High voltage conversion DC-DC step up converter for fuel cell applications

Fuel cells are becoming one of the most prominent sources of renewable energy. The voltage level of these sources are not that much high, necessitating step up converters with large gain of voltage. Step up converters with large voltage gain are needed to interface the fuel cell system with power transmission and distribution networks. Conventional boost converter usually operates at maximal duty cycle to acquire large voltage conversion. Reverse recovery problems of power diodes, high conduction loss at power switches, electromagnetic interference, and increased ripple inductor current and output voltage arise due to the use of very large duty cycle of the switching signal. This paper demonstrates a dc-dc step up converter capable of providing very large voltage conversion operating at a very low duty cycle (i.e. duty cycle <; 0.5). What is more, this converter works on same control signal for all the switches which lessens the complicacies during operation. The steady-state theoretical analysis has been described in this paper and finally the potency has been verified by simulation results.