• Title, Summary, Keyword: Predictive Control

Search Result 949, Processing Time 0.091 seconds

High precision Gating Algorithm for Predictive Current Control of Phase Controlled Rectifier (위상제어 정류기의 예측전류제어를 위한 새로운 고정밀 게이팅 알고리즘)

  • 정세종;송승호
    • The Transactions of the Korean Institute of Electrical Engineers B
    • /
    • v.53 no.3
    • /
    • pp.206-211
    • /
    • 2004
  • In phase controlled rectifier, it's been known that a fast response is achieved by predictive current control without any overshoot. The frequent sampling period is essential to improve the firing accuracy in conventional predict current control. However, improving the firing accuracy if difficult to reduce the period of sampling efficiently because current sampling and predictive current control is carried out in every period and the ON-OFF current control is performed by comparing two different one. To improve the firing accuracy at the predictive current control, the calculated firing angle is loaded into the high-accuracy hardware timer. So the calculation of exact crossing point between the predictive and actual current is the most important. In this paper, the flow chart for proposed firing angle calculation algorithm is obtained for the fastest current control performance in transient state. The performance of proposed algorithm is verified through simulations and experiments.

Improved Deadbeat Current Controller with a Repetitive-Control-Based Observer for PWM Rectifiers

  • Gao, Jilei;Zheng, Trillion Q.;Lin, Fei
    • Journal of Power Electronics
    • /
    • v.11 no.1
    • /
    • pp.64-73
    • /
    • 2011
  • The stability of PWM rectifiers with a deadbeat current controller is seriously influenced by computation time delays and low-pass filters inserted into the current-sampling circuit. Predictive current control is often adopted to solve this problem. However, grid current predictive precision is affected by many factors such as grid voltage estimated errors, plant model mismatches, dead time and so on. In addition, the predictive current error aggravates the grid current distortion. To improve the grid current predictive precision, an improved deadbeat current controller with a repetitive-control-based observer to predict the grid current is proposed in this paper. The design principle of the proposed observer is given and its stability is discussed. The predictive performance of the observer is also analyzed in the frequency domain. It is shown that the grid predictive error can be decreased with the proposed method in the related bode diagrams. Experimental results show that the proposed method can minimize the current predictive error, improve the current loop robustness and reduce the grid current THD of PWM rectifiers.

Robust Predictive Control of Robot Manipulators with Uncertainties (불확실 로봇 매니퓰레이터의 견실 예측 제어기 설계)

  • 김정관;한명철
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.10 no.1
    • /
    • pp.10-14
    • /
    • 2004
  • We present a predictive control algorithm combined with the robust robot control that is constructed on the Lyapunov min-max approach. Since the control design of a real manipulator system may often be made on the basis of the imperfect knowledge about the model, it is an important trend to design a robust control law that guarantees the desired properties of the manipulator under uncertain elements. In the preceding robust control work, we need to tune several control parameters in the admissible set where the desired stability can be achieved. By introducing an optimal predictive control technique in robust control we can find out much more deterministic controller for both the stability and the performance of manipulators. A new class of robust control combined with an optimal predictive control is constructed. We apply it to a simple type of 2-link robot manipulator and show that a desired performance can be achieved through the computer simulation.

Predictive Control for Mobile Robots Using Genetic Algorithms (유전알고리즘을 이용한 이동로봇의 예측제어)

  • Son, Hyun-sik;Park, Jin-hyun;Choi, Young-kiu
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.21 no.4
    • /
    • pp.698-707
    • /
    • 2017
  • This paper deals with predictive control methods of mobile robots for reference trajectory tracking control. Predictive control methods using predictive model are known as effective schemes that minimize the future errors between the reference trajectories and system states; however, the amount of real-time computation for the predictive control are huge so that their applications were limited to slow dynamic systems such as chemical processing plants. Lately with high computing power due to advanced computer technologies, the predictive control methods have been applied to fast systems such as mobile robots. These predictive controllers have some control parameters related to control performance. But these parameters have not been optimized. In this paper we employed the genetic algorithm to optimize the control parameters of the predictive controller for mobile robots. The improved performances of the proposed control method are demonstrated by the computer simulation studies.

Robust Predictive Control of Robot Manipulator with The Bound Estimation

  • Kim, Jung-Kwan;Han, Myung-Chul
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.155.5-155
    • /
    • 2001
  • The robust predictive control law which use the bound estimation is proposed for uncertain robot manipulators. Since the control design of a real manipulator system may often be made on the basis of the imperfect knowledge about model, it´s an important tend to design a robust control law that will guarantee the desired performance of the manipulator under uncertain elements. In the preceeding work, the robust predictive control law was proposed. In this work, we propose a class of robust predictive control of manipulators with the bound estimate technique and fe stability based on Lyapunov function is presented.

