Patent ID: 8467202

Claim:
A flyback power system, comprising a rectifier and filter circuit, a pulse width modulation (PWM) controller, and a feedback circuit, the flyback power system further comprising: a master converter circuit, to convert power signals output from the rectifier and filter circuit into first direct current (DC) power signals to drive a load according to PWM signals of the PWM controller; a slave converter circuit, to convert the power signals output from the rectifier and filter circuit into second DC power signals according to the PWM signals of the PWM controller and to superpose the second DC power signals to the first DC power signals to drive the load if the load is heavy; and a slave converter control circuit, connected between the PWM controller and the slave converter circuit, and comprising: a first switch, comprising a control pole, a first pole, and a second pole, wherein the first pole is connected to the PWM controller, and the second pole is connected to the slave converter circuit; and a first switch control circuit, connected to the control pole of the first switch, to detect whether the load is heavy, and to turn on the first switch to control the PWM signals of the PWM controller to input into the slave converter circuit if the load is heavy, or to turn off the first switch to stop inputting the PWM signals of the PWM controller into the slave converter circuit.