Harmonic characteristics analysis of PWM-based electric vehicle chargers considering control strategy

On the basis of the introduction to the topology of PWM-based electric vehicle (EV) chargers considering control strategy, a theoretical analysis of the harmonic generation mechanism is conducted. By establishing simulation models of the charger, the distribution order of characteristic harmonic generated by single charger is analyzed. Furthermore, the harmonic coupling characteristics of multiple chargers working simultaneously are also discussed. The simulation results show that the harmonics generated by single charger mainly consist of high frequency components, including a small amount of low frequency components. As for multiple chargers, with the increase of the number of the chargers and the charging power, each harmonic current ratio and the current total harmonic distortion both show a downward trend.