Overview and Classification of Interferences in the Frequency Range 2–150 kHz (Supraharmonics)

Electromagnetic Compatibility (EMC) issues in the frequency range between 2 kHz and 150 kHz, also known as supraharmonics, were limited for a long time to industrial applications. Due to the increasing amount of mass-market equipment operating with switching frequencies above 2 kHz, the importance of (non-intentional) supraharmonics emission in public low voltage networks increased considerable during the last decade. Parts of the frequency range are also used in many countries by narrowband Power Line Communication (PLC) for meter reading (intentional emission). Consequently interferences can occur not only between devices with non-intentional emission, but also between those devices and the narrowband PLC applications. An increasing number of reported disturbances related to the supraharmonic frequency range emphasize its growing importance. This paper provides a systematic classification of possible types of interference in the frequency range 2 kHz - 150 kHz and illustrates them be several example measurements performed in public low voltage networks. It provides some design recommendations for electronic equipment and indicates future research needs.