电流-单周控制Buck变换器设计

Design of Current and One-cycle Controlled Buck Converter

针对传统单周控制Buck变换器存在的抗负载扰动能力差、存在稳态误差等问题,提出一种电流-单周控制策略。通过将电感电流和二极管电压叠加作为积分输入,有效增强了变换器的抑制负载扰动能力,且有很高的输出精度。详细阐述了电流-单周控制Buck变换器的工作原理,用状态空间平均方法建立了电流-单周控制Buck变换器的小信号模型,在此基础上对电流-单周控制Buck变换器进行了频域设计。最后,对所设计的Buck变换器进行了实验验证,结果表明,电流-单周控制Buck变换器在负载发生跳变时具有极低的电压超调和跌落.输出纹波约50mV.证明了该控制方法的正确性、有效性。

In order to solve problems such as poor load disturbance capability and existence of steady state error of traditional one-cycle controlled （OCC） Buck converter, an current and one-cycle eontrol（COCC） strategy is proposed. In this method ,the inductor current and the diode voltage are superimposed as integral inputs, which effectively enhances the ability of restraining load disturbance and has high output precision.The operation of COCC controlled Buck converter is described,the small signal model of COCC controUed Buck converter is established by using the average method of the state space, and the frequency domain design of the COCC controlled Buck converter is carried out.Finally, experiments are implemented.Resuh shows that, current and one-cycle control in load jump has extremely low voltage overshoot and drop, output ripple voltage is about 50 mV.Experimental result proves the correctness and validity of this control method.