CIRCUIT FOR POWER FACTOR CORRECTION OF AC-DC POWER CONVERSION SYSTEM

摘要

The present invention relates to a power factor improvement control circuit using a switch mode power converter that periodically converts an on-off mode according to a switching frequency of a switching element to convert an AC power source into a DC power source, the sine wave having a magnitude proportional to the current of a reactor in the circuit. AC that improves the power factor by making the input current into a sine wave by using a periodically changing value such as the ripple current of the reactor by driving the switching element with a PWM waveform that is output by comparing the input waveform voltage with full-wave rectification of the input voltage. It relates to a power factor improvement control circuit of a DC power converter.;To this end, the present invention is a power factor improvement control circuit using a switch mode power converter for converting the on-off mode periodically according to the switching frequency of the switching element to convert the AC power source to the DC power source, the amplifier 10 to a constant level The voltage V (SH1) of the amplified detection shunt SH1 is input and reset by the reset circuit 12 at regular intervals, and its output is proportional to the value of I (L _out ), and the sawtooth wave V on the sine wave is proportional to the value of I (L _out ). The multiplier output waveform V obtained by sequentially integrating the circuit 11 and the multiplier 17 with the integrating circuit 11 generating the 10 and the waveform V1 obtained by full-wave rectification of the sawtooth wave V 10 and the input voltage. And a comparator 18 for generating a pulse width modulation (PWM) waveform for driving the switching element T1 by comparing (17).;AC, DC, Converter, Power Factor