Tap changer monitor apparatus and method

摘要

A monitor is provided for use with an AC voltage regulator having a number of taps including a neutral tap and a tap changer capable of activating any of the taps. The voltage regulator receives an input voltage and produces an output voltage and is constructed so that the output voltage bears a relationship to the input voltage that depends on the activated tap. The tap changer is constructed to activate different taps as necessary to maintain the output voltage close to a target level despite fluctuations of the input voltage or load. The monitor apparatus includes a switch responsive to activation of the neutral tap for providing initial activated-tap information and a dead-reckoning computation device responsive to changes of the activated tap for updating the activated-tap information in accordance with changes of the activated tap made after the activation of the reference tap.