Abstract:

Fuel cells used in electric vehicles are equipped the characteristics of wide range of output voltage,low output voltage and large output current.The high gain boost converter to supply power to lower level equipment is needed.In order to reduce the volume and electric stress of the converter,a three-level Boost converter for electric vehicles was designed.By analyzing the working principle of three-level Boost converter,the mathematical model of controlling to output was established by using state space averaging method.According to the solution structure of model,the corresponding PI compensation network was designed in control circuit.The performance of PI compensation network in control system was analyzed.The accuracy and feasibility of the compensation network are verified by experiments.The established model also provides corresponding theoretical basis for analysis of other circuits,equipped with certain popularization value.

Key words: electric vehicles, fuel cells, state space averaging method, PI compensation