| Auxiliary system of electric locomotives is an important part of electric locomotives. With the fast development of power electronics and other techniques, it is the inevitable trend that the traditional phase-splitter would be replaced by the auxiliary convertor as the power supply for auxiliary system in electric locomotives. PWM rectifier designed in this dissertation is an AC/ DC part of the auxiliary convertor. It has the advantages of high input power factor and low pollution to power supply.PWM rectifier includes two kinds: voltage type and current type. This dissertation introduces their topologies and the general control strategy of PWM rectifier. Still, this dissertation mainly recommends work principle of single phase voltage type PWM rectifier, analyses and simulates related waveforms in bipolar and monopolar modulation so that easily make out the advantages of monopolar modulation. At the same time this dissertation also deduce models for single voltage PWM rectifier.This dissertation analyses the switch tube's choice of the main circuit and the reason of unbalanced current which occurs in paralleling switch tube and summarize the measures of switch tube applied in parallel connection, deduces the choice of inductance and proves the results through emulation, and gains a new method of calculating supporting capacitor of single voltage PWM rectifier and proves the capability of through simulation.This dissertation makes hardware designs of the system of electric locomotives, and has some results for controlling soft system.Initial, this dissertation is main to the directed current control of the single voltage PWM rectifier. We can see in the picture, the transient current control has good behave when the current is big, so it is used to more particular emulate, we can see from the pictures, it have good performance. And this dissertation use sliding mode control to emulate, it has higher requirement to secondary pulsant wave.
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