• Title/Summary/Keyword: reduced-order control

Search Result 1,367, Processing Time 0.029 seconds

Identification of Aerodynamic Model CFD-Based for Gust Response Analysis

  • Nie, Xueyuan;Yang, Guowei
    • International Journal of Aerospace System Engineering
    • /
    • v.2 no.1
    • /
    • pp.43-46
    • /
    • 2015
  • Aeroelastic gust response analysis plays an important role in design of aircrafts. For gust response analysis, frequency domain aerodynamics method has been typically used with generalized aerodynamic influence coefficient matrices at various reduced frequencies. However, it cannot be applied to the aeroservoelastic analysis, such as gust alleviation control. Time-domain state space (SS) models must be built. It attacks little attention that gust response analysis relies on continuous gust time-domain input signal in terms of its PSD function. The aim the current study is to provide a reduced-order modeling (ROM) method based on CFD to model gust responses for continuous gust responses for continuou gust inputs in time domain. The paper analyzed the gust response of AGARD445.6 wing subjected to the Dryden gust with ROMs and compared the difference between the rigid structure and elastic one. The results demonstrate that structure elastic effect effect should be considered in the design of aircraft.

Dynamic Decoupler Design for EGR and VGT Systems in Passenger Car Diesel Engines (승용디젤엔진 EGR 및 VGT 제어시스템의 동적특성을 고려한 Decoupler 설계 연구)

  • Hong, Seungwoo;Park, Inseok;Sohn, Jeongwon;Sunwoo, Myoungho
    • Transactions of the Korean Society of Automotive Engineers
    • /
    • v.22 no.2
    • /
    • pp.182-189
    • /
    • 2014
  • This paper proposes a decoupler design method to reduce interaction between exhaust gas recirculation (EGR) and variable geometry turbocharger (VGT) systems in passenger car diesel engines. The EGR valve and VGT vane are respectively used to control air-to-fuel ratio (AFR) of exhaust gas and intake pressure. A plant model for EGR and VGT systems is defined by a first order transfer function plus time-delay model, and the loop interaction between these systems is analyzed using a relative normalized gain array (RNGA) method. In order to deal with the loop interaction, a design method for simplified decoupler is applied to this study. Feedback control algorithms for AFR and intake pressure are composed of a compensator using PID control method and a prefilter. The proposed decoupler is evaluated through engine experiment, and the results successfully showed that the loop interaction between EGR and VGT systems can be reduced by using the proposed decoupler. Furthermore, it presents stable performance even off from the designed operating point.

Sliding mode control of small form factor optical pick-up actuator using PZT (PZT를 이용한 초소형 광 픽업 엑츄에이터의 슬라이딩 모드 제어)

  • Lee, Woo-Chul;Jung, Dong-Ha;Park, Tae-Wook;Park, No-Cheol;Yang, Hyun-Seok
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2003.11a
    • /
    • pp.424-429
    • /
    • 2003
  • This paper proposes a swing-arm type dual-stage actuator, which consists of a PZT actuator for fine motion and a VCM(Voice Coil Motor) for coarse motion, for SFF ODD(Small Form Factor Optical Disk Drive), in order to achieve fast access speed and precise track following control. We focus our attention on the design and control of the PZT actuator, because there have been a lot of previous researches related to the VCM and dual-stage actuators. Due to the dual cantilever structure, the PZT actuator can generate precise translational tracking motion at its tip where optical pickup is attached at, and the effect of hysteric behavior of the PZT element is reduced. The dynamic model of the PZT actuator is derived by using the Hamilton's principle, and verified by comparing with the experimental frequency response. The sliding mode control is designed in order to be robust against modeling uncertainties. Simulations and experimental results confirm the effectiveness of the suggested control scheme.

  • PDF

Model Following Acceleration Control Strategy for the Robustness Control of DC Servo Position Control Systems (직류서보 위치제어시스템의 강인성 제어를 위한 모델추종 가속도제어기법)

  • Park, Young-Jeen;Cha, Min;You, Young-Suk;Hong, Soon-Chan
    • Proceedings of the KIEE Conference
    • /
    • 1996.07a
    • /
    • pp.270-273
    • /
    • 1996
  • A scheme of observer-based MFAC(Model Following Acceleration Control) system is proposed for the robustness control of DC servo position control systems. The proposed system is composed of LMFC, variable structure feedback controller, and reduced-order state observer. As the servo motor is controlled by the acceleration command, the total servo system becomes the acceleration control system. Simulation results show that the proposed system have robust properties against parameter variations and external disturbances.

