Buck型变换器非奇异固定时间滑模控制

Non-singular fixed time sliding mode control of Buck converters

摘要:

针对存在参数不确定性的Buck变换器系统,提出一种非奇异固定时间滑模控制方法。首先,设计非奇异固定时间滑模面,并基于该滑模面设计固定时间控制器,保证系统输出电压误差在固定时间内收敛到平衡点的邻域内,且其收敛时间上界与系统初始状态无关。其次,设计自适应律估计系统不确定干扰上界,有效抑制不确定干扰对系统的影响,该方法无需干扰上界的先验知识。最后,仿真结果验证了所提方法的有效性。

Abstract:

In this paper, a non-singular fixed-time sliding mode control method is proposed for buck converters with parametric uncertainties. Firstly, the non-singular fixed-time sliding surface is designed, and a fixed time controller is investigated based on the sliding surface to ensure that the system output voltage error converges to the neighborhood near the equilibrium point in a fixed time, and the upper bound of convergence time is independent of system initial states. Then, the upper bound of the disturbance is estimated by an adaptive law to suppress the influence of the uncertainties on the system, and the estimation method does not need the prior knowledge of the upper bound. Finally, the effectiveness of the proposed method is verified by simulation results.