A novel structure of multi-level high voltage source inverter

The authors deal with a new multi-level high voltage source inverter with GTO thyristors. A multi-level approach seems to be best suited for implementing high voltage conversion system because it leads to harmonic reduction and deals with safely high power conversion system independent of the dynamic switching characteristics of each power semiconductor device. However, a conventional multi-level inverter has some problems; voltage unbalance between DC-link capacitors and overvoltages across the inner switching devices. Therefore, they propose a novel structure of a multi-level inverter improving these problems