Active High Pass Filter for the Measurement of Supraharmonics

Abstract

There is a technical limitation to the measurement of supraharmonics (frequency disturbances between 2 - 150 kHz), where the amplitude of the supraharmonics relative to the 50 Hz fundamental component is too small for measurement instruments to be able to measure it. An active high pass filter was designed to enable accurate measurements of supraharmonics by attenuating the 50 Hz fundamental component and passing through the frequencies in the supraharmonic range. The filter enabled the measurement of a signal from an amplitude of 5 µV on top of a 325 V signal.