Fast response GTO assisted novel tap changer

A new type of GTO thyristor assisted tap changer is outlined which addresse s the problems of traditional schemes, The scheme minimizes conduction loss es in the solid state devices and also permits a fast response speed throug h the adoption of fast actuator driven vacuum switches. This paper describe s a prototype tap changer for a low voltage 300 kVA transformer using the n ew method of tap changing. The prototype operates at current levels similar to those at which a full scale tap changer would work, Test results are pr esented.