Voltage, power and current ratings of series voltage controllers

The active power injection requirements are calculated for a series voltage controller (or DVR) under various system and load conditions, for different fault types, for three-phase load and for single-phase load. It is shown that the power requirement depends on the sag magnitude and phase-angle jump as well as on the power factor of the load. For controllers with an energy reservoir the voltage-tolerance curve of the load-controller combination is obtained. For a combined shunt-series controller the current rating of the shunt controller is found. Finally the voltage rating of the series controller is assessed