Ordered charging control system and method for electric vehicle

Abstract

The invention discloses an orderly charging control system and method for an electric vehicle, and relates to the technical field of electric vehicle charging. Comprising a charging pile and a control terminal, the control terminal is electrically connected with the charging pile, the charging pile comprises an electric vehicle SOC acquisition module, a charging power acquisition module, a charging time slot acquisition module and a charging control module, and the electric vehicle SOC acquisition module is used for acquiring an electric vehicle SOC from an electric vehicle battery management system by an electric vehicle carrier every 10 minutes; the charging power acquisition module is used for acquiring the corresponding total available power of the power grid in the frequency fluctuation interval of the power grid from the control terminal every five minutes; the charging time slot acquisition module is used for acquiring a charging time slot according to data acquired by the electric vehicle SOC acquisition module and the charging power acquisition module, and the charging time slot comprises time and charging power; and the charging control module is used for charging the battery of the electric vehicle according to the sequence of the charging time slots.

Description

Technical Field

[0001] The present invention relates to the technical field of orderly charging of electric vehicles, and in particular to an orderly charging control system and method for electric vehicles. Background Art

[0002] The scale and pace of deployment of charging stations within residential communities to power new energy vehicles is rapidly increasing. Simultaneously, smart grids, as critical urban infrastructure, need to connect and coordinate the charging load of a large number of electric vehicles. The increasing proportion of electric vehicle charging load in the grid's overall load can lead to significant fluctuations in grid frequency, negatively impacting voltage and frequency regulation. Currently, most residential communities do not allocate power based on peak electricity demand when deploying charging stations. During peak charging periods, the excessive number of charging stations and the charging load exceeding the community's designed load can cause voltage sags and low power factor, impacting grid quality and causing a drop in grid frequency, which in turn affects residents' electricity needs. On the one hand, as demand for electric vehicle charging increases and electricity resources become scarce, the available resources of residential charging stations are underutilized. On the other hand, unstable and volatile voltage during the charging process can reduce charging efficiency, increase charging times, and lead to unnecessary waste of resources. Given the limited power resources available, a balanced and orderly charging solution is needed to ensure the stable development of new energy electric vehicles, balancing power demand and charging load, and fully utilizing the resources of existing residential charging stations.

[0003] Therefore, in view of this, the inventor has studied and improved the existing technology and its shortcomings, and provided an electric vehicle orderly charging control system and method, in order to achieve a more practical purpose. Summary of the Invention

[0004] In order to solve the problems mentioned in the above background technology, the present invention provides an electric vehicle orderly charging control system and method.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] An orderly charging control system for electric vehicles includes a charging pile and a control terminal. The control terminal is electrically connected to the charging pile. The charging pile includes: an electric vehicle SOC acquisition module, a charging power acquisition module, a charging time slot acquisition module, and a charging control module. The electric vehicle SOC acquisition module is used for the electric vehicle onboard machine to obtain the electric vehicle SOC from the electric vehicle battery management system every 10 minutes; the charging power acquisition module is used for obtaining the corresponding total available power of the power grid within the power grid frequency fluctuation range from the control terminal every 5 minutes; the charging time slot acquisition module is used for obtaining the charging time slot based on the data obtained by the electric vehicle SOC acquisition module and the charging power acquisition module. The charging time slot includes time and charging power, and the charging time slots are arranged in chronological order to form a charging process; the charging control module is used to charge the electric vehicle battery in the order of the charging time slots.

[0007] Preferably, the charging time slot acquisition module is used to obtain the charging time slot corresponding to the parking period of the electric vehicle. During the parking period of the electric vehicle, if the grid frequency exceeds the range of the total available grid power obtained by the charging power acquisition module, the charging power is adjusted according to a preset strategy to obtain a new charging time slot.

[0008] Preferably, the charging time slot acquisition module is used to take time 0 as the starting time and 24 hours as the cycle, and divide the entire cycle into six time periods of 0-4, 4-8, 8-12, 12-16, 16-20 and 20-24 every 4 hours, and set the SOC interval [Si-1, Si] according to the time period, i is the time period identifier, i=1, 2, 3, 4, 5, 6, and obtain the initial charging time slot according to the SOC interval corresponding to the 6 time periods.

[0009] Preferably, the orderly charging system further includes a grid frequency monitoring module, which is used to monitor the grid frequency fluctuation range and provide the charging power acquisition module with the total available grid power according to the grid frequency fluctuation range.

[0010] Preferably, the charging time slot acquisition module is used to determine that when the available total power interval of the charging station where the electric vehicle is parked exceeds the available total power interval corresponding to the current charging time slot, the charging state of the current charging time slot is the standby state; when the electric vehicle parking period corresponds to multiple available total power intervals, the initial charging time slot is determined according to the SOC size of the electric vehicle.

