| 摘要 |
PURPOSE: To obtain a power supply in which the harmonic components are suppressed and the input power factor is enhanced by approximating the waveform of input current to sine wave and to relax stress of the components. CONSTITUTION: An AC power supply Vs is full-wave rectified through a rectifier DB and fed to an inverter circuit INV. The inverter circuit INV feeds high frequency power to a load circuit comprising an inductor L2 and a capacitor C3 for resonance and a discharge lamp La. One set of transistor Q1 and diode D1 , constituting the inverter circuit INV, also constitute a step-down chopper circuit along with an inductor L3 , a diode D5 , and a capacitor C4 . When the output voltage of the rectifier DB drops below the voltage across the capacitor C4 , power is fed from the capacitor C4 to the inverter circuit INV through the diode D4 . |
