to be charged is not greater than the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the recovery reserve energy is determined to be zero.

[0079] Based on this, the station-level control unit further determines the reduction range that the vehicle side and the energy storage side can each undertake during the demand response period; among them, the reduction range of the vehicle side is jointly constrained by the response transfer energy replenishment of each vehicle waiting to be charged and the station-level minimum charging demand of each scheduling period during the demand response period; the reduction range of the energy storage side is jointly constrained by the discharge capacity of the energy storage unit, the safe lower limit of the power, and the restored reserved power.

[0080] During the demand response period, the station-level control unit generates joint scheduling instructions for energy storage units and each charging terminal based on the above analysis results. In specific execution, firstly, under the premise of not being lower than the station-level minimum charging demand during the current scheduling period, the charging power corresponding to the response transfer energy replenishment of each vehicle to be charged is preferentially reduced or postponed. For vehicles that have been determined to be non-reducible, charging is maintained according to the power supply capacity of their corresponding charging terminal during the current scheduling period and the minimum charging demand that the vehicle needs to maintain, and they do not participate in the vehicle-side reduction.

[0081] If, after the vehicle-side reduction is completed, the total power reduction at the station level is still lower than the demand response power reduction requirement for the current scheduling period, the station-level control unit will further call the energy storage unit to discharge. The demand response power reduction requirement for the current scheduling period can be directly determined by the target power reduction, or by the difference between the response load limit and the original load in the station during the scheduling period. After the energy storage unit supplies power to the charging terminal or the station's power supply bus via a bidirectional power conversion device, a portion of the electrical energy required by the charging terminal in the station is borne by the energy storage unit. Therefore, the power obtained by the charging station from the grid side is reduced accordingly, and the unmet power reduction difference is thus made up.

[0082] During the recovery period, the station-level control unit organizes the energy recovery process based on the actual energy reduction during the demand response period. Specifically, the recovery order is first determined according to the expected departure time of each vehicle to be charged from early to late and the remaining energy to be replenished from large to small. Then, under the premise of meeting the remaining power supply capacity of the incoming line during the corresponding scheduling period, the current available output power of the charging terminal, and the remaining adjustable capacity of the energy storage unit, the energy reduction during the demand response period is replenished, and the total amount of energy replenished during the recovery period does not exceed the total amount of energy actually reduced during the demand response period.

[0083] When there are multiple optional replenishment periods that simultaneously meet the above technical constraints, the station-level control unit can further combine electricity price information and prioritize the dispatching period with the lower electricity price to arrange replenishment, while meeting the aforementioned technical constraints.

[0084] Furthermore, in this embodiment, the station-level control unit can also dynamically track changes in the charging station's operating status. When it detects new vehicle access, early vehicle departure, changes in the vehicle's current state of charge, changes in the charging terminal's current available output power, changes in the incoming power supply capacity, changes in the energy storage unit's discharge capacity, changes in demand response information, or changes in electricity price information, the station-level control unit, based on the changed station-level operating information, redetermines the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the maximum direct replenishment capacity of each vehicle waiting to be charged during the recovery period, the response-reserved replenishment energy of each vehicle waiting to be charged, the response-transferred replenishment energy of each vehicle waiting to be charged, the station-level minimum charging demand for each scheduling period during the demand response period, the recovery-reserved capacity that the energy storage unit should retain at the end of the demand response, and the reduction range that the vehicle side and the energy storage side can each bear, and updates the joint scheduling instructions accordingly. This ensures that the joint scheduling process remains consistent with the actual operating status of the charging station.

