Interharmonics are periodic distortions of the 60 Hz sine wave whose periods are not multiples of the fundamental.
Simple nonlinear loads, whose waveforms are distorted but the same distortion in each cycle, produce harmonic currents (and thus introduce harmonic voltage distortion).
Complex nonlinear loads, whose waveforms are distorted by differing distortion in each cycle, produce interharmonics – frequency components in between the 60Hz-spaced harmonic components.
Interharmonics present a challenge for PQ investigations, due to the complexity of the measurements and data presentation.
An overview of interharmonic recording and data analysis methods with the Revolution is detailed here, along with some recommendations for getting started and best practices for studying the data in ProVision.
This white paper includes: