Safety regulation method, device and system for direct current charging pile considering battery characteristics

Abstract

The application relates to the technical field of charging pile adjustment, in particular to a DC charging pile safety adjustment method, device and system considering battery characteristics, the method comprising the following steps: acquiring daily load data of a power grid in a region where a DC charging pile is located, and the charging time length of each charging vehicle connected to the DC charging pile; according to the regularity characteristics of the daily load data, the total charging power borne by the DC charging pile, and the charging time length of each charging vehicle connected to the DC charging pile in different charging stages, and in combination with the time interval and load difference between each time point of the previous day and the first load peak value after the time point, the safety adjustment coefficient of the DC charging pile at each time point of the day is acquired, and then it is judged whether the DC charging pile can safely adjust the charging parameters of the charging vehicle. According to the application, the characteristics of the power grid load data and the charging characteristics of the vehicle battery are analyzed, so that the stable operation of the power grid is ensured under the condition that the power supply of the DC charging pile is normal.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of charging pile adjustment, in particular to a DC charging pile safety adjustment method, device and system considering battery characteristics. BACKGROUND

[0002] In recent years, new energy electric vehicles have developed rapidly, and the demand for charging piles has also increased year by year, especially the vigorous development and promotion of pure electric buses, which has continuously improved the requirements for charging pile stability, pile function diversity and pile cost. In the existing DC charging pile control process, the charging control is mainly performed by receiving the messages of the charging bus battery (such as BSM, CCS, BCL messages), and the charging control is performed according to the message information. However, in the process of regulating a local area, the carrying pressure of the power grid is different at different times, and the use of the charging pile is also different. When the power grid load is high or there are many vehicles charging at the same time, only relying on the message information of the charging vehicle battery to control the charging power may bring a large amount of load growth to the power grid, increase the load peak-valley difference of the micro-grid, and bring a great impact on the load balance of the power grid, thereby destroying the voltage and the stability of the entire power system. For example, the departure time and driving path of the bus are relatively high, which may cause some shifts to run simultaneously and enter the charging station for charging, and at the same time, the area covered by the power grid may also contain civil power, so the relative load is high in the morning, noon and evening, and finally the power grid load may increase greatly in a short time.

[0003] In the prior art, when coordinating the charging pile and the power grid system, the DC charging pile cannot select suitable charging parameter adjustment periods for each charging vehicle based on the real-time fluctuation of the power grid load, and adjusting the charging parameters of the vehicle in a high load period will cause the power grid to operate in overload. In the process of adjusting the charging parameters, the prior art usually only allocates according to the fixed parameters of the charging pile, and it is difficult to adjust the charging parameters of the charging vehicle in time when the power grid load fluctuates. For example, when the power grid load increases sharply at a certain time, the charging power of the vehicle cannot be quickly reduced, which may cause the power grid to frequently fluctuate in voltage, reduce the overall power supply stability, and cannot ensure the power grid is not impacted while ensuring the charging efficiency. SUMMARY

[0004] In order to solve the above technical problems, the purpose of the present application is to provide a DC charging pile safety adjustment method, device and system considering battery characteristics, and the technical solution adopted is as follows:

[0005] In a first aspect, the present application provides a DC charging pile safety adjustment method considering battery characteristics, which comprises the following steps:

[0006] obtain daily load data of a power grid in which the DC charging pile is located, and charging time length and BCL message of each charging vehicle connected to the DC charging pile at each time point;

[0007] obtain an adjustable coefficient of the DC charging pile at each time point of the day according to the similarity of load data of the DC charging pile in the same time period before the same time point of the day and the previous day, and the difference between the dispersion of all load data of the same time point of the day and the previous day, and the sum of charging power borne by the DC charging pile at the same time point of the day;

[0008] obtain a charging time length coefficient of each charging vehicle of the DC charging pile at each time point of the day according to the charging time length of each charging vehicle connected to the DC charging pile at each time point of the day and the BCL message at the corresponding time point, obtain a safety adjustment compensation coefficient of the DC charging pile at each time point of the day according to the time interval between each time point of the day and the first load peak value after the time point, and the difference between the load data at each time point of the day and the first load peak value after the same time point of the previous day, and obtain a safety adjustment coefficient of the DC charging pile at each time point of the day by combining the adjustable coefficient at each time point, and then judge whether the DC charging pile can safely adjust the charging parameter of the charging vehicle at each time point of the day.

