Disclosure of Invention
In order to solve the above-mentioned problems in the background art, the present invention provides an ordered charging control system and method for an electric vehicle.
In order to achieve the above purpose, the present invention adopts the following technical scheme:
The ordered charging control system of the electric automobile comprises a charging pile and a control terminal, wherein the control terminal is electrically connected with the charging pile, the charging pile comprises an electric automobile SOC acquisition module, a charging power acquisition module, a charging time slot acquisition module and a charging control module, the electric automobile SOC acquisition module is used for acquiring an electric automobile SOC from an electric automobile battery management system by an electric automobile vehicle-mounted machine every 10 minutes, the charging power acquisition module is used for acquiring the available total power of a power grid corresponding to a power grid frequency fluctuation interval from the control terminal every 5 minutes, the charging time slot acquisition module is used for acquiring charging time slots according to data acquired by the electric automobile SOC acquisition module and the charging power acquisition module, the charging time slots comprise time and charging power, the charging time slots are arranged in time sequence to form a charging process, and the charging control module is used for charging an electric automobile battery according to the sequence of the charging time slots.
Preferably, the charging time slot obtaining module is configured to obtain a charging time slot corresponding to the electric vehicle parking period, and in the electric vehicle parking period, if the power grid frequency exceeds the range of the available total power interval of the power grid obtained by the charging power obtaining module, adjust the charging power according to a preset strategy to obtain a new charging time slot.
Preferably, the charging time slot obtaining module is configured to divide the whole period into six periods of 0-4 hours, 4-8 hours, 8-12 hours, 12-16 hours, 16-20 hours and 20-24 hours every 4 hours with 0 time as a starting time and 24 hours as a period, set SOC intervals [ Si-1, si ] according to the period, i is a period identifier, i=1, 2,3,4,5,6, and obtain initial charging time slots according to SOC intervals corresponding to 6 periods.
Preferably, the ordered charging system further comprises a grid frequency monitoring module, wherein the grid frequency monitoring module is used for monitoring a grid frequency fluctuation interval, and providing the available total power of the grid for the charging power acquisition module according to the grid frequency fluctuation interval.
Preferably, the charging time slot obtaining module is configured to determine the initial charging time slot according to the SOC size of the electric vehicle 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 the charging state of the current charging time slot is a standby state and when the electric vehicle parking time interval corresponds to the multiple available total power intervals.
Preferably, when the total available charging power of the charging station is greater than the total charging power of the battery of the electric vehicle and 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 by 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 according to 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.
Preferably, the control terminal is used for monitoring the real-time power of the charging station load, and when the real-time power of the charging station load exceeds a corresponding preset threshold value, the power limitation is carried out, wherein the power limitation comprises the steps of controlling a charging pile which is being charged in the charging station to charge according to half of the current power, or controlling the charging pile which is being charged to charge for a period of time which does not exceed the preset charging time to charge, or controlling the charging pile which is being charged to charge, and controlling the automobile which is parked for a period of time which exceeds the preset parking time T to not charge.
On the other hand, the invention also provides an ordered charging control method of the electric automobile, which comprises the following steps of obtaining the SOC of the electric automobile through a system, obtaining the available total power of a power grid corresponding to the power grid frequency fluctuation interval from the control terminal every 5 minutes, obtaining a charging time slot according to the SOC of the electric automobile and the available total power of the power grid, wherein the charging time slot comprises time and charging power, and charging the battery of the electric automobile based on the sequence of the charging time slots.
Preferably, the electric automobile battery is charged based on the sequence of charging time slots, a specific charging duration is issued to each charging pile through the control terminal, the target voltage charged in each target stage under the preset total charging duration is calculated, and the charging duration of each stage is the ratio of the charging target voltage to the initial charging voltage multiplied by the percentage of the total charging duration.
The method comprises the steps of dividing a preset total charging time into 4 stages, gradually increasing current from 0A to 100A in the first stage and charging 5% -10% in time, gradually increasing voltage along with current increase, calculating to obtain a target battery voltage every 100 milliseconds in the first stage according to a voltage increase rate, calculating a corrected charging current in the first stage according to a difference value between the actual battery voltage and the target voltage in the last stage, wherein the corrected charging current= (target voltage-actual voltage) ×battery cell Rong Zu ×0.5A, calculating a corrected charging current in the second stage and 10% -30% in a constant current mode, gradually increasing the voltage along with the current increase, calculating a time-stage target battery voltage according to a voltage increase rate, calculating a corrected charging current in the last stage according to a difference value between the actual battery voltage and the target voltage in the last stage, calculating a corrected charging current in the third stage and 30% -60%, and the third stage according to a difference value between the actual battery voltage in the last stage and the current in the 30% stage, and the corrected charging current in the fourth stage is larger than the actual voltage in the first stage and the constant current in the third stage, and the corrected charging current in the third stage is calculated to be 40% -60%.
