Scope


IEC-1000-2-1 defines interharmonics as follows:
"Between the harmonics of the power frequency voltage and current, further frequencies can be observed which are not an integer of the fundamental. They can appear as discrete frequencies or as a wide-band spectrum."

IEEE 519 indirectly addresses inter-harmonics by discussing cyclo-converters which are one of the primary sources of inter-harmonics on power systems. IEEE 519 does not however, provide any general technical description of the phenomena, methods of measurement, or guidelines for limits. As the sophistication of power electronic interfaces to the power system increases, the frequencies present in the supply current are less likely to be limited to harmonics of the fundamental.
The task force will work to develop a paper that summarizes existing work on inter-harmonics, presents new research by task force members, and develop suggestions on how interharmonics should be addressed in IEEE 519.

Specifically, the following items regarding inter-harmonics will be discussed:

The task force will build on the existing terms and definitions of inter-harmonics found in IEC 1000-2-1 and 1000-2-2 and work in conjunction with other international standards organizations and technical committees. Specifically, close coordination will be maintained with the joint CIGRE/CIRED task force on Voltage Quality (CC02 - CIGRE 36.05).

It is expected that the body of work developed by the task force will be applied to the next revision of IEEE 519.

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Last updated July 14, 1999 by Erich W. Gunther