High power electronic device measurements of four IGCTs (4.5 kV/4.0 kA) in series connection

In this paper, high power electronics device measurements of four IGCTs (4.5 kV/4.0 kA) in series connection are put forward, which are used to investigate IGCTs in high power circuits with or without using RC-snubbers, or at least operation with small snubbers. The series connection of IGCTs is commonly applied in the high power inverter field, where expensive and space-consuming snubbers are adopted, to overcome the problems of asymmetric distribution of the blocking voltage among the IGCTs. Reasons of an asymmetric distribution of the blocking voltage during and after IGCT´s turn off process are analyzed. The first phase of the experimental results are presented and discussed.