Determination of harmonics in an ac power system caused by hvdc converters

HVDC converters are significant point sources of harmonic signals in a power system. As a result, converter filters are often required to reduce the levels of low audio frequency range harmonics injected into an AC network. The objective of this paper is to describe and demonstrate a harmonic power flow algorithm and digital computer program that can be used to analyze characteristic harmonics and solve for the truncated Fourier series of bus voltages and line currents in a balanced three phase system with multiple six and twelve pulse line commutated converters. Filter analysis and HVDC converter operation under a variety of bipolar and monopolar conditions are illustrated for an example transmission system. Results are compared to conventional analysis methods.