• 제목/요약/키워드: saturation control

검색결과 792건 처리시간 0.023초

Saturation Compensation of a DC Motor System Using Neural Networks

  • Jang, Jun-Oh;Ahn, Ihn-Seok
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제5권2호
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    • pp.169-174
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    • 2005
  • A neural networks (NN) saturation compensation scheme for DC motor systems is presented. The scheme that leads to stability, command following and disturbance rejection is rigorously proved. On-line weights tuning law, the overall closed loop performance and the boundness of the NN weights are derived and guaranteed based on Lyapunov approach. The simulation and experimental results show that the proposed scheme effectively compensate for saturation nonlinearity in the presence of system uncertainty.

입력 신호의 크기에 제한을 갖는 2차 시스템에 대한 슬라이딩 모드 제어기의 슬라이딩 평면의 설계 (Design of Sliding Surface of a Sliding Mode Controller for a Second Order System with Input Saturation)

  • 한소희;손성한;박강박
    • 제어로봇시스템학회논문지
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    • 제10권11호
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    • pp.1095-1099
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    • 2004
  • In this paper, a novel sliding surface is proposed to guarantee that the sliding mode controller for a second order system produces a control signal whose magnitude is always within the bound of input saturation. The proposed sliding surface uses a time-varying function, and its time derivative works to make a control signal within the bounds of input saturation. Simulation results are presented to show the effectiveness of the proposed method.

입력제한이 존재하는 상태지연 시스템의 동적보상방법 (Dynamic Compensation Method for State Delayed Control Systems with Input Saturation)

  • 박종구
    • 대한전기학회논문지:시스템및제어부문D
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    • 제50권7호
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    • pp.325-331
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    • 2001
  • A dynamic anti-windup method for state delayed control systems with input saturation is considered. Under the assumption that a linear controller has been designed for a state delayed control system based on the existing design technique which shows desirable nominal performance, an additional compensator is incorporated to provide a graceful performance degradation despite of input saturation. By regarding the difference of the controller states in the absence and presence of input saturation as an objective function, the dynamic compensator which minimizes it is determined explicitly. The proposed dynamic compensator is the closed form of plant and controller parameters. The proposed method not only provides graceful performance degradation, but it also guarantees the total stability of resulting systems. An illustrative example is provided to show the effectiveness of the proposed method.

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스트로크 포화를 고려한 직렬 복합형 감쇠기의 비선형 제어 (Nonlinear Control of Cascade Hybrid Mass Dampers considering Stroke Saturation)

  • 민경원;황성호;김성춘;호경찬;김인수
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 가을 학술발표회논문집
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    • pp.377-386
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    • 2000
  • Hybrid mass dampers consist of passive tuned mass dampers and active mass dampers. They have the advantage that passive tuned mass dampers are still operated even when active mass dampers are stopped by excessive disturbances or power failure. This paper begins first with the comparative analysis of tuned mass dampers, hybrid mass dampers, and active mass dampers. Next more detailed study is carried out on the hybrid mass dampers: cascade hybrid mass dampers (CHMD) and active tuned mass dampers (ATMD). CHMD is regarded as more reasonable device because of its lighter active mass than ATMD's. However CHMD can not neglect stroke saturation problem caused by the length limitation of active damper mass. We compensate the saturation problem with nonlinear restoring force. The restoring force is calculated based on the states and phases of active mass dampers and added to the control force. It is shown that the presented compensation method prevents CHMD from saturation behavior without apparent changes of control force and responses compared to those in case of not considering the saturation problem.

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포화현상을 고려한 슬라이딩 모드제어기의 최대제어력 산정 (Maximum Control Force for Sliding Mode Controller with Saturation Problem)

  • 이상현;민경원;김홍진;이영철
    • 한국지진공학회논문집
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    • 제8권2호
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    • pp.1-8
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    • 2004
  • 제어효과가 탁월한 능동제어알고리듬의 하나인 슬라이딩 모드제어(SMC)는 지진력을 받는 구조물의 제어를 위해 매우 큰 크기의 제어력을 요구한다. 따라서, SMC의 설계에 있어 제어기의 포화문제는 반드시 고려되어야 한다. 본 논문은 설계응답스펙트럼에 따른 구조율의 복원력을 이용하여 제어기의 최대 제어력을 결정하는 방법을 제안한다. 한 개 혹은 다수의 제어장치를 설치한 다층건물의 수치해석 결과는 제안된 방법이 지진하중을 받는 구조물의 포화 슬라이딩모드제어에 유효함을 보며준다.

선형 구조물의 능동 진동 제어를 위한 포화 제어기의 안정성 (Stability of Saturation Controllers for the Active Vibration Control of Linear Structures)

