谷值V^2控制Boost变换器的精确建模与动力学分析

Precise modeling and dynamic characteristics of valley V^2 controlled Boost converter

建立了谷值V2控制Boost变换器的离散迭代映射模型,在此基础上得到了输入电压、输出电容及其等效串联电阻(equivalent series resistance,ESR)变化时的分岔图,推导了不动点处的雅可比矩阵,利用特征值和最大Lyapunov指数对系统进行了稳定性分析,并验证了分岔图的正确性.重点研究了输入电压和输出电容及其ESR对谷值V2控制Boost变换器的动力学特性的影响.研究结果表明,输入电压增大时,变换器从周期1态经历1次倍周期分岔和边界碰撞分岔进入混沌状态;输出电容及其ESR具有相同的分岔路由,随着输出电容及其ESR的逐渐减小,变换器具有从周期1态经历周期2态、周期4态、周期8态、逐渐演变到混沌态的动力学行为.最后,用仿真和实验结果验证了本文理论分析的正确性.

A discrete iterative map model of valley V2 controlled Boost converter is established, based on which the bifurcation diagrams are obtained with the variation of input voltage, output capacitance and its equivalent series resistance （ESR）. Jacobi matrix at a fixed point is also derived, and according to it, the converter stability is analyzed using characteristic values and maximum Lyapunov exponent, thus the correctness of bifurcation analysis is validated. The effect of input voltage, output capacitance and its ESR on the dynamic characteristics of valley V2 controlled Boost converter is mainly investigated. It is found that as the input voltage increases continuously, the valley V2 controlled Boost converter changes from continuous conduction mode （CCM） period-1 to CCM period-2 due to period-doubling bifurcation, and comes into CCM chaos due to border collision bifurcation. The converter has the same bifurcation routes at output capacitance and its ESR： with gradual reduction of output capacitance or its ESR, the valley V2 controlled Boost converter behaves the evolutive dynamic behavior from CCM period-1 to CCM period-2, CCM period-4, CCM period-8, and CCM chaos. Finally, the simulation and experimental circuits are set up, and the correctness of theoretical analysis is verified by simulation and experimental results.