带恒功率负载多电平Boost变换器的复合非线性控制

针对带恒功率负载的多电平Boost变换器,提出一种将非线性干扰观测器和自适应滑模控制器相结合的复合非线性控制策略。首先应用精确反馈线性化方法将模型转化为布鲁诺夫斯基标准形式。然后在保证大信号稳定的前提下,将自适应控制方法和非线性干扰观测器加入到滑模控制器的设计中,利用李雅普诺夫理论证明整个闭环系统的稳定性。仿真和实验结果表明,与双闭环PI控制方法相比,该控制策略具有更好的动态调节性能和更强的鲁棒性。

COMPOUND NONLINEAR CONTROL OF MULTI-LEVEL BOOST CONVERTER WITH CONSTANT POWER LOAD

This paper proposes a composite nonlinear control strategy that combines a nonlinear disturbance observer and an adaptive sliding mode controller for a multilevel Boost converter with a constant power load. First, exact feedback linearization method is used to transform the model into Brunovsky’s canonical form. Then under the premise of ensuring the large signal stability of the system, the adaptive control method and the nonlinear disturbance observer are added to the design of the sliding mode controller, and the stability of the entire closed-loop system is proved by Lyapunov theory. Simulation and experimental results show that, compared with the dual closed-loop PI control method, this control strategy has better dynamic regulation performance and stronger robustness.