[0009] Preferably, the calculation formula of the adjustable coefficient of the DC charging pile at each time point of the day is: ; in the formula, is the adjustable coefficient of the DC charging pile at the i th time point of the day, is the cosine similarity between the sub-load sequence at the i th time point of the day and the previous day, , are the range of all power grid load data of the day and the previous day up to the i th time point, respectively, is the sum of charging power demand borne by the DC charging pile at the i th time point of the day.

[0010] Preferably, the sub-load sequence at each time point refers to a sequence composed of load data of a preset time length before each time point in chronological order.

[0011] Preferably, the process of obtaining the sum of charging power demand borne by the DC charging pile at each time point is as follows: obtaining voltage demand and current demand in the BCL message of all charging vehicles connected to the DC charging pile at each time point, taking the product of voltage demand and current demand of each charging vehicle at each time point as the charging power of each charging vehicle, and taking the sum of charging power of all charging vehicles of the DC charging pile at each time point as the sum of charging power demand borne by the DC charging pile at each time point.

[0012] Preferably, the process for obtaining the charging duration coefficient of each charging vehicle at each time of the day by the direct current charging pile is as follows: when the charging mode field in the BCL packet of each charging vehicle at each time of the day by the direct current charging pile is 010B, the charging duration coefficient is the reciprocal of the charging duration of each charging vehicle at each time of the day by the direct current charging pile; when the charging mode field in the BCL packet of each charging vehicle at each time of the day by the direct current charging pile is 001B, the charging duration coefficient is the charging duration of each charging vehicle at each time of the day by the direct current charging pile.

[0013] Preferably, the calculation formula of the safety adjustment compensation coefficient of the direct current charging pile at each time of the day is as follows: ; in the formula, is the safety adjustment compensation coefficient of the direct current charging pile at the i th time of the day, is the absolute difference between the i th time of the previous day and the sampling time corresponding to the first load peak value after the i th time, is the charging duration coefficient of the u th charging vehicle at the i th time of the day by the direct current charging pile, U is the total number of corresponding charging vehicles at the i th time of the day by the direct current charging pile, is the power grid load data at the i th time of the day, is the first load peak value data after the i th time of the previous day, exp( ) is an exponential function with natural constant e as the base, is a preset constant.

[0014] Preferably, the safety adjustment coefficient of the direct current charging pile at each time of the day is the normalized result of the product of the adjustable coefficient and the safety adjustment compensation coefficient of the direct current charging pile at each time of the day.

[0015] Preferably, the specific process for judging whether the direct current charging pile can perform safety adjustment on the charging parameters of the charging vehicle at each time of the day is as follows: when the safety adjustment coefficient of the direct current charging pile at any time of the day is greater than or equal to a preset segmentation threshold, it is judged that the direct current charging pile can perform safety adjustment on the charging parameters of the charging vehicle at the time; otherwise, it is judged that the direct current charging pile cannot perform safety adjustment on the charging parameters of the charging vehicle at the time.

[0016] In a second aspect, the embodiments of the present application provide a direct current charging pile safety adjustment device considering battery characteristics, which comprises a data acquisition module, an adjustment analysis module, and a safety adjustment judgment module.

[0017] The data acquisition module is used to acquire the daily load data of the power grid in the region where the direct current charging pile is located, the charging duration of each charging vehicle connected to the direct current charging pile, and the BCL packet of each charging vehicle at each time;

[0018] The adjusting analysis module is configured to obtain an adjustable coefficient of the DC charging pile at each time of the day based on regularity of daily load data of the DC charging pile and charging power borne by the DC charging pile.

