Deficiency of the IEC flicker meter for measuring interharmonic-caused voltage flickers

IEC flicker meter has been widely accepted as an international standard for flicker severity measurement. It is found, however, that the meter has a major deficiency: it is unable to measure flickers caused by interharmonics whose frequencies are higher than 102 Hz. Such interharmonics are not uncommon. Using field test results as an example, this paper demonstrates the deficiency of the flicker meter and analyzes the causes of the deficiency. The goal is to raise awareness on the problem and to promote research on improving the flicker meter algorithm.