Research about the power consumption detection technology of charger considering the harmonic and unbalanced current

In this paper, an electric vehicle charging posts(charger) power consumption detection technology based on harmonic wave and preventing leakage circuit breaker current imbalance technology is proposed. Firstly, for the working characteristics of electric vehicle charging posts, by studying harmonic characteristics produced by electric car charging posts, this paper analyzes harmonic effects on power measurement. And based on the Fast Fourier Transform (FFT) principle, the harmonic energy measurement method of car charging posts is studied. Since each phase current of charging post imbalance, to prevent the sum of each phase current vector of charging posts over the protection current threshold and the charging post breaker misusing in power circuit, preventing leakage circuit breaker current imbalance system is designed. Finally, this paper studies the power consumption detection methods of electric vehicle charging posts, and designs charging post power metering device.