Selective Interharmonic Compensation to Improve Statcom Performance for Light Flicker Mitigation

Selective interharmonic compensation is introduced to improve Statcom performance for Light Flicker (LF) mitigation. The approach proposed modifies classical control algorithms based on the Park transform typically adopted for Statcom control. The improvement is obtained by introducing a selective interharmonic filter into the classical control scheme. This makes it possible to compensate only the interharmonics in a proper band around the fundamental frequency that mainly affects LF. The relevant effect is a reduction of the compensation power needed to obtain mitigations of LF emissions from the source to be compensated (e.g., arc furnaces) to levels compatible with standards. This makes it possible to reduce the Statcom sizing in the design stage or optimize the performances of existing Statcoms just by upgrading their control algorithms. Numerical and experimental case-studies confirmed the usefulness of the proposed LF mitigation strategy and provided a quantitative idea of the obtainable benefits.