Papers by Keyword: Robust Control

Abstract: This paper was presented a new method to compute structured singular value μ, which had been used widely to analyze and synthesize robust controller with structured uncertainty. The formulated method was adaptive Newton pathfollowing to find an optimal singular path at some frequency for low-order function of μ-Δ(M). The objective of the new algorithm was to calculate structured singular value conveniently and stably and finally design a better robust controller.

Abstract: The disturbance observer is a specific method of designing a two degree of freedom control structure to achieve insensitivity to modeling error and disturbance rejection. It has been successfully applied in a variety of motion control applications. In motion control, the major sources of uncertainties are friction, inertia, and external disturbances. These uncertainties should be taken into account by any robust motion controller. In this paper, this element is a PD (proportional-derivative) controller. The disturbance observer proves its advantages through the simulation and experiments. With disturbance observer, better tracking performance can be achieved with less control energy.

Abstract: Stochastic systems with Markov jump is a new type of stochastic system in recent years, which is a new field integrated by information, control and Markov process. This paper introduces the research history and the newest research trends of stochastic systems with Markov jump, and presents many widespread theoretical and application problems. Moreover, some new research topics and directions related to stochastic systems with Markov jump are proposed.

Abstract: Network control system is a feedback control system of realizing the exchange of information control system in different regional components by using the digital communication. Focusing on the stability and robust control of stochastic network control system, this paper introduces the research history and the newest research trends, and presents many widespread theoretical and applications problems. Moreover, assumptions, main ideas, and conclusions of literature related to stochastic network control system are reviewed and commented.

Abstract: With the expending of power system and the complexity of system structure,operating stability, reliability and economy is faced with opportunities and new challenges.this paper, A hierarchical classification control structure is hired to finish coordinated control tasks based on multi-agent system,The simulation results show that decentralized coordinated control scheme is better than a simple decentralized robust control, decentralized coordinated control programs, especially in the case of large interference effect, Thus, the proposed scheme is effective to improve power systems transient stability and to enhance the robustness.

Abstract: Boiler is a complicated control object with multi-variable, strong coupling and uncertain time-delay. It is hard to get ideal control effect with normal controller. This paper presents the overview of advanced control techniques in traditional process control of boiler, such as PID multiplex control system, modern control system, intelligent control system, decoupling control system and robust control system. The future of advanced control research and application is also discussed.

Abstract: In recent years, electro hydraulic servo systems are more and more widely used in the aerospace, manufacturing industry and the agricultural machinery. As a result, higher requirements are put forward for the performance and application environment, including better tracking precision and respond speed. Aiming at the shortcomings of conventional PID controller, such as the large overshoot, long transfer time and poor robustness performance, a robust control scheme with dual-loop structure is proposed in this paper. Simulation results show that better performances are acquired in the novel approach in contrast with the PID control scheme and the structure of the proposed scheme is simple and easy to implement.

Abstract: This paper deals with the design and evaluation of robust excitation controller for a single-machine infinite-bus power system. The design of the regulator guarantees the stability of the closed loop system and ensures the output voltage is maintained within an acceptable threshold. In addition, it damps out local mode oscillations for small signal disturbances. The designed robust controller is also analyzed under change in step input and disturbance, which limits the heavy oscillations on the speed ω and voltage. Glover-McFarlane loop shaping algorithm is applied in designing the robust excitation controller. Two different techniques such as Optimal control and mixed sensitivity approach is used in this paper. The performance of the AVR was analyzed and compared with IEEE type2 Exciter.

Abstract: For the non-measurable states, a control of switched fuzzy systems is presented based on observer. Using switching technique and multiple Lyapunov function method, the fuzzy observer is built to ensure that for all allowable external disturbance the relevant closed-loop system is asymptotically stable. Moreover, switching strategy achieving system global asymptotic stability of the switched fuzzy system is given. In this model, a switching state feedback controller is presented. A simulation shows the feasibility and the effectiveness of the method.

Abstract: This paper presents an adaptive robust controller for discrete-time systems with time-varying uncertainty and time-varying delay. The controller is designed based on the online parameter estimation and robust H∞ approach. Simulation result is given to verify the effectiveness of the proposed controller.