A new high power low loss GTO

A new high power, low loss, and low snubber gate turn-off thyristor (GTO) which has a current capacity of 6 kA with a snubber capacitance of 6 μF and blocking voltage of 6 kV has been developed. GTO has an advantage over conventional thyristors in its application to inverters. Recently GTO´s have been applied to high power inverters for traction and industries, and static V.A.R. Generators (SVG). The ratings of these GTO´s are such as 4.5 kV and 4 kA, or 6 kV and 3 to 4 kA by using a 4 inch silicon wafer. However, higher voltage, higher current GTO´s are required for the application of motor control for iron mills, and SVG´s for power supplies. On the other hand, reduction of power losses of GTO, and snubber capacitance were required for decreasing weight and volume and improving performance of equipment. For those reasons, a new high power, low loss, and low snubber GTO, FG6000AU-120D was developed. In order to develop this new GTO, we used some new technologies, and studied some parameters of device designs using some test samples. The development of this new GTO was based on the results of these studies and use of these new technologies. Design consideration of this GTO and electrical characteristics are described in this paper