Research Of DC/DC Converter Used In The Fuel Cell Power Generation System

Fuel cell is an efficient and environmentally friendly energy source that can be used to solve the world's two difficulties of energy saving and environment protecting. As an important part of fuel cell power generation system, DC/DC converter affects a lot to the volume, weight, cost, efficiency and performance of the system. So, how to consider about these factors and design out suitable DC/DC converter becomes very important. At the same time, it helps a lot to bring the fuel cell to market use.This paper introduces the fundamental and characteristic of the fuel cell, analyzes the necessity and detail scheme of adding assistant energy sources to the fuel cell power generation system. Considering for the special demand of the fuel cell power generation system, this paper gives out a Push Pull Forward Converter (PPFC) with passive and lossless dual CDD snubber circuit. The principle of operation, the selection of snubber circuit, the design of the coupling inductor and the relationship between the DC/DC and DC/AC converters are illustrated and verified on a 1KW experimental circuit.A two-stage DC/DC converter consists of a boost and PPFC is presented in this paper through further research. The control strategy and the way of filter design are discussed. This two-stage converter keeps the advantages of the single-stage PPFC scheme and improves its several disadvantages. The simulation and experimental results verify the superiority of the two-stage converter scheme and prove out that it is suitable for the fuel cell power generation system.