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Information × Registration Number 0203U000214, 0100U002589 , R & D reports Title Interharmonics in industrial power supply systems popup.stage_title Head Zhezhelenko I.V., Registration Date 28-01-2003 Organization Pryazovskyi State Technical University popup.description2 The interharmonics in the industrial power supply system have been investigated. Interharmonics are harmonic fluctuations with frequencies not multiple of the supply network frequencies. Interharmonics are generated by the loads which operate continuously or during short periods in transient mode. This operation mode results from the variations in the load as part of the technological process or from peculiar features of the electromagnetic processes going on during the work of these devices, e.g. alternating work of the converter valves, etc. Transient processes which cause interharmonics are, as a rule, of a random character and can be referred to the category of stationary random processes. Interharmonics cause additional active power losses, accelerated insulation aging, power supply reliability reduction, etc. Presently it is absent common approach to normalization, methods of calculation and forecasting of interharmonics. Traditional filtering methods used for harmonic control are not sufficientif interharmonics are present due to their probabilistic nature. In this connection, the main subject of investigation is analysis, calculation, forecasting and mitigation techniques, which used probability methods spectral-correlation theory of random processes. The paper describes methods for estimating the levels of interharmonics by applying Fast Fourier Transform directly to a random process of the interharmonics source current and to its correlation function. The energy of the discrete current interharmonics spectrum of quickvariable loads has been calculated. The authors analyzed peculiar interharmonics spectrums of network current in the direct frequency converters - cycloconverters with a onephase outlet at different control function. Product Description popup.authors popup.nrat_date 2020-04-02 Close