摘要
针对一类输入受限的非线性离散时间系统,设计二阶段自适应控制器.根据先验知识,确定参数空间,在q个未知参数组成的参数空间的边界处建立q+1个自适应模型,将q+1个模型根据自适应系数组合为虚拟模型.基于虚拟模型,通过backstepping方法,设计控制器,采用高斯误差函数近似非对称饱和特性并给出了收敛性证明,得到系统的信号为半全局一致最终有界.最后进行数值仿真,相比于传统自适应控制,该模型能够更快地逼近真实参数,在执行器非对称饱和特性下能够加快系统的响应速度,减小暂态误差,最终的稳态误差收敛于一个较小的紧集,并且对船舶航向控制系统进行了仿真,取得了良好的控制效果.
A second level adaptive controller is designed for a class of nonlinear discrete-time systems subject to input asymmetric saturation. Gauss error function is used to approximate the asymmetric saturation characteristics of actuators.According to the prior knowledge, the parameter space is determined, q+1 adaptive models are built at the boundary of the parameter space composed of q unknown parameters. According to the adaptive coefficient, the q+1 models are combined into a virtual model. Based on the virtual model, the controller is designed by backstepping method, and the stability proof is given. It is proved that under this controller, the signals of the system can be guaranteed to be semi-globally uniform and ultimately bounded. Finally, numerical simulation is carried out. Compared with the traditional adaptive control, the model can approach the real parameters more quickly. Under the asymmetric saturation of actuators, the response speed of the system can be accelerated, the transient error can be reduced, and the final steady-state error converges to a smaller compact set. The ship course control system is simulated and achieved good control effect.
作者
吴伟
王昕
王振雷
WU Wei;WANG Xin;WANG Zhen-lei(Key Laboratory of Advanced Control and Optimization for Chemical Processes,East China University of Science and Technology,Shanghai 200237,China;Electrical and Electronic Experimental Teaching Center,School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《控制理论与应用》
EI
CAS
CSCD
北大核心
2020年第5期1166-1177,共12页
Control Theory & Applications
基金
国家自然科学基金项目(61673268,61890933,61590922,61703164)
国家杰出青年科学基金项目(61725301)
中央高校基本科研业务费专项资金项目资助.
关键词
多模型
离散非线性
二阶段自适应
非对称饱和
暂态性能
multiple models
discrete nonlinear systems
second level adaptation
asymmetric saturation actuators
transient performance
