AC harmonic filter design methodology for HVDC systems

Abstract

The HVDC CIGRE benchmark network and published literature thereon discloses the use of harmonic filters and parameter values are given for the components. The methodologies on how to design the filters used is not disclosed. The focus of this paper is to identify the types of AC harmonic filters applied and to develop design methodologies for the CIGRE filter used. At both the converter stations, a combination of a 2nd order high-pass damped filter and a CIGRE C-type filter is identified. Methodologies were developed for these filters. The developed methodologies were compared and evaluated to ascertain discrepancies in filter components and results that arose due to the CIGRE using a non generalised C-type filter. The methodologies were adapted to accommodate these changes, and the results then became the same. The filter performances were evaluated in terms of the individual and total harmonic distortion indices and frequency sweeps. The filter design methodology was shown to be effective and can serve as a benchmark.