A high performance frequency insensitive quadrature phase shifter and its application in reactive power measurements

Abstract

Abstroct -This paper describes U high precision circuit for quadrature phase shifting in which frequenq controlled signal amplification is introduced so thut the umplitude of the phiuse shijited signal is not dependent on the frequency of the input signal. The implementation of the proposed quudrature phase shijiter is aimed at high accuracy reactive power memurements in AC power systems. The implementation of the new phase shijiter effectively reduces var/vcrrh measurements to watt/ivatthour measurenients. A prototype has been built and the test results are presented.