[0019] The safe adjusting discrimination module is configured to obtain a safe adjusting coefficient of the DC charging pile at each time of the day based on charging time length of each charging vehicle connected to the DC charging pile, the adjustable coefficient at each time of the day, and time interval and load difference between the same time of the previous day and the first load peak period after the same time, and to further judge whether the DC charging pile can safely adjust the charging parameter of the charging vehicle.

[0020] In a third aspect, the embodiments of the present application further provide a DC charging pile safe adjusting system considering battery characteristics, which comprises a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the steps of the DC charging pile safe adjusting method considering battery characteristics according to any one of the above aspects when executing the computer program.

[0021] As can be seen from the above embodiments, the DC charging pile safe adjusting method, device and system considering battery characteristics provided by the embodiments of the present application have at least the following beneficial effects:

[0022] The present application calculates the safe adjusting coefficient of the DC charging pile at each time by analyzing charging power demand of each vehicle and charging time length of different charging stages of the single DC charging pile in the process of charging the vehicle, considering regular variation characteristics of the power grid load and data characteristics of the upcoming load peak, and power grid load data at each time, to judge whether the current DC charging pile can safely adjust the charging parameter of the charging vehicle or will affect the power grid, thereby ensuring stable operation of the power grid under the condition of ensuring normal power supply of the DC charging pile. The problem that the traditional fixed threshold-based method for safely adjusting and controlling the DC charging pile cannot adjust according to dynamic power grid load variation characteristics and vehicle battery charging demand variation, thereby easily causing impact on the power grid and affecting stability of the power grid in the adjusting process is solved. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more clearly illustrate the technical solutions and advantages of the embodiments of the present application or the prior art, the drawings needed in the embodiments or the prior art description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creative labor.

[0024] Figure 1A step flow chart of the safety adjustment method of the DC charging pile considering the characteristics of the battery is provided for an embodiment of the present application.

[0025] Figure 2 A structural schematic diagram of the safety adjustment device of the DC charging pile considering the characteristics of the battery is provided for an embodiment of the present application. DETAILED DESCRIPTION

[0026] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined purposes, the safety adjustment method, device and system of the DC charging pile considering the characteristics of the battery according to the present application, the specific implementation, structure, features and effects thereof are described in detail as follows in combination with the drawings and preferred embodiments. In the following description, different "one embodiment" or "another embodiment" do not necessarily refer to the same embodiment. In addition, the specific features, structures or characteristics in one or more embodiments can be combined in any suitable form.

[0027] Unless otherwise defined and limited, such as the term "comprise", "include" or any other variant thereof is intended to cover non-exclusive inclusion, so that the circuit structure, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such article or device. Without more limitation, the element limited by the statement "including one" does not exclude the presence of another identical element in the article or device including the element. In addition, the term "and / or" used herein includes any and all combinations of one or more related listed items. All technical and scientific terms used herein have the same meaning as understood by those skilled in the art to which the present application belongs.

[0028] The specific scheme of the safety adjustment method, device and system of the DC charging pile considering the characteristics of the battery provided by the present application is specifically described below in combination with the drawings.

[0029] Please refer to Figure 1 which shows the step flow chart of the safety adjustment method of the DC charging pile considering the characteristics of the battery provided by an embodiment of the present application, which includes the following steps:

[0030] Step one: Obtain the daily load data of the power grid in the area where the DC charging pile is located, and the charging time and BCL message of each charging vehicle connected to the DC charging pile at each time.

[0031] The current DC charging pile area connected to the power grid load data is obtained every interval time T through the charging pile cloud platform, and the charging time of each charging vehicle of the current DC charging pile. The power grid load data sequence is obtained by arranging the power grid load data in time sequence every day (in this scheme, the load voltage data in the power grid is mainly used to represent the load condition of the power grid). Further, for a single DC charging pile, when a vehicle is charging, the voltage demand, current demand and charging mode data in the BCL message of each charging vehicle are obtained according to the message data transmitted by the vehicle battery BMS. In this embodiment, T=0.1s.

[0032] Step two: According to the similarity of the load data of the DC charging pile in the same time period before the same time of the same day and the previous day, and the difference between the dispersion degree of all load data before the same time of the same day and the previous day, and the sum of the charging power borne by the DC charging pile at the same time of the same day, the adjustable coefficient of the DC charging pile at each time of the same day is obtained.

