• Title/Summary/Keyword: controller design problem

Search Result 910, Processing Time 0.033 seconds

A study on computer-aided synthesis of process control system structure (전산기를 이용한 공정 제어구조 합성에 관한 연구)

  • Lo, Kyun;Yoon, En-Sup
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1987.10b
    • /
    • pp.670-673
    • /
    • 1987
  • The structure of chemical process has become increasingly complex, due to better management of energy and raw materials. As a consequence, the design of control systems for complete plants now constitutes the focal point of engineering interest, rather than controller designs for single processing units. Instead of traditional methods based on complex mathematical model, chemical processes are represented by structural array and cause-and-effect graph to apply non-numerical problem-solving techniques. A systematic logical procedure to synthesize alternatives of control system structure and some heuristic rules to select a feasible solution from the vast number of alternatives that are possible are considered in this study.

  • PDF

A Study on the Design of an Adaptive Controller with Variable Structure (가변 구조를 갖는 적응 제어기의 설계에 관한 연구)

  • Hong, Yeon-Chan;Choi, Jong-Hun
    • Journal of the Korean Institute of Telematics and Electronics B
    • /
    • v.33B no.1
    • /
    • pp.1-5
    • /
    • 1996
  • In the unification method of classical linear control and variable structure control, a problem that the error between the actual plant output and the nominal plant output exists consistently is solved by replacing the nominal plant with an adaptive observer. Since the exponentially convergent adaptive observer is used, the adaptive observer output converges to the actual plant output rapidly. So, the error does not exist after all and as a result the performance degradation of the control system is prevented.

  • PDF

A study on power system stabilization using Variable Structure Stabilizer (가변구조 안정화 장치를 사용한 전력계통 안정화에 관한 연구)

  • Chung, Jai-Kil;Kim, Jung-Ha;Kang, Dong-Gu
    • Proceedings of the KIEE Conference
    • /
    • 1995.11a
    • /
    • pp.83-85
    • /
    • 1995
  • A technique for power system' stabilization is presented using the variable structure control theory. The selection problem of the proper switching vector is very important subject for a design of the variable structure controller. In this paper, the switching vector is selected by desired eigenvalues allocation. and these desired eigenvalues are determined by eigenvalue assignment. Simulation results show that eigenvalue allocation variable structure stabilizer yields better dynamic performance than the others (conventional PSS, optimal linear stabilizer) and is robust to wide variations of the system parameters.

  • PDF

On Power System Frequency Control in Emergency Conditions

  • Bevrani, H.;Ledwich, G.;Ford, J. J.;Dong, Z.Y.
    • Journal of Electrical Engineering and Technology
    • /
    • v.3 no.4
    • /
    • pp.499-508
    • /
    • 2008
  • Frequency regulation in off-normal conditions has been an important problem in electric power system design/operation and is becoming much more significant today due to the increasing size, changing structure and complexity of interconnected power systems. Increasing economic pressures for power system efficiency and reliability have led to a requirement for maintaining power system frequency closer to nominal value. This paper presents a decentralized frequency control framework using a modified low-order frequency response model containing a proportional-integral(PI) controller. The proposed framework is suitable for near-normal and emergency operating conditions. An $H_{\infty}$ control technique is applied to achieve optimal PI parameters, and an analytic approach is used to analyse the system frequency response for wide area operating conditions. Time-domain simulations with a multi-area power system example show that the simulated results agree with those predicted analytically.

A Robust Disturbance Observer for Uncertain Linear Systmes (불확실한 성형시스템에 대한 강인 외란관측기)

  • Kim, Jun-Sik;O, Jun-Ho
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.20 no.9
    • /
    • pp.2731-2743
    • /
    • 1996
  • When modeling error is large of plant is time-varying, it is hard to obtain good robust performance and robust stability by conventional contorl methods. Here, we need to design a robust controller bearing modeling error. In this paper, based on recently developed Time Delay Control(TDC) and Disturbance Observer the output feedback Robust Disturbance Observer(RDO), which is easily combined with general linear control, is proposed. Proposed RDO is derived from extending the main idea of Disturbance Observer to multi-input multi-output linear system. RDO solves robust stability problem of Disturbance Observer and has the robust performance same as nominal performance. RDO controlled dual stage positioning system shows excellent robust performance.

