开关电感Boost变换器的失效机理及基于参数扰动的混沌控制方案研究

开关电感Boost变换器是新能源系统中应用较为广泛的一种高增益DC-DC变换器。由于变换器本身的特性,当电路参数的变化超出一定范围时,会发生分岔、混沌等非线性现象,造成变换器失效,此时变换器无法正常稳定运行并且工作性能下降,因此有必要控制变换器从混沌态重回稳定态。基于参数扰动混沌控制法的基本原理,设计了适用于峰值电流控制型开关电感Boost变换器的混沌控制方案。该方案可使工作于混沌状态的变换器能迅速返回周期-1态稳定工作,其输出电压增益得以提高、输出纹波显著降低,并且在输入和负载有较大扰动时变换器系统均能稳定工作。利用非线性理论对变换器失效机理进行分析和混沌控制,对于DC-DC变换器参数设计、稳定性分析和性能提升具有一定的实际应用价值。

Study on Failure Mechanism of Switched-inductor Boost Converter and Chaos Control Scheme Based on Parameter-perturbation

Switched-inductor Boost converter has been widely used in the new energy systems. Whereas its complex nonlinear dynamic behaviors, such as bifurcation and chaos, have led to the failure of converter. Therefore, it is necessary to control the converter to stable state from chaotic state. In this paper, a new chaotic control scheme based on parameter-perturbation method is proposed and applied to a peak current-mode controlled switched-inductor Boost converter. And the converter operating in chaotic state can be controlled quickly to the period-1 orbit with better performances, such as higher voltage-gain and lower output ripples. In addition, the system can work stably when the input or load resistance has large disturbance, which means that the new scheme has better stability against input voltage or load resistance disturbance. The analysis of failure mechanism and chaos control based on the nonlinear characteristics of the converter can be helpful for the design of circuits'' parameters and the performance improvement.