| 摘要 |
PURPOSE:To prevent the influence of ON and OFF of a semiconductor switch to the ripple output voltage by providing a controller for turning the switch of a converter ON and OFF at a period of 1/2 in synchronization with the oscillating frequency of an inverter. CONSTITUTION:A DC power source 1 is applied through a semiconductor switch 3 to an inverter 8. The primary winding 11 of an oscillation transformer 10 and a resonance capacitor 12 are connected to the inverter 8, semiconductor swtches 13, 14 are driven by a feedback winding 18, and biased via a resistor 19. A controller 20 controls the switch 3 ON and OFF, has a feedback winding 21, a sawtooth wave generator 22, a monostable multivibrator 23, a reference voltage power source 24, a comparator 25 and a semiconductor switch 26, etc., and turns the switch 3 ON and OFF at a period of 1/2 in synchronization with the ON and OFF period of the switches 13, 14. In this manner, the influence of the ripple due to the ON and OFF of the switch 3 can be almost eliminated, thereby reducing the value of a choke 17. |