[0033] Since the output adjustment of the charging pile is usually adjusted when there is a charging vehicle, if there is no vehicle charging, the traditional charging adjustment mode is used for control adjustment. This embodiment takes a single DC charging pile with at least one vehicle charging as an example for the following control adjustment.

[0034] Usually, when the DC charging pile receives the charging request message from the vehicle battery BMS, the DC charging pile controller will immediately adjust the current charging demand according to the relevant information in the message, such as voltage demand, current demand, etc., and then output the corresponding current and voltage to meet the charging demand of the vehicle. However, due to the large fluctuation of the load of the power grid in different periods, and the charging pile itself may also face various charging situations, such as multi-gun different power charging (multiple vehicles with different charging demands charging at the same time), charging and discharging at the same time, etc., therefore, only according to the battery message situation to adjust the charging pile, it may cause the charging pile power distribution to be too high or too low, affecting the overall power grid balance, such as multiple charging piles with multi-gun charging at the same time in the high load period of the power grid, which will cause the power grid to be overloaded, thereby possibly impacting the stability of the power grid, therefore, the current charging state of the charging pile and the actual load change of the power grid need to be analyzed to determine the current adjustment.

[0035] Specifically, for the power grid of a local area, the overall load condition change has certain regularity, such as the electricity consumption peak usually occurs in the early, middle and late three time periods, the collective charging of each shift bus, the batch charging and the like, and in the same local area, in order to be able to guarantee the normal electricity consumption of the power grid coverage area, the power grid has certain redundancy design, if there is no special event (such as the surge of the number of bus vehicles due to the addition of bus routes, the collective charging of bus vehicles from other operation areas to the power grid coverage area and the like), the overall electricity consumption is relatively stable in a short period, the power grid change condition in each time period is approximately, and the power supply of the direct current charging pile is also relatively sufficient, so the safety of the direct current charging pile during the adjustment is also high. Further, for the direct current charging pile itself, a single charging pile can perform single-gun or multi-gun charging, the more vehicles charged by a single charging pile, the more power provided by the charging pile, the greater the required power supply power, and then the adjustable space of the direct current charging pile is smaller; on the contrary, when the vehicles charged by the charging pile are less, the overall power supply power is smaller, and then the adjustable degree is higher in the subsequent adjustment process of the load by the direct current charging pile.

[0036] To express the above features, taking the i-th sampling time of the day as an example, the sequence composed of the load data of a preset time length before the i-th time according to the time sequence order is recorded as the sub-load sequence of the i-th time, and the preset time length is 1 hour in this embodiment. Further, since the load condition change of the power grid has certain time regularity, the regularity degree of the power grid load data at the same time of the day can be judged according to the approximation degree of the sub-load sequence at the same time of the day and the previous day.

[0037] As a preferred embodiment, the adjustable coefficient of the direct current charging pile at each time of the day is obtained according to the similarity degree of the load data in the same time period before the same time of the day of the direct current charging pile of the day and the previous day, the difference between the dispersion degrees of all load data before the same time of the day of the day and the previous day, and the total charging power borne by the direct current charging pile at the same time of the day, for judging the adjustable degree of the direct current charging pile at each time of the day.

[0038] In this embodiment, the adjustable coefficient of the direct current charging pile at the i-th time of the day is recorded as , and the specific expression is: ; in the formula, is the adjustable coefficient of the direct current charging pile at the i-th time of the day, is the cosine similarity degree between the sub-load sequences at the i-th time of the day and the previous day, , are the ranges of all power grid load data of the day and the previous day up to the i-th time, respectively, The total sum of the charging power demands borne by the DC charging pile at the ith moment of the day. It should be noted that the total sum of the charging power demands borne by the DC charging pile at each moment is obtained by: obtaining the voltage demand and the current demand in the BCL message of all the charging vehicles connected to the DC charging pile at each moment, and combining the electrical power calculation formula, multiplying the voltage demand and the current demand of each charging vehicle at each moment to obtain the charging power of each charging vehicle, and summing the charging power of all the charging vehicles connected to the DC charging pile at each moment to obtain the total sum of the charging power demands borne by the DC charging pile at each moment.

