Robust controllers for variable reluctance motors

This paper investigates the control problem of variable reluctance motors (VRMs). VRMs are highly nonlinear motors; a model that takes magnetic saturation into account is adopted in this work. Two robust control schemes are developed for the speed control of a variable reluctance motor. The first control scheme guarantees the uniform ultimate boundedness of the closed loop system. The second control scheme guarantees the exponential stability of the closed loop system. Simulation results of the proposed controllers are presented to illustrate the theoretical developments. The simulations indicate that the proposed controllers work well, and they are robust to changes in the parameters of the motor and to changes in the load.

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Adaptive Stabilization Control for a Class of Complex Nonlinear Systems Based on T-S Fuzzy Bilinear Model

Mathematical Problems in Engineering ◽

10.1155/2015/659521 ◽

2015 ◽

Vol 2015 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Jinsheng Xing ◽

Naizheng Shi

Keyword(s):

Adaptive Control ◽

Nonlinear Systems ◽

Complex Systems ◽

Closed Loop ◽

Loop System ◽

Asymptotically Stable ◽

Bilinear Model ◽

Closed Loop System ◽

Fuzzy Modelling ◽

Control Scheme

This paper proposes a stable adaptive fuzzy control scheme for a class of nonlinear systems with multiple inputs. The multiple inputs T-S fuzzy bilinear model is established to represent the unknown complex systems. A parallel distributed compensation (PDC) method is utilized to design the fuzzy controller without considering the error due to fuzzy modelling and the sufficient conditions of the closed-loop system stability with respect to decay rateαare derived by linear matrix inequalities (LMIs). Then the errors caused by fuzzy modelling are considered and the method of adaptive control is used to reduce the effect of the modelling errors, and dynamic performance of the closed-loop system is improved. By Lyapunov stability criterion, the resulting closed-loop system is proved to be asymptotically stable. The main contribution is to deal with the differences between the T-S fuzzy bilinear model and the real system; a global asymptotically stable adaptive control scheme is presented for real complex systems. Finally, illustrative examples are provided to demonstrate the effectiveness of the results proposed in this paper.

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Robust attitude fault-tolerant control for unmanned autonomous helicopter with flapping dynamics and actuator faults

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331218775477 ◽

2018 ◽

Vol 41 (5) ◽

pp. 1266-1277 ◽

Cited By ~ 12

Author(s):

Kun Yan ◽

Mou Chen ◽

Qiangxian Wu ◽

Ke Lu

Keyword(s):

Closed Loop ◽

Fault Tolerant ◽

Fault Tolerant Control ◽

Loop System ◽

System Stability ◽

Actuator Faults ◽

Closed Loop System ◽

Attitude Tracking ◽

Control Scheme ◽

Autonomous Helicopter

In this paper, an adaptive robust fault-tolerant control scheme is developed for attitude tracking control of a medium-scale unmanned autonomous helicopter with rotor flapping dynamics, external unknown disturbances and actuator faults. For the convenience of control design, the actuator dynamics with respect to the tail rotor are introduced. The adaptive fault observer and robust item are employed to observe the actuator faults and eliminate the effect of external disturbances, respectively. A backstepping-based robust fault-tolerant control scheme is designed with the aim of obtaining satisfactory tracking performance and closed-loop system stability is proved via Lyapunov analysis, which guarantees the convergence of all closed-loop system signals. Simulation results are given to show the effectiveness of the proposed control method.

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A Parametric Study of the Modified Model Reference Adaptive Control Scheme

Journal of Vibration and Acoustics ◽

10.1115/1.2893902 ◽

1998 ◽

Vol 120 (3) ◽

pp. 814-821

Author(s):

H. M. Sardar ◽

M. Ahmadian

Keyword(s):

Closed Loop ◽

Simulation Analysis ◽

Adaptive Controller ◽

Loop System ◽

Closed Loop System ◽

Model Reference ◽

Modified Model ◽

Control Scheme ◽

Inertial Nonlinearities ◽

Model Reference Adaptive

The validity of the claim by many studies that the damping and stiffness forces can be ignored when designing a model reference adaptive controller, is examined. For a simple plant, the sensitivity of the closed loop system to the inertial, damping, and stiffness nonlinearities are investigated, through a simulation analysis. It is shown that the closed loop system is sensitive to the changes in the inertial nonlinearities, and relatively insensitive to variations in the damping and stiffness forces. This supports the assumption made in many previous studies.