  • PDF

Predictive controller using weighted input (입력 가중치를 이용한 예측제어)

  • 나상섭;신세희;어영구
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.343-347
    • /
    • 1989
  • In this paper, predictive control method using actual applied input which is the weighted summation of past inputs is presented. In conventional predictive control methods, a set of control inputs is computed and in these only the first element is applied to the process at each time instant. But this predictive control method based on conventional methods considers all computed control inputs. Consequently, the characteristic of response and the reliability of the control scheme in the case of imperfact model are improved.

  • PDF

A study on the adaptive predictive control of steam-reforming plant using bilinear model (쌍일차 모델을 이용한 스팀개질 플랜트의 적응예측제어에 관한 연구)

  • 오세천;여영구
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.156-159
    • /
    • 1996
  • An adaptive predictive control for steam-reforming plant which consist of a steam-gas reformer and a waste heat steam-boiler was studied by using MIMO bilinear model. The simulation experiments of the process identification were performed by using linear and bilinear models. From the simulation results it was found that the bilinear model represented the dynamic behavior of a steam-reforming plant very well. ARMA model was used in the process identification and the adaptive predictive control. To verify the performance and effectiveness of the adaptive predictive controller proposed in this study the simulation results of steam-reforming plant control based on bilinear model were compared to those of linear model. The simulation results showed that the adaptive predictive controller based on bilinear model provides better performance than those of linear model.

  • PDF

Imposed Weighting Factor Optimization Method for Torque Ripple Reduction of IM Fed by Indirect Matrix Converter with Predictive Control Algorithm

  • Uddin, Muslem;Mekhilef, Saad;Rivera, Marco;Rodriguez, Jose
    • Journal of Electrical Engineering and Technology
    • /
    • v.10 no.1
    • /
    • pp.227-242
    • /
    • 2015
  • This paper proposes a weighting factor optimization method in predictive control algorithm for torque ripple reduction in an induction motor fed by an indirect matrix converter (IMC). In this paper, the torque ripple behavior is analyzed to validate the proposed weighting factor optimization method in the predictive control platform and shows the effectiveness of the system. Therefore, an optimization method is adopted here to calculate the optimum weighting factor corresponds to minimum torque ripple and is compared with the results of conventional weighting factor based predictive control algorithm. The predictive control algorithm selects the optimum switching state that minimizes a cost function based on optimized weighting factor to actuate the indirect matrix converter. The conventional and introduced weighting factor optimization method in predictive control algorithm are validated through simulations and experimental validation in DS1104 R&D controller platform and show the potential control, tracking of variables with their respective references and consequently reduces the torque ripple.

Temperature control of a batch polymerization reactor using nonlinear predictive control algorithm (비선형 예측제어 알고리즘을 이용한 회분식 중합 반응기의 온도제어)

  • 나상섭;노형준;이현구
    • 제어로봇시스템학회:학술대회논문집
    • /
    • /
    • pp.1000-1003
    • /
    • 1996
  • Nonlinear unified predictive control(UPC) algorithm was applied to the temperature control of a batch polymerization reactor for polymethylmethacrylate(PMMA). Before the polymerization reaction is initiated, the parameters of the process model are determined by the recursive least squares(RLS) method. During the reaction, nonlinearities due to generation of heat of reaction and variation of heat transfer coefficients are predicted through the nonlinear model developed. These nonlinearities are added to the process output from the linear process model. And then, the predicted process output is used to calculate the control output sequence. The performance of nonlinear control algorithm was verified by simulation and compared with that of the linear unified predictive control algorithm. In the experiment of a batch PMMA polymerization, nonlinear unified predictive control was implemented to regulate the temperature of the reactor, and the validity of the nonlinear model was verified through the experimental results. The performance of the nonlinear controller turned out to be superior to that of the linear controller for tracking abrupt changes in setpoint.

  • PDF

A Modeling of Proportional Pressure Control Valve and its Control (비례전자 감압밸브의 모델링과 제어)

  • Yang, K.U.;Lee, I.Y.
    • Journal of the Korea Society For Power System Engineering
    • /
    • v.6 no.3
    • /
    • pp.71-77
    • /
    • 2002
  • In this study, a dynamic model of proportional pressure control valve using the bond graph and a predictive controller are presented in the form of dynamic matrix control which is concerned with a design method of digital controller for the electro hydraulic servo system. The bond graph can be utilized for all types of systems which involve power and energy, and it is applied to a propotional pressure control valve in this study. Recently, many researchers suggested that better control performance could be obtained by means of the predictive controls with future reference input, future control output and future control error. The Predictive controller is very practical because the controller can be easily applicable to a personal computer or a microprocessor. This study investigates through numerical simulations that hydraulic system with the predictive controller shows very good control performances.

  • PDF