Regulation and control method and system for virtual power plant participating in frequency modulation of battery swap station

Abstract

The invention discloses a regulation and control method and system for a virtual power plant of a battery swap station to participate in frequency modulation, and the method comprises the steps: aggregating a plurality of dispersed battery swap stations into a virtual power plant, adding the virtual power plant into a provincial power grid master station AGC system, and carrying out the bidirectional data interaction; and the virtual power plant aggregation platform adopts a multi-target optimization model to perform power distribution according to the power grid demand and the battery swap station operation demand, and each battery swap station receives an instruction and accurately executes charging and discharging operation through a power converter. According to the method, power grid auxiliary frequency modulation and battery swap station operation constraints can be considered, the power grid adjustment flexibility and the new energy consumption capability are improved, and the stability and the economical efficiency of power grid operation are enhanced while the user service and the commercial value of the battery swap station are ensured.

Description

Technical Field

[0001] This invention relates to the field of power frequency control and smart grid technology, and in particular to a control method and system for frequency regulation involving a virtual power plant at a battery swapping station. Background Technology

[0002] With the advancement of the "dual carbon" target, the penetration rate of new energy sources, represented by wind power and photovoltaics, in the power grid is constantly increasing. The randomness and volatility of their output pose a significant challenge to the frequency stability of the power grid. Traditional frequency regulation of the power grid mainly relies on the automatic generation control systems of conventional generating units such as thermal power and hydropower. However, the frequency regulation capability of conventional units is limited, and their response speed is relatively slow, making it difficult to fully meet the rapid frequency regulation requirements under the high proportion of new energy integration.

[0003] Electric vehicle battery swapping stations, as a new type of distributed energy resource, are typically equipped with energy storage battery clusters of considerable capacity. These battery clusters possess millisecond-level fast charge and discharge power response capabilities, making them a high-quality frequency regulation resource. However, the capacity of a single battery swapping station is relatively small, preventing it from directly participating in grid-level frequency regulation services. Therefore, how to effectively aggregate a large number of dispersed battery swapping stations within a region to construct a virtual power plant with large-scale frequency regulation capabilities, and design a control method that can coordinate and interact with the provincial power grid master station's AGC system while balancing grid frequency regulation needs and the operational constraints of the battery swapping stations themselves, has become an urgent technical problem to be solved. Summary of the Invention

[0004] Purpose of the invention: The purpose of this invention is to provide a control method and system for a virtual power plant of a battery swapping station to participate in frequency regulation. By aggregating dispersed battery swapping station resources through a virtual power plant aggregation platform and designing a multi-mode collaborative control strategy, the system enables the station to participate in grid frequency regulation safely, reliably, and efficiently, thereby expanding grid frequency regulation resources and improving grid frequency control quality and renewable energy absorption capacity.

[0005] Technical solution: The present invention provides a method for frequency regulation involving a virtual power plant at a battery swapping station, comprising the following steps:

[0006] Aggregate several battery swapping stations into a virtual power plant;

[0007] The virtual power plant reports AGC controllable signals, active frequency modulation participation signals, and joint frequency modulation participation signals to the provincial power grid master station;

[0008] The provincial power grid master station outputs power grid frequency regulation control commands to the virtual power plants based on the signals reported by the virtual power plants. The power grid frequency regulation control commands include control mode commands, and the control modes include local mode, active frequency regulation mode and joint frequency regulation mode.

[0009] When the virtual power plant's control mode is active frequency regulation mode, the virtual power plant participates in the primary frequency regulation of the power grid; when the virtual power plant's control mode is joint frequency regulation mode, the virtual power plant participates in the secondary frequency regulation of the power grid; when the virtual power plant's control mode is local mode, the provincial power grid master station does not issue power grid frequency regulation control commands to the virtual power plant.

[0010] The AGC controllable signal is used to inform the provincial power grid master station virtual power plant whether it has the ability to receive and execute AGC commands; the active frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the primary frequency regulation of the power grid; the joint frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the secondary frequency regulation of the power grid.

[0011] Furthermore, when the control mode of the virtual power plant is active frequency regulation mode, if the provincial master station detects that the grid frequency deviation exceeds the set deviation threshold, it sends a start signal to the virtual power plant according to the frequency control requirements, triggering it to participate in primary frequency regulation.

[0012] When the control mode of the virtual power plant is the joint frequency regulation mode, the provincial AGC master station will treat the virtual power plant of the battery swapping station the same as the traditional generator set, and each battery swapping station in the virtual power plant will participate in the secondary frequency regulation of the power grid.

[0013] Furthermore, when the telemetry values ​​of the AGC controllable signal and the active frequency modulation participation signal sent by the virtual power plant to the provincial power grid master station are both in sync, and the telemetry data meets the first condition, the provincial power grid master station sets the virtual power plant to active frequency modulation mode according to the power grid control requirements; otherwise, it sets it to local mode. The first condition includes: the deviation between the real-time frequency telemetry value of the power grid and the rated frequency is ≥ ±0.05Hz, the telemetry value of the virtual power plant's real-time power increase / decrease limit is ≥ the regulation capacity required for primary frequency regulation, and the telemetry value of the average battery state of charge is within a safe range.

