CN-121998469-A - Super charging pile load characteristic evaluation method and system based on multidimensional index system

Abstract

The invention discloses a super charging pile load characteristic evaluation method and system based on a multidimensional index system, comprising the steps of obtaining original data of a charging station, constructing a daily charging coupling probability density function and daily charging frequency distribution in the week, and carrying out random simulation on arrival time of a vehicle; the method comprises the steps of obtaining a result obtained through random simulation and a charging power model of each stage, constructing an integral power demand curve, obtaining power data of a super charging station and a slow charging station through the integral power demand curve, preprocessing, calculating the preprocessed data through a double-layer evaluation system to obtain an index value, obtaining a load difference value between the super charging station and the slow charging station through the index value, and giving out a comprehensive evaluation result. A systematic quantitative evaluation system for the load characteristics of the super charging piles is established, quantitative comparison basis is provided for the load characteristic difference between the super charging stations and the slow charging stations, and scientific basis is provided for site selection of the charging stations and optimization of the distribution network.

Inventors

• ZHANG JIAXIN
• WEI XIANGYING
• QIU ZHIXIN
• YANG JIACHEN
• MA TIANYU

Assignees

• 海南电网有限责任公司海口供电局

Dates

Publication Date

20260508

Application Date

20251209

Claims (10)

1. 1. The super charging pile load characteristic evaluation method based on the multidimensional index system is characterized by comprising the steps of obtaining the original data of a super charging station and a slow charging station, and constructing a daily charging coupling probability density function and daily charging frequency distribution in the week; Carrying out random simulation on the arrival time of the vehicle by utilizing the intra-day charge coupling probability density function and the intra-week charge frequency distribution; constructing an overall power demand curve by utilizing a result obtained by random simulation and a charging power model of each stage; Obtaining power data of a super charging station and a slow charging station through the integral power demand curve, and preprocessing the power data; Calculating the preprocessed data by using a double-layer evaluation system based on the dispersion and time sequence difference characteristics to obtain an index value; and obtaining a load difference value between the super charging station and the slow charging station through the index value, and giving out a comprehensive evaluation result.
2. 2. The method for evaluating the load characteristics of the super-charging pile based on the multi-dimensional index system of claim 1, wherein the intra-day charging coupling probability density function is characterized in that a day is divided into a plurality of 15min time intervals, data of a charging station are mapped onto the time intervals according to the access time and the access time of an electric vehicle, frequencies occupied by different time intervals are calculated as intra-day coupling probability densities, and the intra-day coupling probability density is expressed as: Wherein, the Representing the probability density of the intra-day coupling, Representation of The number of vehicles accessing the charging pile at any time, Representing the total number of vehicles connected into the charging pile on the same day; the daily charge frequency distribution within the week is expressed as: Wherein, the The charging frequency of each day of the week is shown, Representation Zhou Nadi The number of the charged vehicles in the day, Indicating the total number of charged cars in a week.
3. 3. The method for evaluating the load characteristics of the super-charging pile based on the multidimensional index system as set forth in claim 2, wherein said random simulation comprises randomly sampling said time interval according to the intra-day coupling probability density after randomly extracting for one day according to the charging frequency of each day in the week to obtain the arrival time of each vehicle.
4. 4. The method for evaluating the load characteristics of the super-charging pile based on the multidimensional index system as set forth in claim 3, wherein the charging power model of each stage is constructed by simulating the power change characteristics of the electric vehicle in the actual charging process and introducing random disturbance items, and is expressed as: When (when) At this time, the precharge phase: When (when) At this time, the fast charge phase: When (when) At the same time, to complement the charging phase: When (when) At this time, for the trickle charge phase: Wherein, the Indicating time of day A difference from a time when the vehicle begins to charge; Representing a maximum charging power; 、 、 、 Respectively representing the duration of the precharge phase, the fast charge phase, the complement charge phase, and the trickle charge phase; 、 、 、 Respectively represent the difference value as The charging power of the stage; 、 、 、 the random disturbance term is subjected to normal distribution with the mean value of 0.
5. 5. The method for evaluating the load characteristics of the super-charging pile based on the multidimensional index system as set forth in claim 4, wherein the overall power demand curve is a result obtained through random simulation, and the power curves of all vehicles are overlapped in a staggered manner on a time axis according to the arrival time by combining the power change process of a single vehicle in each stage to obtain a total power curve changing along with time, wherein the total power curve is expressed as: Wherein, the Representing the overall power demand curve at time t, Indicating the charging power of the ith vehicle at time t, Indicating the arrival time of the ith vehicle.
6. 6. The method for evaluating the load characteristics of the super-charging pile based on the multi-dimensional index system as claimed in claim 5, wherein the double-layer evaluation system comprises a power discrete degree evaluation system and a time sequence power difference characteristic evaluation system which are respectively used for representing the spatial distribution characteristic and the time change characteristic of the charging load.
7. 7. The method for evaluating the load characteristics of the super-charging pile based on the multi-dimensional index system as set forth in claim 6, wherein the load difference value is obtained by using a differential quantitative evaluation formula, and the differential quantitative evaluation formula calculates the deviation degree of the super-charging station and the slow-charging station on each index by adopting a relative difference form, wherein the deviation degree is expressed as follows: Wherein, the Indicating that the super charging station is at the index The value of the above-mentioned value, Indicating that the slow charging station is at the index The value of the above-mentioned value, Representing the difference value.
8. 8. A super charging pile load characteristic evaluation system based on a multi-dimensional index system and a super charging pile load characteristic evaluation method based on the multi-dimensional index system are characterized by comprising a charging behavior modeling module, a difference analysis and comprehensive evaluation module, wherein the charging behavior modeling module is used for acquiring original data of a super charging station and a slow charging station, constructing a daily charging coupling probability density function and daily charging frequency distribution, using the daily charging coupling probability density function and the daily charging frequency distribution for random simulation of vehicle arrival time, using a result obtained by random simulation and a charging power model of each stage to construct an integral power demand curve, the multi-dimensional evaluation system construction module is used for obtaining power data of the super charging station and the slow charging station through the integral power demand curve and preprocessing, calculating the preprocessed data through a double-layer evaluation system based on a dispersion degree and a time sequence difference characteristic to obtain index value, and obtaining a load difference value between the super charging station and the slow charging station through the index value and giving a comprehensive evaluation result.
9. 9. The computer equipment comprises a memory and a processor, wherein the memory stores a computer program, and the computer program is characterized in that the processor realizes the steps of the multi-dimensional index system-based super charging pile load characteristic evaluation method according to any one of claims 1-7 when executing the computer program.
10. 10. A computer readable storage medium is provided, which is characterized in that the computer program is executed by a processor to realize the steps of the method for evaluating the load characteristics of the super-charging pile based on the multi-dimensional index system according to any one of claims 1 to 7.

