Abstract:

PLC communication will be interfered by harmonics in the charging circuit for the electric vehicle based on the power line carrier, thus, affecting system stability. Regarding harmonic currents in three-phase four-wire uncontrollable rectifier and high-frequency power conversion, active and passive filters with the specified sub-harmonic control strategy can be adopted to change the n times of harmonics in the detected load current signal to DC value through the synchronous rotating reference frame. Current. And current PI control is conducted upon extracted by the low-pass filter to achieve the purpose of eliminating the specified harmonics. Both the theoretical analysis and simulation experiment showed that the method can effectively filter the current harmonics to ensure the sinusoidal characteristics of the current waveform, providing a theoretical reference for the upcoming PLC communication construction of the electric vehicle charging station.

Key words: power carrier, harmonic suppression, active power filter, selective harmonic, fuzzy PI control