서지주요정보
PID controller tuning based on process models and interfacing model predictive controller with low level PID loops = 공정 모델에 의거한 PID 제어기의 튜닝 방법과 모델 예측 제어기를 하위 PID 루프에 연결하는 방법에 관한 연구
서명 / 저자 PID controller tuning based on process models and interfacing model predictive controller with low level PID loops = 공정 모델에 의거한 PID 제어기의 튜닝 방법과 모델 예측 제어기를 하위 PID 루프에 연결하는 방법에 관한 연구 / Yong-Ho Lee.
저자명 Lee, Yong-Ho ; 이용호
발행사항 [대전 : 한국과학기술원, 1998].
Online Access 원문보기 원문인쇄

소장정보

등록번호

8009271

소장위치/청구기호

학술문화관(문화관) 보존서고

DCHE 98021

휴대폰 전송

도서상태

이용가능

대출가능

반납예정일

초록정보

This study developed new methods for controller design for SISO systems, integrating and unstable processes, cascade control systems and MIMO systems. This study also developed how to interface model predictive controller (advanced control system) with low level loops(e.g. PID loops). First, the IMC-PID approach is generalized and how to obtain PID parameters for general process model is proposed. PID parameters are obtained for general process models by approximating the feedback form of an IMC controller with a Maclaurin series in the Laplace domain. These PID parameters yield closed-loop responses that are closer to the desired responses than those obtained by PID controllers tuned by other methods. The improvement in closed-loop control performance becomes more prominent as the dead time of the process model increases. Second, a new design method for two degree of freedom controllers is proposed in this thesis. Such controllers are essential for unstable processes, and provide significantly improved dynamic performance over single degree of freedom controllers for stable processes when the disturbances enter through the process. Third, a new method for PID controller tuning based on process models for integrating and unstable processes with time delay is proposed. The method consists of first finding the ideal controller that gives the desired closed loop response and then finding the PID approximation of the ideal controller by Maclaurin series. Closed-loop responses with the controllers tuned by the proposed method are compared with those tuned by the existing methods. The results show that the proposed tuning method is simpler to use and gives better closed loop performance than the existing methods. Fourth, a new method for PID controller tuning based on process models for cascaded control systems is proposed. This method can be applied to any open loop stable processes. Furthermore, it enables us to tune the PID controllers both for the inner-loop and the outer-loop simultaneously while existing tuning methods tune the inner loop first and the outer loop next. Closed-loop responses of cascade control loops tuned by the proposed method are compared with those tuned by existing methods such as the frequency response method and the ITAE method. The results show that the proposed tuning method is superior to the existing methods Fifth. a new tuning method for multiloop PID controllers is proposed. The controller by the proposed method makes a closed loop response of each loop follows the corresponding desired closed-loop response as close as possible. The closed-loop frequency response method is used with the interaction weighting factor. which incorporates the interaction effect into the tuning rules effectively. in order to minimize the gap of the closed loop frequency response between output and desired trajectory over a significant frequency range. As a result, the PID controller tuned by the proposed method gives good and robust performance. Two examples for 2x2 and 3x3 systems are used to illustrate the proposed method. The results show that the proposed method is superior to the conventional methods such as the BLT tuning method and the empirical tuning method. Finally. how to interface model predictive controllers with low-level loops is proposed. Two options for implementing an advanced model-based control system on a process with low-level PID loops are discussed. Strengths and drawbacks of the two options are examined and modifications are proposed. Simulation results of a CSTR and a distillation column are presented to demonstrate the performance improvements resulting from the modifications.

서지기타정보

서지기타정보
청구기호 {DCHE 98021
형태사항 x, 145 p. : 삽도 ; 26 cm
언어 영어
일반주기 저자명의 한글표기 : 이용호
지도교수의 영문표기 : Sun-Won Park
지도교수의 한글표기 : 박선원
학위논문 학위논문(박사) - 한국과학기술원 : 화학공학과,
서지주기 Includes references
주제 PID tuning
SISO systems
Cascade systems
Unstable systems
MIMO systems
Model predictive controller
Subspace identification
비례 적분 미분 제어기
다단계 제어
불안정 공정
다중입력 다중 출력계
모델 예측 제어
모델 인식
QR CODE qr code