Research And Application Of Dual-core Energy Meter Based On Time-Synchronization For DC Charging Pile

Construction of electric vehicle charging facilities is an important guarantee for the development of new energy vehicle industry,and a vital measure to improve urban infrastructure,promote low-carbon development in cities and achieve electric energy substitution,it is of great significance for strategic transformation of national energy.DC fast charging,with the characteristics of speediness and efficiency,is gradually replacing AC slow charging.Therefore,DC metering will become an inevitable trend of its trade settlement.There are many problems with DC meters currently used in DC charging stations,such as the integration of software and hardware,partial interference between legal measurement and non-legal measurement.no support for remote upgrading and online detection,frequent occurrence of clock battery under voltage,limited extension,inability to meet the needs of the era of time-of-use electricity prices and grid big data,etc.Therefore,based on the requirements of IR46 international standard,this paper designs a DC dual-core smart meter based on GPS/BD system,which adopts the idea of independent metering core from management core,and modular design of each function,so that the legal measurement part and the non-legal measurement part do not interfere with each other.When the serial port time information of GPS/BD system is decoded with B code to calibrate the meter,the 1PPS generated by GPS/BD system is used to achieve accurate energy measurement.Finally,the electric energy data is stored in the memory in the form of an "absolute time+energy value".This design solution not only solves the problems of partial interference between the legal measurement and non-legal measurement,and clock under voltage,,but also supports remote upgrade and online detection,which has a good application prospect.This paper first introduces the research background and significance of DC meters.Based on the research status and trends of DC meters at home and abroad,the overall design scheme of DC dual-core meters is formulated.Then the key technology of time-synchronized DC dual-core meter is presented.The structure functional design of the dual-core meter is introduced in two parts:hardware and software.Finally,the basic error test,performance test and function test are conducted on the prototype according to the verification rules of the DC electric energy meter.The test results show that the DC dual-core meter designed in this paper meets the requirements of the regulations.