• 제목/요약/키워드: Cascade Controller

검색결과 79건 처리시간 0.024초

천정크레인의 무진동/위치 제어기 개발에 관한 연구 (A Study on the Anti-Swing and Position Controller for the Overhead Cranes)

  • 윤지섭;강이석
    • 대한기계학회논문집
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    • 제19권6호
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    • pp.1391-1401
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    • 1995
  • This paper addresses design procedure and testing results of a closed-loop motion control of the cranes. When the object is stopped at the desired position, swinging occurs, and such swinging deteriorates the safety and efficiency of the operation of the crane. Therefore, in this paper, the cascade anti-swing and trolley position feedback controller are designed. Anti-swing controller rapidly eliminates swinging of object and position feedback controller reduces the trolley position error. The performance of this controller is investigated through the computer simulation and experiment. From the results of a series of computer simulations and experiments it can be concluded that proposed controller effectively reduces swinging of the object and trolley position error, which shows this controller can be used as an effective tool for the precise control of overhead cranes.

A New Scheme for Maintaining Balanced DC Voltages in Static Var Compensator(SVC) Using Cascade Multilevel Inverter

  • Min, Wan-Ki;Min, Joon-Ki;Choi, Jae-Ho
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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    • pp.561-565
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    • 2001
  • This paper proposes a new switching scheme of a static var compensator(SVC) with cascade multilevel inverter which employs H-bridge inverter(HBI). To improve the un­balanced problem of the DC capacitor voltages, the rotated switching scheme of fundamental frequency is newly used. The optimized fundamental switching pattern with low switching frequency is adapted to be suitable for high application. The selective harmonic elimination method(SHEM) allows to keep the total harmonic distortion(THD) low in the output voltage of multilevel inverter. The SVC system is modeled using the d-q transform which calculates the instantaneous reactive power. This model is used to design a controller and analyze the SVC system. Simulated and experimental results are also presented and discussed to validate the proposed schemes.

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직렬형 멀티레벨 인버터를 사용한 무효전력보상장치의 직류전압평형을 위한 새로운 제어기법 (A New Control Scheme for Maintaining Balanced DC Voltages in Static Var Compensator(SVC) Using Cascade Multilevel Inverter)

  • 민완기;민준기;최재호
    • 전기학회논문지P
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    • 제54권4호
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    • pp.179-184
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    • 2005
  • This paper examines the application of high voltage static var compensator(SVC) with cascade multilevel inverter which employs H-bridge inverter(HBI). A new switching scheme is developed for the SVC system. To improve the unbalanced problem of the DC capacitor voltages, the rotated switching scheme of fundamental frequency is newly used. The optimized fundamental switching pattern with low switching frequency is adapted to be suitable for high application. The selective harmonic elimination method(SHEM) allows to keep the total harmonic distortion(THD) low in the output voltage of multilevel inverter. The SVC system is modeled using the d-q transform which calculates the instantaneous reactive power. This model is used to design a controller and analyze the SVC system. Simulated and experimental results are also presented and discussed to validate the proposed schemes.

대전력용 직렬형 멀티레벨 인버터 이용한 STATCOM의 새로운 제어기법 (Novel Control of STATCOM Using Cascade Multilevel Inverter for High Power Application)

  • 민완기;최재호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2000년도 학술대회 논문집 전문대학교육위원
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    • pp.136-141
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    • 2000
  • This paper proposes the novel control of a static synchronous compensator (STATCOM). This STATCOM system consists of cascade multilevel inverter which employs H-bridge inverter(HBI) The STATCOM system is modeled in the d-q transform matrix. This model is used to design a controller. The selective harmonic elimination method(SHEM) allows to keep the total harmonic distortion (THD) low in the output voltage. The switching method produces the staircase type waveform in cascade multilevel inverter. To balance the DC voltages in HBIs capacitor, the rotated switching scheme is newly proposed in this paper. The proposed control scheme is verified in the simulated results.

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불연속 제어 서보시스템에서의 chattering 저감을 위한 hyperstable cascade control (A hyperstable cascade control scheme for chattering reduction in discontinously controlled servo systems)

  • 윤태웅;최익;김광배
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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    • pp.154-159
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    • 1988
  • In this paper, a hyperstable cascade control scheme for servo drive systems is proposed to reduce the chattering, which is an undesirable property in discontinuously controlled systems. First, a discontinuously controlled hyperstable MRAC scheme is designed with respect to PI speed control system using only output variables, and then a linear position controller is cascaded. It is shown that the above system is asymptotically stable and the chattering is greatly reduced at a constant speed provided that the disturbance torque satisfies a certain condition.

