| 摘要 |
A method and circuit for correcting a power factor in an alternating current/direct current power transformer. The circuit has an inductor fed by a rectified AC voltage, and a switch by which the inductor can be charged and discharged by closing and opening the switch, and further has a diode by which the discharge current of the inductor is fed to the output of the circuit. During the discharge phase, a voltage corresponding to the output voltage is measured, and the measured values are stored. It is further determined when the discharge current reaches or crosses the zero line at the end of a discharge phase. Switch-on and switch-off signals for actuating the switch are generated by analyzing the information determined. The switch should not be switched on again until a particular minimum switch-off time has been reached. |
