开关电源恒功率控制的输入电压补偿方法

Voltage Compensation for Constant Power Control of Switching Mode Power Supply

对于工作于宽输入电压范围的离线式电流型控制开关电源,为了获得恒功率控制,需要加入输入电压补偿电路以平衡不同输入电压时的过功率保护点。分析了传统反激式开关电源的输入电压补偿原理,提出了一种低功耗的可控输入电压补偿方法,以降低开关电源的待机功耗。实验结果证明了该方法的可行性。

Voltage compensation is required for the constant power control of off-line switching mode power supply（SMPS） to balance the differences of over power protection point between high voltage and low voltage input.The principle of tradi-tional voltage compensation of fly-back converter is analyzed.A low loss controllable circuit for voltage compensation is proposed,which can reduce the stand-by power consumption of SMPS.The experimental results verify the feasibility of the proposed method.