A Variable DC Link Voltage in On-board Battery Chargers for Electric Vehicle Charging Application

摘要

The two-stage on-board battery chargers in electric vehicles consists of conventional boost power factor correction (PFC) stage and an isolated DC-DC converter stage. Conventionally, the DC link voltage at output of PFC converter in the on-board chargers is maintained at 400 V which limits the charger output voltage in a range of 36-48 V, 72-150 V and 200-450V based on selection of DC-DC converter. The proposed variable DC link voltage at output of PFC converter enables wide output voltage range of charger with same DC-DC converter. The conventional boost PFC converters has the limitation that the required output voltage to be always greater than the peak of the input voltage. This paper presents a non-inverting two-switch buck-boost power factor correction (PFC) converter for use in on-board battery chargers to provide a wide DC link voltage. The operating modes of the converter in output voltage less than the peak of the input voltage and greater than peak of input voltage are explained in detail. The topology also maintains high power quality in both the modes. A 1kW PFC converter with universal input voltage 85-265 V(rms) is simulated in PSIM (11.0) and the preliminary experimental results is also been presented in the paper.