  • PDF

Study on active vibration control based on wave viewpoint using the longitudinal wave separation method (종파 분리 방법을 이용한 파동 관점의 능동 진동 제어)

  • Jung, Byung-Bo;Park, Young-Jin;Park, Youn-Sik
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2007.05a
    • /
    • pp.928-933
    • /
    • 2007
  • In this research, we investigated active vibration control based on wave-viewpoint using the longitudinal wave separation method. The control strategy is the one of active vibration control technique for generating vibration reduced zone and uses wave information including the directivity as the cost function. In order to get the wave information from the measured values, we proposed and examined the time-domain longitudinal wave separation method proper to real time application like active vibration control. Using the proposed method, we examine the performance and feasibility of active vibration control based wave view-point through the simulation. The related experimental verification and application is going to be expected in a near future.

  • PDF

Anti-sway Control of Crane System using Time Optimal Control Method (최단시간 제어법을 이용한 크레인의 흔들림 방지제어)

  • 이진우;김상봉
    • Journal of the Korean Society of Safety
    • /
    • v.12 no.3
    • /
    • pp.23-29
    • /
    • 1997
  • In the control of crane system, the traversing time of the trolley must be reduced as much as possible and the swing must be stopped at the end point. To design the minimum time control system, Pontryagim maximum principle is applied. In order to implement the control algorithm, the dynamic equation is linearlized at an equilibrium point, so that the linear time invariant state equation can be obtained. The overall performance of the closed loop system is evaluated by means of computer simulations and practical experiments in a broad range of working conditions. The effectiveness is proved through the experimental results for the anti-sway control of the load and the position control of trolly. It is expected that the proposed system will make an important contribution to the industrial fields.

  • PDF

Intelligent Control Method Using Genetic Algorithm and Fuzzy Logic Controller (유전자 알고리즘과 퍼지 논리 제어기를 이용한 지능 제어 방식)

  • 김주웅;이승형;엄기환
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.5 no.7
    • /
    • pp.1374-1383
    • /
    • 2001
  • In the fuzzy control method behaves more robustness than conventional control method, we propose a intelligent control method that membership functions and scaling factor of the fuzzy logic controller are optimized by genetic algorithm under off-line, and then fuzzy logic controller is constructed by the optimization parameters under on-line. In order to verify the usefulness of the proposed control method, we are applied to one link manipulator, and confirmed that the proposed control method is reduced the fuzzy rule base and is the better performance than the conventional fuzzy control method.

  • PDF

Applications of Block Pulse Response Circulant Matrix and its Singular Value Decomposition to MIMO Control and Identification

  • Lee, Kwang-Soon;Won, Wan-Gyun
    • International Journal of Control, Automation, and Systems
    • /
    • v.5 no.5
    • /
    • pp.508-514
    • /
    • 2007
  • Properties and potential applications of the block pulse response circulant matrix (PRCM) and its singular value decomposition (SVD) are investigated in relation to MIMO control and identification. The SVD of the PRCM is found to provide complete directional as well as frequency decomposition of a MIMO system in a real matrix form. Three examples were considered: design of MIMO FIR controller, design of robust reduced-order model predictive controller, and input design for MIMO identification. The examples manifested the effectiveness and usefulness of the PRCM in the design of MIMO control and identification. irculant matrix, SVD, MIMO control, identification.

Nonlinear Observer-based Control of Synchronous Machine Drive System

  • Sundrica, Marijo;Erceg, Igor;Maljkovic, Zlatko
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.3
    • /
    • pp.1035-1047
    • /
    • 2015
  • Starting from a new dynamic system description novel synchronous machine deterministic observers are proposed. Reduced and full order adaptive observer variations are presented. Based on the feedback linearization control law and the use of deterministic observer a novel control system is built. It meets the requirements of high performance tracking system. Adaptivity to stator and rotor resistance and the torque sensorless application is included. The comparison of the proposed novel control with conventional linear and nonlinear control systems is discussed. The given simulational study includes complete drive system integration.

Predictive control theory and design for offshore platforms

  • C.C. Hung;T. Nguyen;C.Y. Hsieh
    • Ocean Systems Engineering
    • /
    • v.14 no.1
    • /
    • pp.73-84
    • /
    • 2024
  • In order to achieve the best performance, the automatic control with advanced technology is made of sheathed steel to withstand a wide range of wave loads. This model shows how to control the vibration of the fiber panel as a solution using the new results from the Lyapunov stability question, a modification of the bat that making it easy to calculate and easy to use. It is used to reduce the storage space required in this system. The results show that the planned worker can compensate effectively for the unplanned delay. The results show that the proposed controller can compensate for delays and errors. Fuzzy control (predictive control) demonstrated the external vibration can be reduced.