基于未知输入观测器的不匹配干扰系统滑模控制

Unknown Input Observer based Sliding Mode Control for System with Mismatched Disturbance

摘要:

针对具有不匹配未知干扰的非线性系统，研究基于状态估计和未知输入重构的控制问题.在状态可测和未知干扰已知假设下，提出了一种新滑模控制器设计方法，以达到输出渐近稳定；通过设计一种未知输入观测器，对系统的时变未知输入进行重构；基于高增益滑模观测器对未知干扰的微分和系统的输出微分信息进行了有限时间内的精确估计；设计了一种新的基于观测器的控制策略，并论证其可行性.利用一个实际模型验证该控制器的有效性.

Abstract:

This paper considers a control approach for a nonlinear system with mismatched disturbances via the estimation of system states and unknown inputs reconstruction. First, under the assumptions that both states and unknown disturbance are measurable, a new sliding mode controller is proposed to stabilize the output of the system. Then, by designing a kind of unknown input observer (UIO), a time varying unknown inputs reconstruction method is established. Meanwhile a set of high gain sliding mode observers are considered to obtain the derivative information of system outputs and the unknown disturbance in finite time, which will be further used in reconstructing the disturbance and designing control strategy. Subsequently, a new observer based controller is developed and its feasibility is proved. At last, a simulation example to a real model is given to verify the effectiveness of the proposed controller.