[0011] Preferably, when the total available charging power of the charging station is greater than the total charging power of the electric vehicle battery + the power requirement corresponding to the remaining charging time of the charging pile currently being charged, the remaining charging power is halved to obtain the available power required for the remaining charging time of the charging pile currently being charged. If the current charging power is not satisfied, the charging pile currently being charged is controlled to charge at half of the current power; or if the current charging power is not satisfied, the charging of the current charging pile is controlled to end.

[0012] Preferably, the control terminal is used to monitor the real-time power of the charging station load. When the real-time power of the charging station load exceeds its corresponding preset threshold, power limitation is performed. The power limitation includes: controlling the charging piles currently charging in the charging station to charge at half of the current power; or controlling the charging piles in the charging station whose remaining charging time does not exceed the preset charging time to end charging; or controlling the charging piles currently charging to end charging, and controlling cars that have been parked for more than the preset parking time T not to charge.

[0013] On the other hand, the present invention also provides an orderly charging control method for electric vehicles, comprising the following steps: the system obtains the SOC of the electric vehicle; obtains the total available power of the power grid corresponding to the power grid frequency fluctuation range from the control terminal every 5 minutes; obtains the charging time slot according to the SOC of the electric vehicle and the total available power of the power grid, wherein the charging time slot includes time and charging power; and charges the electric vehicle battery based on the order of the charging time slots.

[0014] Preferably, the electric vehicle battery is charged based on the sequence of charging time slots, and the specific charging time is sent to each charging pile through the control terminal, and the target voltage of each target stage of charging under the preset total charging time is calculated. The charging time of each stage is the ratio of the charging target voltage to the initial charging voltage multiplied by the percentage of the total charging time.

[0015] Preferably, the preset total charging time is divided into 4 stages; in the first stage, the charging time is 5%-10%, the current gradually increases from 0A to 100A, and the voltage increases slowly with the increase of current. The target battery voltage every 100 milliseconds in the first stage is calculated according to the voltage increase rate. According to the difference between the actual battery voltage and the target voltage in the previous period, the corrected charging current of the period is calculated, and the corrected charging current = (target voltage - actual voltage) × battery cell capacitance × 0.5A. In the second stage, 10%-30%, the current is in constant current mode, 100A, and the voltage rises slowly with the increase of current. The target battery voltage of the period is calculated according to the voltage increase rate. , according to the difference between the actual battery voltage and the target voltage in the previous period, the corrected charging current for this period is calculated. In the third stage, 30%-60%, the charging current drops from 100A to 50A, and the voltage drops slowly as the current decreases. The target battery voltage for the period is calculated based on the voltage reduction rate. In the 30% stage, the current reduction rate is linear. According to the difference between the actual battery voltage and the target voltage in the previous period, the corrected charging current for this period is calculated. In the fourth stage, greater than 60%, the charging current is in constant voltage mode and maintained at a constant voltage of 40V. According to the difference between the actual battery voltage and the target voltage in the previous period, the corrected charging current for this period is calculated.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The present invention obtains charging time slots according to the SOC of electric vehicles and the total available power of the power grid, and charges the electric vehicle batteries based on the order of the charging time slots. This can fully utilize all time slots of the community charging piles to complete the charging of as many electric vehicles as possible, reduce the charging interference between the various time slots in the charging station, and at the same time minimize the impact on the power grid frequency, have little impact on the power grid, relieve the pressure on the power grid, further ensure the safety of the power grid, and make the adjustment and distribution of the total power in the charging station more reasonable.

[0018] 2. This invention optimizes the charging process by dividing the preset total charging time into sections and controlling the charging current and voltage at each stage, ensuring battery charging safety and efficiency. By applying different charging modes and correction strategies at different stages, charging time is reduced, charging speed is increased, and battery damage is avoided. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0020] Figure 1This is a structural block diagram of an orderly charging control system for electric vehicles according to the present invention. DETAILED DESCRIPTION