[0039] The meaning of the relationship is: the closer the approximation degree of the sub-load sequence fluctuation characteristics of the DC charging pile on the current day and the previous day and the closer the current moment, the smaller the difference between the load range of the power grid on the current day and the previous day, and the smaller the total consumption of the charging power of the charging vehicles connected to the current DC charging pile, indicating that the power supply pressure faced by the current DC charging pile and the power grid is smaller, and the degree of safe adjustment of the DC charging pile is greater.

[0040] Step three: according to the charging time of each charging vehicle connected to the DC charging pile at each moment of the day and the BCL message at the corresponding moment, obtaining the charging time coefficient of each charging vehicle of the DC charging pile at each moment of the day, and combining the time interval between each moment of the previous day and the first load peak value after it, and the load data at each moment of the day and the difference between it and the first load peak value after the same moment of the previous day, obtaining the safe adjustment compensation coefficient of the DC charging pile at each moment of the day, and combining the adjustable coefficient at each moment, obtaining the safe adjustment coefficient of the DC charging pile at each moment of the day, and then judging whether the DC charging pile can adjust the charging parameters of the charging vehicle at each moment of the day.

[0041] For electric vehicle charging, the process actually includes three stages, namely constant current stage, constant voltage stage and trickle stage (constant voltage stage and trickle stage are 001B in BCL message). After the vehicle connects the charging pile through the charging gun, the BMS system of the vehicle battery will send a message to the pile end according to the actual battery condition, and the charging pile will modify the message content according to the message condition, usually first in the constant current stage (usually between 0% and 50% of the battery SOC), that is, the charging current is constant and keeps the maximum value, and the voltage and power gradually increase; further, when the battery SOC is about 50%, the battery BMS system modifies the message content, and the charging demand is modified to constant voltage charging, at this time the voltage keeps the maximum value, the current and power gradually decrease, finally when the battery SOC is 80%~100%, the charging pile will maintain a low current and voltage to maintain charging, mainly to balance the differences between the batteries of each vehicle and compensate for the self-discharge of the battery, and the power is very low, finally completing the charging of the vehicle.

[0042] In summary, in the early stage of the constant current phase and the late stage of the constant voltage phase, the actual charging power provided by the charging pile is relatively small. Only in the late stage of the constant current phase and the early stage of the constant voltage phase, the required power is high. Therefore, if the current DC charging pile is adjusted when the charging vehicles of the current charging pile are in the early stage of the constant current phase or the late stage of the constant voltage phase, the influence of the adjustment of the charging pile on the power grid is smaller, and the safety is higher.

[0043] Further, for the change of the load condition of the power grid, the load condition is different in different periods. There may be a non-load peak period at the current time, and after a relatively short period of time, it enters the peak period. Therefore, it is also necessary to combine and analyze the change of the load data of the power grid after the current time. If the load of the power grid at the current time is smaller than the load of the load peak period after the same time of the previous day, and the time interval of the first load peak period after the same time of the previous day is larger, the adjustment of the DC charging pile has less influence on the power grid.

[0044] In order to represent the above characteristics, for the power grid load data sequence of the previous day, all peak values in the sequence are obtained by using a peak value detection algorithm. All the obtained peak values represent all load peak periods of the previous day.

[0045] In summary, according to the charging time of each charging vehicle connected by the DC charging pile at each time of the day and the BCL message at the corresponding time, the charging time coefficient of each charging vehicle of the DC charging pile at each time of the day is obtained, which is used to represent the safe adjustment degree of the DC charging pile under the charging state of each charging vehicle at each time.

[0046] In this embodiment, the calculation formula of the charging time coefficient of each charging vehicle of the DC charging pile at each time of the day is: In the formula, is the charging time coefficient of the u-th charging vehicle of the DC charging pile at the i-th time of the day, is the charging time of the u-th charging vehicle of the DC charging pile at the i-th time of the day. It should be noted that 010B represents constant current charging, and 001B represents constant voltage charging.