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Improvement on Sensorless Vector Control Performance of PMSM with Sliding Mode Observer

  • Wibowo, Wahyu Kunto;Jeong, Seok-Kwon;Jung, Young-Mi
    • 동력기계공학회지
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    • 제18권5호
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    • pp.129-136
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    • 2014
  • This paper proposes improvement on sensorless vector control performance of a permanent magnet synchronous motor (PMSM) with sliding mode observer. An adaptive observer gain and second order cascade low-pass filter (LPF) were used to improve the estimation accuracy of the rotor position and speed. The adaptive observer gain was applied to suppress the chattering intensity and obtained by using the Lyapunov's stability criterion. The second order cascade LPF was designed for the system to escalate the filtering performance of the back-emf estimation. Furthermore, genetic algorithm was used to optimize the system PI controller's performance. Simulation results showed the effectiveness of the suggested improvement strategy. Moreover, the strategy was useful for the sensorless vector control of PMSM to operate on the low-speed area.

직렬형 멀티레벨 인버터를 사용한 대용량 무효전력 보상장치의 파라메타 설계 (Design of Parameters for High Power Static Var Compensator Used Cascade Multilevel Inverter)

  • 민완기;최재호
    • 전기학회논문지P
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    • 제52권4호
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    • pp.172-178
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    • 2003
  • This paper examines the application of high voltage static var compensator(SVC) with cascade multilevel inverter which employs H-bridge inverter(HBI). This method has the primary advantage that the number of voltage levels can be increased for a given number of semiconductor devices when compared to the conventional control methods. The SVC system is modeled using the d-q transform which calculates the instantaneous reactive power. This model is used to design a controller and analyze the SVC system. From the mathematical model of the system, the design procedures of the circuit parameters L and C are presented in this thesis. To meet the specific total harmonic distortion(THD) and ripple factor of the capacitor voltage, the circuit parameters L and C are designed. Simulated and experimental results are also presented and discussed to validate the proposed schemes.

고정이득 궤환 안정화를 위한 충분조건 (A Sufficient condition for constant gain feedback stabilization)

  • Kang, Hwan-Il
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.1167-1170
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    • 1999
  • We consider a negative unity feedback control system in which a controller and a given minimum phase transfer function are in cascade. This paper present a sufficient condition for the existence of a constant gain controller under which the overall closed loop characteristic polynomial is stable. This sufficient condition is based on Lehnigk's lemmas.

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H-infinity Loop Shaping 방법을 이용한 BLDC 전동기 핀 위치제어시스템 제어기 설계 (Controller Design of BLDC Motor Fin Position Servo System by Employing H-infinity Loop Shaping Method)

  • 주학림;목형수;이형근;한수희;서현욱
    • 전력전자학회논문지
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    • 제24권1호
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    • pp.49-55
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    • 2019
  • This study proposes a robust control of a fin position servo system using the H-infinity loop-shaping method. The fin position control system has a proportional (P) position controller and a proportional-integral (PI) controller. In this work, the position control loop requires a wide bandwidth. No current control loop exists due to the compact design of the system. Hence, the controller parameters are difficult to determine using the traditional cascade design method. The $H_{\infty}$ controller design method is used to design the controller's gain to achieve good performance and robustness. First, the transfer function of the system, which can be divided into tunable and fixed parts, is derived. The tunable part includes the position P controller and speed PI controller. The fixed part includes the rest of the system. Second, the optimized controller parameters are calculated using Matlab $H_{\infty}$ controller design program. Finally, the system with optimized controller is tested by simulation and experiment. The control performance is satisfactory, and the $H_{\infty}$ controller design method is proven to be valid.

구호로봇용 연성 매니퓰레이터를 위한 조인트 제어 및 충돌감지 알고리즘 (Development of Joint Controller and Collision Detection Methods for Series Elastic Manipulator of Relief Robot)

  • 정병진;김태근;원건;김동섭;황정훈
    • 로봇학회논문지
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    • 제13권3호
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    • pp.157-163
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    • 2018
  • This paper deals with the development and application of control algorithms for series elastic relief robots for rescue operations in harsh environment like disasters or battlefield. The joint controller applied in this paper has a cascade structure combining inner loop for torque control and outer loop for position control. The torque loop contains feedforward and feedback controller and disturbance observer for independent, decentralized joint control. The effect of the elastic component and motor dynamics are treated as the nonlinear disturbance and compensated with the disturbance observer of torque controller. For the collision detection, Band Designed Disturbance Observer is configured to recognize/respond to external disturbance robustly in the continuously changing environment. The controller is applied to a 7-dof series elastic manipulator to evaluate the torque tracking and collision detection/response performance.