IGCT Self-Protection Strategy for IGCT Converters

The high-power semiconductor IGCT is widely used in two-level or three-level IGCT converters and for these converters a comprehensive system-protection strategy may be used to protect the IGCT. But there are still some problems resulted from signal transmission delays, such as incorrect timing, low response speeds, second breakdown and those problems can result in IGCT overload failure, bridge-arm shoot-through and other consequences. In this paper, the anode voltage and current parameters gained from the IGCT device are studied as protection reference in a new GCT gate drive unit. The gate drive unit can control and process the signal logic, and execute safe and reliable switching action. The signal is simultaneously feed back to the host computer in IGCT converters to perform the switching control of other devices. This new gate unit can effectively reduce device failure rates and improve the reliability of IGCT converters systems, while reducing operating costs.