| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a control system of a power factor correction circuit that stabilizes oscillation operation and controls variation caused by variation in switching frequency, especially variation in the effective value of an AC power supply. <P>SOLUTION: A control circuit includes a voltage error amplifier 11 which amplifies the difference of the DC output voltage Vo and the DC output voltage command value Vref in order to control the boosted DC output voltage Vo to a fixed voltage, and generates a current command value Vi for controlling the input current Iin sinusoidally by operating the product of the output signal from the voltage error amplifier 11 and the detection voltage of the output voltage Vd from a rectification bridge 3 by using a multiplier 12. Furthermore, a comparator 13 which compares the magnitude of a voltage generated from a current detection resistor 9 for detecting the inductor current flowing through a switching element 6 with that of the output signal Vi from the multiplier 12, and an R-S FF circuit 14 which sets the off timing of the switching element 6 after the end of an off period set by a timer circuit 15 which sets the off period of the switching element 6 according to the voltage Vd are provided. <P>COPYRIGHT: (C)2010,JPO&INPIT |
