Pre-insertion Resistors in High Voltage Capacitor Bank Switching

Abstract: The switching of high-voltage capacitor banks for reactive-power or voltage support can produce significant transients. It is well understood that reactors, pre-insertion resistors, pre-insertion inductors, and synchronous switching can mitigate the transients. Circuit inductance can limit peak currents but resistance damps the oscillations most effectively. Computer simulations of transient inrush for single and back-to-back capacitor banks indicate that pre-insertion resistors can significantly reduce transients. The ability to incorporate another circuit parameter, the pre-insertion resistor, provides opportunities for improved high-voltage capacitor bank design.