[0021] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention. Example 1

[0022] See also Figure 1 An embodiment of the present invention provides an orderly charging control system for electric vehicles, comprising a charging pile and a control terminal, wherein the control terminal is electrically connected to the charging pile. The charging pile comprises: an electric vehicle state of charge (SOC) acquisition module, a charging power acquisition module, a charging time slot acquisition module, and a charging control module. The electric vehicle SOC acquisition module is configured to have the electric vehicle onboard computer acquire the electric vehicle state of charge (SOC) from the electric vehicle battery management system every 10 minutes. The charging power acquisition module is configured to acquire the total available power of the power grid corresponding to the power grid frequency fluctuation interval from the control terminal every 5 minutes, so that the system understands the current power supply capacity of the power grid and can reasonably arrange the charging power. The charging time slot acquisition module is configured to obtain the charging time slot based on the data acquired by the electric vehicle SOC acquisition module and the charging power acquisition module. The charging time slot includes time and charging power, and the charging time slots are arranged in chronological order to form a charging process, ensuring that the charging process proceeds in an orderly manner. The charging control module is configured to charge the electric vehicle battery in the order of the charging time slots. The charging control module intelligently controls the charging process based on the information provided by the charging time slot acquisition module to achieve orderly charging of the electric vehicle. To further achieve this goal, an embodiment of the present invention provides an orderly charging control system for electric vehicles. The charging time slot acquisition module is used to obtain the charging time slot corresponding to the electric vehicle's parking period. During the electric vehicle's parking period, if the grid frequency exceeds the range of the total available grid power obtained by the charging power acquisition module, the charging power is adjusted according to a preset strategy to obtain a new charging time slot, which is sent to the charging control module. The new charging time slot will reflect the adjusted charging power and possible changes in charging time. The preset strategy may be to reduce the charging power to adapt to the power supply capacity of the community grid, or to increase the charging power when the grid power supply capacity is restored. At the same time, during the electric vehicle's parking period, the charging time slot acquisition module will determine the initial charging time slot for each electric vehicle based on the electric vehicle's SOC requirement and the total available grid power. This includes the start and end times of charging, as well as the charging power within each time slot.

[0023] Furthermore, the charging time slot acquisition module dynamically adjusts the charging time slot based on the current SOC (State of Charge) of the electric vehicle, the charging power requirement, the available power of the power grid, the number of charging piles at the charging station, and the charging needs of the user. The specific steps for dynamically adjusting the charging time slot are as follows:

[0024] 1. Initialize charging time slot: Assign an initial charging time slot to each EV based on its SOC and charging demand.

[0025] 2. Calculate the total required power: ,

[0026] 3. Adjust the charging time slot: If P total_demand ≤P grid , then all electric vehicles can be charged according to the preset charging time. total_demand >P grid , then the charging time slot needs to be adjusted to adapt to the power supply capacity of the grid.

[0027] 4. Dynamic adjustment: For each electric vehicle, calculate the adjustment factor K of its charging time slot i : × , the adjusted charging time slot T i ′ is: T i ′=K i ×T i .

[0028] 5. Corrected charging current: For each charging stage, the corrected charging current is calculated based on the difference between the actual voltage and the target voltage: I correction,i =(target voltage - actual voltage) × battery cell capacitance × 0.5A.

[0029] 6. Update charging strategy: Repeat steps 2-5 to dynamically adjust the charging time slot and charging current based on the real-time power supply capacity of the power grid and the SOC changes of the electric vehicle.

[0030] 7. Output adjusted charging time slot T i ′ and the corrected charging current I correction,i .

[0031] The input parameters that need to be explained are as follows: SOC i : The current SOC of the i-th electric vehicle; P req,i : Charging power requirement of the i-th electric vehicle; P grid : the total available power of the grid; n: the number of charging piles in the charging station; Ttotal : total charging time; T i : The preset charging time of the i-th electric vehicle.

[0032] To further achieve this goal, an embodiment of the present invention provides an orderly charging control system for electric vehicles. The charging time slot acquisition module is used to use time 0 as the starting time and a 24-hour cycle to divide the entire cycle into six time periods of 0-4, 4-8, 8-12, 12-16, 16-20, and 20-24, with SOC intervals [Si-1, Si] set for each time period, where i is the time period identifier. The initial charging time slot is obtained for each of the six time periods. To further achieve this goal, an embodiment of the present invention provides an orderly charging control system for electric vehicles. The orderly charging system also includes a power grid frequency monitoring module, which is used to monitor the power grid frequency fluctuation interval and provide the charging power acquisition module with the total available power of the power grid based on the power grid frequency fluctuation interval. To further achieve this goal, an embodiment of the present invention provides an orderly charging control system for electric vehicles. The charging time slot acquisition module is used to set the charging state of the current charging time slot to standby when the available total power interval of the charging station where the electric vehicle is parked exceeds the available total power interval corresponding to the current charging time slot. When the electric vehicle parking period corresponds to multiple available total power intervals, the initial charging time slot is determined according to the electric vehicle's SOC size. To further achieve this goal, an embodiment of the present invention provides an orderly charging control system for electric vehicles. When the available total charging power of the charging station is greater than the total charging power of the electric vehicle battery + the power requirement corresponding to the remaining charging time of the currently charging charging pile, the remaining charging power is halved to obtain the available power required for the remaining charging time of the currently charging charging pile. If the current charging power is not satisfied, the currently charging charging pile is controlled to charge at half of the current power; if the current charging power is not satisfied, the current charging pile is controlled to terminate charging. To further achieve this goal, an embodiment of the present invention provides an orderly charging control system for electric vehicles. The system also includes a control terminal, which is used to monitor the real-time power of the charging station load. When the real-time power of the charging station load exceeds its corresponding preset threshold, power limitation is performed. The power limitation includes: controlling the charging piles currently charging in the charging station to charge at half of the current power; or controlling the charging piles in the charging station whose remaining charging time does not exceed the preset charging time to terminate charging; or controlling the charging piles currently charging to terminate charging, and controlling cars that have been parked for more than the preset parking time T not to charge. Example 2

