• 제목/요약/키워드: closed-loop identification

검색결과 74건 처리시간 0.025초

아라고 원판 시스템의 상태공간 모델 식별 (State-Space Model Identification of Arago's Disk System)

  • 강호균;최수영;최군호;박기헌
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 하계학술대회 논문집 D
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    • pp.2687-2689
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    • 2000
  • In many cases the systems are so complex that it is not possible to obtain reasonable models using physical insight. Also a model based on physical insight contains a number of unknown parameters even if the structure is derived from physical laws. These problems can be solved by system identification. In this paper, Arago's disk system which has both stable and unstable regions is selected as an example for identification and a state-space model is identified using tailor-made model structure of this system. In stable region, a state-space model of Arago's disk system is identified through open loop experiment and a state-space model of unstable region is identified through closed loop experiment after using fuzzy controller to stabilize unstable system.

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퍼지추론을 이용한 파라미터 식별 및 D.C 서보 모터의 속도제어 (Parameter Identification with Fuzzy Inference and Speed Control of D.C Servo Motor)

  • 이은철;김종훈;이인희;남문현
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1995년도 하계학술대회 논문집 B
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    • pp.852-854
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    • 1995
  • This paper proposes a new identification method that utilizes fuzzy inference in parameter identification. The prosed system has an additional control loop where a real plant has replaced by a plant model. Fuzzy rules describe the relationship between comparison results of the features and magnitude of modification in the model parameter values. In this paper, the tuning method which determines parameters of PID controller automatically is described through applying this algorithm to DC servo motor. And we intend to investigate effectiveness of the method by experiments. This method is effective in auto-tuning because the response of the closed loop has verified. The simulated and the experimental results of the dc servo motor are shown to confirm the viability of this method.

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기준 모델 추종 기능을 이용한 뉴로-퍼지 적응 제어기 설계 (A design of neuro-fuzzy adaptive controller using a reference model following function)

  • 이영석;유동완;서보혁
    • 제어로봇시스템학회논문지
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    • 제4권2호
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    • pp.203-208
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    • 1998
  • This paper presents an adaptive fuzzy controller using an neural network and adaptation algorithm. Reference-model following neuro-fuzzy controller(RMFNFC) is invesgated in order to overcome the difficulty of rule selecting and defects of the membership function in the general fuzzy logic controller(FLC). RMFNFC is developed to tune various parameter of the fuzzy controller which is used for the discrete nonlinear system control. RMFNFC is trained with the identification information and control closed loop error. A closed loop error is used for design criteria of a fuzzy controller which characterizes and quantize the control performance required in the overall control system. A control system is trained up the controller with the variation of the system obtained from the identifier and closed loop error. Numerical examples are presented to control of the discrete nonlinear system. Simulation results show the effectiveness of the proposed controller.

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모델예측제어 기법을 이용한 제지공정에서의 지종교체 제어 (Control of Grade Change Operations in Paper Plants Using Model Predictive Control Method)

  • 김도훈;여영구;박시한;강홍
    • 펄프종이기술
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    • 제35권4호
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    • pp.48-56
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    • 2003
  • In this work an integrated model for paper plants combining wet-end and dry section is developed and a model predictive control scheme based on the plant model is proposed. Closed-loop process identification method is employed to produce a state-space model. Thick stock, filler flow, machine speed and steam pressure are selected as input variables and basis weight, ash content and moisture content are considered as output variables. The desired output trajectory is constructed in the form of 1st-order dynamics. Results of simulations for control of grade change operations are compared with plant operation data collected during the grade change operations under the same conditions as in simulations. From the comparison, we can see that the proposed model predictive control scheme reduces the grade change time and achieves stable steady-state.

회전자 바의 표피효과를 이용한 벡터제어용 유도전동기의 정지형 상수추정 (Parameter Identification of Vector-Controlled Induction Motor using Skin Effect of Rotor Bars at Standstill)

