| 摘要 |
PROBLEM TO BE SOLVED: To suppress the rush current and control the harmonic distortion, by providing a full-wave rectifier, an inductor for chopper, an ON/OFF control circuit of a switching element, a smoothing capacitor, and a load circuit in which the AC power supply such as the commercial power supply system as an input, and feeding the high frequency power to the load circuit. SOLUTION: A control circuit performs the zero-voltage detection of a switching element Q1, and outputs the ON drive signal for the prescribed period. The switching element Q1 is turned on by the H-output of an inverting circuit IC3 by closing a power supply AC, the output of the inverting circuit IC3 is inverted to L by charging a capacitor C9 by the control power supply Ccc, and the switching element Q1 is turned off. An inverter circuit (main circuit) is actuated in four modes according to the condition of the switching elements Q1, Q2 by the starting signal. Because the peak of the output current IDB of a full-wave rectifier DB is proportional to the output voltage VDB, the harmonic component can be cut if an inductor LO and a capacitor CO are selected optimum, and the power factor of the device can be improved. |
