Flicker source identification by interharmonic power direction

Flicker is an important power quality index and is currently receiving increasing concern. The identification of the flicker source is necessary for the utility company to find who is the responsible for measured flicker, and so to act accordingly to improve power quality. Nevertheless, not much work has been done in this field. This paper analyzes the correlation between flicker and interharmonics, and proposes a novel method based on interharmonic power direction for flicker source identification. Simulations and field tests are provided for some typical flicker sources, such as an induction motor and a variable frequency drive (VFD). The results validate the effectiveness of the proposed method