• Title, Summary, Keyword: Disturbance Observer

Search Result 593, Processing Time 0.037 seconds

Time-domain Approaches for Input Disturbance Observer

  • Kim, Kyung-Soo
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.22-25
    • /
    • 2005
  • In the paper, algorithms for disturbance observers are newly presented in the time-domain. Attention is paid to observing a ramp disturbance by introducing an integral term to the output equation of a constant disturbance observer. In order to reduce the sensitivity to the measurement noise, the disturbance observer is combined with the state observer. It will be shown that the estimation dynamics can be arbitrarily chosen by assigning the eigenvalues of a characteristic equation. Also, we provide the analysis of observer behaviors subject to non-ramp-style disturbances. Finally, we propose the generalized disturbance observer that accurately estimates disturbances of higher order in time series expansion.

  • PDF

Disturbance Observer based PID Controller for robustness enhancement of UAVs under the presence of wind disturbance (무인항공기의 내풍성 강화를 위한 제어기의 외란관측기 연구)

  • Oh, Seungjo;Lee, Dongjin
    • Journal of the Korean Society for Aviation and Aeronautics
    • /
    • v.26 no.2
    • /
    • pp.61-67
    • /
    • 2018
  • This paper presents a method to apply disturbance observer to PID controller for robustness enhancement of UAVs. The system uncertainties and disturbances bring adverse effects on performance and stability of UAVs. In this paper, we estimate the acceleration disturbances using nonlinear disturbance observer, then compensate disturbances with composite controller. By employing nonlinear disturbance observer and composite controller, we have better performance and robustness than conventional PID controller. The asymptotical stability of nonlinear disturbance observer is presented through theoretical analysis. The estimation performance of nonlinear disturbance observer is evaluated by numerical simulation. And performance of disturbance observer based PID controller is evaluated by comparing the performance with conventional PID controller.

Design of a Model-Based Low-Order Disturbance Observer to Estimate a Sinusoidal Disturbance with Unknown Constant Offset (미지의 상수 오프셋을 갖는 삼각함수 외란 추정을 위한 모델기반 저차 외란 관측기 설계)

  • Lee, Cho-Won;Son, Young Ik
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.65 no.4
    • /
    • pp.652-658
    • /
    • 2016
  • In practical control systems differences between nominal and real systems arise from internal uncertainties and/or external disturbances. This paper presents a model-based low-order disturbance observer for a sinusoidal disturbance with unknown constant offset. By using the disturbance model of a biased harmonic signal, the proposed method can successfully estimate the biased sinusoidal disturbance with unknown amplitude and phase but known frequency. At the first stage of the observer design, a model-based disturbance observer is designed when all the system states are measurable. Next, a sufficient condition is presented for the proposed observer to estimate the sinusoidal disturbance with a minimal-order additional dynamics using only output measurement. Comparative computer simulations are performed to test the performance of the proposed method. The simulation results show the enhanced performance of the proposed disturbance observer.

The Robust Position Control of Induction Motors using a Binary Disturbance Observer (바이너리 외란관측기를 이용한 유도전동기의 견실한 위치제어)

  • Han, Yun-Seok;Choe, Jeong-Su;Kim, Yeong-Seok
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.48 no.4
    • /
    • pp.203-211
    • /
    • 1999
  • A control approach for the robust position control of induction motors based on the binary disturbance observer is described. The conventional binary disturbance observer is used to remove the chattering problem of a sliding mode disturbance observer. However, the steady state error may exist in the conventional binary disturbance observer because it estimates external disturbance with a constant boundary layer. In order to overcome this problem, new binary disturbance observer with an integral augmented switching hyperplane is proposed. The robustness is achieved, and the continuous control is realized by employing the proposed observer without the chattering problem and the steady state error. The effectiveness of the proposed observer is confirmed by the comparative experimental results.

  • PDF

Robust control of motor systems via a novel disturbance observation technique (새로운 외란관측기를 이용한 모터시스템의 강인제어)

  • 송성호;김점근
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.199-202
    • /
    • 1997
  • In this paper, a novel disturbance observer is proposed in order to regulate the disturbance in motor systems. The proposed observer does not require the implementation of ideal derivative of the state since the inverse of the nominal model is not used in the design of the observer. The transfer gain from a disturbance to the output of the disturbance observer is one. So, there is no time-delay in the response due to the dynamics of the observer.