[0014] When the telemetry values ​​of the AGC controllable signal and the joint frequency regulation participation signal sent by the virtual power plant to the provincial power grid master station are both in sync, and the telemetry data meets the second condition, the provincial power grid master station sets the virtual power plant to joint frequency regulation mode according to the power grid control requirements; otherwise, it sets it to local mode. The second condition includes: the telemetry value of the regional control deviation is not equal to 0, the deviation between the telemetry value of the virtual power plant's real-time total active power and the master station's planned value is ≤5%, and the telemetry value of the actual value of the ramp rate of the battery swapping station meets the command execution requirements.

[0015] When the remote signaling value of the AGC controllable signal sent by the virtual power plant to the provincial power grid master station is "on", and the remote signaling values ​​of the active frequency modulation participation signal and the joint frequency modulation participation signal are both "off", the provincial power grid master station determines that the remote signaling value sent by the virtual power plant is abnormal, and without relying on telemetry data for additional determination, it directly sets the virtual power plant to local mode.

[0016] When the telemetry values ​​of the AGC controllable signal, active frequency modulation participation signal, and joint frequency modulation participation signal transmitted by the virtual power plant are all in sync, the provincial power grid master station determines the following based on the telemetry data: if the telemetry conditions for active frequency modulation mode are met, it is set to active frequency modulation mode; if the telemetry conditions for joint frequency modulation mode are met, it can be set to joint frequency modulation mode; if none of them are met or the need to prioritize battery swapping needs is required, it is set to local mode.

[0017] Furthermore, when the virtual power plant's control mode is active frequency regulation mode:

[0018] The provincial power grid master station continuously monitors the real-time frequency of the system; when the frequency deviation exceeds the preset threshold and continues to exceed the preset delay, the provincial power grid master station sends an active frequency regulation start signal and the frequency deviation value to the virtual power plant with primary frequency regulation capability according to the direction and amplitude of the frequency deviation.

[0019] Upon receiving the instruction, the virtual power plant aggregation platform autonomously adjusts its total output power to help suppress frequency fluctuations based on the preset frequency power droop characteristics, and autonomously calculates and quickly issues power adjustment instructions to each battery swapping station; the power converters of each battery swapping station change their charging and discharging power according to the instructions to respond to frequency changes.

[0020] When the grid frequency deviation returns to the dead zone range, the provincial grid master station automatically issues an active frequency regulation reset command, and the virtual power plant immediately exits the primary frequency regulation mode and resumes normal control.

[0021] If the grid frequency is higher than the positive action threshold, but the adjustable power resources of the virtual power plant are all in the maximum discharge state, the provincial master station will determine that it has no upward adjustment capability and will not issue an active frequency regulation start command; if the grid frequency is lower than the negative action threshold, but the adjustable power resources of the virtual power plant are all in the maximum charging state, the provincial master station will determine that it has no downward adjustment capability and will not issue an active frequency regulation start command.

[0022] The virtual power plant aggregation platform calculates the total power adjustment based on the droop characteristic and distributes power commands among the various battery swapping stations according to a proportional or adjustable capacity weighting strategy, and calculates power regulation based on the droop characteristic formula.

[0023] Furthermore, when the virtual power plant's control mode is the combined frequency regulation mode:

[0024] When the grid regulation reserve capacity is sufficient, the provincial grid master station prioritizes allocating AGC regulation demand to conventional generating units. Based on regional control deviation and regional demand, the closed-loop regulation algorithm based on regional control deviation calculates grid frequency deviation, tie line power deviation, and load forecast deviation in real time, outputs total power regulation demand, and sends total power regulation instructions to virtual power plants.

[0025] When the power grid is in a frequency emergency control state, the provincial power grid master station first allocates the regulation commands that each conventional unit can undertake based on the upper limit of its single regulation capacity; if the total regulation capacity of the conventional units is insufficient to meet all regulation needs, the remaining demand is allocated to the virtual power plant by issuing a total power command value.

[0026] After receiving the total power command value, the virtual power plant aggregation platform considers factors such as the SOC status, power limit, and response speed of each battery swapping station, and uses an optimization allocation algorithm to decompose the total power command value into the power setting value of each battery swapping station. The optimization allocation algorithm aims to maximize the overall response speed or minimize battery loss, and decomposes the total power command value by solving the objective function.

[0027] During the process of virtual power plants participating in joint frequency regulation and the grid frequency gradually recovering, the provincial power grid master station prioritizes eliminating the control deviation caused by the virtual power plants participating in frequency regulation, and superimposes the deviation value with the actual grid regulation demand as the control target for conventional units for power regulation;

[0028] After the virtual power plant participates in joint frequency regulation and the grid reserve capacity is restored, the provincial grid master station prioritizes restoring the control deviation of the virtual power plant and adds this deviation to the current actual grid regulation demand, which together serve as the control target for conventional units.

[0029] Furthermore, the objective function is:

[0030] ;

[0031] in, This is the power command for the i-th battery swapping station. This represents the base power of the i-th battery swapping station. , , These are the weighting coefficients. This is the optimal operating point for the battery. Costs related to battery degradation;

[0032] The constraints of the objective function include adjustable capability constraints, SOC constraints, power balance constraints, and ramp rate constraints.

[0033] Furthermore, when a provincial power grid master station contains several virtual power plants of different types and capacities, different coordination and allocation strategies are adopted for coordination and allocation based on the power grid status, including:

[0034] The incremental rate strategy aims to minimize the overall system regulation cost by calculating and allocating the optimal output point for each virtual power plant.

