A fast active power filter to correct line voltage sags

Abstract

An active power filter for compensating voltage sags that occur on a weak AC power system is described. The proposed active power filter is especially suitable in situations where sensitive data processing and other critical loads are to be operated on a weak AC system. The proposed filter is fast acting and simple in design. A design procedure based on IEEE/ANSI voltage withstand tolerance (IEEE standard 446-1987) is proposed. Laboratory tests on a prototype filter show fast response and linear correction characteristics. >