电动汽车充电纹波对直流电能计量影响分析

现有电动汽车直流充电桩的输出电压高、电流大且带有纹波,传统直流电能计量方式并未考虑大功率工作条件下纹波对其计量准确性的影响。为此,结合充电桩直流产生原理,根据直流充电机输出纹波特点和充电桩用直流电能表、直流电能计量模块的工作原理,重点研究和分析直流电能计量不同算法对带有纹波的高功率直流计量时存在的误差影响。分析了纹波影响规律,借助标准源和标准表进行验证,并在此基础上定量确定高功率状态下直流纹波对直流计量影响,为直流充电电能的准确计量、优化直流计量算法等提供依据。

Analysis of the influence of ripple on DC energy meter in EV charging

The DC charging pile of the existing electric vehicle (EV) has the characteristics of high output of voltage and current and both of them have ripple at the same time.The impact of ripple on the measurement accuracy was not taken into account in the traditional DC energy meter under high power working conditions.Based on the working principle of the charging pile,the characteristics of the output ripple of DC charging pile and the workirig principle of the DC energy meter or metering module,the errors of the different algorithms are analyzed in this paper.The regularity of ripple effects is analyzed,and a standard source and a standard DC meter are used to verify it.The error of the ripple on the DC energy measurement is determined quantitatively,and all about this research provides the basis for the accurate measurement of DC charging energy and the optimization of DC metering algorithms.