[0035] The proportional allocation strategy allocates the total regulating power command proportionally based on the available and adjustable capacity currently reported by each virtual power plant.

[0036] Bidding strategy: Virtual power plants submit frequency regulation capacity and bids in advance, and the main station allocates them in order of price from low to high to meet frequency regulation needs;

[0037] Priority allocation strategy: Priorities are set based on virtual power plant type and performance indicators, and higher priority resources are allocated first;

[0038] The provincial power grid master station executes the selected coordination and allocation strategy, calculates the specific power command value allocated to each virtual power plant, and sends it out through the standard communication interface. The master station continuously monitors the command execution status of each virtual power plant. If a virtual power plant responds abnormally or has insufficient capacity, the strategy recalculation is automatically triggered, and the unfinished power command is redistributed to other available resources.

[0039] Furthermore, the local control system of each battery swapping station receives power command values ​​from the virtual power plant, compares them with the station's current actual output, generates control signals, and drives its power converter to perform charging or discharging operations.

[0040] The present invention discloses a frequency regulation control system for a virtual power plant in a battery swapping station, comprising a virtual power plant and a provincial power grid master station;

[0041] A virtual power plant is formed by aggregating several battery swapping stations;

[0042] The virtual power plant reports AGC controllable signals, active frequency modulation participation signals, and joint frequency modulation participation signals to the provincial power grid master station;

[0043] The provincial power grid master station outputs power grid frequency regulation control commands to the virtual power plants based on the signals reported by the virtual power plants. The power grid frequency regulation control commands include control mode commands, and the control modes include local mode, active frequency regulation mode and joint frequency regulation mode.

[0044] When the virtual power plant's control mode is active frequency regulation mode, the virtual power plant participates in the primary frequency regulation of the power grid; when the virtual power plant's control mode is joint frequency regulation mode, the virtual power plant participates in the secondary frequency regulation of the power grid; when the virtual power plant's control mode is local mode, the provincial power grid master station does not issue power grid frequency regulation control commands to the virtual power plant.

[0045] The AGC controllable signal is used to inform the provincial power grid master station virtual power plant whether it has the ability to receive and execute AGC commands; the active frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the primary frequency regulation of the power grid; the joint frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the secondary frequency regulation of the power grid.

[0046] The computer-readable storage medium of the present invention stores a computer program, which, when executed by a processor, implements the control method for the virtual power plant of the battery swapping station to participate in frequency regulation.

[0047] The computer program product of the present invention includes a computer program that, when executed by a processor, implements a frequency regulation method based on the virtual power plant of the battery swapping station.

[0048] Beneficial effects: Compared with the prior art, the advantages of the present invention are: (1) it aggregates the scattered battery swapping stations into virtual power plants, forming large-scale frequency regulation resources and improving the grid's adaptability to new energy fluctuations; (2) through multi-mode coordinated control, it can support the primary / secondary frequency regulation of the grid and ensure the operation and economic needs of the battery swapping stations; (3) it establishes a standardized communication and optimized allocation model to achieve a balance between rapid power response and extended battery life; (4) it enhances the grid's frequency regulation flexibility, reliability and economy, and provides effective frequency support for high-proportion renewable energy grids. Attached Figure Description

[0049] Figure 1 This is a schematic diagram of the method flow according to an embodiment of the present invention;

[0050] Figure 2 This is a flowchart of the active frequency modulation mode control according to an embodiment of the present invention;

[0051] Figure 3 This is a flowchart of the joint frequency modulation mode control according to an embodiment of the present invention;

[0052] Figure 4 This is a flowchart illustrating the local control execution process of a battery swapping station according to an embodiment of the present invention. Detailed Implementation

[0053] The technical solution of the present invention will be further described below with reference to the accompanying drawings.

[0054] like Figure 1 As shown, the frequency regulation method for the virtual power plant of the battery swapping station to participate in frequency regulation includes the following steps.

[0055] Step 1: Aggregate multiple geographically dispersed battery swapping stations through a communication network, effectively creating a virtual power plant that participates in grid frequency regulation, and establish a mathematical model that can calculate adjustable power.

[0056] The equivalent aggregation of battery swapping stations includes the following steps:

[0057] (1.1) Perform state of charge (SOC) modeling and available capacity modeling for the battery clusters of multiple battery swapping stations respectively, and calculate the dispatchable power range of the i-th battery swapping station at time t as follows:

[0058]

[0059] in and These factors are determined by the upper and lower limits of battery SOC, charging and discharging efficiency, and battery swapping requirements.

[0060] (1.2) Multiple battery swapping stations are aggregated into a virtual power plant (VPP). Using the equivalent virtual machine group modeling method, the total adjustable power of the VPP is reported to the provincial power grid master station. Its total adjustable capacity is:

[0061]

[0062] Where N represents the number of battery swapping stations.

[0063] Step 2 involves adding the virtual power plant of the battery swapping station to the provincial power grid master station AGC control system (hereinafter referred to as the provincial power grid master station), and constructing a frequency regulation control model for the collaborative operation of the virtual power plant of the battery swapping station and the provincial power grid master station AGC. The virtual power plant aggregation platform of the battery swapping station establishes a standardized communication connection with the provincial power grid master station AGC system to achieve bidirectional real-time data interaction.

[0064] The data transmitted by the power grid frequency regulation control model includes two types of data: remote signaling and telemetry data, which are input in real time from the battery swapping station resources to the provincial power grid master station.