[0047] The greater the value of is, the shorter the charging time of the charging vehicle in the constant current state of the DC charging pile at the i-th time, or the longer the charging time of the charging vehicle in the constant voltage state. It is represented that the charging power of the u-th charging vehicle of the DC charging pile at the i-th time is smaller, and the safe adjustment degree of the DC charging pile under the charging state of the charging vehicle at the time is higher.

[0048] As a preferred implementation, according to the charging time length coefficient of each charging vehicle of the direct current charging pile at each time of the day, in combination with the time interval between each time of the previous day and the first load peak value after the time, and the load data at each time of the day and the difference between the first load peak value after the same time of the previous day, the safety adjustment compensation coefficient of the direct current charging pile at each time of the day is obtained, which is used to represent the safe adjustment degree of the direct current charging pile at each time of the day.

[0049] In the embodiment, the safety adjustment compensation coefficient of the direct current charging pile at the i th time of the day is denoted as , and the specific expression is: ; in the formula, is the safety adjustment compensation coefficient of the direct current charging pile at the i th time of the day, is the absolute difference value of the i th time of the previous day and the sampling time corresponding to the first load peak value after the time, is the charging time length coefficient of the u th charging vehicle of the direct current charging pile at the i th time of the day, U is the total number of corresponding charging vehicles of the direct current charging pile at the i th time of the day, is the power grid load data at the i th time of the day, is the first load peak value data after the i th time of the previous day, exp( ) is an exponential function with natural constant e as the base, is a preset constant, which is used to prevent the denominator from being 0, and in the embodiment .

[0050] The meaning of the relationship is: the farther the same time of the previous day and the first peak value time after the time at the i th time of the day, and the smaller the current load data than the peak value after the same time of the previous day, and the smaller the current power grid load, the higher the safety of the direct current charging pile when adjusting at the current time, and the higher the adjustable degree.

[0051] Further, as a preferred implementation, according to the safety adjustment compensation coefficient and the adjustable coefficient of the direct current charging pile at each time of the day, the safety adjustment coefficient of the direct current charging pile at each time of the day is obtained, which is used to represent the safe adjustment degree of the direct current charging pile at each time of the day.

[0052] In the embodiment, the safety adjustment coefficient of the direct current charging pile at the i th time of the day is denoted as , and the specific expression is: ; in the formula, is the safety adjustment coefficient of the direct current charging pile at the i th time of the day, is the adjustable coefficient of the direct current charging pile at the i th time of the day, is the safety adjustment compensation coefficient of the direct current charging pile at the i th time of the day, The normalized function is used for normalization.

[0053] The greater the value of the safety adjustment coefficient of the direct current charging pile at the i th moment of the day, the smaller the impact of the direct current charging pile on the power grid when adjusting at the i th moment of the day, and the higher the safety of adjustment.

[0054] In the foregoing manner, the safety adjustment coefficient of the current direct current charging pile at all moments can be calculated. All safety adjustment coefficients are taken as inputs, a split threshold value of the safety adjustment coefficient is output by using a cross-validation manner, and is recorded as a preset split threshold value. When the safety adjustment coefficient of the direct current charging pile at any moment of the day is greater than or equal to the preset split threshold value, it is indicated that the impact of the direct current charging pile on the power grid is small when the direct current charging pile adjusts the charging parameters of the vehicle at the moment, and the adjustment can be safely performed. At this time, the charging pile adjusts the sizes of the voltage and the current in real time according to the BCL, BCS, CCS, BSM, BMV and other message information sent by each charging vehicle and the charging demand of each vehicle. When a set charging end condition is reached or a vehicle sends a charging termination message, the charging pile periodically sends a "charging pile termination charging message" and reduces the charging current. When the charging current is less than a preset current threshold value, the charging connection is disconnected. In the embodiment, the preset current threshold value is 5 A. Conversely, when the safety adjustment coefficient of the direct current charging pile at any moment of the day is less than the preset split threshold value, it is indicated that the direct current charging pile may have a great impact on the power grid when adjusting the charging parameters of the vehicle at the moment, and may cause the power grid to be unstable. At this time, the direct current charging pile delays the adjustment until the moment when the safety adjustment coefficient is greater than or equal to the preset split threshold value.