  • PDF

The Improved Binary Disturbance Observer for the Position Control of Induction Motors (유도전동기의 위치제어를 위한 개선된 바이너리 외란관측기)

  • 한윤석;김영석;김상욱
    • Proceedings of the KIPE Conference
    • /
    • /
    • pp.249-254
    • /
    • 1998
  • A control approach for the robust position control of induction motors based on the improved binary disturbance observer is described. The conventional binary disturbance observer is used to remove the chattering problem of a sliding mode disturbance observer. However, the steady state error may be existed in the conventional binary disturbance observer because it estimates external disturbance with a constant boundary layer. In order to overcome this problem, a new binary disturbance observer with an integral augmented switching hyperplane is improved. The robustness is achieved, and the continuous control is realised by employing the improved observer without the chattering problem and the steady state error. The effectiveness of the improved observer is confirmed by the comparative experimental results.

  • PDF

Compensation of Sinusoidal Disturbance in Pendubot System using Disturbance Observer (외란 추정기를 이용한 펜듀봇 시스템의 사인파형 외란 보상)

  • Jeon, Jeong-Hyo;Kim, Cheol-Joong;Chwa, Dong-Kyoung
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.59 no.12
    • /
    • pp.2278-2283
    • /
    • 2010
  • This paper deals with the pendubot control using disturbance observer. Experimental results for the motion of pendubot with balancing control show that the limit cycle can be attributed to the disturbance. Therefore, we propose the disturbance compensation method using by disturbance observer to compensate for the disturbance. Through the experimental results, the effectiveness of the proposed method is verified.

Novel Fuzzy Disturbance Observer based on Backstepping Method For Nonlinear Systems (비선형 시스템에서의 백스테핑 기법을 이용한 새로운 퍼지 외란 관측기 설계)

  • Baek, Jae-Ho;Lee, Hee-Jin;Park, Mig-Non
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.47 no.2
    • /
    • pp.16-24
    • /
    • 2010
  • This paper is proposed a novel fuzzy disturbance observer based on backstepping method for nonlinear systems with unknown disturbance. Using fuzzy logic systems, a fuzzy disturbance observer with the disturbance observation input is introduced for unknown disturbance. To guarantee that the proposed disturbance observer estimates the unknown disturbance, the disturbance observation error dynamic system is employed. Under the framework of the backstepping design, the fuzzy disturbance observer is constructed recursively and an adaptive laws and the disturbance observation input are derived. Numerical examples are given to demonstrate the validity of our proposed disturbance observer for nonlinear systems.

Design of Unknown Disturbance and Current Observer for Electric Motor Systems (전동기 시스템의 미지외란 및 전류 관측기 설계)

  • Lee, Myoungseok;Jung, Kyungmo;Kong, Kyoungchul
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.21 no.7
    • /
    • pp.615-620
    • /
    • 2015
  • DOB (Disturbance Observer) is an useful control method for estimating the disturbance applied to dynamic systems. Disturbance observer can be used to implement a robust control system to generate a control input for rejecting the disturbance, and it can be also used to estimate the disturbance to obtain information. The system that uses disturbance estimation is investigated for high performance control such as automatic door systems, walking robot and electric power steering system in vehicles. In this paper, a novel disturbance observer which is called disturbance and current observer for estimating load torque in the motor system is proposed. The difference between the DOB for disturbance rejection and DCOB is mathematically verified. Current and angular velocity are required for estimating the load torque of the motor in DOB. However, the DCOB can estimate load torque and current without current sensor. DCOB is designed based on modeling of the motor system. Appropriate Q-filter is selected and the applicability of DCOB is verified by simulation. The estimated disturbance and current of the electric motor can be verified without current sensor, as experiments of the actual motor system.

Design of Adaptive Disturbance Observer for the Time Delay System Control (시간지연 시스템 제어를 위한 적응외란관측자 설계)

  • Lee, Soon-Young
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.56 no.9
    • /
    • pp.1676-1679
    • /
    • 2007
  • In control of the time delay systems, if the disturbance information can be estimated exactly, the ideal response for the disturbance can be achieved. Therefore, in this paper, a new adaptive disturbance observer for the time delay system control is proposed. The disturbance observer is designed and adaptive laws for adjusting the observer are proposed. The new Smith predictor controller to eliminate the effects of the disturbance can be achieved by adding an estimated disturbance to the Smith model. The improved performances of the proposed system and the adaptive disturbance observer are verified by computer simulation.