Bidirectional flyback DC-DC converter for hybrid electric vehicle: Utility, working and PSPICE computer model

There is a trend in the automotive industry to replace more engine driven mechanical and hydraulic loads with electrical loads, due to higher efficiency, safety requirement and driver's comfort. All of these new functions require the application of power electronics, by making use of dc/dc (conventional low power loads), dc/ac (air conditioning systems) and ac/dc (battery charging) converters. This paper first introduces the advance power system for hybrid electric vehicles (HEVs). The role of bidirectional dc-dc converter in the architecture is, then, explained. Out of several bidirectional dc-dc converter, flyback configuration is selected as it provides isolation between high voltage and low voltage side. Its working is also explained. Finally, a PSPICE model of the converter is proposed and results obtained for forward and backward conduction are reported.