[0055] Please refer to Figure 2 , Figure 2 is a structural schematic diagram of a direct current charging pile safety adjustment device considering battery characteristics provided in the embodiment of the present application. In the embodiment, each unit included in the terminal is used to execute each step in the corresponding embodiment of the direct current charging pile safety adjustment method considering battery characteristics. Please refer to Figure 2 , the direct current charging pile safety adjustment device comprises a data acquisition module, an adjustment analysis module, and a safety adjustment discrimination module.

[0056] The data acquisition module is configured to acquire daily load data of a power grid in a region where a direct current charging pile is located, charging durations of each charging vehicle connected to the direct current charging pile, and BCL messages of each charging vehicle at each moment.

[0057] The adjustment analysis module is configured to acquire an adjustable coefficient of the direct current charging pile at each moment of the day based on regularity of daily load data of the direct current charging pile and charging power borne by the direct current charging pile.

[0058] The security adjustment judgment module is configured to obtain the security adjustment coefficient of the DC charging pile at each time of the day based on the charging time length of each charging vehicle connected to the DC charging pile, the adjustable coefficient at each time of the day, and the time interval and load difference between the same time of the previous day and the first load peak period after the same time, and then judge whether the DC charging pile can perform security adjustment on the charging parameter of the charging vehicle.

[0059] Based on the same inventive concept as the above method, the embodiments of the present application also provide a DC charging pile security adjustment system considering battery characteristics, which comprises a memory, a processor, and a computer program stored in the memory and running on the processor, and the processor implements the steps of the DC charging pile security adjustment method considering battery characteristics according to any one of the above embodiments when executing the computer program.

[0060] Each of the embodiments in the present application is described in a progressive manner, and the same or similar parts of each of the embodiments can be referred to each other. Each of the embodiments mainly describes the difference from other embodiments.

[0061] It should be noted that, unless otherwise specified and limited, terms such as "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that the circuit structure, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such article or device. Without more limitation, the element limited by the phrase "including a" does not exclude the presence of another identical element in the article or device including the element. In addition, the term "and / or" used herein includes any and all combinations of one or more related listed items.

[0062] Other embodiments of the application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. The application is intended to cover any variations, uses or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice in the art to which the application pertains.

[0063] It should be understood that the present application is not limited to the precise construction that has been described and shown in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application.

Claims

1. A safety adjustment method for DC charging piles considering battery characteristics, characterized in that, The method includes the following steps: Obtain daily load data of the power grid in the area where the DC charging pile is located, as well as the charging duration and BCL messages of each charging vehicle connected to the DC charging pile at each time. Based on the similarity of the load data of the DC charging pile in the same time period before the same time on the same day and the previous day, and the difference between the dispersion of all load data before the same time on the same day and the previous day, and combined with the total charging power borne by the DC charging pile at the same time on the same day, the adjustable coefficient of the DC charging pile at each time on the same day is obtained. Based on the charging duration of each vehicle connected to the DC charging pile at each time of the day and the corresponding BCL message, the charging duration coefficient of each vehicle at each time of the day is obtained. Combined with the time interval between each time of the previous day and the first load peak thereafter, as well as the load data at each time of the day and the difference between it and the first load peak thereafter at the same time of the previous day, the safety adjustment compensation coefficient of the DC charging pile at each time of the day is obtained. Combined with the adjustable coefficient at each time, the safety adjustment coefficient of the DC charging pile at each time of the day is obtained. Then, it is determined whether the DC charging pile can safely adjust the charging parameters of the vehicles at each time of the day.

2. The DC charging pile safety adjustment method considering battery characteristics as described in claim 1, characterized in that, The formula for calculating the adjustability coefficient of the DC charging pile at different times of the day is as follows: In the formula, Let be the adjustable coefficient of the DC charging pile at the i-th time of the day. Let be the cosine similarity between the sub-load sequences at time i of the current day and the previous day. , Let be the ranges of all grid load data up to the i-th time point on the current day and the previous day, respectively. This represents the total charging power demand borne by the DC charging pile at the i-th moment of the day.

