Charging pile aggregation frequency modulation device and frequency modulation control method thereof

Abstract

The invention provides a charging pile aggregation frequency modulation device, and belongs to the technical field of power system frequency modulation. The device comprises a data acquisition module, an aggregation control module, a frequency modulation execution module and a communication interaction module. The data acquisition module acquires a power system frequency signal, a charging pile operation state parameter and electric vehicle battery state information in real time; the aggregation control module calculates a frequency modulation demand according to the frequency signal, and generates a power adjustment instruction based on the operation state parameter and the battery state information; the frequency modulation execution module receives the power regulation instruction and controls the charging power of the charging pile; and the communication interaction module realizes information interaction between each module and a power system dispatching center. The invention also provides a frequency modulation control method based on the device. The method comprises the steps of data acquisition, frequency modulation demand calculation, resource screening and distribution, instruction execution, feedback adjustment and the like. The adjustable load participates in power grid frequency modulation, the power grid frequency stability is improved, and the auxiliary service function of the electric vehicle charging infrastructure is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of power system frequency modulation, in particular to a charging pile aggregation frequency modulation device and a control method thereof. BACKGROUND

[0002] With the rapid growth of the number of electric vehicles, the number of charging piles, as the key infrastructure for electric vehicle energy supply, also shows explosive growth. At the same time, the grid-connection of large-scale renewable energy leads to the intensification of power system frequency fluctuations, which puts higher requirements on the frequency modulation capability of the power grid. As a controllable load, charging piles have the characteristics of fast response speed and wide distribution, and are considered as an ideal resource for participating in power grid frequency modulation.

[0003] Currently, electric vehicle charging piles have been involved in the research of power grid frequency modulation. CN104253444B discloses a large-scale charging station power grid frequency control system, which includes a charging station information sending and receiving module, a charging station control module, a control strategy output module, and a charging pile information receiving and sending module. Through the participation of large-scale electric vehicles in frequency fluctuation response, and according to the real-time available charging and discharging power of the charging station, the charging and discharging of electric vehicles in the charging station is orderly arranged.

[0004] CN117748532A discloses a frequency response method involving charging pile aggregation load, which is based on variable parameter control of charging pile aggregation load for fast frequency modulation, real-time acquisition of local power grid frequency deviation for decentralized control, and fast processing of load-side frequency drop faults. At the same time, based on variable target control of charging pile aggregation load for fast frequency modulation, the priority of fast frequency response tuning commands and secondary frequency modulation commands is controlled.

[0005] CN117728475B proposes a control method and system of intelligent charging piles supporting power grid frequency control, which acquires the operating state of charging piles in the control area, the vehicle state of electric vehicles connected to the charging piles, and the power grid frequency of the power grid, generates a low-frequency control strategy or a high-frequency control strategy for the charging piles according to the frequency deviation of the power grid.

[0006] CN117748545B discloses a power grid primary frequency modulation method and system of electric vehicle cluster cooperation, which performs real-time bidirectional communication with the electric vehicle cluster for data acquisition, calculates the primary frequency modulation demand of the power grid based on the real-time collected power grid frequency data, and publishes the primary frequency modulation demand. The system issues a primary frequency modulation instruction to the selected electric vehicle cluster and measures the frequency modulation power of the electric vehicle cluster in real time during the frequency modulation period.

[0007] CN118117612A proposes a frequency modulation method, device and system for electric vehicle cluster cooperation, which obtains frequency modulation demand information in real time, evaluates the aggregation adjustment capacity of the electric vehicle cluster, determines the electric vehicle cluster providing frequency modulation service and the frequency modulation amount distribution ratio, and decomposes the active power adjustment amount of the electric vehicle cluster into control instructions.

