Design and control of a ultracapacitor boosted hybrid fuel cell vehicle

In this paper, an ultracapacitor boosted hybrid fuel cell vehicle drive train has been introduced, in which, fuel cell provides basic power and ultracapacitor provides peaking power to meet load demand. A unidirectional boost DC/DC converter couples the fuel cell to the DC bus, and a bidirectional buck/boost converter couples the ultracapacitor to the DC bus. The system parameters have been designed, which includes, traction motor power rating, fuel cell power and ultracapacitor energy capacity. A control strategy has been developed for controlling the fuel cell to operate in its high efficiency region and the ultracapacitor to deliver peaking power to meet the load demand. Simulation has been performed to verify drive train performance for full load acceleration and speed varying driving pattern.