Abstract
This paper proposes an improved 3-level GCT converter for large capacity adjustable speed drives. The main circuit topology of the 3-level converter is also well-known as a neutral-point-clamped convener. Realizing high efficiency, a regenerative voltage clamping circuit is newly applied. And introducing a transient junction temperature analysis of power devices, the maximum output capacity is ensured. These technologies can contribute to improvement of the 3-level GCT converter especially using 6kV/6kA GCTs.