Description

Super charging pile load characteristic evaluation method and system based on multidimensional index system Technical Field The invention relates to the technical field of electrical engineering and automation thereof, in particular to a method and a system for evaluating the load characteristics of a super charging pile based on a multidimensional index system. Background With the deep advancement of global energy transformation and sustainable development strategies, electric vehicles are undergoing rapid growth as an important representative of green traffic. Up to now, the global electric automobile has been over 2000 tens of thousands, with the chinese market being over 40% and exhibiting explosive growth. This trend has driven the rapid development of charging infrastructure, wherein super charging piles become key facilities for alleviating "mileage anxiety" of electric vehicles by virtue of high efficiency and high power. However, the charging load of an electric vehicle has a significant difference from the conventional load. The power of a single super charging pile is generally 60-350 kW, and is far higher than 7-22 kW of that of a common household charging pile. When a large number of electric vehicles are charged in a specific period, a significant impact is easily generated on the power distribution network. Researches show that when the permeability of the electric automobile is increased by 10% under the disordered charging condition, the peak load of the power distribution network can be increased by 15% -25%, so that the peak-valley difference of the power grid and the peak regulation pressure of the system are further increased. Such load concentration may not only lead to local grid overload, voltage deviations and reduced power quality, but also increase distribution equipment investment and operating costs. In the prior art, a multi-dimensional index evaluation system for the super charging pile is not formed, and a quantitative evaluation framework for combining load discreteness and time sequence fluctuation is lacking. Therefore, it is necessary to propose an innovative method capable of systematically characterizing the load of the super-charging pile and supporting multidimensional data analysis and differential evaluation, so as to realize precise modeling and evaluation of the charging load. Disclosure of Invention The method comprises the steps of establishing a systematic analysis and evaluation method for the specific load characteristics of the super-charging pile, establishing an evaluation index system, accurately describing the dynamic fluctuation characteristics of the load of the super-charging pile, and establishing a quantitative comparison method for the difference between the super-charging pile and the load characteristics. In order to solve the technical problems, the invention provides the following technical scheme: In a first aspect, the present invention provides a method for evaluating load characteristics of a super-charging pile based on a multidimensional index system, comprising: Acquiring original data of a super charging station and a slow charging station, and constructing a daily charging coupling probability density function and daily charging frequency distribution in the week; Carrying out random simulation on the arrival time of the vehicle by utilizing the intra-day charge coupling probability density function and the intra-week charge frequency distribution; constructing an overall power demand curve by utilizing a result obtained by random simulation and a charging power model of each stage; Obtaining power data of a super charging station and a slow charging station through the integral power demand curve, and preprocessing the power data; Calculating the preprocessed data by using a double-layer evaluation system based on the dispersion and time sequence difference characteristics to obtain an index value; and obtaining a load difference value between the super charging station and the slow charging station through the index value, and giving out a comprehensive evaluation result. The invention relates to a method for evaluating load characteristics of a super-charging pile based on a multidimensional index system, which comprises the following steps that a daily charging coupling probability density function is divided into a plurality of 15min time intervals, data of a charging station are mapped onto the time intervals according to the access time and the access time of an electric vehicle, frequencies occupied by different time intervals are calculated as daily coupling probability densities, and the daily coupling probability density functions are expressed as: Wherein, the Representing the probability density of the intra-day coupling,Representation ofThe number of vehicles accessing the charging pile at any time,Indicating the total number of vehicles accessing the charging stake on the same day. The daily charge frequency distributio