A New High Output Frequency Multilevel Inverter Topology of Traction Converter for Superspeed Maglev Train

Superspeed maglev train can achieve a theoretical speed from 1,000 to 4,000 kilometers per hour, which has potential application prospects in transportation, satellite launching and manned space flight in the future. Superspeed maglev train has high acceleration and large back EMF. The running speed of the maglev train is directly proportional to the output frequency of the traction converter. The traction converter is required to output high voltage, large current and high frequency. The control strategy of cascade topology combined with parallel technology can increase the voltage and current of traction converter. Due to the low switching frequency of large-power high-voltage electronic semiconductor devices, the maximum output frequency of the converter is limited. A new high output frequency multilevel inverter topology of traction converter for superspeed maglev train is proposed in this paper. Based on the basic unit of active neutral point clamped H-bridge, the topology has the advantages of frequency-multiplier output, high voltage, large power and balanced loss distribution.