Output Characteristic Analysis of High-Current Rectifier for Electrolysis of Seawater (해수 전기분해용 대전류 인버터 방식의 정류기 특성분석)

  • Cho, Won-Woo;Kim, Jin-Young;Kim, Seul-Gi;Kim, In-Dong;Nho, Eui-Cheol;Goh, Gang-Woo;Bae, Sang-Bum;Kang, Bu-Nyung
    • Proceedings of the KIPE Conference
    • /
    • 2010.07a
    • /
    • pp.570-571
    • /
    • 2010
  • To reduce the problem of ecocide, the plating equipment, water treatment system, electrolysis facility in ship need high current high power rectifier. This paper shows entire constitution of the proposed high-current rectifier for electrolysis of seawater, describes a way to design controller and analyzes output characteristic of the rectifier.

  • PDF

PThe Robust Control System Design using Intelligent Hybrid Self-Tuning Method (지능형 하이브리드 자기 동조 기법을 이용한 강건 제어기 설계)

  • 권혁창;하상형;서재용;조현찬;전홍태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
    • /
    • 2003.05a
    • /
    • pp.325-329
    • /
    • 2003
  • This paper discuss the method of the system's efficient control using a Intelligent hybrid algorithm in nonlinear dynamics systems. Existing neural network and genetic algorithm for the control of non-linear systems work well in static states. but it be not particularly good in changeable states and must re-learn for the control of the system in the changed state. This time spend a lot of time. For the solution of this problem we suggest the intelligent hybrid self-tuning controller. it includes neural network, genetic algorithm and immune system. it is based on neural network, and immune system and genetic algorithm are added against a changed factor. We will call a change factor an antigen. When an antigen broke out, immune system come into action and genetic algorithm search an antibody. So the system is controled more stably and rapidly. Moreover, The Genetic algorithm use the memory address of the immune bank as a genetic factor. So it brings an advantage which the realization of a hardware easy.

  • PDF

Local Stabilization of Input-Saturated Nonlinear Systems with Time-Delay via Fuzzy Control

  • Shin, Hyun-Seok;Park, Chul-Wan;Kim, Eun-Tai;Park, Min-Kee;Park, Mig-Non
    • International Journal of Fuzzy Logic and Intelligent Systems
    • /
    • v.2 no.3
    • /
    • pp.231-236
    • /
    • 2002
  • In this paper, we present an analysis and design method fur the control of input-saturated nonlinear systems with the time-delay. The target system is represented by Takagi-Sugeno (T-S) fuzzy model and the parallel distributed compensation (PDC) controller is designed to guarantee the local stability of the equilibrium point. We derive the sufficient condition for the local stability by applying Lyapunov-krasovskii theorem and this condition is converted into the LMI problem.

Stabilizable Predictiye Control with $H_{\infty}$ performance : The State-space approach ($H_{\infty}$ 성능을 가지는 안정화 예측제어 : 상태공간 접근법)

  • 정종남;조상현;전재완;박흥배
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2000.10a
    • /
    • pp.269-269
    • /
    • 2000
  • This paper presents a predictive control with H$_{\infty}$ suboptimal performance which is robust to disturbances and has a guaranteed stability. In order to derive the control law conveniently, state-space based approach, where the state variable is involved explicitly in the controller design and implementation is allowed. So an input-output model is converted to an equivalent observable canonical state-space form. The suggested control guarantees the norm bounded system output values from disturbances. A systematic way using the LMI method is presented to obtain appropriate parameters for Quadratic stability condition and optimization problem.

  • PDF

Robust Control of Disturbed Magnetic Bearing Rotor Systems (외란을 받는 자기베어링 주축계의 강건제어)

  • 강호식;송오섭
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.13 no.2
    • /
    • pp.40-46
    • /
    • 2004
  • Magnetic bearing has been adopted to support a rotor by electromagnetic force without mechanical contact and lubrication process. The recent growth of magnetic bearing applications in many industrial fields requires more accurate design of bearing-rotor system. Due to external forces and uncertainties of magnetic bearing system the actual performance and stability my be worse than it is designed. This paper describes the governing equations of rotor magnetic bearing systems and/or the designing of robust controller via standard $H_{\infty}$ control problem. The system stability and response characteristics are studied by simulations and verified with experimental results.