3. The DC charging pile safety adjustment method considering battery characteristics as described in claim 2, characterized in that, The sub-load sequence at each time point refers to the sequence of load data of a preset time length prior to each time point, arranged in chronological order.

4. The DC charging pile safety adjustment method considering battery characteristics as described in claim 2, characterized in that, The process of obtaining the total charging power demand of a DC charging pile at each time is as follows: obtain the voltage and current demands in the BCL messages of all charging vehicles connected to the DC charging pile at each time; multiply the voltage and current demands of each charging vehicle at each time as the charging power of each charging vehicle; and sum the charging power of all charging vehicles at each time as the total charging power demand of the DC charging pile at each time.

5. The DC charging pile safety adjustment method considering battery characteristics as described in claim 1, characterized in that, The process for obtaining the charging time coefficient of each vehicle charging at each time of day using the DC charging pile is as follows: when the charging mode field in the BCL message of each vehicle charging at each time of day using the DC charging pile is 010B, the charging time coefficient is the reciprocal of the charging time of each vehicle charging at each time of day using the DC charging pile; when the charging mode field in the BCL message of each vehicle charging at each time of day using the DC charging pile is 001B, the charging time coefficient is the charging time of each vehicle charging at each time of day using the DC charging pile.

6. The DC charging pile safety adjustment method considering battery characteristics as described in claim 1, characterized in that, The formula for calculating the safety adjustment compensation coefficient of the DC charging pile at various times of the day is as follows: In the formula, Let be the safety adjustment compensation coefficient of the DC charging pile at the i-th moment of the day. It is the absolute difference between the sampling time corresponding to the i-th time of the previous day and the first load peak thereafter. Let U be the charging time coefficient of the u-th vehicle at the i-th time of the day using a DC charging pile, where U is the total number of vehicles charging at the i-th time of the day using the DC charging pile. This refers to the grid load data at the i-th time point of the day. Let be the first load peak data after the i-th time point of the previous day, and exp() be an exponential function with the natural constant e as the base. This is a preset constant.

7. The DC charging pile safety adjustment method considering battery characteristics as described in claim 1, characterized in that, The safety adjustment coefficient of the DC charging pile at each time of the day refers to the normalized result of the product of the adjustable coefficient and the safety adjustment compensation coefficient of the DC charging pile at each time of the day.

8. The DC charging pile safety adjustment method considering battery characteristics as described in claim 1, characterized in that, The specific process for determining whether a DC charging pile can safely adjust the charging parameters of a vehicle at any time of the day is as follows: when the safety adjustment coefficient of the DC charging pile at any time of the day is greater than or equal to a preset threshold, it is determined that the DC charging pile can safely adjust the charging parameters of the vehicle at that time; otherwise, it is determined that the DC charging pile cannot safely adjust the charging parameters of the vehicle at that time.

9. A safety adjustment device for a DC charging pile considering the characteristics of a storage battery, characterized in that, The DC charging pile safety adjustment method considering battery characteristics as described in any one of claims 1-8, wherein the DC charging pile safety adjustment device comprises: The data acquisition module is used to acquire the daily load data of the power grid in the area where the DC charging pile is located, the charging time of each charging vehicle connected to the DC charging pile, and the BCL message of each charging vehicle at each time. The adjustment and analysis module is used to obtain the adjustment coefficient of the DC charging pile at different times of the day based on the regularity of the daily load data of the DC charging pile and the charging power it bears. The safety adjustment judgment module is used to obtain the safety adjustment coefficient of the DC charging pile at each time of the day based on the charging time of each charging vehicle connected to the DC charging pile, the adjustable coefficient at each time of the day, and the time interval and load difference between the same time of the previous day and the first peak load period thereafter, and then to determine whether the DC charging pile can safely adjust the charging parameters of the charging vehicles.

10. A DC charging pile safety regulation system considering battery characteristics, comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the DC charging pile safety adjustment method that takes into account the characteristics of the battery as described in any one of claims 1-8.

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