Abstract: An apparatus and method for measuring the source-side line voltage from a source potential transformer (PT) of a regulator during reverse power flow. A reverse power regulation algorithm is employed during reverse power operation of the tapchanger to energize a contact relay which switches the analog voltage input from the load side to the source side of the regulator. Voltage regulation then operates based on the measured source side voltage instead of the traditional calculation of the source side voltage based upon the load-side voltage and regulator type.

Abstract: An apparatus and method for measuring the source-side line voltage from a source potential transformer (PT) of a regulator during reverse power flow. A reverse power regulation algorithm (“Source Side PT”) is employed during reverse power operation of the tapchanger to energize a contact relay which switches the analog voltage input from the load side to the source side of the regulator. Voltage regulation then operates based on the measured source side voltage instead of the traditional calculation of the source side voltage based upon the load-side voltage and regulator type.

Abstract: A microcontroller-based tap-changer controller including apparatus for keeping track of an electrically closed tap position and for automatically changing the tap setting of load tap-changing transformers and regulators; the tap-changer controller further utilizes the "keep-track" tap position to calculate the source voltage of the regulator for reverse power operations; and, a method for paralleling tap-changing transformers and regulators utilizing the circulating current of the units.