THREE PHASE DIODE RECTIFIER FOR UNIT POWER FACTOR CONTROL

摘要

PURPOSE: A three phase diode rectifier for unit power factor control is provided to rectify the alternating current power to remove the harmonics and phase delay of the input current with respect to the input voltage. CONSTITUTION: The three phase diode rectifier comprises an input filter, boosting inductors, a power factor regulator, and an output filter. The three phase diode rectifier supplies the rectified two phase voltage(Vb) and current(Ib) to the load(Zl) by rectifying each phase of an input voltage(V1,V2,V3) by using three diode pairs(D11,D12,D21,D22,D31,D32). The input filter comprises three inductors(L1,L2,L3) and three capacitors(C1,C2,C3) to reduce the harmonic components of the input power. Each inductor is connected in series with each phase and each capacitor is connected between the adjacent phases. The boosting inductors(L1a,L2a,L3a) store energy when the boosting switch(Qb) is turned on and supply the stored energy to the load when the boosting switch is turned off. The power factor regulator is used to match the phase of the input current(I1,I2,I3) with the input voltage. The output filter having a diode(Db) and a capacitor(Cb) is connected in parallel with the load produces a complete direct-current voltage supplied to the load.