[0008] However, the existing charging pile participating in grid frequency modulation still has the following problems: first, the adjustment capacity of a single charging pile is limited, which is difficult to meet the large-scale frequency modulation demand of the power system, and the existing technology lacks an effective charging pile aggregation frequency modulation mechanism; second, the existing technology does not fully consider the conflict between electric vehicle user charging demand and grid frequency modulation demand, and lacks effective strategies to balance user experience and system frequency modulation effect; third, the existing communication architecture has problems such as high delay and insufficient reliability, which cannot meet the time requirements of fast frequency modulation response (usually within 100ms); finally, most charging pile designs mainly focus on charging functions, lack of collaborative control mechanisms for grid frequency modulation, and it is difficult to realize the coordination between multiple charging piles. These problems seriously restrict the effect and large-scale application of charging pile resources participating in grid frequency modulation. SUMMARY

[0009] In order to solve the problems of small single pile adjustment capacity, not considering the conflict between user charging demand and grid frequency modulation, high communication delay and lack of collaborative control mechanism in the existing charging pile participating in grid frequency modulation, realize the technical effects of forming large-scale frequency modulation capacity of aggregated distributed charging pile resources, ensuring charging experience while realizing frequency modulation function, meeting the requirements of grid frequency modulation response speed, and promoting the collaborative interaction between charging pile and grid, the present application provides a charging pile aggregation frequency modulation device.

[0010] The technical scheme of the present application is: a charging pile aggregation frequency modulation device is provided, which comprises a data acquisition module, an aggregation control module, a frequency modulation execution module and a communication interaction module; the data acquisition module is used for real-time acquisition of frequency signal of power system, operating state parameters of each charging pile and connected electric vehicle battery state information; the aggregation control module is in communication connection with the data acquisition module, and is used for calculating frequency modulation demand according to the frequency signal, and generating power adjustment instructions of each charging pile based on the operating state parameters and battery state information; the frequency modulation execution module is in communication connection with the aggregation control module, and is used for receiving the power adjustment instructions and controlling the charging power of each charging pile; the communication interaction module is used for realizing information interaction between the data acquisition module, the aggregation control module, the frequency modulation execution module and the power system dispatching center.

[0011] Preferably, the data acquisition module comprises a frequency sensor, a charging pile state monitoring unit and a battery management system interface, the frequency sensor is used to acquire the real-time frequency of the power grid, the charging pile state monitoring unit is used to acquire the current power, connection state and fault information of the charging pile, and the battery management system interface is used to acquire the state of charge (SOC), temperature and charging demand of the electric vehicle battery.

[0012] Further, the aggregation control module comprises a frequency regulation demand calculation unit, which is used to determine the total frequency regulation power demand P_total according to the power grid frequency deviation Δf (Δf = actual frequency - rated frequency), when Δf > 0, the total charging power needs to be reduced to suppress the frequency overshoot, and when Δf < 0, the total charging power needs to be increased to increase the frequency.

[0013] A resource screening unit is used to screen the charging pile resources that can participate in frequency regulation according to the charging pile operating state and battery state information; and a power distribution unit is used to distribute the total frequency regulation power demand P_total to each screened charging pile according to a preset strategy to generate a power adjustment instruction.

[0014] Preferably, the frequency regulation execution module comprises a power adjustment unit and a feedback monitoring unit, the power adjustment unit is used to realize the rapid adjustment (response time ≤ 100 ms) of the charging power by controlling the rectifier or inverter output of the charging pile, and the feedback monitoring unit is used to acquire the actual power adjustment amount of each charging pile in real time and feed back to the aggregation control module.

[0015] Further, the communication interaction module adopts 5G / edge computing technology to support low-delay (≤ 50 ms) and high-reliability bidirectional communication, and the information interaction comprises uploading the adjustable capacity and actual frequency regulation contribution to the dispatch center, and receiving the frequency regulation instruction and price signal issued by the dispatch center.

[0016] Preferably, the preset strategy further comprises a user incentive mechanism, when the user allows the charging pile to participate in frequency regulation, the incentive is realized through charging fee reduction or integral reward, and the incentive mechanism is positively correlated with the frequency regulation contribution degree.

[0017] The beneficial effects of the present application are as follows:

[0018] 1. By aggregating the adjustable capacity of multiple distributed charging piles, a large-scale frequency regulation resource is formed, effectively solving the problem of small adjustable capacity of a single charging pile, and meeting the power capacity requirement of power grid frequency regulation;

[0019] 2. By considering the battery state of the electric vehicle and the charging demand of the user through the resource screening unit, the user's charging experience is guaranteed, and the conflict between the user's demand and the power grid frequency regulation is solved;

[0020] 3. The use of 5G / edge computing and other low-latency communication technologies and fast power regulation technologies (response time ≤100ms) enables rapid response to power grid frequency fluctuations, meeting the requirements of the power grid for frequency modulation response speed;

[0021] 4. User participation is improved through user incentive mechanisms, promoting the coordinated interaction between charging piles and the power grid, and achieving a win-win situation for the power grid and users.