[0065] Furthermore, the power grid frequency regulation control model includes static model data and dynamic model data. Static model data includes at least: a unique virtual power plant code, name, dispatch relationship, rated power capacity, maximum adjustable power upper / lower limit, maximum ramp rate, and response time constant. Dynamic model data consists of two types of data input in real-time to the provincial power grid master station by the dynamic demand resource aggregator: remote signaling and telemetry data. The dynamic model data includes at least: real-time total active power, real-time increase / decrease power upper limit, average battery state of charge (SOC), response status, and current control mode.

[0066] The virtual power plant aggregation platform of the battery swapping station and the AGC system of the provincial power grid master station are connected by a redundantly configured dispatch data network using the IEC 61850 standard communication protocol. The aggregation platform periodically uploads dynamic model data to the provincial master station.

[0067] Based on static model data and received dynamic model data, the provincial master station generates an assessment of the virtual power plant's adjustability and a control strategy within the AGC control logic, and issues frequency regulation control commands to the power grid accordingly. The data sent from the provincial power grid master station to the virtual power plant aggregation platform includes: control mode commands, AGC power command values, planned curves, parameter setpoints, and control parameters.

[0068] The provincial power grid master station issues three control modes to the virtual power plant: local mode, active frequency regulation mode, and joint frequency regulation mode.

[0069] Furthermore, the method for determining the control mode by the provincial power grid master station is as follows:

[0070] The virtual power plant sends AGC controllable signals, active frequency regulation participation signals, and joint frequency regulation participation signals to the provincial power grid master station. The AGC controllable signal is used to inform the provincial power grid master station whether the virtual power plant has the ability to receive and execute AGC commands. When the remote signaling value of the AGC controllable signal is "on", it means that it is willing to receive AGC commands, and when the remote signaling value is "off", it is not willing. The active frequency regulation participation signal is used to inform the provincial power grid master station whether the virtual power plant is willing and has the ability to participate in the primary frequency regulation of the power grid. When the remote signaling value of the active frequency regulation participation signal is "on", it means that it is willing and has the ability to participate in the primary frequency regulation of the power grid, and "off" means that it is not willing or does not have the ability. The joint frequency regulation participation signal is used to inform the provincial power grid master station whether the virtual power plant is willing and has the ability to participate in the secondary frequency regulation of the power grid. When the remote signaling value of the joint frequency regulation participation signal is "on", it means that it is willing and has the ability to participate in the secondary frequency regulation of the power grid, and "off" means that it is not willing or does not have the ability.

[0071] (a) When the telemetry values ​​of the AGC controllable signal and the active frequency regulation participation signal sent by the virtual power plant to the provincial power grid master station are both "on", and the telemetry data meets the following conditions, the provincial power grid master station may set the virtual power plant to "active frequency regulation mode" according to the power grid control requirements: ① The deviation between the real-time frequency telemetry value of the power grid and the rated frequency is ≥ ±0.05Hz; ② The telemetry value of the virtual power plant's real-time increase / decrease power limit is ≥ the regulation capacity required for primary frequency regulation; ③ The telemetry value of the average battery state of charge (SOC) is within the safe range (20%-80%); if the telemetry data does not meet the above conditions, the provincial power grid master station will set the virtual power plant to "local mode".

[0072] (b) When the telemetry values ​​of the AGC controllable signal and the joint frequency regulation participation signal sent by the virtual power plant to the provincial power grid master station are both "on", and the telemetry data meets the following conditions, the provincial power grid master station may set the virtual power plant to "joint frequency regulation mode" according to the power grid control requirements: ① the telemetry value of the regional control deviation (ACE) is not equal to 0; ② the telemetry value of the real-time total active power of the virtual power plant deviates from the planned value of the master station by ≤5%; ③ the telemetry value of the actual value of the ramp rate of the battery swapping station meets the command execution requirements; if the telemetry data does not meet the above conditions, the provincial power grid master station will set the virtual power plant to "local mode".

[0073] (c) When the remote signaling value of the AGC controllable signal sent by the virtual power plant to the provincial power grid master station is "on", and the remote signaling values ​​of the active frequency modulation participation signal and the joint frequency modulation participation signal are both "off", the provincial power grid master station determines that the remote signaling value sent by the virtual power plant is abnormal, and without relying on telemetry data for additional determination, directly sets the virtual power plant to "local mode".

[0074] (d) When the telemetry values ​​of the AGC controllable signal, active frequency modulation participation signal, and joint frequency modulation participation signal sent by the virtual power plant are all "on", the provincial power grid master station determines, in conjunction with the telemetry data: if the telemetry conditions of the active frequency modulation mode are met, it can be set to "active frequency modulation mode"; if the telemetry conditions of the joint frequency modulation mode are met, it can be set to "joint frequency modulation mode"; if none of them are met or the need to prioritize the battery swapping demand is required, it is set to "local mode".

