IEC PAS 62544:2008 pdfダウンロード。Active filters in HVDC applications 1 ACTIVE DC FILTERS IN HVDC APPLICATIONS 1.1 INTRODUCING ACTIVE DC FILTERS The conversion process in an HVDC transmission system introduces harmonic currents into the DC transmission lines and the AC grid connected to the HVDC converters. These harmonic currents may cause interference in the adjacent systems, such as telecommunication equipment. The conventional solution to reduce the harmonics has been to install passive filters in HVDC converter stations [1] 1) . When the power line consists of cables, this filtering is normally not necessary. The development of power electronics devices and digital...