新型混合单周BoostPFC变换器技术研究

Research on Novel One-cycle Control for Boost PFC Converter

研究了一种改进型单周期控制(OCC)算法在Boost功率因数校正(PFC)变换器中的应用。工作于连续导电模式(CCM)下的OCC PFC变换器具有控制电路简单、抗干扰能力强等优点,但二极管存在的反向恢复电流对过零点的输入电流影响较大,导致输入电流发生过零畸变,限制了功率因数的提高。为改善过零畸变,提高功率因数,采用一种工作于混合导电模式(HCM)下的改进型OCC技术,在CCM下,实时检测输入电流,当输入电流过零时,将变换器切换至断续导电模式(DCM),抑制了二极管的反向恢复问题,并将此改进型OCC技术应用于Boost PFC,搭建原理样机,通过实验验证了该新型控制策略的可靠性及理论分析的正确性。

An improved one-cycle control （OCC） algorithm for Boost power factor correction （PFC） converter is re- searched.0perates in continuous conduction mode （CCM） of OCC due to have a simple circuit,fast dynamic response, anti-interference ability and so on.However,the diode reverse recovery problems have a greater impact on the input current, so that the zero crossing of the input current distortion, which limits the power factor further improved.To overcome the above problems, using an improved OCC, which operates in a hybrid conduction mode （HCM）, converter still operates in CCM and detects the input current at the same time.When the input current is close to zero,switch the converter to discontinuous conduction mode（DCM）, very well avoid the diode reverse recovery problems.Improved OCC technology is applied into Boost PFC.A prototype is designed, the reliability and superiority of the novel control strategy are verified by experiments.