Characterizing Voltage Fluctuations Caused by a Pair of Interharmonics

Voltage fluctuations and interharmonics have an inherent relationship. The magnitude of voltage waveform can fluctuate if it contains interharmonics. Although the impact of voltage fluctuation caused by a single interharmonic has been understood due to recent research activities, little knowledge is available on the impact of a pair of interharmonics. In reality interharmonics often appear in pairs. The objective of this paper is to investigate voltage fluctuations caused by a pair of interharmonics. Using rms and peak values as indices, the amount of voltage fluctuations caused by a pair of interharmonics is determined. Analytical formulas to estimate the impact are developed. One of the interesting findings of this work is that the voltage fluctuation impact of a pair of interharmonics can be equivalenced into that produced by one interharmonic component. This paper also presents potential applications of the findings.