A Fuzzy Control Algorithm to Characteristic Harmonics of Converter In HVDC System

In practice, the ignition angel and extinction angel of a converter often deviate from the given value for various reasons. As is known, this situation tends to result in the increase of characteristic harmonic amplitudes in AC/DC side of the converter. As a result, this will do much harm to the devices of power systems and increase the power consumption. In this paper, the harmonic expressions of AC/DC side are linearized and the fuzzy control theory is adopted to form the control strategy to modify the ignition angel ¿ and extinction angel ¿ in order to decrease the 5th characteristic harmonics in rectifier side and the 6th in inverter side. The simulation results in two-generator system show that this method can actually control the characteristic harmonic amplitudes of current and voltage within a certain boundary.