| With the rapid consumption of oil resources, pure electric vehicle draws wide attention. As the pure electric bus and its station in Shanghai World Expo reliably operate for 6 months, the pure electric vehicle has been accepted by the people. Its industry has great prospects for development. The lithium-ion battery has the advantages of high energy density, large number of cycle times and pollution-free. It is the preferred power source for the majority of pure electric vehicle. However, the domestic technology of power battery test equipment which is used to test battery performance and simulate actual working conditions is far behind foreign countries. High capacity power battery test equipment and its technology are completely monopolized by foreign brands.Therefore, a 100kW test equipment is presented in this paper to meet the requirements of performance testing of power lithium-ion battery packs used in pure electric vehicles. The equipment is composed of a three-phase PWM rectifier and a four-quadrant DC-DC converter. Two kinds of mathematical model of three-phase PWM rectifier are built in this paper. According to the model, main circuit parameters are calculated and optimum solution is selected. The DC-DC converter uses the dual four-quadrant DC-DC converter circuit topology to achieve higher output power and wider range of DC voltage. The hardware and software of PWM rectifier control system based on DSP56F803 is designed. A new control strategy is used to suppress the high bus voltage spike during the rapid transition between charging and discharging. The system closed-loop simulation model based on Matlab/Simulink is established also. A prototype of test equipment is completed. In the case of half load charging, the efficiency of prototype is 94.3%, its power factor is 100% and its THD is 8.1%. They satisfy the design requirements.
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