| 摘要 |
The invention relates to a method and circuit for correcting a power factor in an alternating current/direct current power transformer. The circuit has an inductor (L) fed by a rectified AC voltage (VIN), and a switch (S) by means of which the inductor (L) can be magnetized and demagnetized by closing and opening the switch, and further comprises a diode (D) by means of which the discharge current of the inductor (L) is fed to the output of the circuit. The following are directly or indirectly measured at a common measurement point (Pinsens) connected to a control unit (PFC): the voltage (Vout) at the output and the point in time at which the zero line of the discharge current of the inductor (L) is reached when the switch (S) is open; as well as the voltage (Vout) at the output and the current (ishunt) flowing through the switch (S) when the switch (S) is closed. |