[0075] Furthermore, when the provincial power grid master station sets the control mode of the virtual power plant at the battery swapping station to "active frequency regulation mode," if the provincial master station detects that the grid frequency deviation exceeds the set deviation threshold, it will send a start signal to the virtual power plant according to the frequency control requirements, triggering it to participate in primary frequency regulation. Figure 2 As shown, it specifically includes the following:

[0076] (2.1) The provincial power grid master station continuously monitors the real-time frequency of the system. When the frequency deviation exceeds a preset threshold (e.g., ±0.05Hz) and continues for more than a preset delay (e.g., 2-10 seconds), the master station will send an "active frequency regulation start" signal and the frequency deviation value to the virtual power plant aggregation platform with primary frequency regulation capability, based on the direction and amplitude of the frequency deviation. Upon receiving this instruction, the virtual power plant will autonomously adjust its total output power according to the preset frequency-power droop characteristics to help suppress frequency fluctuations and autonomously calculate and quickly issue power adjustment instructions to each battery swapping station. The power converters of each battery swapping station change their charging / discharging power according to the instructions to respond to frequency changes.

[0077] (2.2) When the grid frequency deviation recovers to the dead zone range, the provincial grid master station automatically issues an "active frequency regulation recovery" command, and the virtual power plant then exits the primary frequency regulation mode and resumes normal control.

[0078] (2.3) If the grid frequency is higher than the positive action threshold, but the adjustable power resources of the virtual power plant are all in the maximum discharge state, the provincial master station will determine that it has no upward adjustment capability and will not issue an "active frequency regulation start" command to it in order to avoid ineffective control.

[0079] (2.4) If the grid frequency is lower than the negative action threshold, but the adjustable power resources of the virtual power plant are all in the maximum charging state, the provincial master station will determine that it has no down-adjustment capability and will not issue an "active frequency adjustment start" command.

[0080] (2.5) The virtual power plant aggregation platform will allocate power commands among the various battery swapping stations according to a proportional or adjustable capacity weighting strategy, based on the total power adjustment calculated according to the droop characteristic. The power adjustment amount is calculated according to the droop characteristic formula, which is:

[0081]

[0082] in, The droop factor is (MW / Hz). This is the actual power grid frequency. This is the rated frequency of the power grid.

[0083] Furthermore, when the control mode of the virtual power plant at the battery swapping station is set to "joint frequency regulation mode," the provincial AGC master station treats the virtual power plant at the battery swapping station the same as traditional generator sets, incorporating it into the AGC control closed loop and employing a coordinated control strategy to simultaneously control both the virtual power plant at the battery swapping station and the conventional generator sets. After receiving the instruction, the virtual power plant aggregation platform, within its adjustable capacity, optimizes and decomposes the total power instruction value and distributes it to each subordinate battery swapping station for execution, participating in the secondary frequency regulation of the power grid, such as... Figure 3 As shown, it specifically includes the following:

[0084] (2.6) When the grid regulation reserve capacity is sufficient, the provincial grid master station shall prioritize allocating AGC regulation demand to conventional generating units. The master station shall calculate and send the total power regulation command to the virtual power plant aggregation platform based on the regional control deviation and regional demand using the standard AGC algorithm.

[0085] (2.7) When the power grid is in a frequency emergency control state, that is, when the power grid frequency deviation exceeds the set abnormal action threshold (e.g. When the power grid master station first allocates the regulation commands that each conventional unit can undertake based on the upper limit of its single regulation capacity, if the total regulation capacity of the conventional units is insufficient to meet all regulation needs, the remaining needs are allocated to the virtual power plant. The provincial power grid master station then uses the sum of the allocation results and the current actual output of the virtual power plant as the power control target value for the virtual power plant and issues it out.

[0086] (2.8) After receiving the total power command value, the aggregation platform takes into account the SOC status, power limit, response speed and other factors of each battery swapping station, and adopts an optimized allocation algorithm to decompose the total command into the power setting value of each battery swapping station. Each battery swapping station receives and executes the command, and feeds back its actual output, available capacity and status information to the aggregation platform in real time. The aggregation platform summarizes and uploads the information to the provincial master station to complete the closed-loop control.

[0087] (2.9) During the process of virtual power plants participating in joint frequency regulation and the grid frequency gradually recovering, the provincial power grid master station shall prioritize eliminating the control deviation caused by the virtual power plants participating in frequency regulation, and superimpose the deviation value with the actual regulation demand of the grid as the control target of conventional units for power regulation;

[0088] (2.10) After the virtual power plant participates in joint frequency regulation and the grid reserve capacity is restored, the provincial grid master station shall give priority to restoring the control deviation of the virtual power plant and add the deviation to the current actual grid regulation demand, and use them together as the control target of the conventional unit.

[0089] (2.11) The strategy for optimizing the total power command value of the virtual power plant aggregation platform is as follows: Based on the real-time adjustable power capability, SOC status, and battery health of each battery swapping station, an optimization model is established with the goal of maximizing the overall response speed or minimizing battery loss:

[0090] ;

[0091] Adjustable capability constraints: ;

[0092] SOC constraints: ;

[0093] Power balance constraints: ;

[0094] Climbing speed constraint: .

[0095] in, This is the power command for the i-th battery swapping station. For its basic power, , , These are the weighting coefficients. This is the optimal operating point for the battery. Costs associated with battery degradation.

[0096] Furthermore, when the provincial power grid master station sets the control mode to "local mode," it does not issue power commands to the station. The virtual power plant at the battery swapping station exits the grid frequency regulation service and controls power entirely based on its own operational needs, such as swapping batteries for user vehicles and engaging in off-peak charging / peak discharging arbitrage. The virtual power plant aggregation platform autonomously generates power control plans based on the battery status of each battery swapping station, battery swapping demand forecasts, and grid time-of-use pricing signals. Prioritizing user battery swapping needs, it charges during off-peak hours and discharges during peak hours to achieve arbitrage operation.

