Study On High-power On-board DC/DC Converter For Fuel Cell Electric Vehicles

Because energy, environmental protection and other issues become more prominent, fuel cell electric vehicles in recent years with the rapid development of a new car; 21st Century is the most promising green car cleaning. Fuel cell electric car uses fuel cells to replace the traditional gasoline as energy. However, the fuel cell output characteristic is weak, and its dynamic performance is unsatisfactory, which makes it don't adapt to a single-handed power source for vehicles. So usually outfit an accessorial energy sources with the fuel cell composed the power system together. Because the two energy sources have different rating of voltage, they need matching and transform using DC/DC converter. This dissertation discusses the DC/DC converter design applied in fuel cell electric vehicles, analyzes the circuit topology and designs the hardware and software. The main work of this dissertation is as follows:First, the fuel cell electric vehicles pose a matching energy-hybrid system structure is analyzed in detail. The electrical system component of the fuel cell electric vehicle is discussed, and the structure and function of various components are introduced. Based on this, the fuel cell electric vehicles on-board high-power DC/DC converter features and design requirements are introduced in a big way.According to the fuel cell output characteristics and the design requirements, ZVT-BOOST circuit is chosen as DC/DC converter circuit, after comparing the isolation and non-isolation different solutions. And the principle of the circuit topology is analyzedAs TMS320LF2407A DSP core controller, the hardware circuit is designed. The main circuit parameters are set, all system peripherals and IGBT module drive circuit are designed. Combined with TMS320LF2407A DSP hardware resources, software of fuel cell electric vehicles on-board high-power DC/DC converter control system is designed.Basic principle of SMVSC control is introduced; mathematical model of a fuel cell electric vehicle on-board DC/DC converter are designed. Based on the analysis of the model, SMVSC control plan of DC/DC is presented. Simulation of control systems is finished using MATLAB, Simulation results show the accuracy of theoretical analysis and calculation.In this paper, the DC/DC converter is accordance with characteristic of the fuel cell, which is effective in improving fuel cell efficiency and has a higher application value.