Single-, two-and three-phase operation of the EV charger based on four-wire Vienna rectifier and two isolated DC-DC converters

This paper presents a simulation and experimental study focused on the operation of the EV chargers based on a four-wire Vienna rectifier and two isolated DC-DC converters. A standard Vienna rectifier switching at low frequency can co-operate with a three-phase grid providing sinusoidal and balanced currents with help of DC-DC converters (“three-phase PFC”). The paper shows that the same system may be immune to grid faults as can continue operation without one of three phases. Moreover, it can be also supplied from the single-phase grid after a slight modification of the topology. All these operation modes are carefully analyzed and simulated in Saber. Finally, initial experiments of the laboratory model of 5 kVA charger are also shown to prove correct operation in three-and single-phase modes.