Design of Multi-level Frequency Converter Based on Cells Series

Aiming at the existing problems of high-voltage frequency converter,the paper designed a new type of frequency converter,introduced hardware composition,working principle,circuit design and implementation method of software control of power unit of the frequency converter in details.The(frequency) converter(adopted) multilevel technology with cells series,which could obtain stepped SPWM waveforms,and could drive ordinary motor directly with no output filter.