Staged fault and laboratory tests on a cable pair protection system designed to serve power stations

Cable pairs entering power stations may be subjected to ground potential rise (GPR) and/or induction of several thousand volts during power system faults. A cable protection system designed to give a high degree of reliability is described, and the results of staged fault and laboratory tests are discussed. An analysis of neutralizing transformer transient performance shows how the transformer´s behavior during fault conditions is determined by its volt-time capability.