Simulation Research of Traction Converter Based on MMC

摘要

Due to the high output voltage fluctuation and harmonics of the CRH3 traction converter, the further study of the topology and control strategy is made. The simulation model of traction converter based on the MMC topology is presented according to the main circuit parameters of CRH3 inverter. With the model, the input and output characteristics of the traction converter on the basis of the carrier phase-shifted modulation control and balance control of capacitor voltage are analyzed. The simulation results show that the optimized model based on the MMC topology gains a better performance compared to the traditional circuit. The output current and voltage are much more similar to a sine wave with lower harmonics, and the dc-link voltage fluctuation is smaller. In a word, the expected result has been achieved.