[0033] A method for controlling orderly charging of an electric vehicle comprises the following steps:

[0034] S1. The electric vehicle is connected to the charging pile, and the charging pile recognizes the electric vehicle and establishes a communication connection;

[0035] S2. Obtain the current SOC value through the electric vehicle BMS, obtain the currently available total grid power and grid frequency fluctuation range from the control terminal, and analyze the charging needs of the electric vehicle, including the required charging amount and expected charging time;

[0036] S3. Calculate the charging time slot based on the SOC of the electric vehicle and the available power of the grid, including the charging start time, end time and charging power;

[0037] S4. Arrange the calculated charging time slots in chronological order to form a charging plan. The control terminal sends a specific charging duration to each charging pile. The target voltage for each target charging stage within the preset total charging duration is calculated. The charging duration for each stage is the ratio of the target charging voltage to the initial charging voltage multiplied by the percentage of the total charging duration.

[0038] S5. The charging control module starts charging according to the charging plan and monitors the charging process in real time, including parameters such as current, voltage, and temperature. The total charging time is divided into four stages. In the first stage, the charging time is 5%-10%, the current gradually increases from 0A to 100A, and the voltage increases slowly with the increase of current. The target battery voltage every 100 milliseconds in the first stage is calculated based on the voltage increase rate. The corrected charging current for this period is calculated based on the difference between the actual battery voltage and the target voltage in the previous period. Corrected charging current = (target voltage - actual voltage) × battery cell capacitance × 0.5A. In the second stage, 10%-30%, the current is in constant current mode, 100A, and the voltage rises slowly with the increase of current. The target battery voltage for the period is calculated based on the voltage increase rate. The corrected charging current for the period is calculated based on the difference between the actual battery voltage and the target voltage in the previous period. In the third stage, 30%-60%, the charging current drops from 100A to 50A, and the voltage drops slowly as the current decreases. The target battery voltage for the period is calculated based on the voltage reduction rate. In the 30% stage, the current reduction rate is linear. The corrected charging current for the period is calculated based on the difference between the actual battery voltage and the target voltage in the previous period. In the fourth stage, greater than 60%, the charging current is in constant voltage mode and maintained at a constant voltage of 40V. The corrected charging current for the period is calculated based on the difference between the actual battery voltage and the target voltage in the previous period.

[0039] S6. Dynamically adjust the charging plan based on the grid conditions, EV BMS feedback, and charging pile status. If the grid load changes or the EV charging demand changes, recalculate the charging time slot and update the charging plan.

[0040] S7. After charging is completed, stop charging and disconnect the electric vehicle, calculate the charging amount, and display or send a charging report to the user.

[0041] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. An orderly charging control system for electric vehicles, characterized in that: It includes a charging pile and a control terminal, the control terminal is electrically connected to the charging pile, and the charging pile includes: an electric vehicle SOC acquisition module, a charging power acquisition module, and a charging time slot acquisition module. The electric vehicle SOC acquisition module is used for the electric vehicle onboard machine to obtain the electric vehicle SOC from the electric vehicle battery management system every 10 minutes; the charging power acquisition module is used to obtain the corresponding total available power of the power grid within the power grid frequency fluctuation range from the control terminal every 5 minutes; the charging time slot acquisition module is used to obtain the charging time slot according to the data obtained by the electric vehicle SOC acquisition module and the charging power acquisition module, the charging time slot includes time and charging power, and the charging time slots are arranged in chronological order to form a charging process; the charging control module is used to charge the electric vehicle battery in the order of the charging time slots.