  • 권영수;문상호;이정흠;권병기;최창호;석줄기
    • 전력전자학회논문지
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    • 제13권6호
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    • pp.403-410
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    • 2008
  • 본 논문에서는 벡터제어에 필요한 유도전동기의 상수를 정지 상태에서 부가적인 신호 주입을 이용하여 추정하는 방법을 제안하였다. 농형 유도전동기 회전자 바의 표피효과를 수학적으로 모델링을 하고 분석하였다. 상수 추정을 위해 정지 상태에서 두 가지의 서로 다른 주파수의 신호를 주입한다. 전동기의 초기 상수를 알지 못하므로 개-루프 전압 주입방법 대신 폐-루프 전류제어 방법을 이용한다. 이 방법은 전기적 사고를 미리 방지할 수 있으므로 개-루프 전압 주입방법 보다 안전하다. 그리고 유도전동기의 상수 추정에 심각한 영향을 주는 위상지연효과를 보상하기 위한 오프라인 시험방법을 제안하였다. 그리고 제안된 상수 추정 방법의 타당성을 증명하기 위해 세 가지 용량의 유도전동기에 대해 실험을 수행하였다.

The identification of continuous-time systems within a closed-loop

  • Bae, Chul-Min;Wada, Kiyoshi;Imai, Jun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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    • pp.157-160
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    • 1996
  • Physical systems axe generally continuous-time in nature. However as the data measured from these systems is generally in the form of discrete samples, and most modern signal processing is performed in the discrete-time domain, discrete-time models are employed. This paper describes methods for estimating the coefficients of continuous-time system within a closed loop control system. The method employs a recursive estimation algorithm to identify the coefficients of a discrete-time bilinear-operator model. The coefficients of the discrete-time bilinear-operator model closely approximate those of the corresponding continuous-time Laplace transform transfer function.

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Modeling of Grade Change Operations in Paper Plants

  • 고준석;여영구;하성문;고두석;강홍
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2003년도 추계학술발표논문집
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    • pp.291-305
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    • 2003
  • In this work we developed the closed-loop model of a paper machine during grade change with the intention to provide a reliable dynamic model to be used in the model-based grade change control scheme. During the grade change, chemical and physical characteristics of paper process change with time. It is very difficult to represent these characteristics on-line by using physical process models. In this work, the wet circulation part and the drying section were considered as a single process and closed-loop identification technique was used to develop the grade change model. Comparison of the results of numerical simulations with plant operation data demonstrates the effectiveness of the model identified.

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Generalized predictive control based on the parametrization of two-degree-of-freedom control systems

  • Naganawa, Akihiro;Obinata, Goro;Inooka, Hikaru
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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    • pp.1-4
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    • 1995
  • We propose a new design method for a generalized predictive control (GPC) system based on the parametrization of two-degree-of freedom control systems. The objective is to design the GPC system which guarantees the stability of the control system for a perturbed plant. The design procedure of our proposed method consists of three steps. First, we design a basic controller for a nominal plant using the LQG method and parametrize a whole control system. Next, we identify the deviation between the perturbed plant and the nominal one using a closed-loop identification method and design a free parameter of parametrization to stabilize the closed-loop system. Finally, we design a feedforward controller so as to incorporate GPC technique into our controller structure. A numerical example is presented to show the effectiveness of our proposed method.

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수치 해석을 통한 자기 베어링 시스템의 모델링에 관한 연구 (A Study on Modeling for the Magnetic Bearing System by Numerical Analysis)

  • 심성효;최명수;김창화;문덕홍;양주호
    • 동력기계공학회지
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    • 제5권4호
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    • pp.53-60
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    • 2001
  • This paper considers a modeling for the MIMO magnetic bearing system. The rotor is flexible and has a complex shape. To obtain the nominal plant transfer functions, we perform a numerical analysis by using the finite element method(F.E.M.) for the rotor's dynamics, and make a nominal model by reducing the modes from the results. And, we have experimented on the frequency response by a closed-loop identification method, and compared it with the simulation's result on the closed-loop control system.

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Identification of the Closed Loop Systems using the Signal Compression Method

  • Toshitaka UMEMOTO;I, Tomoharu-Do;Shoichiro FUJISAWA;Takeo YOSHIDA
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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    • pp.318-322
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    • 1998
  • An Electro Magnetic Suspension System, which has two floating masses connected with springs and dampers, can not keep its equilibrium when it is solved as an ordinary quartic mathematical model. So, a two dimensional con-troller, designed with quadratic mathematical model assuming the two mass model to be a rigid body, was used. As the result, the system floated stably. Therefore, we measured the transfer performances of this closed loop system contained this controller using the compression signal method proposed by N.Aoshima and identified the parameters of this system. Finally, we compared these parameters with the computing results of quartic mathematical model.

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