高压直流输电(HVDC)系统的附加控制器可以提高系统的暂态稳定性。本文针对交直流输电系统,应用控制李雅普诺夫函数理论(Control Lyapunov Function Theory)设计了直流系统附加控制器,首先建立输电系统数学模型,同时建立计及网络拓扑的...高压直流输电(HVDC)系统的附加控制器可以提高系统的暂态稳定性。本文针对交直流输电系统,应用控制李雅普诺夫函数理论(Control Lyapunov Function Theory)设计了直流系统附加控制器,首先建立输电系统数学模型,同时建立计及网络拓扑的系统结构保持能量函数,然后根据控制李雅普诺夫理论推导出提高系统暂态稳定的直流附加控制律。与常规直流附加控制相比,该控制器能够有效提高系统的暂态稳定性,仿真结果验证了设计附加控制器的正确性和有效性。展开更多
This paper deals with the robust stabilization problem for a class of nonlinear systems with structural uncertainty. Based on robust control Lyapunov function, a sufficient and necessary condition for a function to be...This paper deals with the robust stabilization problem for a class of nonlinear systems with structural uncertainty. Based on robust control Lyapunov function, a sufficient and necessary condition for a function to be a robust control Lyapunov function is given. From this condition, simply sufficient condition for the robust stabilization （robust practical stabilization） is deduced. Moreover, if the equilibrium of the closed-loop system is unique, the existence of such a robust control Lyapunnv function will also imply robustly globally asymptotical stabilization. Then a continuous state feedback law can be constructed explicitly. The simulation shows the effectiveness of the method.展开更多
A nonlinear sliding mode adaptive controller for a thin-film diffractive imaging system is designed to achieve accurate pointing direction over the attitude of subarrays in large-diameter mirror arrays.The kinematics ...A nonlinear sliding mode adaptive controller for a thin-film diffractive imaging system is designed to achieve accurate pointing direction over the attitude of subarrays in large-diameter mirror arrays.The kinematics and dynamics equations based on error quaternion and angular velocity are derived,and a diffractive thin-film sub-mirror array controller is designed to point precisely.Moreover,the global stability of the controller is proved by the Lyapunov method.Since the controller can adaptively identify the inertia matrix of each sub-mirror system,it is robust to bounded disturbances and changes in inertia parameters.At the same time,the continuous arctangent function is introduced,which is effectively anti-chattering.The simulation results show that the designed controller can ensure the accurate tracking of the diffractive film in each sub-mirror in the presence of rotational inertia matrix uncertainty and various disturbances.展开更多
Based on a piecewise quadratic lyapunov function （PQLF）, this paper presents stochastic stability analysis and synthesis methods for ItO and discrete T-S fuzzy bilinear stochastic systems. Two improved stochastic st...Based on a piecewise quadratic lyapunov function （PQLF）, this paper presents stochastic stability analysis and synthesis methods for ItO and discrete T-S fuzzy bilinear stochastic systems. Two improved stochastic stability conditions have been established in terms of linear matrix inequalities （LMIs）. It is shown that the stability in the mean square for T-S fuzzy bilinear stochastic systems can be established if a PQLF can be constructed. Considering the established stability criterion, the controller can be designed by solving a set of （LMIs）, and the closed loop system is asymptotically stable in the mean square. Two illustrative examples are provided to demonstrate the effectiveness of the results proposed in this paper.展开更多
文摘高压直流输电(HVDC)系统的附加控制器可以提高系统的暂态稳定性。本文针对交直流输电系统,应用控制李雅普诺夫函数理论(Control Lyapunov Function Theory)设计了直流系统附加控制器,首先建立输电系统数学模型,同时建立计及网络拓扑的系统结构保持能量函数,然后根据控制李雅普诺夫理论推导出提高系统暂态稳定的直流附加控制律。与常规直流附加控制相比,该控制器能够有效提高系统的暂态稳定性,仿真结果验证了设计附加控制器的正确性和有效性。
基金Sponsored by the Natural Science Foundation of Zhejiang Province in China(Grant No. Y105141).
文摘This paper deals with the robust stabilization problem for a class of nonlinear systems with structural uncertainty. Based on robust control Lyapunov function, a sufficient and necessary condition for a function to be a robust control Lyapunov function is given. From this condition, simply sufficient condition for the robust stabilization （robust practical stabilization） is deduced. Moreover, if the equilibrium of the closed-loop system is unique, the existence of such a robust control Lyapunnv function will also imply robustly globally asymptotical stabilization. Then a continuous state feedback law can be constructed explicitly. The simulation shows the effectiveness of the method.
基金supported by the Central University Basic Research Fund of China(No.3072022CFJ0202)the Central University Basic Research Fund of China(No.3072022CFJ0204)。
文摘A nonlinear sliding mode adaptive controller for a thin-film diffractive imaging system is designed to achieve accurate pointing direction over the attitude of subarrays in large-diameter mirror arrays.The kinematics and dynamics equations based on error quaternion and angular velocity are derived,and a diffractive thin-film sub-mirror array controller is designed to point precisely.Moreover,the global stability of the controller is proved by the Lyapunov method.Since the controller can adaptively identify the inertia matrix of each sub-mirror system,it is robust to bounded disturbances and changes in inertia parameters.At the same time,the continuous arctangent function is introduced,which is effectively anti-chattering.The simulation results show that the designed controller can ensure the accurate tracking of the diffractive film in each sub-mirror in the presence of rotational inertia matrix uncertainty and various disturbances.
基金This work was supported in part by the National Natural Science Foundation of China under Grant 61304063, in part by the Fundamental Research Funds for the Central Universities under Grant 72103676, in part by the Science and Technology Research Foundation of Yanan under Grant 2013-KG16, in part by Yanan University under Grant YDBK2013-12, 2012SXTS07.
文摘Based on a piecewise quadratic lyapunov function （PQLF）, this paper presents stochastic stability analysis and synthesis methods for ItO and discrete T-S fuzzy bilinear stochastic systems. Two improved stochastic stability conditions have been established in terms of linear matrix inequalities （LMIs）. It is shown that the stability in the mean square for T-S fuzzy bilinear stochastic systems can be established if a PQLF can be constructed. Considering the established stability criterion, the controller can be designed by solving a set of （LMIs）, and the closed loop system is asymptotically stable in the mean square. Two illustrative examples are provided to demonstrate the effectiveness of the results proposed in this paper.
