DC transmission line excess voltage protection - comprises excess voltage eliminator across thyristor gate to protect rectifiers

摘要

A method for protecting rectifier for d. c. transmission lines from excess voltages, includes application of an excess voltage eliminator with series connected ballast resistor. The thyristor gate of the rectifier is allowed to be triggered once at the response-time point of the eliminator, and then the normal operation of the rectifier is re-established. This method of protecting transmission lines results in a reduction of the time during which the consumers power supply is interrupted in response to the eliminator action in preventing excess voltages.