This work proposes a high efficiency DC-DC converter for hybrid electric vehicles (HEV's). A conventional vehicle adopts an alternator connected to a combustion engine mechanically for supplying 12V electrical loads such as lights and charging a 12V b...
This work proposes a high efficiency DC-DC converter for hybrid electric vehicles (HEV's). A conventional vehicle adopts an alternator connected to a combustion engine mechanically for supplying 12V electrical loads such as lights and charging a 12V battery. Whereas, a HEV utilizes a DC-DC converter instead of an alternator. The DC-DC converter converters a high voltage power in a main battery(Ni-MH) to a 12V power unidirectionally. It enables to supply 12V electric power even under the case that an engine stops when a vehicle is idle state, namely, the idle stop mode, and improve fuel efficiency by using a surplus energy regenerated in braking instances. This work develops a high efficiency DC-DC converter by optimizing an electric power circuit, parameters and a control circuit.