[0085] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0086] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for joint scheduling of energy management and electricity price response, including an energy storage charging station, characterized in that: The method, applicable to a charging station having an incoming power supply unit, an energy storage unit, and multiple charging terminals, includes: Obtain station-level operation information of charging stations; Determine the demand response period and the recovery period corresponding to the demand response period based on the demand response information, and divide the demand response period and the recovery period into multiple consecutive scheduling periods; Based on the incoming power supply capacity, station base load and the operating status of each charging terminal during the recovery period, determine the station-level direct power replenishment capacity without relying on energy storage units during the recovery period. Based on the current state of charge, target energy replenishment demand, expected departure time, power supply capacity of the corresponding charging terminal, and the station-level direct energy replenishment capacity of each vehicle to be charged, the maximum direct energy replenishment capacity of each vehicle to be charged during the recovery period is determined. Based on the target energy replenishment demand and maximum direct energy replenishment capacity of each vehicle to be charged, the response-retained energy replenishment and response-transferred energy replenishment of each vehicle to be charged are determined. Based on the energy reserve of each vehicle waiting to be charged and the power supply capacity of the corresponding charging terminal, the minimum station-level charging demand for each scheduling period within the demand response period is determined. Based on the response transfer energy replenishment of each vehicle to be charged, the station-level direct power replenishment capability, and the operating status of the energy storage unit, determine the amount of power to be restored and retained by the energy storage unit at the end of the demand response period, as well as the reduction boundaries of the vehicle side and the energy storage side during the demand response period. Based on the restored and reserved power and the reduction boundary, a joint scheduling instruction is generated between the energy storage unit and each charging terminal. Under the premise of not being lower than the station-level minimum charging demand in the corresponding scheduling period, the charging power corresponding to the response transfer energy is reduced. When the reduced power on the vehicle side is still less than the demand response reduction power requirement in the current scheduling period, the energy storage unit is called to supply power to the charging terminal or the station power supply bus to reduce the power obtained by the charging station from the grid side and provide the remaining reduced power. During the recovery period, the energy that was reduced during the demand response period will be replenished based on the remaining energy to be replenished for each vehicle waiting to be charged, the expected departure time, the remaining power supply capacity after deducting the basic load of the station from the incoming power supply capacity, the power supply capacity of each charging terminal, and the remaining adjustable capacity of the energy storage unit. The total amount of replenishment shall not exceed the sum of the energy that was reduced for each vehicle waiting to be charged during the demand response period.

2. The method for joint scheduling of energy management and electricity price response including an energy storage charging station according to claim 1, characterized in that: The station-level operation information includes the available capacity of the incoming transformer, the demand response limit, the station's basic load, the current state of charge of the energy storage unit, the rated capacity of the energy storage unit, the rechargeable power of the energy storage unit, the dischargeable power of the energy storage unit, the safe lower limit of the energy storage unit, the connection status of each charging terminal, the rated output power, the currently available output power, the current state of charge of each vehicle waiting to be charged, the target energy replenishment amount or the target state of charge, the expected departure time, and the electricity price information. The demand response information includes the response start time, response end time, and response load limit or target power reduction.

3. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 2, characterized in that: The station-level direct power replenishment capability during the recovery period without relying on energy storage units is determined as follows: For each scheduling period within the recovery period, determine the remaining power supply capacity after deducting the station's basic load from the incoming power supply capacity; For each scheduling period within the recovery period, the recoverable power is determined by the remaining power supply capacity of the corresponding scheduling period and the power supply capacity of each charging terminal in the corresponding scheduling period. For each scheduling period within the recovery period, the product of the recoverable power and the corresponding scheduling duration is determined as the recoverable power for the corresponding scheduling period; The replenishable power for each scheduling period within the recovery period is accumulated to obtain the station-level direct replenishment power capability without relying on energy storage units during the recovery period.

4. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 3, characterized in that: The process of determining the maximum direct replenishment capacity of each vehicle to be charged during the recovery period, and determining the response-reserved replenishment capacity and response-transferred replenishment capacity of each vehicle to be charged based on the target replenishment demand and maximum direct replenishment capacity of each vehicle to be charged, includes: For any vehicle to be charged, the target energy demand is determined based on its target energy replenishment capacity, or based on its current state of charge and target state of charge. Based on the expected departure time of the vehicle to be charged, the duration of the recovery period, the power supply capacity of the corresponding charging terminal during the recovery period, and the station-level direct replenishment capacity that can be allocated to the vehicle to be charged during the recovery period, the maximum direct replenishment capacity that the vehicle to be charged can complete during the recovery period is determined. The minimum energy replenishment required by the vehicle to be charged during the demand response period is obtained by subtracting the maximum direct replenishment capacity from the target energy replenishment demand, and the minimum energy replenishment capacity is determined as the response reserved energy replenishment capacity. The portion of the target energy replenishment demand that exceeds the energy replenishment energy reserved in the response is determined as the energy replenishment energy transferred in the response. When the target energy replenishment demand is greater than the sum of the maximum energy replenishment that the vehicle to be charged can complete during the demand response period and the maximum direct replenishment energy, the vehicle to be charged is determined as a non-reducible vehicle, the response transfer energy of the vehicle to be charged is determined to be zero, and the response retention energy of the vehicle to be charged is determined to be the maximum energy replenishment that the vehicle to be charged can complete during the demand response period.

5. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 4, characterized in that: The station-level direct replenishment capacity that can be allocated to any vehicle waiting to be charged during the recovery period is determined according to the following rules: Priority will be given to vehicles waiting to be charged that are expected to depart earlier; When the expected departure times are the same, priority will be given to vehicles with a larger remaining energy to be replenished. When the expected departure time and remaining energy to be replenished are the same, priority will be given to vehicles waiting to be recharged with lower current state of charge. Provided that the aforementioned allocation order is met, the replenishment power obtained by any vehicle to be charged in any scheduling period shall not exceed the power supply capacity of the charging terminal corresponding to the vehicle to be charged in that scheduling period.

6. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 5, characterized in that: The minimum charging demand at the station level for each scheduling period within the demand response period is determined as follows: Based on the response energy retention of each vehicle waiting to be charged, the expected departure time, and the power supply capacity of the corresponding charging terminal, determine the minimum charging power that each vehicle waiting to be charged needs to retain during each scheduling period within the demand response period. The minimum charging power that each vehicle waiting to be charged needs to retain during the same scheduling period is summarized to obtain the station-level minimum charging demand for that scheduling period.

7. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 6, characterized in that: The amount of energy that the energy storage unit should retain upon the end of the demand response is determined as follows: When the sum of the response transfer energy of each vehicle to be charged is greater than the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the difference between the two is determined as the recovered reserved energy. When the sum of the response transfer energy of each vehicle to be charged is not greater than the station-level direct power replenishment capacity without relying on the energy storage unit during the recovery period, the recovered reserved power is determined to be zero.

8. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 7, characterized in that: The reduction boundaries for both the vehicle-side and energy storage-side during the demand response period are determined as follows: During any scheduling period within the demand response period, the upper limit of the vehicle-side power reduction is the sum of the charging power that can be reduced for each vehicle waiting to be charged, provided that it is not lower than the station-level minimum charging demand during that scheduling period. The upper limit of the vehicle-side power reduction is the smaller of the sum of the response transfer energy of each vehicle waiting to be charged and the station-level direct power replenishment capacity without relying on energy storage units during the recovery period. The upper limit of the power reduction on the energy storage side is the power that the energy storage unit can release under the constraints of meeting the safety lower limit of power and restoring the reserved power. The upper limit of the energy storage side's power reduction is the amount of energy that the energy storage unit can release under the constraints of meeting the safety lower limit power and restoring the reserved power.

9. The energy management and electricity price response joint scheduling method including an energy storage charging station according to claim 8, characterized in that: The execution methods of the joint scheduling instructions include: During the demand response period, the charging power corresponding to the energy transfer of each vehicle waiting to be charged is first reduced or delayed, and the power supply to vehicles that cannot be reduced is continuously supplied according to the power supply capacity of the corresponding charging terminal. If a power difference still exists, the energy storage unit is activated to discharge. During the recovery period, the replenishment order is determined first according to the expected departure time of each vehicle to be charged from early to late and the remaining energy to be replenished from large to small. Then, the replenishment is completed on the premise of meeting the remaining power supply capacity of the incoming line, the power supply capacity of the charging terminal, and the remaining adjustable capacity of the energy storage unit during the corresponding scheduling period. When there are multiple replenishment periods that meet the aforementioned constraints, the replenishment period with the lower electricity price should be selected first.

10. The method for joint scheduling of energy management and electricity price response including an energy storage charging station according to claim 9, characterized in that: When a new vehicle is detected joining, a vehicle leaves the station early, a change in the current state of charge of a vehicle, a change in the power supply capacity of the charging terminal, a change in the power supply capacity of the incoming line, a change in the discharge power of the energy storage unit, a change in demand response information, or a change in electricity price information, the station-level direct replenishment capacity without relying on the energy storage unit during the recovery period, the maximum direct replenishment capacity of each vehicle waiting to be charged during the recovery period, the response-reserved replenishment energy of each vehicle waiting to be charged, the response-transferred replenishment energy of each vehicle waiting to be charged, the station-level minimum charging demand for each scheduling period during the demand response period, the recovery-reserved capacity that the energy storage unit should retain at the end of the demand response, and the reduction boundaries on the vehicle side and the energy storage side are updated, and the joint scheduling instructions are updated.

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