Multistep Resistor Control of Switching Surges

For system voltages above 500 kV the conventional one-step resistor cannot limit switching surge overvoltages to the desired level of 1.7 per unit or less. This paper presents the results of an analog computer study of four possible methods of controlling switching surge overvoltages with a breaker and/or resistors. The alternatives studied include synchronous control of closing without a resistor, a ganged three-resistor breaker, a ganged two-resistor breaker, and a controlled closing two-resistor breaker. Overvoltage limits and breaker timing criteria are obtained for each alternative.