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A FICTITIOUS REFERENCE ITERATIVE TUNING (FRIT) IN THE TWO-DEGREE OF FREEDOM CONTROL SCHEME AND ITS APPLICATION TO CLOSED LOOP SYSTEM IDENTIFICATION

IFAC Proceedings Volumes ◽

10.3182/20050703-6-cz-1902.00105 ◽

2005 ◽

Vol 38 (1) ◽

pp. 626-631 ◽

Cited By ~ 21

Author(s):

Osamu Kaneko ◽

Shotaro Soma ◽

Takao Fujii

Keyword(s):

System Identification ◽

Closed Loop ◽

Loop System ◽

Degree Of Freedom ◽

Closed Loop System ◽

Control Scheme ◽

Two Degree Of Freedom

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Output Feedback Algorithm for Nonlinear Systems with Compensation of Bounded Disturbances and Measurement Noises

Mekhatronika Avtomatizatsiya Upravlenie ◽

10.17587/mau.20.3-15 ◽

2019 ◽

Vol 20 (1) ◽

pp. 3-15 ◽

Cited By ~ 1

Author(s):

I. B. Furtat ◽

P. A. Gushchin ◽

A. A. Peregudin

Keyword(s):

Output Feedback ◽

Closed Loop ◽

Sufficient Conditions ◽

Loop System ◽

Partial Recovery ◽

Closed Loop System ◽

External Disturbances ◽

Control Schemes ◽

Measurement Noises ◽

Feedback Algorithm

The output feedback algorithm for dynamic plants with compensation of parametric uncertainty, external disturbances and measurement noises is synthesized. The plants are described by a nonlinear system of differential equations with vector input and output signals. Unlike most existing control schemes in this paper the dimensions of the measurement interference and the output signal are equal, the sources of the signals of disturbances and disturbances are different, parametric and external disturbances can be present in any equation of the plant model. For simultaneous compensation of disturbances and measurement noises it is proposed to consider two channels. On the first channel a part of the measurement noises will be estimated which will allow partial recovery the information about the plant noisy output. On the second channel the disturbances will be compensated. Thus, at least two independent measurement channels are required for simultaneous compensation of disturbances and measurement noises. Sufficient conditions for calculating the parameters of the algorithm in the form of solvability of the linear matrix inequality are obtained. It is shown that the equation of a closed-loop system obtained on the basis of the proposed algorithm depends on the disturbances and the smallest component of the measurement noise. However, if the smallest component cannot be identified a priory, the results of the transients depend on the component of the noise that will be selected in the synthesis of the control system. Thus, unlike most existing control schemes, where the equation of a closed-loop system depends on disturbance and noise, the resulting algorithm provides better transients, because they do not depend on the entire noise vector, but only on its smallest (one) component. The simulations for a third-order nonlinear plant and the synchronization of an electrical generator connected to the power grid are presented. Numerical examples illustrate the effectiveness of the proposed scheme and the robustness with respect to random components in the noises and disturbances.

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Efficient Application of Automation Technology in Thickener Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1094.441 ◽

2015 ◽

Vol 1094 ◽

pp. 441-444

Author(s):

Dan Dan Xie ◽

Xiong Tong ◽

Xian Xie ◽

Kai Hou ◽

Ji Yong Li

Keyword(s):

Automatic Control ◽

Closed Loop ◽

Programmable Logic Controller ◽

Loop System ◽

Ecological Environment ◽

Programmable Logic ◽

Closed Loop System ◽

Positive Side ◽

Control Scheme ◽

Automation Technology

The text mainly introduced the thickener’s front technology and also talked about the process of using flocculent addition and the emissions of underflow density presenting a more optimal automatic control scheme on the basis of the original automatic project. Using automatic control components like PLC programmable logic controller and the control elements of the inverter make the thickener in a whole closed-loop system for the flocculant addition and the density of the ore and the process of discharge. It will bring a positive side for our economic, social and ecological environment.