[0097] By switching between the three control modes mentioned above, the virtual power plant at the battery swapping station operates in "cooperative frequency regulation mode" when the power grid is running normally, receiving and tracking AGC commands; when a frequency change is detected, it automatically switches to "autonomous frequency regulation mode" to achieve primary frequency regulation assistance; and during peak battery swapping periods, it switches to "local mode" to prioritize meeting users' battery swapping needs. This multi-mode coordination mechanism enhances the power grid's frequency regulation capability while ensuring the battery swapping station's own operational needs, achieving a dual optimization of technical and commercial objectives.

[0098] Step 3: When there are multiple virtual power plants of different types and capacities at the provincial power grid master station, the corresponding control strategies are adopted for coordination and power allocation based on the actual state of the power grid.

[0099] The provincial power grid master station's AGC system assesses the power grid's frequency regulation needs in real time. These needs include regulation direction, regulation capacity, urgency level, and duration. The master station maintains a resource database containing all registered virtual power plants. Each virtual power plant in the database has the following characteristic attributes: power plant type, real-time adjustable capacity, reliability, duration, response speed, and regulation cost. Based on the current power grid status, the master station selects one or a combination of preset coordination and allocation strategies.

[0100] (a) Incremental rate strategy: To achieve the goal of minimizing the overall system regulation cost, calculate and allocate the optimal output point of each virtual power plant;

[0101] (b) Proportional allocation strategy: Based on the available and adjustable capacity currently reported by each virtual power plant, the total regulating power command is allocated proportionally;

[0102] (d) Bidding strategy: Virtual power plants submit frequency regulation capacity and bids in advance, and the main station allocates them in order of price from low to high to meet frequency regulation needs;

[0103] (e) Priority allocation strategy: Priority is set according to the virtual power plant type and performance indicators, and high-priority resources are called first;

[0104] The master station executes the selected strategy, calculates the specific power command value to be allocated to each virtual power plant, and sends it out through the standard communication interface. The master station continuously monitors the command execution status of each virtual power plant. If a virtual power plant responds abnormally or has insufficient capacity, the strategy is automatically recalculated, and the unfinished power commands are reassigned to other available resources.

[0105] Step 4: Each battery swapping station receives and executes power commands: The local control system of each battery swapping station receives power command values ​​from the virtual power plant aggregation platform. This is compared with the station's current actual output to generate control signals, driving its power converter (PCS) to perform charging or discharging operations, thus accurately tracking the command target and feeding the execution results back to the aggregation platform. For example... Figure 4 As shown, the specific steps are as follows:

[0106] (4.1) The local controller of the battery swapping station receives power commands from the aggregation platform. ;

[0107] (4.2) The local controller will issue instructions Adjustable range in real time with this site Perform a verification; if the instruction exceeds the limit, execute according to the boundary value and immediately report an alarm message.

[0108] (4.3) If the instruction is valid, the local controller generates a PWM drive signal through PID control to control the on and off of the power converter (PCS), and adjusts the charging and discharging power of the battery pack, so that the actual output of the station can be quickly and accurately tracked. ;

[0109] (4.4) While executing the instructions, the battery swapping station will feed back key execution status data, including actual output, current average SOC, available capacity and fault status, to the virtual power plant aggregation platform in real time to form a closed-loop control.

[0110] In one embodiment of the present invention, the virtual power plant aggregation platform of the battery swapping station and the system upon which its interaction with the provincial power grid AGC master station depends are both implemented using computer equipment. This equipment system consists of three levels of computing devices: the provincial power grid AGC master station, the virtual power plant aggregation platform, and the local control unit of the battery swapping station. These are interconnected through a high-performance network to jointly perform data acquisition, communication transmission, decision calculation, and power control tasks. The computer program instructions can be used to implement the functions of each step and module in the flowchart, as well as any combination thereof.

[0111] In terms of hardware, the computer equipment includes at least a processor, memory, communication interface, and input / output devices. In terms of software, the computer equipment runs on a Linux or Windows Server operating system to support background multitasking and high-concurrency communication. The system needs to deploy middleware supporting power communication protocols such as IEC 61850 to achieve standardized data interaction between the virtual power plant aggregation platform and the power grid AGC master station. The data visualization and interface modules configured on the equipment provide dispatchers with a real-time monitoring and control interface. In terms of communication, the computer equipment is equipped with a high-speed, low-latency network interface card, supporting fiber optic Ethernet or 5G communication to ensure millisecond-level command transmission. To improve system reliability, a dual-network redundancy structure is preferred, ensuring uninterrupted data interaction even if a single link or device fails. Furthermore, the computer equipment should have encryption authentication and security protection functions to prevent external attacks or data tampering, ensuring the security and reliability of the frequency regulation process.

[0112] Finally, to enhance the system's scalability and fault tolerance, the computer equipment should be able to flexibly expand its computing and storage resources according to changes in the scale of the virtual power plant access and the amount of data processed. Simultaneously, the equipment should possess log tracking, fault diagnosis, and remote operation and maintenance functions to improve operational reliability and maintainability.

[0113] In one embodiment of the present invention, the computer-readable storage medium of the present invention stores a computer program, which, when executed by a processor, implements the control method for the virtual power plant of the battery swapping station to participate in frequency regulation.

