Variable Zero Voltage Switching (ZVS) Hybrid Controller for Power Factor Corrector (PFC)

摘要

A power factor corrector (PFC), such as for an on-board charger (OBC) for charging a vehicle traction battery, uses an input voltage and an input current from a power source to output a desired voltage. The PFC has an inductor and first and second power switches. A micro-controller generates, for each half-cycle of the input voltage, first and second reference signals respectively indicative of (i) a sinusoidal envelope of the inductor current for which the PFC will absorb sufficient power from the power source for the PFC to output the desired voltage and (ii) a reverse value of the inductor current for which zero voltage switching (ZVS) of the switches is ensured. A comparator assembly turns the first switch off (on) and the second switch on (off) upon the inductor current equaling the outer sinusoidal amplitude envelope (the reverse value) whereby the PFC outputs the desired voltage with ZVS.