A three-pulse model of DC side harmonic flow in HVDC systems

Abstract

A model for analysis of DC side harmonics in HVDC systems is proposed. The model includes the stray capacitances of converter transformers and bushings and represents the 12-pulse converter as four three-pulse harmonic voltage sources. The appearance of ground-mode triplen harmonics of troublesome magnitude in pole and electrode lines, as noted in recent site measurements, is explained, as is the increase in magnitude of the characteristic 12-pulse harmonics. The consequences for DC design and the specification of telephone interference criteria are also discussed.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>