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A Robustly Stable Multiestimation-Based Adaptive Control Scheme for Robotic Manipulators

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2196418 ◽

2005 ◽

Vol 128 (2) ◽

pp. 414-421 ◽

Cited By ~ 11

Author(s):

A. Ibeas ◽

M. de la Sen

Keyword(s):

Adaptive Systems ◽

Closed Loop ◽

Sudden Change ◽

Robotic Manipulators ◽

Adaptive Controller ◽

Time Instant ◽

Loop System ◽

System Stability ◽

Closed Loop System ◽

Control Scheme

A multiestimation-based robust adaptive controller is designed for robotic manipulators. The control scheme is composed of a set of estimation algorithms running in parallel along with a supervisory index proposed with the aim of evaluating the identification performance of each one. Then, a higher-order level supervision algorithm decides in real time the estimator that will parametrize the adaptive controller at each time instant according to the values of the above supervisory indexes. There exists a minimum residence time between switches in such a way that the closed-loop system stability is guaranteed. It is verified through simulations that multiestimation-based schemes can improve the transient response of adaptive systems as well as the closed-loop behavior when a sudden change in the parameters or in the reference input occurs by appropriate switching between the various estimation schemes running in parallel. The closed-loop system is proved to be robustly stable under the influence of uncertainties due to a poor modeling of the robotic manipulator. Finally, the usefulness of the proposed scheme is highlighted by some simulation examples.

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Robust Passivity-based Control scheme for 1.26 KW PEM Fuel Cell under temperature and load variations

Journal of Electrochemical Energy Conversion and Storage ◽

10.1115/1.4051331 ◽

2021 ◽

pp. 1-10

Author(s):

Abdelaziz Zaidi ◽

Asma Charaabi ◽

Oscar Barambones ◽

Nadia Zanzouri

Keyword(s):

Closed Loop ◽

Sliding Mode ◽

Load Resistance ◽

Current Sensor ◽

Closed Loop System ◽

Load Variations ◽

Load Variation ◽

Incremental Value ◽

Control Scheme ◽

Control Schemes

Abstract The Model Based System Engineering (MBSE) is based on simplified mathematical models that reflects the dynamic behavior of the systems. These latter are most of time nonlinear and need control schemes taking in consideration exogenous perturbations. The main contribution of this paper is the design of a robust passivity based sliding mode control scheme for a 1.26 KW PEMFC. The uncertainties considered in this paper are temperature and load variation. The FC reference current is adapted in a linear transformation by introducing a temperature sensor. This information is present in most of commercial PEMFC and not used in the closed-loop system. Moreover, the proposed approach cancels the errors caused by the average approach modeling and the observer (the part which replaces current sensor). Robustness against load variation is assured via a proportional integral compensation of the incremental value of load resistance. The performance of the controller and the effectiveness of our approach is shown through the simulation with MATLAB-SIMULINK software.

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Passive Feedforward Approach to Bilateral Teleoperated Manipulators

10.1115/imece2000-2425 ◽

2000 ◽

Author(s):

Perry Y. Li ◽

Dongjun Lee

Keyword(s):

Work Environment ◽

Internal Energy ◽

Closed Loop ◽

Internal State ◽

Loop System ◽

Closed Loop System ◽

Control Scheme ◽

Control Objective

Abstract A control scheme for linear dynamically similar bilateral teleoperated manipulator system which ensures that the closed loop system is energetically passive is proposed. Energetic passivity implies that the teleoperated manipulator system is safe to interact with, and that the coupling between the system and any strictly passive environment is stable. The control objective is for the two manipulators in the system to behave in unison under the influence of both the operator and the work environment, while maintaining energetic passivity. The dynamics of the system in unison and its response to the operator and work environment can be specified as kinematic and power scalings. To maintain energetic passivity with feedback and feedforward actions, the proposed control makes use of two fictitious internal energy storages. The result is that when the internal state of the storage elements are suitably initialized, the teleoperated manipulator system achieves asymptotic locking even in the presence of external (bounded) forcing from the operator and work environment.

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