| 摘要 |
PROBLEM TO BE SOLVED: To provide a power supply unit which can minimize input current strain and fluctuation in current supplied to a load. SOLUTION: An AC power source AC is full-wave-rectified by a rectifying circuit RE, and the output of the rectifying circuit RE is converted into high-frequency output by an inverter circuit IVN and supplied to a load L. The inverter circuit INV is provided with a pair of switching elements Q1 , Q2 alternately turned on and off, an impedance circuit Z between the rectifying circuit RE and the switching elements Q1 , Q2 , a resonance circuit A where a serial circuit to the impedance circuit Z is connected between both ends of the switching element Q1 to take out the output to the load L, and a smoothing capacitor C0 . In the inverter circuit INV, a circuit constant is set, so that the effective value IA of current running through the resonance circuit A may be at least twice as much as the peak value of input current to the rectifying circuit RE from the AC power source AC. |
