POWER FACTOR CONTROL METHOD FOR THREE-PHASE CONVERTER, REACTIVE POWER CONTROL METHOD FOR THREE-PHASE CONVERTER, AND CONTROLLER FOR THREE-PHASE CONVERTER

摘要

PROBLEM TO BE SOLVED: To control reactive power by controlling a power factor of a three-phase converter to an optionally set power factor.SOLUTION: For power conversion of the three-phase converter in which a three-phase alternating current is PWM-converted to output a direct current, a controller for the three-phase converter calculates, on a three-phase AC input side of the three-phase converter, a symmetrical part voltage value of a three-phase balance system from a Y-phase voltage, sets a power factor on a DC output side of the three-phase converter, calculates an average active power value from an output voltage value and an output current value, and average reactive power from the set power factor, generates a compensation signal for compensating for an unbalanced voltage of the three-phase AC voltage and a control signal for controlling the power factor based upon the found symmetrical part voltage value, average active power, and average reactive power, and generates a control signal for outputting a direct current by PWM-converting the three-phase alternating current with the compensation signal and control signal.