Power System Growth and Use of New Technologies in Japan

Inter-harmonics are defined as the spectrum components that have frequencies between two harmonics. This letter points out that these fractional-harmonic components are not always the result of actual inter-harmonic sources. The signal sampling window size and position for Fourier analysis, as well as the time-varying characteristic of the signals, can all be factors leading to the so-called inter-harmonic components. Case studies illustrate that the inter-harmonic definition can be misleading and needs to be improved.