类严格反馈系统的模糊弱扰动解耦控制

Fuzzy weak disturbance decoupling for strict feedback-like systems

大多数实际系统含有不确定项,且受到扰动的影响.采用模糊逻辑方法估计不确定项是降低不确定性影响的常见方法之一,而模糊近似扰动解耦是抑制扰动影响的主要手段.模糊近似扰动解耦对应的增益不等式包含无界项,所以无实际价值,为此提出模糊弱扰动解耦的控制方法.该方法采用模糊万能逼近定理估计不确定项,利用反步法设计控制器使得闭环系统具有弱扰动解耦性能,即闭环系统稳定且输出的范数不大于正常数加上扰动范数与正常数之积.仿真结果验证了模糊弱扰动解耦控制器能够保证闭环系统的弱扰动解耦性能.

All real control systems are affected by uncertainties and disturbances.It is common practice to estimate uncertainties by fuzzy logic systems.Fuzzy approximate disturbance decoupling is one of the methods to attenuate the impact of disturbances.The gain inequality of fuzzy approximate disturbance decoupling contains an infinite term,so it has no practical value.Thus,the concept of fuzzy weak disturbance decoupling is proposed.A fuzzy weak disturbance decoupling problem is to find a feedback controller so that the closed-loop system has weak disturbance decoupling performance,that is,the closed-loop system is stable and the norm of the output is not greater than the sum of a positive constant and the product of the norm of the disturbance and a positive constant.Finally,the effectiveness of the proposed method is verified through a numerical example.