Suppression of Temporary Overvoltages Caused by Transformer and AC Filter Inrush Currents at the Shin-Shinano Frequency Converter Station

The temporary overvoltage problem associated with ac-dc converter stations is caused by the converter transfornmer Mnagnetizing inrush currents. A damping resistor type suppressor is introduced into the AC filter of the Shin-Shinano Frequency Converter Station to supprets such overvoltages. A bonsiderable suppression effect is noted during the field testing, and the validity of the overvoltage prediction by calculation is also confirmed by the measurements.