145-kV Current Limiting Device - Field Tests

A 145-kV single-pole prototype fault- current-limiting device (CLD) was evaluated with a series of field tests at the Ohio Power Company´s Muskingum River plant. Laboratory and field tests were also made to evaluate the characteristics and design of the nonlinear resistor. Field tests of the CLD show that a prospective symmetrical fault current of 5.2 kA crest was limited to 3.7 kA instantaneous at the time the resistor was inserted and to 1.6 kA crest after insertion. The measured time from fault inception to resistor insertion was 1.6 ms.