  • 문석준;임채욱;허영철
    • 한국지진공학회논문집
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    • 제10권6호
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    • pp.93-102
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    • 2006
  • 대형 구조물에 작용하는 큰 외력은 능동 제어 장치의 제어입력에 포화를 종종 유발한다. 그리고 구조물이 대형화될수록 질량, 강성 등의 파라미터들에 대한 정확한 값을 알기가 어려워지므로, 수학적인 모델과 실제 구조물과의 모델링 오차는 파라미터들에 대한 불확실성으로 제어기의 설계 시에 고려되어야 한다. 그러므로 건축 및 토목 구조물에 대한 능동 진동 제어 방법을 다룰 때 제어기의 안정성을 보장하기 위하여 제어입력의 포화와 계의 파라미터 불확실성을 동시에 고려한 강인 포화 제어기의 설계가 필요하다. 여기에서는 건물의 능동 진동 제어에 연구 및 적용되어진 여러 제어기들 중에서 선형 최적 제어기 LQR, 수정된 뱅뱅 제어기, 포화 슬라이딩 모드 제어기, 강인 포화 제어기의 안정성을 살펴본다. 특히 제안된 강인 포화 제어기의 필요성을 보이기 위하여 LQR, 수정된 뱅뱅 제어기, 포화 슬라이딩 모드 제어기들이 제어입력의 포화나 파라미터 불확실성이 존재하는 경우에 불안정해지는 현상들을 보인다. 2자유도 진동계에 대한 수치 예제와 능동 질량 감쇠기(AMD)를 이용한 2층 구조물에 대한 실험을 통하여 강인 포화 제어기의 강인 안정성을 보인다.

구동기포화를 갖는 불확실한 시스템의 H2 제어 ([ H2 ] Control of Uncertain Systems with Actuator Saturation)

  • 최현철;홍석교;좌동경
    • 제어로봇시스템학회논문지
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    • 제13권10호
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    • pp.1000-1006
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    • 2007
  • This paper presents an LMI-based method to design a saturated state-feedback $H_2$ controller for uncertain systems with actuator saturation. Specifically, the paper proposes a sufficient condition such that the system under norm-bounded uncertainties and actuator saturation is asymptotically stable and the $H_2$-norm of the system has an upper-bound. The resulting condition is further utilized to solve a convex optimization problem specified in the context of $H_2$-norm minimization, whose solution yields a saturated $H_2$ controller. A numerical example is presented to show the effectiveness of the proposed method.

제한된 구동기 용량을 갖는 시간지연 선형시스템의 $H_{\infty}$ 제어 ([ $H_{\infty}$ ] Control of Time-Delayed Linear Systems with Limited Actuator Capacities)

  • 이연규;김진훈
    • 전기학회논문지
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    • 제56권9호
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    • pp.1648-1654
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    • 2007
  • In this paper, we consider the design of $H_\infty$ high-gain state feedback control for time-delayed linear systems with limited actuator capacities. The high-gain control means that the control permits the predetermined degree of saturation. Based on new Lyapunov-Krasovskii functional, we derive a result in the form of matrix inequalities. The matrix inequalities are consisted of LMIs those confirm the positive definiteness of Lyapunov- Krasovskii functional, satisfaction of predetermined degree of saturation, reachable set and $L_2$ gain constraint. The result is dependent on the bound of time-delay and its rate, predetermined degree of saturation, actuator capacity, and the allowed size of disturbances. Finally, we give a numerical example to show the effectiveness and usefulness of our result.

Disturbance observer-based robust backstepping load-following control for MHTGRs with actuator saturation and disturbances

  • Hui, Jiuwu;Yuan, Jingqi
    • Nuclear Engineering and Technology
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    • 제53권11호
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    • pp.3685-3693
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    • 2021
  • This paper presents a disturbance observer-based robust backstepping load-following control (DO-RBLFC) scheme for modular high-temperature gas-cooled reactors (MHTGRs) in the presence of actuator saturation and disturbances. Based on reactor kinetics and temperature reactivity feedback, the mathematical model of the MHTGR is first established. After that, a DO is constructed to estimate the unknown compound disturbances including model uncertainties, external disturbances, and unmeasured states. Besides, the actuator saturation is compensated by employing an auxiliary function in this paper. With the help of the DO, a robust load-following controller is developed via the backstepping technique to improve the load-following performance of the MHTGR subject to disturbances. At last, simulation and comparison results verify that the proposed DO-RBLFC scheme offers higher load-following accuracy, better disturbances rejection capability, and lower control rod speed than a PID controller, a conventional backstepping controller, and a disturbance observer-based adaptive sliding mode controller.

노리개젖꼭지 제공이 미숙아의 심박동수, 산소포화도 및 행동상태에 미치는 효과 (Effects of Nonnutritive Sucking on Heart Rate, Oxygen Saturation and Behavioral State in Premature Infants)

  • 박진희;박호란
    • Child Health Nursing Research
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    • 제13권3호
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    • pp.299-307
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    • 2007
  • Purpose: To investigate the effect of nonnutritive sucking(NNS) on the heart rate, oxygen saturation, and behavioral state of premature infants. Method: From December 15, 2004 to February 15, 2005, 20 premature infants hospitalized in the neonatal intensive care units were assigned to an experimental group (10), or a control group (10). Circular pacifiers for premature infants (Johnson, U.S.A.), which had been packed with $2{\times}2$ gauzes to create a vacuum, were used for 5 minutes, one hour after feeding for 5 days. Heart rates and oxygen saturation were checked every minute for 10 minutes once a day and behavioral states were monitored through video recording at the same time. Results: Changes in heart rate, oxygen saturation and behavioral state were found to show significant differences between the experimental group and the control group according to the point in time, and interactions were found between the group and the point of time. However, for behavioral state, no significant difference was found between the experimental group and the control group after the NNS was removed. Conclusion: From the results of this study it is possible to conclude that NNS is a positive intervention to bring about increased oxygen saturation and soothed behavioral state for premature infants.

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