[0022] Compared with the prior art, the present application not only improves the stability of the power grid frequency, but also brings economic benefits to users while ensuring user experience, and has significant technical and economic value. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 System block diagram of the present application

[0024] Figure 2 Flowchart of the frequency modulation control method of the present application DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme of the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all.

[0026] Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor fall within the scope of the present application.

[0027] Embodiment one

[0028] A charging pile aggregation frequency modulation device includes a data acquisition module, an aggregation control module, a frequency modulation execution module, and a communication interaction module, which are connected through communication to realize information transmission and functional cooperation.

[0029] The data acquisition module acquires real-time frequency signals of the power system, operating state parameters of each charging pile, and connected electric vehicle battery state information. The module includes a frequency sensor, a charging pile state monitoring unit, and a battery management system interface. The frequency sensor acquires real-time frequency of the power grid, providing basic data for frequency modulation decision; the charging pile state monitoring unit obtains the current power, connection state and fault information of the charging pile, ensuring that the charging pile is in a responsive state before the frequency modulation command is issued; the battery management system interface obtains the state of charge (SOC), temperature and charging demand of the electric vehicle, which are used to determine whether the electric vehicle is suitable for participating in frequency modulation response.

[0030] The aggregation control module is in communication connection with the data acquisition module, calculates frequency regulation demand according to the frequency signal, and generates power regulation instructions of each charging pile based on the operating state parameters and the battery state information. The module includes a frequency regulation demand calculation unit, a resource screening unit and a power distribution unit.

[0031] The frequency regulation demand calculation unit determines the total frequency regulation power demand P_total according to the grid frequency deviation Δf (Δf = actual frequency - rated frequency). When Δf is greater than 0, the total charging power needs to be reduced to suppress the excessively high frequency, and when Δf is less than 0, the total charging power needs to be increased to support the frequency recovery.

[0032] The resource screening unit screens the charging piles that meet the frequency regulation response conditions based on the electric vehicle battery SOC and the user charging demand, for example, the charging piles with SOC in the range of 20% to 80% and the user allowing power regulation.

[0033] The power distribution unit distributes the total frequency regulation power demand P_total to the screened charging piles according to a preset strategy, and generates power regulation instructions ΔP_i of each charging pile.

[0034] The preset strategy can be proportional distribution according to the rated power of the charging pile or priority distribution according to the response speed.

[0035] In a preferred embodiment, the preset strategy further includes a user incentive mechanism. When the user allows the charging pile to participate in frequency regulation, the incentive is achieved through charging fee reduction or integral reward, and the incentive mechanism is positively correlated with the frequency regulation contribution.

[0036] Such an incentive mechanism can improve the enthusiasm of users to participate in frequency regulation, expand the adjustable resource pool, and enhance the system frequency regulation capability.

[0037] The frequency regulation execution module is in communication connection with the aggregation control module, receives the power regulation instructions and controls the charging power of each charging pile. The module includes a power regulation unit and a feedback monitoring unit. The power regulation unit adjusts the charging power by controlling the rectifier or inverter output of the charging pile, and the response time is not more than 100 milliseconds, ensuring the timeliness of frequency regulation response.

[0038] The feedback monitoring unit collects the actual power regulation amount of each charging pile in real time and feeds back to the aggregation control module, so that the aggregation control module can adjust the subsequent instructions according to the actual execution situation, forming a closed-loop control.

[0039] The communication interaction module realizes the information interaction between the data acquisition module, the aggregation control module, the frequency regulation execution module and the power system dispatching center. The module adopts 5G / edge computing technology, supports low-delay and high-reliability bidirectional communication, and the delay time is not more than 50 milliseconds.

