Evaluation of 13kV dry-type shunt reactor protection following near-miss

At the end of a bird-caused fault sequence, the protection scheme for a 13kV dry-type shunt reactor left the reactor energized and carrying load current on two phases, which resulted in a more severe fault when the field operator attempted to clear the shunt reactor using manually operated disconnect switches. The operator was not injured but given his proximity to the fault and arc, the result could have resulted in serious injury or much worse. In order to avoid such situations, this paper evaluates the protection scheme for 13kV dry-type shunt reactors, highlighting deficiencies, compares company practices against one industry guide, and describes planned improvements.