A module based self-balanced series connection for IGBT

In order to meet the growing demand of electric energy, high-voltage dc transmission and flexible ac transmission has been actively investigated to improve the bulk power transmission efficiency. Due to the limitation of the voltage and power rating of a single device, series connection technology of semiconductor devices has been applied for high voltage and high power applications. In this paper, a new series connection method of self-commutating switches is proposed. The proposed method can realize self balancing among the switches with simple algorithm and reduced size and rating requirement. Experiments have verified the performance of the proposed method.