[0040] Information exchange includes uploading adjustable capacity and actual frequency regulation contribution to the dispatch center, as well as receiving frequency regulation commands and price signals issued by the dispatch center. Efficient communication ensures that the charging pile aggregation frequency regulation system can quickly respond to the grid's frequency regulation needs and maintain information synchronization with the power system dispatch center.

[0041] The workflow of the charging pile aggregation frequency regulation device is as follows: First, the data acquisition module continuously monitors the grid frequency, charging pile status, and electric vehicle battery information; when the grid frequency deviates from the rated value, the aggregation control module calculates the required frequency regulation power and selects charging pile resources that can participate in frequency regulation; then, it allocates frequency regulation tasks and generates power adjustment instructions according to the preset strategy; after receiving the instructions, the frequency regulation execution module quickly adjusts the charging power; at the same time, the communication interaction module maintains information exchange with the power system dispatch center, receives dispatch instructions, and reports the execution status.

[0042] The entire process is automated, enabling rapid response and precise regulation of the power grid frequency.

[0043] Example 2

[0044] A frequency modulation control method based on a charging pile aggregation frequency modulation device, the method being executed using the device described in Embodiment 1, includes the following steps:

[0045] Step S1: The data acquisition module collects the grid frequency, charging pile status and battery information in real time and uploads it to the aggregation control module. In this step, the data acquisition module obtains the real-time frequency data of the grid through the frequency sensor, obtains the current power, connection status and fault information of each charging pile through the charging pile status monitoring unit, and obtains information such as the battery state of charge, temperature and charging demand of the electric vehicle through the battery management system interface.

[0046] This data serves as the basis for subsequent frequency adjustment decisions and is uploaded in real time to the aggregation control module for processing.

[0047] Step S2: The aggregation control module calculates the frequency deviation Δf. If |Δf| exceeds a threshold (e.g., ±0.1Hz), the frequency regulation process is initiated, and the total frequency regulation power demand P_total is calculated. After receiving the grid frequency data, the aggregation control module calculates the frequency deviation Δf (actual frequency minus rated frequency). When the absolute value of the frequency deviation exceeds the preset threshold of 0.1Hz, the system determines that the grid frequency is abnormal and the frequency regulation process needs to be initiated.

[0048] The frequency regulation demand calculation unit calculates the total frequency regulation power P_total required by the power grid based on the magnitude and direction of the frequency deviation. When Δf is positive, it indicates that the power grid frequency is too high and the charging power needs to be reduced; when Δf is negative, it indicates that the power grid frequency is too low and the charging power needs to be increased.

[0049] Step S3: Select charging pile resources that meet the conditions, allocate P_total according to a preset strategy, and generate power adjustment instructions for each charging pile. In this step, the resource selection unit first selects charging piles that meet the frequency regulation response conditions based on the electric vehicle battery SOC and user charging needs, such as charging piles with a battery SOC between 20% and 80% and where the user allows power adjustment. Then, the power allocation unit allocates the total frequency regulation power demand P_total to these charging piles according to a preset strategy. The preset strategy can be based on the proportion of the charging pile's rated power or on the priority of response speed.

[0050] For users participating in frequency regulation, the system will provide corresponding charging fee reductions or points rewards based on their contribution to frequency regulation, incentivizing more users to participate in the frequency regulation service. After allocation, a power adjustment command ΔP_i is generated for each charging station.

[0051] Step S4: The frequency modulation execution module executes the adjustment command, adjusts the charging pile power, and feeds back the actual adjustment amount to the aggregation control module. After receiving the power adjustment command, the frequency modulation execution module controls the rectifier or inverter output of the charging pile through the power adjustment unit to achieve rapid adjustment of the charging power. The entire response process is completed within 100 milliseconds, ensuring timely response to grid frequency fluctuations. Simultaneously, the feedback monitoring unit collects the actual power adjustment amount of each charging pile in real time and feeds this data back to the aggregation control module, forming a closed-loop control.

[0052] Step S5: The aggregation control module corrects the power allocation based on the feedback information until the grid frequency returns to the normal range. After receiving the actual power adjustment feedback, the aggregation control module compares it with the expected adjustment amount and calculates the deviation. If some charging piles fail to fully execute the adjustment command, the aggregation control module will reallocate the remaining frequency regulation demand to other available resources. Simultaneously, the system continuously monitors grid frequency changes. When the frequency returns to the normal range (absolute frequency deviation less than 0.1Hz), the system gradually restores the normal charging power of the charging piles, completing one frequency regulation process.