Compared with the prior art, the invention has the beneficial effects that:
1. According to the invention, the charging time slots are obtained according to the SOC of the electric vehicle and the total power available by the power grid, the battery of the electric vehicle is charged based on the sequence of the charging time slots, and all time slots of the cell charging pile can be fully utilized to complete the charging of the electric vehicle as much as possible, so that the charging interference among all time slots in the charging station is reduced, the influence on the power grid frequency is minimum, the impact on the power grid is small, the power grid pressure is relieved, the safety of the power grid is further ensured, and the adjustment and distribution of the total power in the charging station are more reasonable.
2. According to the invention, the preset total charging time is divided, and the charging process is optimized by controlling the charging current and the charging voltage of each stage, so that the safety and the efficiency of battery charging are ensured. By applying different charging modes and correction strategies at different stages, the charging time is reduced, the charging speed is improved, and meanwhile, damage to the battery is avoided.
Detailed Description
The technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Example 1
Referring to fig. 1, the embodiment of the invention provides an ordered charging control system for an electric automobile, which comprises a charging pile and a control terminal, wherein the control terminal is electrically connected with the charging pile, and the charging pile comprises an electric automobile SOC acquisition module, a charging power acquisition module, a charging time slot acquisition module and a charging control module. The system comprises an electric vehicle SOC acquisition module, a charging time slot acquisition module and a charging control module, wherein the electric vehicle-mounted machine is used for acquiring the electric vehicle SOC from an electric vehicle battery management system every 10 minutes, the charging power acquisition module is used for acquiring the available total power of a power grid corresponding to a power grid frequency fluctuation interval from a control terminal every 5 minutes, so that the system knows the power supply capacity of the current power grid to reasonably arrange the charging power, the charging time slot acquisition module is used for acquiring charging time slots according to data acquired by the electric vehicle SOC acquisition module and the charging power acquisition module, the charging time slots comprise time and the charging power, the charging time slots are arranged in time sequence to form a charging process, the charging process is ensured to be orderly carried out, the charging control module is used for charging the electric vehicle battery according to the information provided by the charging time slot acquisition module, and the charging process is intelligently controlled to realize the orderly charging of the electric vehicle. In order to further achieve the object, the embodiment of the invention provides an ordered charging control system for an electric automobile, wherein the charging time slot acquisition module is used for acquiring a charging time slot corresponding to an electric automobile parking time slot, and in the electric automobile parking time slot, if the power grid frequency exceeds the range of the available total power interval of the power grid acquired by the charging power acquisition module, the charging power is adjusted according to a preset strategy to acquire a new charging time slot, and the new charging time slot is sent to the charging control module. The new charging time slot may reflect the adjusted charging power and possible charging time variation, and the preset policy may be to reduce the charging power to adapt to the power supply capability of the cell power grid, or to increase the charging power when the power supply capability of the power grid is restored, and at the same time, in the parking period of the electric vehicles, the charging time slot acquisition module may determine, according to the SOC requirement of the electric vehicles and the total power available for the power grid, an initial charging time slot of each electric vehicle, including a time when charging starts and a time when charging ends, and the charging power in each time slot.
Further, the charging time slot obtaining module dynamically adjusts the charging time slot by integrating 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 of the charging station and the charging requirement of the user, and the specific steps of dynamically adjusting the charging time slot are as follows:
1. and initializing a charging time slot, namely allocating an initial charging time slot for each electric automobile, and based on the SOC and the charging requirement.
2. Calculating total required power:,
3. And adjusting the charging time slot, namely if Ptotal_demand≤Pgrid is reached, charging all the electric vehicles according to the preset charging time length. If Ptotal_demand>Pgrid, the charging slots need to be adjusted to accommodate the power supply capacity of the grid.
4. Dynamic adjustment, namely, for each electric automobile, calculating an adjustment factor Ki of a charging time slot of the electric automobile:× The adjusted charging time slot Ti' is Ti′=Ki×Ti.
5. Correction charging current Icorrection,i = (target voltage-actual voltage) ×battery cell Rong Zu ×0.5A is calculated from the difference between the actual voltage and the target voltage for each charging stage.
6. And updating a charging strategy, namely repeating the steps 2-5 according to the real-time power supply capacity of the power grid and the SOC change of the electric automobile, and dynamically adjusting the charging time slot and the charging current.
7. The adjusted charging time slot Ti' and the corrected charging current Icorrection,i are output.
The input parameters to be described are as follows:
SOCi the current SOC of the ith electric automobile;
Preq,i the charging power requirement of the ith electric automobile;
pgrid, the total power available for the power grid;
n, the number of charging piles of the charging station;
ttotal total charging time;
ti the preset charging time of the ith electric automobile.
