Higher Frequency Emissions in the Range of 2 - 150 kHz (Supraharmonics) in Electricity Distribution Networks

There has been a steady growth of grid connected power electronic (PE) equipment over the last few decades. More recently this rate of growth has been quite notable related to both low power level (eg. domestic solar photovoltaic systems, electric vehicles chargers) and high power levels (eg. large solar and wind farms, voltage source converters in HVDC and MVDC applications). The associated concerns on harmonics injected by these installations have also grown at the same time. Over many years harmonic frequency range of interest has been limited up to 2 kHz, however, in the recent years this interest is seen to have extended to higher frequencies up to 150 kHz because of the above growth of grid connected PE equipment. In addition, power line carrier (PLC) communication systems associated with smart metering are also seen to be growing, especially in Europe, which inject narrow band signals having frequencies ranging from 3 kHz to around 500 kHz superimposed on the mains supply. There exists a significant wealth of knowledge and expertise related low frequencies up to 2 kHz associated with their emission, immunity and propagation in power systems. However, there is a compelling need to advance the knowledge related to frequencies beyond 2 kHz up to 150 kHz so that existing knowledge gaps can be filled facilitating the ongoing research and development efforts. This elevated frequency range is commonly associated with the nomenclature "supraharmonics" or simply higher frequencies (HF). Associated with supraharmonics, some of the key areas where new knowledge need to be developed are associated with their measurement, emission characteristics, impact on equipment life time, propagation in electricity networks, and device modelling in the frequency range of 2 - 150 kHz.