Design And Development Of DC Charger Test System

As a fast charging facility for electric vehicles,DC charger with the advantage of the faster charging efficiency than the AC charger enables the electric vehicles to be able to supplement the fuel in a shorter time like traditional cars.But as a metering device,its accuracy is closely related to the relationship between the owner of the electric vehicle and the power supply company.On the one hand,it is related to the vital interests of the owners of electric vehicles,and on the other hand,the quality control of the charger is related to the power supply company.Therefore,realizing the metrological verification of DC charger have great practical significances for the development of electric vehicles.First,analyzed the system structure,charging principle and charging method of the DC charger;studied the testing methods of the items in the metrology regulations and standards,discussed its shortcomings and designs the system for various testing methods based on the standard table method combined with the actual situation;designed the overall scheme and technical index of the test system.Secondly,completed the hardware design of the test system: designed a electric energy standard meter,verified the standard meter can fulfil system requirement from two aspects of accuracy and simulation,calculated the uncertainty of the standard meter;designed conforms to the standard and fulfil the current carrying capacity of the charging socket and a double charging plug cable;selected appropriate IPC with KVM switch as the control center of the test system;selected the standard 8U portable machine box and designs the internal structure of the test system chassis,the front and rear panels and the inner line of the power line;combined the main parts of the design into the hardware part of the whole test system.Then,completed the software design of the test system based on C#: analyzed and designed the overall requirements of the system software,and divided the software into three sub modules,user management,system test and device management;completed the user management sub module software,and realized login verification,authority control and information management functions combined with the basis of Access2013 database;designed the method of accurately accumulating the standard electric energy,the method of obtaining the actual electric energy and the time of the electric energy meter and the correct configuration of the load parameters,integrated the three methods into the data interaction module;designed four kinds of error test procedures,completed the project test module;designed the method of importing the system test results into the preset template,completed the print report module;the data interaction module,the project test module and the print report module were integrated into the system test sub module software,and the functions of the device management sub module software were designed to realize the parameters configuration,communication test and time calibration;designed the device management sub module software to realize the functions of parameter configuration,communication test and time calibration;the user management sub module,system test sub module and device management sub module are further integrated into the software design of the whole system.Finally,the accuracy of the test system was verified by experiment and simulation.The results showed that the accuracy of the test system can meet the requirements of the measuring device.The test system was used to measure the charger in the laboratory and draw the corresponding conclusion.