A diode-clamped multilevel converter with reduced number of clamping diodes

This paper presents a diode-clamped multilevel converter topology with reduced number of clamping diodes. The novel topology uses a combination of multilevel converter cells with different number of levels. The proposed topology and its switching pattern are discussed based on a five-level converter, and it can be easily extended to N-level converter. Compared with the traditional topology, the proposed topology can significantly reduce the number of clamping diodes and the system cost of the multilevel converter. A detail comparison of the two topologies has been conducted. Simulation and experimental results show the validity of the topology.