Flicker effect produced by harmonics modulation

This paper discusses the flicker effect caused by voltage harmonics modulation. Simple functions are used to show that harmonic components, despite satisfying the specific harmonic limits, may produce excessive flicker due to combined modulation. A computer simulation procedure, based on the IEC recommendation, is first validated and then used to calculate the instantaneous flicker sensation, resulting from different combinations of harmonics modulation. The simulation results are then confirmed in laboratory tests using a flickermeter to measure the flicker obtained for the same type of signals synthesized by a programmable function generator.