Possible framework for EMC coordination of interharmonics in low voltage distribution networks

Electromagnetic compatibility (EMC) is an essential requirement for the disturbance free operation of equipment connected to electricity networks. To ensure a holistic overall approach to EMC, known interference mechanisms have to be protected by introducing indices for their proper quantification and by establishing suitable emission limits and immunity test levels that form the best possible trade-off of sharing costs, risks and responsibilities between all involved stakeholders (usually network operators and manufacturers). Recently, flicker in modern lamps caused by interharmonic distortion was identified as a new interference phenomenon which is not yet covered by the existing EMC coordination framework in IEC 61000 or IEEE. A new EMC coordination framework addressing this interference phenomenon is proposed in this paper and it is intended to serve as guidance for standardization committees to extend or update the relevant standards. The process for implementing EMC coordination is followed step-by-step in the proposed framework starting from characterizing the phenomena, then defining suitable indices and measurement methods to capture the phenomena, and finally proposing a set of limits.