Three-phase AC voltage control circuit

摘要

In a three-phase AC voltage control circuit containing reverse parallel connections of a thyristor and a diode or reverse parallel connections of thyristors in at least two phases, each asymmetrical AC voltage obtained by applying a line voltage of the power source having 30 degrees of phase lead from that of the phase voltage of the power source in the phase containing the thyristor to each polarized delay circuit is used as the power source for a firing angle control circuit of the thyristor in the phase.