Patent ID: 9350252
Filing Date: 2016-05-24
CPC Classification: H02M

Claim Text:
1. A system controller for protecting a power conversion system, the system controller comprising: a protection component configured to receive a demagnetization signal generated based on at least information associated with a feedback signal of the power conversion system, process information associated with the demagnetization signal and a detected voltage generated based on the at least information associated with the feedback signal, and generate a protection signal based on at least information associated with the detected voltage and the demagnetization signal; and a driving component configured to receive the protection signal and output a driving signal to a switch configured to affect a primary current flowing through a primary winding of the power conversion system; wherein: wherein the protection component and the driving component are further configured to, if the detected voltage and the demagnetization signal satisfy one or more conditions, output the driving signal to cause the switch to open and remain open in order to protect the power conversion system; wherein the protection component and the driving component are further configured to, in response to at least the detected voltage and the demagnetization signal not satisfying the one or more conditions, output the driving signal as a modulation signal to turn on and turn off the switch within a switching period corresponding to a modulation frequency.