In order to further achieve the object, the embodiment of the invention provides an ordered charging control system for an electric automobile, wherein the charging time slot acquisition module is used for dividing the whole period into six time slots of 0-4 hours, 4-8 hours, 8-12 hours, 12-16 hours, 16-20 hours and 20-24 hours every 4 hours with the starting time of 0 time and the period of 24 hours, setting SOC intervals [ Si-1, si ] according to the time slots, wherein i is a time slot identifier, and respectively acquiring initial charging time slots according to the SOC intervals corresponding to 6 time slots. In order to further achieve the object, the embodiment of the invention provides an ordered charging control system for an electric automobile, which further comprises a power grid frequency monitoring module, wherein the power grid frequency monitoring module is used for monitoring a power grid frequency fluctuation interval and providing the available total power of a power grid for the charging power acquisition module according to the power grid frequency fluctuation interval. In order to further achieve the object, the embodiment of the invention provides an ordered charging control system for an electric vehicle, wherein the charging time slot acquisition module is used for determining an initial charging time slot according to the SOC (state of charge) size of the electric vehicle when an available total power interval of a charging station where the electric vehicle is parked exceeds an available total power interval corresponding to a current charging time slot, and the charging state of the current charging time slot is a standby state. In order to further achieve the object, the embodiment of the invention provides an ordered charging control system for an electric vehicle, when the total available charging power of the charging station is greater than the total charging power of a battery of the electric vehicle and the power requirement corresponding to the remaining charging time of a charging pile currently being charged, the remaining charging power is halved to obtain the available power required by the remaining charging time of the charging pile currently being charged, if the current charging power is not met, the charging pile currently being charged is controlled to be charged according to half of the current power, and if the current charging power is not met, the charging of the current charging pile is controlled to be ended. In order to further achieve the aim, the embodiment of the invention provides an ordered charging control system for an electric automobile, which further comprises a control terminal, wherein the control terminal is used for monitoring the real-time power of a charging station load, and when the real-time power of the charging station load exceeds a corresponding preset threshold value, the control terminal is used for carrying out power limitation, and the power limitation comprises the steps of controlling a charging pile which is being charged in the charging station to charge according to half of the current power, or controlling the charging pile which is not being charged in the charging station to charge until the residual charging time exceeds the preset charging time is ended, or controlling the charging pile which is being charged to charge until the parking time exceeds the preset parking time T to charge.
Example 2
An ordered charging control method of an electric automobile comprises the following steps:
S1, connecting an electric automobile to a charging pile, and identifying the electric automobile by the charging pile and establishing communication connection;
S2, acquiring a current SOC value through an electric vehicle BMS, acquiring the total power of a currently available power grid and a power grid frequency fluctuation interval from a control terminal, and analyzing the charging demand of the electric vehicle, wherein the charging demand comprises a required charging amount and an expected charging time;
s3, calculating a charging time slot according to the SOC of the electric automobile and the available power of the power grid, wherein the charging time slot comprises charging start time, charging end time and charging power;
s4, arranging the calculated charging time slots in time sequence to form a charging plan, issuing specific charging time to each charging pile through a control terminal, and calculating the target voltage charged in each target stage under the preset total charging time length, wherein the charging time length 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 length;
S5, the charging control module starts to execute charging according to a charging plan, monitors a charging process in real time, wherein the charging process comprises parameters such as current, voltage, temperature and the like, and the total charging time length is divided into 4 stages; the method comprises the steps of a first stage, charging for 5% -10% of time, gradually increasing current from 0A to 100A, slowly increasing voltage along with current increase, calculating to obtain target battery voltage every 100 milliseconds in the first stage according to the voltage increase rate, calculating to obtain corrected charging current in the first stage according to the difference value between the actual battery voltage and the target voltage in the previous stage, calculating to obtain corrected charging current in the first stage, wherein the corrected charging current= (target voltage-actual voltage) x battery cell Rong Zu x 0.5A, calculating to obtain corrected charging current in the second stage, wherein the current in the first stage is in a constant current mode, the current in the second stage, 10% -30% of stage is in a constant current mode, the voltage slowly rises along with current increase, calculating to obtain corrected charging current in the first stage according to the voltage increase rate, calculating to obtain corrected charging current in the first stage according to the difference value between the actual battery voltage and the target voltage in the previous stage, and the charging current is reduced from 100A to 50A, the voltage slowly drops along with current, calculating to obtain corrected charging current in the first stage according to the difference value between the actual battery voltage and the target voltage in the previous stage, and the current in the first stage, calculating to obtain corrected charging current in the fourth stage, the charging current in the fourth stage, greater than 60% is in the constant voltage and the constant voltage is kept at constant voltage in the constant voltage stage, and the corrected charging current in the first stage is calculated to be in the constant current in the constant voltage stage;
S6, dynamically adjusting a charging plan according to the power grid condition, BMS feedback of the electric vehicle and the state of the charging pile, and if the power grid load changes or the charging demand of the electric vehicle changes, recalculating a charging time slot and updating the charging plan;
And S7, stopping charging and disconnecting the electric vehicle after the charging is completed, settling the charged amount, and displaying or sending a charging report to a user.
The foregoing is only a preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art, who is within the scope of the present invention, should make equivalent substitutions or modifications according to the technical scheme of the present invention and the inventive concept thereof, and should be covered by the scope of the present invention.