[0053] In a preferred embodiment, the communication module maintains information exchange with the power system dispatch center throughout the frequency regulation process, uploading adjustable capacity and actual frequency regulation contribution data, and receiving frequency regulation commands and price signals issued by the dispatch center. This two-way communication mechanism ensures that the charging pile aggregated frequency regulation system can operate in coordination with the power grid dispatch system, improving overall frequency regulation efficiency.

[0054] Through the aforementioned frequency regulation control method, the charging pile aggregation frequency regulation device can quickly respond to grid frequency fluctuations, provide flexible frequency regulation services, and effectively support grid frequency stability. This method fully utilizes the adjustability during electric vehicle charging, aggregating dispersed charging pile resources into effective frequency regulation resources. It not only meets the charging needs of electric vehicle users but also provides auxiliary services to the grid, achieving a win-win situation.

[0055] Example 3

[0056] This embodiment provides a power grid frequency regulation method, which can be applied to the frequency control of the power system to ensure that the power grid frequency is stable within the target range.

[0057] The power grid frequency regulation method includes the following steps:

[0058] Step S1: Frequency monitoring. The current frequency value of the power grid is monitored in real time. A high-precision frequency measurement device is used for data acquisition, with a sampling period of 20 milliseconds to ensure the real-time performance and accuracy of the frequency data.

[0059] Step S2: Frequency Deviation Calculation. The monitored current frequency value is compared with the standard frequency value of 50Hz to calculate the frequency deviation. When the frequency deviation exceeds ±0.5Hz, the system determines that the frequency modulation process needs to be initiated.

[0060] Step S3: Frequency Regulation Strategy Formulation. Based on the magnitude and trend of the frequency deviation, a corresponding frequency regulation strategy is formulated. When the frequency is below 49.5Hz, the power generation output is increased; when the frequency is above 50.5Hz, the power generation output is reduced or the load is increased.

[0061] Step S4: Frequency Regulation Command Issuance. The established frequency regulation strategy is converted into specific frequency regulation commands, which are then issued to each frequency regulation power source through the power dispatch automation system. The frequency regulation command includes parameters such as the target frequency value, frequency regulation rate, and frequency regulation duration.

[0062] Step S5: Frequency Modulation Execution. After receiving the frequency modulation command, each frequency modulation power supply adjusts its output according to the command requirements and performs frequency regulation. During the frequency modulation process, the system continuously monitors frequency changes and adjusts the frequency modulation strategy accordingly.

[0063] Step S6: Frequency Stability Determination. During frequency modulation, the system continuously monitors the power grid frequency. When the power grid frequency recovers to the range of 49.9Hz-50.1Hz and operates stably within this range for more than 5 minutes, the system determines that the frequency has stabilized within the target range.

[0064] Step S7: Frequency modulation process ends. When the grid frequency stabilizes within the range of 49.9Hz-50.1Hz, the system ends the frequency modulation process and enters the normal frequency monitoring state, but continues to monitor the grid frequency so that the frequency modulation process can be started in time if the frequency deviates again.

[0065] In a preferred embodiment, frequency monitoring employs a distributed frequency acquisition system, which simultaneously acquires frequency data at multiple key nodes of the power grid and calculates the system frequency value through data fusion technology, thereby improving the accuracy and reliability of frequency monitoring.

[0066] In another preferred embodiment, the frequency modulation strategy is formulated using a fuzzy control algorithm, which automatically calculates the optimal frequency modulation parameters based on the magnitude and rate of change of the frequency deviation, thereby achieving intelligent and precise frequency modulation.

[0067] In practical applications, this method can effectively cope with power grid frequency fluctuations, especially in situations such as large load fluctuations or generator failures. It can quickly adjust the power grid frequency to ensure the safe and stable operation of the power grid. Through the implementation of this method, power grid frequency stability is significantly improved, with a frequency qualification rate exceeding 99.8%, effectively reducing the risk of power grid accidents caused by frequency anomalies.

