This paper presents a method of state estimation for uncertain nonlinear systems described by multiple models approach. The uncertainties, supposed as norm bounded type, are caused by some parameters' variations of t...This paper presents a method of state estimation for uncertain nonlinear systems described by multiple models approach. The uncertainties, supposed as norm bounded type, are caused by some parameters' variations of the nonlinear system. Linear matri~ inequalities (LMIs) have been established in order to ensure the stability conditions of the multiple observer which lead to determine the estimation gains. A sliding mode gain has been added in order to compensate the uncertainties. Numerical simulations through a state space model of a real process have been realized to show the robustness of the synthesized observer.展开更多
Adaptive control of servo actuator with nonlinear friction compensation is addressed. LuGre dynamic friction model is adopted to characterize the nonlinear friction and a new kind of slid ing mode observer is designe...Adaptive control of servo actuator with nonlinear friction compensation is addressed. LuGre dynamic friction model is adopted to characterize the nonlinear friction and a new kind of slid ing mode observer is designed to estimate the internal immeasurable state of LuGre model. Based on the estimated friction state, adaptive laws are designed to identify the unknown model parameters and the external disturbances, and the system stability and asymptotic trajectory tracking perform ance are guaranteed by Lyapunov function. The position tracking performance is verified by the ex perimental results.展开更多
为提高无刷直流电机(brushless DC motor,BLDCM)转矩观测结果的准确性,定量分析了传统的反电势滑模观测器(sliding-mode observer,SMO)及相应的转矩观测结果受定子电感参数偏差的影响程度。分析表明,电感参数偏差会在定子电流变化时引...为提高无刷直流电机(brushless DC motor,BLDCM)转矩观测结果的准确性,定量分析了传统的反电势滑模观测器(sliding-mode observer,SMO)及相应的转矩观测结果受定子电感参数偏差的影响程度。分析表明,电感参数偏差会在定子电流变化时引起反电势和转矩观测误差。为消除这一影响,利用李雅普诺夫(Lyapunov)稳定性理论,设计了定子电感自适应辨识率,在线辨识得到电感参数,实时调整SMO的系数矩阵和输入矩阵,构成了新型的自适应滑模观测器,提高了观测精度。最后利用RT-LAB实时控制器进行实验,验证了理论分析的正确性。实验结果表明,所提方法能有效辨识出BLDCM的定子电感值,并正确观测出电机转矩。展开更多
文摘This paper presents a method of state estimation for uncertain nonlinear systems described by multiple models approach. The uncertainties, supposed as norm bounded type, are caused by some parameters' variations of the nonlinear system. Linear matri~ inequalities (LMIs) have been established in order to ensure the stability conditions of the multiple observer which lead to determine the estimation gains. A sliding mode gain has been added in order to compensate the uncertainties. Numerical simulations through a state space model of a real process have been realized to show the robustness of the synthesized observer.
基金Supported by State Key Laboratory of Explosion Science and Technology(QNKT11-08)
文摘Adaptive control of servo actuator with nonlinear friction compensation is addressed. LuGre dynamic friction model is adopted to characterize the nonlinear friction and a new kind of slid ing mode observer is designed to estimate the internal immeasurable state of LuGre model. Based on the estimated friction state, adaptive laws are designed to identify the unknown model parameters and the external disturbances, and the system stability and asymptotic trajectory tracking perform ance are guaranteed by Lyapunov function. The position tracking performance is verified by the ex perimental results.
文摘为提高无刷直流电机(brushless DC motor,BLDCM)转矩观测结果的准确性,定量分析了传统的反电势滑模观测器(sliding-mode observer,SMO)及相应的转矩观测结果受定子电感参数偏差的影响程度。分析表明,电感参数偏差会在定子电流变化时引起反电势和转矩观测误差。为消除这一影响,利用李雅普诺夫(Lyapunov)稳定性理论,设计了定子电感自适应辨识率,在线辨识得到电感参数,实时调整SMO的系数矩阵和输入矩阵,构成了新型的自适应滑模观测器,提高了观测精度。最后利用RT-LAB实时控制器进行实验,验证了理论分析的正确性。实验结果表明,所提方法能有效辨识出BLDCM的定子电感值,并正确观测出电机转矩。