2. An orderly charging control system for electric vehicles according to claim 1, characterized in that: The charging time slot acquisition module is used to acquire the charging time slot corresponding to the parking period of the electric vehicle. During the parking period of the electric vehicle, if the grid frequency exceeds the range of the total available grid power obtained by the charging power acquisition module, the charging power is adjusted according to a preset strategy to obtain a new charging time slot.

3. An orderly charging control system for electric vehicles according to claim 2, characterized in that: The charging time slot acquisition module is used to take time 0 as the starting time and 24 hours as the cycle, and divide the entire cycle into six time periods of 0-4, 4-8, 8-12, 12-16, 16-20 and 20-24 every 4 hours, set the SOC interval [Si-1, Si] according to the time period, i is the time period identifier, i=1, 2, 3, 4, 5, 6, and obtain the initial charging time slots according to the SOC intervals corresponding to the 6 time periods.

4. The electric vehicle orderly charging control system according to claim 1, characterized in that: The electric vehicle orderly charging system also includes a power grid frequency monitoring module, which is used to monitor the power grid frequency fluctuation range and provide the charging power acquisition module with the total power available from the power grid according to the power grid frequency fluctuation range.

5. The electric vehicle orderly charging control system according to claim 1, characterized in that: The charging time slot acquisition module is used to determine the charging state of the current charging time slot as a standby state when the available total power interval of the charging station where the electric vehicle is parked exceeds the available total power interval corresponding to the current charging time slot; and when the parking period of the electric vehicle corresponds to multiple available total power intervals, the initial charging time slot is determined according to the SOC size of the electric vehicle.

6. An orderly charging control system for electric vehicles according to claim 5, characterized in that: When the total available charging power of the charging station is greater than the total charging power of the electric vehicle battery + the power requirement corresponding to the remaining charging time of the charging pile currently being charged, the remaining charging power is halved to obtain the available power required for the remaining charging time of the charging pile currently being charged. If the current charging power is not satisfied, the charging pile currently being charged is controlled to charge at half of the current power; or if the current charging power is not satisfied, the current charging pile is controlled to end charging.

7. An orderly charging control system for electric vehicles according to claim 6, characterized in that: The control terminal is used to monitor the real-time power of the charging station load. When the real-time power of the charging station load exceeds the corresponding preset threshold, power limitation is performed. The power limitation includes: controlling the charging piles being charged in the charging station to charge at half of the current power; or controlling the charging piles in the charging station whose remaining charging time does not exceed the preset charging time to end charging; or controlling the charging piles being charged to end charging, and controlling the cars that have been parked for more than the preset parking time T not to charge.

8. An orderly charging control method for electric vehicles, based on the orderly charging control system for electric vehicles according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: obtaining the SOC of the electric vehicle; obtaining the total available power of the power grid corresponding to the power grid frequency fluctuation range from the control terminal every 5 minutes; obtaining a charging time slot according to the SOC of the electric vehicle and the total available power of the power grid, wherein the charging time slot includes time and charging power; and charging the battery of the electric vehicle based on the order of the charging time slots.

9. The method for controlling orderly charging of electric vehicles according to claim 8, characterized in that: The electric vehicle battery is charged based on the sequence of charging time slots. The specific charging time is sent to each charging pile through the control terminal, and the target charging voltage for each target stage under the preset total charging time is calculated. The charging time for each stage is the ratio of the charging target voltage to the initial charging voltage multiplied by the percentage of the total charging time.

10. The method for controlling orderly charging of electric vehicles according to claim 9, characterized in that: The total charging time is divided into 4 stages; in the first stage, charging time of 5%-10%, the current gradually increases from 0A to 100A, and the voltage increases slowly with the increase of current. The target battery voltage every 100 milliseconds in the first stage is calculated according to the voltage increase rate. The corrected charging current of this period is calculated according to the difference between the actual battery voltage and the target voltage in the previous period. Corrected charging current = (target voltage-actual voltage) × battery cell capacitance × 0.5A. In the second stage, 10%-30%, the current is in constant current mode, 100A, and the voltage rises slowly with the increase of current. The target battery voltage of the period is calculated according to the voltage increase rate. The difference between the actual battery voltage and the target voltage in the previous period is used to calculate the corrected charging current for this period. In the third stage, 30%-60%, the charging current drops from 100A to 50A, and the voltage drops slowly as the current decreases. The target battery voltage for the period is calculated based on the voltage reduction rate. In the 30% stage, the current reduction rate is linear. The corrected charging current for this period is calculated based on the difference between the actual battery voltage and the target voltage in the previous period. In the fourth stage, greater than 60%, the charging current is in constant voltage mode and maintained at a constant voltage of 40V. The corrected charging current for this period is calculated based on the difference between the actual battery voltage and the target voltage in the previous period.

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