[0114] The computer-readable storage medium may include RAM, ROM, EEPROM, CD-ROM or other optical disc storage devices, magnetic disk storage devices or other magnetic storage devices, flash memory or any other medium that can be used to store program code in the form of instructions or data structures and is accessible by a computer.

[0115] The processor is used to execute a computer program stored in memory to implement the various steps in the methods described in the above embodiments.

[0116] In one embodiment of the present invention, the computer program product of the present invention includes a computer program that, when executed by a processor, implements the frequency regulation method based on the virtual power plant of the battery swapping station.

Claims

1. A method for frequency regulation involving a virtual power plant at a battery swapping station, characterized in that, Includes the following steps: Aggregate several battery swapping stations into a virtual power plant; The virtual power plant reports AGC controllable signals, active frequency modulation participation signals, and joint frequency modulation participation signals to the provincial power grid master station; The provincial power grid master station outputs power grid frequency regulation control commands to the virtual power plants based on the signals reported by the virtual power plants. The power grid frequency regulation control commands include control mode commands, and the control modes include local mode, active frequency regulation mode and joint frequency regulation mode. When the virtual power plant's control mode is active frequency regulation mode, the virtual power plant participates in the primary frequency regulation of the power grid; when the virtual power plant's control mode is joint frequency regulation mode, the virtual power plant participates in the secondary frequency regulation of the power grid; when the virtual power plant's control mode is local mode, the provincial power grid master station does not issue power grid frequency regulation control commands to the virtual power plant. The AGC controllable signal is used to inform the provincial power grid master station virtual power plant whether it has the ability to receive and execute AGC commands; the active frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the primary frequency regulation of the power grid; the joint frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the secondary frequency regulation of the power grid.

2. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 1, characterized in that, When the control mode of the virtual power plant is active frequency regulation mode, if the provincial master station detects that the grid frequency deviation exceeds the set deviation threshold, it sends a start signal to the virtual power plant according to the frequency control requirements, triggering it to participate in primary frequency regulation. When the control mode of the virtual power plant is the joint frequency regulation mode, the provincial AGC master station will treat the virtual power plant of the battery swapping station the same as the traditional generator set, and each battery swapping station in the virtual power plant will participate in the secondary frequency regulation of the power grid.

3. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 1, characterized in that, When the remote signaling values ​​of the AGC controllable signal and the active frequency modulation participation signal sent by the virtual power plant to the provincial power grid master station are both in sync, and the telemetry data meets the first condition, the provincial power grid master station sets the virtual power plant to active frequency modulation mode according to the power grid control requirements; otherwise, it sets it to local mode. The first condition includes: the deviation between the real-time frequency telemetry value of the power grid and the rated frequency is ≥ ±0.05Hz, the real-time power increase / decrease limit telemetry value of the virtual power plant is ≥ the regulation capacity required for primary frequency regulation, and the average battery state of charge telemetry value is within the safe range. When the telemetry values ​​of the AGC controllable signal and the joint frequency regulation participation signal sent by the virtual power plant to the provincial power grid master station are both in sync, and the telemetry data meets the second condition, the provincial power grid master station sets the virtual power plant to joint frequency regulation mode according to the power grid control requirements; otherwise, it sets it to local mode. The second condition includes: the telemetry value of the regional control deviation is not equal to 0, the deviation between the telemetry value of the virtual power plant's real-time total active power and the master station's planned value is ≤5%, and the telemetry value of the actual value of the ramp rate of the battery swapping station meets the command execution requirements. When the remote signaling value of the AGC controllable signal sent by the virtual power plant to the provincial power grid master station is "on", and the remote signaling values ​​of the active frequency modulation participation signal and the joint frequency modulation participation signal are both "off", the provincial power grid master station determines that the remote signaling value sent by the virtual power plant is abnormal, and without relying on telemetry data for additional determination, it directly sets the virtual power plant to local mode. When the telemetry values ​​of the AGC controllable signal, active frequency modulation participation signal, and joint frequency modulation participation signal transmitted by the virtual power plant are all in sync, the provincial power grid master station determines the following based on the telemetry data: if the telemetry conditions for active frequency modulation mode are met, it is set to active frequency modulation mode; if the telemetry conditions for joint frequency modulation mode are met, it can be set to joint frequency modulation mode; if none of them are met or the need to prioritize battery swapping needs is required, it is set to local mode.

4. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 1, characterized in that, When the virtual power plant's control mode is active frequency regulation mode: The provincial power grid master station continuously monitors the real-time frequency of the system; when the frequency deviation exceeds the preset threshold and continues to exceed the preset delay, the provincial power grid master station sends an active frequency regulation start signal and the frequency deviation value to the virtual power plant with primary frequency regulation capability according to the direction and amplitude of the frequency deviation. Upon receiving the instruction, the virtual power plant aggregation platform autonomously adjusts its total output power to help suppress frequency fluctuations based on the preset frequency power droop characteristics, and autonomously calculates and quickly issues power adjustment instructions to each battery swapping station; the power converters of each battery swapping station change their charging and discharging power according to the instructions to respond to frequency changes. When the grid frequency deviation returns to the dead zone range, the provincial grid master station automatically issues an active frequency regulation reset command, and the virtual power plant immediately exits the primary frequency regulation mode and resumes normal control. If the grid frequency is higher than the positive action threshold, but the adjustable power resources of the virtual power plant are all in the maximum discharge state, the provincial master station will determine that it has no upward adjustment capability and will not issue an active frequency regulation start command; if the grid frequency is lower than the negative action threshold, but the adjustable power resources of the virtual power plant are all in the maximum charging state, the provincial master station will determine that it has no downward adjustment capability and will not issue an active frequency regulation start command. The virtual power plant aggregation platform calculates the total power adjustment based on the droop characteristic and distributes power commands among the various battery swapping stations according to a proportional or adjustable capacity weighting strategy, and calculates power regulation based on the droop characteristic formula.

5. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 1, characterized in that, When the virtual power plant's control mode is joint frequency regulation mode: When the grid regulation reserve capacity is sufficient, the provincial grid master station prioritizes allocating AGC regulation demand to conventional generating units. Based on regional control deviation and regional demand, the closed-loop regulation algorithm based on regional control deviation calculates grid frequency deviation, tie line power deviation, and load forecast deviation in real time, outputs total power regulation demand, and sends total power regulation instructions to virtual power plants. When the power grid is in a frequency emergency control state, the provincial power grid master station first allocates the regulation commands that each conventional unit can undertake based on the upper limit of its single regulation capacity; if the total regulation capacity of the conventional units is insufficient to meet all regulation needs, the remaining demand is allocated to the virtual power plant by issuing a total power command value. After receiving the total power command value, the virtual power plant aggregation platform considers factors such as the SOC status, power limit, and response speed of each battery swapping station, and uses an optimization allocation algorithm to decompose the total power command value into the power setting value of each battery swapping station. The optimization allocation algorithm aims to maximize the overall response speed or minimize battery loss, and decomposes the total power command value by solving the objective function. During the process of virtual power plants participating in joint frequency regulation and the grid frequency gradually recovering, the provincial power grid master station prioritizes eliminating the control deviation caused by the virtual power plants participating in frequency regulation, and superimposes the deviation value with the actual grid regulation demand as the control target for conventional units for power regulation; After the virtual power plant participates in joint frequency regulation and the grid reserve capacity is restored, the provincial grid master station prioritizes restoring the control deviation of the virtual power plant and adds this deviation to the current actual grid regulation demand, which together serve as the control target for conventional units.

6. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 5, characterized in that, The objective function is: ； in, This is the power command for the i-th battery swapping station. This represents the base power of the i-th battery swapping station. , , These are the weighting coefficients. This is the optimal operating point for the battery. Costs related to battery degradation; The constraints of the objective function include adjustable capability constraints, SOC constraints, power balance constraints, and ramp rate constraints.

7. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 1, characterized in that, When a provincial power grid master station contains several virtual power plants of different types and capacities, different coordination and allocation strategies are adopted according to the power grid status for coordination and allocation, including: The incremental rate strategy aims to minimize the overall system regulation cost by calculating and allocating the optimal output point for each virtual power plant. The proportional allocation strategy allocates the total regulating power command proportionally based on the available and adjustable capacity currently reported by each virtual power plant. Bidding strategy: Virtual power plants submit frequency regulation capacity and bids in advance, and the main station allocates them in order of price from low to high to meet frequency regulation needs; Priority allocation strategy: Priorities are set based on virtual power plant type and performance indicators, and higher priority resources are allocated first; The provincial power grid master station executes the selected coordination and allocation strategy, calculates the specific power command value allocated to each virtual power plant, and sends it out through the standard communication interface. The master station continuously monitors the command execution status of each virtual power plant. If a virtual power plant responds abnormally or has insufficient capacity, the strategy recalculation is automatically triggered, and the unfinished power command is redistributed to other available resources.

8. The method for frequency regulation involving a virtual power plant at a battery swapping station according to claim 1, characterized in that, Each battery swapping station's local control system receives power command values ​​from the virtual power plant, compares them with the station's current actual output, generates control signals, and drives its power converter to perform charging or discharging operations.

9. A control system for frequency regulation involving a virtual power plant at a battery swapping station, characterized in that, This includes virtual power plants and provincial power grid master stations; A virtual power plant is formed by aggregating several battery swapping stations; The virtual power plant reports AGC controllable signals, active frequency modulation participation signals, and joint frequency modulation participation signals to the provincial power grid master station; The provincial power grid master station outputs power grid frequency regulation control commands to the virtual power plants based on the signals reported by the virtual power plants. The power grid frequency regulation control commands include control mode commands, and the control modes include local mode, active frequency regulation mode and joint frequency regulation mode. When the virtual power plant's control mode is active frequency regulation mode, the virtual power plant participates in the primary frequency regulation of the power grid; when the virtual power plant's control mode is joint frequency regulation mode, the virtual power plant participates in the secondary frequency regulation of the power grid; when the virtual power plant's control mode is local mode, the provincial power grid master station does not issue power grid frequency regulation control commands to the virtual power plant. The AGC controllable signal is used to inform the provincial power grid master station virtual power plant whether it has the ability to receive and execute AGC commands; the active frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the primary frequency regulation of the power grid; the joint frequency modulation participation signal is used to inform the provincial power grid master station virtual power plant whether it is willing and has the ability to participate in the secondary frequency regulation of the power grid.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the frequency regulation method for virtual power plants in battery swapping stations according to any one of claims 1-8.

11. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by the processor, it implements the frequency regulation method for virtual power plants in battery swapping stations according to any one of claims 1-8.

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