[0068] Finally, it should be noted that the above descriptions are merely preferred embodiments of this application, and this application is not limited to the above embodiments. It is understood that other improvements and variations directly derived or conceived by those skilled in the art without departing from the spirit and concept of this application should be considered to be included within the protection scope of this application.

Claims

1. A charging pile poly-frequency modulation device, characterized in that, Comprise: a data acquisition module for real-time acquisition of frequency signals of the power system, operating state parameters of each charging pile, and connected electric vehicle battery state information; an aggregated control module in communication connection with the data acquisition module, configured to calculate frequency regulation demand according to the frequency signals, and generate power regulation instructions for each charging pile based on the operating state parameters and battery state information; a frequency regulation execution module in communication connection with the aggregated control module, configured to receive the power regulation instructions and control the charging power of each charging pile; a communication interaction module for realizing information interaction between the data acquisition module, the aggregated control module, the frequency regulation execution module, and the power system dispatching center.

2. The charging pile according to claim 1, wherein, The data acquisition module comprises a frequency sensor, a charging pile state monitoring unit, and a battery management system interface, the frequency sensor is used to acquire real-time frequency of the power grid, the charging pile state monitoring unit is used to obtain the current power, connection state, and fault information of the charging pile, and the battery management system interface is used to obtain the state of charge (SOC), temperature, and charging demand of the electric vehicle battery.

3. The charging pile according to claim 1, wherein, The aggregated control module comprises: a frequency regulation demand calculation unit configured to determine the total frequency regulation power demand P_total according to the power grid frequency deviation Δf (Δf = actual frequency - rated frequency), when Δf>0, the total charging power needs to be reduced to suppress the excessively high frequency, when Δf<0, the total charging power needs to be increased to support the frequency recovery; a resource screening unit configured to screen out charging piles that meet the frequency regulation response conditions (such as SOC being in the range of 20%-80% and the user allowing power regulation) based on the electric vehicle battery SOC and the user charging demand; and a power distribution unit configured to distribute the total frequency regulation power demand P_total to the screened charging piles according to a preset strategy (such as according to the charging pile rated power ratio, response speed priority), and generate power regulation instructions ΔP_i for each charging pile.

4. The charging pile according to claim 1, wherein, The frequency regulation execution module comprises a power regulation unit and a feedback monitoring unit, the power regulation unit is used to realize rapid adjustment (response time ≤100ms) of the charging power by controlling the rectifier or inverter output of the charging pile, and the feedback monitoring unit is used to acquire the actual power regulation amount of each charging pile in real time and feed back to the aggregated control module.

5. The charging pile according to claim 1, wherein, The communication interaction module adopts 5G / edge computing technology, supports low-delay (≤50ms) and high-reliability bidirectional communication, and the information interaction includes uploading adjustable capacity and actual frequency regulation contribution to the dispatching center, and receiving frequency regulation instructions and price signals issued by the dispatching center.

6. The charging pile aggregation frequency modulation device according to claim 3, characterized in that, The preset strategy further comprises a user incentive mechanism, when the user allows the charging pile to participate in frequency regulation, the incentive is realized through charging fee reduction or integral reward, and the incentive mechanism is positively correlated with the frequency regulation contribution degree.

7. The charging pile aggregated frequency regulation device according to claims 1-6, wherein the frequency regulation control method comprises the following steps: Step S1: The data acquisition module collects the grid frequency, charging pile status and battery information in real time and uploads them to the aggregation control module; Step S2: The aggregation control module calculates the frequency deviation Δf. If |Δf| exceeds the threshold value (such as ±0.1 Hz), the frequency regulation process is started, and the total frequency regulation power demand P_total is calculated; Step S3: The charging pile resources that meet the conditions are screened, P_total is allocated according to the preset strategy, and the power adjustment instructions for each charging pile are generated; S4: The frequency regulation execution module executes the adjustment instructions, adjusts the charging pile power, and feeds back the actual adjustment amount to the aggregation control module; S5: The aggregation control module corrects the power allocation according to the feedback information until the grid frequency returns to the normal range (such as 49.9 Hz-50.1 Hz), and the frequency regulation process ends.

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