VUJE - Ferroresonance Damping Device (FDD)

The device is designed to damp Ferroresonances, which arise mainly at switching off the voltage transformers. The device gradually increases the value of load resistance connected to secondary winding of the voltage transformers when ferroresonance arises. The device continuously monitors secondary voltage of the transformer. If a set value is exceeded, a small smoothly controllable resistor is connected to secondary winding of the transformer. The resistance rises continuously after each period of voltage until complete disconnection. The system logic serves for satisfactory ferroresonance damping.