Characterizing the double firing method for three-phase thyristor phase controlled converters

The recently proposed double firing method reduces the harmonic distortion and the reactive power generation in three-phase thyristor phase controlled converters. In this paper, this double firing method is characterized by using the generalized current source converter model and the space vector transformation. It is shown that the double firing method is the one which makes the zero vectors in which the output voltage and the input currents are all zero by intervening firings in every 1/6 period. The amounts of harmonic distortion and reactive power generation of the double firing method are compared with those of the conventional firing method. The operation of the double firing method is illustrated by an experiment