Buck型變換器的輸入電壓全補償前饋控制

摘要：為消除由輸入電源擾動引起的輸出電壓工頻紋波，改善DC/DC變換器動態性能，根據平均變量建模思想，為電壓型PWM控制的Buck型變換器，建立連續導電工作模式（CCM）下統一的平均變量等效電路，分析等效電路并根據不變性原理提出輸入電壓全補償前饋控制原理及實現方法。采用該方法的Buck型變換器可完全補償輸入電壓擾動，其輸出電壓對輸入電壓擾動具備動態不變性。仿真研究結果驗證了本文前饋控制原理及實現方法的正確性。 敘詞：平均變量 不變性原理 前饋控制 全補償 動態不變性 Abstract：To improve the dynamic performance of DC/DC converter against input voltage disturbance, and eliminate the low frequency ripple of output voltage, a uniform average equivalent circuit is established for buck series converters under voltage mode PWM control and in continuous conduction mode. According to the invariance principle and the equivalent circuit analysis, fully compensated input voltage feedforward control method and its implementation is presented. The buck series converter using this control method can fully compensate for the input voltage disturbance deviation, and achieve the dynamic invariance of output voltage against the input disturbance. Simulation results verify the correctness of the fully compensated input voltage feedforward control method and its implementation. Keyword：Average variable, Invariance principle, Feedforward control, Full compensation, Dynamic invariance