The Harmonic Characteristics of HVDC System and Reduction

HVDC converter produces a large number of harmonics, and these harmonics impact the surrounding environment. So it is need to reduce them effectively. This paper describes the mechanism of harmonics, and analysis of the characteristic of the harmonics. According to the characteristic, it puts forward corresponding suppression measures. AC filter can absorb harmonic and reduce the harmonic at the connection point, so ac filter is an effective measure, in addition, it also takes into account the reactive power compensation need. Because of the simple structure, reliable operation and easy maintenance, ac filter has been widely used. This paper focuses on the traditional type of filter design method, and calculates the parameters of double-tuned filter which is used in the Gezhouba-Shanghai HVDC transmission project.