Boost变换器的双闭环分数阶PI控制研究

Control of boost converter by a double closed-loop fractional-order PI control method

为提高Boost变换器输出电压的控制性能和抗干扰性,提出一种电压环和电流环均采用分数阶比例积分(PI)控制器的双闭环控制方法.该方法在建立的双闭环分数阶PI控制系统数学模型基础上,结合控制系统频域设计理论设计出电流环、电压环的分数阶PI控制器参数,并利用Bode图分析了被控系统的稳定性和鲁棒性.Boost变换器的双闭环分数阶PI控制仿真结果表明,即使在电源电压、负载,以及期望输出电压的变化条件下,相比双闭环整数阶PI,以及电压环分数阶PI、电流环整数阶PI的两种控制情形,该方法能实现变换器具有更好的输出电压性能和控制鲁棒性.

A double closed-loop fractional-order PI control Strategy is proposed to improve control performances and robustness of Boost converter,in which voltage loop and current loop adopt fractional-order proportional-integral(PI)controller.From the established mathematical model of double closed-loop Fractional-order PI control Boost converter system,the fractional-order PI controller parameters of voltage loop and current loop are designed according to the frequency domain theory.The stability and the robustness of the controlled system are discussed by using Bode diagram.The simulation results of double closed-loop Fractional-order PI control demonstrate that under the variable condition of source voltage,load and desired output voltage,compared with the complete integral-order situation or single integral-order situation of double closed loops,the presented double closed-loop fractional-order PI control method can achieve better output voltage performance and robustness.