基于比例积分控制的电压反馈型Buck变换器分岔

在分段光滑模型的基础上,推导出基于比例积分(PI)控制的电压反馈型Buck变换器的光滑模型及离散迭代模型.证明了功率系统的混沌吸引子在负载线上运动,并受到占空比的控制,模型的流形围绕吸引子运动并出现1周期、2周期及混沌现象;推导出电压反馈型PI控制系统的输出电压与Buck变换器的输出电压成线性关系,在此基础上指出PI控制中的比例因子起主导作用;分析了系统的倍周期分岔、边界碰撞和混沌现象,并展示了变换器状态的转移过程.实验结果表明了理论建模分析和仿真的正确性.

Bifurcation of proportion-integration-based voltage-mode Buck converter

Based on the piecewise smooth model, the smooth model and the discrete iterative model of proportion-integration (PI)-based voltage-mode Buck converter are derived. In this paper, it is proved that the chaotic attractor moves on the load line and is controlled by duty cycle, and that the manifold of the model moves around the chaotic attractor accompanied by the occurrences of period 1, period 2 and chaos phenomenon. The linear relationship between output voltage of the PI-controller and output voltage of Buck converter is derived, and then reveals that the proportional factor is a dominant one in PI controller. The period-doubling bifurcation, border collision and chaos are analyzed, and the state transfer process is exhibited. Experimental results verify that the theoretical modeling analysis and the simulation are correct.