ORCID Profile
0000-0001-8901-836X
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Publisher: Committee of Automatic Control and Robotics PAS
Date: 2022
Publisher: IEEE
Date: 12-2018
Publisher: Springer Science and Business Media LLC
Date: 28-10-2018
Publisher: IEEE
Date: 29-09-2022
Publisher: IEEE
Date: 10-2017
Publisher: Springer Science and Business Media LLC
Date: 21-04-2021
DOI: 10.1007/S40313-021-00707-Y
Abstract: The chaotic support structures for offshore wind turbines are often subjected to a severe environment. A robust control scheme needs to be considered to maintain them in a safe operational limit. Robust sliding mode control (SMC) scheme can provide an excellent robust controller against this severe and challenging environment for these chaotic structures. This paper proposes a novel fixed-time adaptive sliding mode control scheme with a state observer to synchronize chaotic support structures for offshore wind turbines in the presence of matched parametric uncertainties. The proposed controller is a new integration of adaptive control concept, SMC method, fixed-time stability concept and a state observer. A fixed-time stability concept is used to provide stability for the system within a presented time regardless of initial conditions. The adaptive concept is utilized to provide an online estimator of the uncertain upper bound. Also, a nonlinear observer is employed to provide an online estimator of an unmeasured state in the controller. Lyapunov stability theorem is used to analyze fixed-time stability of the system based on SMC methodology. The simulation results demonstrate that the proposed controller is able to ensure fixed-time synchronization along with providing precise means to estimate the unmeasured state as well as uncertainty upper bound.
Publisher: Inderscience Publishers
Date: 2022
Publisher: IEEE
Date: 02-2018
Publisher: Polish Academy of Sciences Chancellery
Date: 26-07-2023
Publisher: Institution of Engineering and Technology (IET)
Date: 23-03-2021
DOI: 10.1049/CSY2.12012
Publisher: Springer Science and Business Media LLC
Date: 14-05-2020
Publisher: Inderscience Publishers
Date: 2019
Publisher: Hindawi Limited
Date: 27-06-2022
DOI: 10.1155/2022/3758220
Abstract: In this paper, a novel adaptive finite-time sliding mode backstepping (AFSMBS) control scheme is suggested to control a type of high-order double-integrator systems with mismatched disturbances and uncertainties. A robust sliding mode backstepping control method, adaptive control method, and finite-time stability notion are incorporated to provide a better tracking performance over applying them in idually and to use their benefits simultaneously. The concept of a sliding mode is used to define a new form of a backstepping controller. The adaptive control method is utilized to adaptively estimate the upper bounds of the disturbances and uncertainties and the estimated data are used in the control low. The notion of the finite-time stability is incorporated with the suggested control scheme to ensure the system’s convergence within a finite time. The stability proof is obtained for the closed-loop system in a finite time utilizing the Lyapunov stability theorem. Simulation results are obtained for an ex le of a remotely operated vehicle (ROV) with three degrees of freedom (3-DOF) to demonstrate the efficacy of the suggested control approach.
Publisher: MDPI AG
Date: 17-12-2021
DOI: 10.3390/EN14248522
Abstract: The three-area power system is widely considered a suitable ex le to test load frequency control of the distributed generation system. In this article, for such a system, for the power stabilization task, we introduce two controllers: Linear Quadratic Regulator (LQR), which is model-based, and Fuzzy Logic Controller (FLC), which is data-based. The purpose is to compare the two approaches from the point of view of (i) ease of implementation and tuning, and (ii) robustness to changes in the model. The model, together with controls strategies, has been implemented in the MATLAB software. Then, it has been tested for different simulation scenarios, taking into account the disturbances and faulty tie-lines between areas. Various quality measures allow to compare the performance of each control strategy. The comparison in terms of parameter change and load disturbances prompt us to propose suitable metrics and advice notes on the application of each controller.
Publisher: Allerton Press
Date: 07-2020
Publisher: Wiley
Date: 22-06-2021
DOI: 10.1002/ADC2.81
Abstract: It is essential to consider chattering alleviation of Sliding Mode Control (SMC) design along with providing the system convergence regardless of initial states utilizing the fixed‐time stability notion. Unknown states and disturbance are two major issues in practical applications, which can be effectively solved by using sliding mode observers. This paper deals with state and disturbance Observers‐based Chattering‐Free Fixed‐time SMC (OCFFSMC) design for a class of high‐order nonlinear systems with unknown disturbance, while only the first state is measured physically. A new form of the combined observer‐controller is designed to provide estimated data of unknown disturbance and unmeasured states in the control law. The designed disturbance observer‐based sliding mode controller is not only capable of estimating unknown disturbance but also capable of alleviating the chattering problem in the control signal. Based on defining a new form of the sliding surface, a new control law is designed to alleviate chattering problem and achieve trajectory tracking in a fixed time independently of initial conditions. The fixed‐time stability proof of the closed‐loop system is obtained using Lyapunov stability theory. The validity of the proposed control scheme, OCFFSMC, is verified by applying two ex les and simulating in Simulink/MATLAB.
Publisher: Wiley
Date: 07-03-2023
DOI: 10.1002/ASJC.3052
Abstract: This paper investigates a fixed‐time convergence issue using the sliding mode observer‐based controller for a class of uncertain nonlinear double integrator systems. This observer‐based controller is designed assuming that only the first state measurement is available and there is no information about external disturbances and modeling uncertainties. A new form of sliding mode observer in combination with a sliding mode controller is designed to estimate unmeasured state and unknown disturbances and uncertainties as well as provide the estimated data in the control law. A novel form of sliding surfaces for the robust observer‐based controller is proposed for which fixed‐time convergence is guaranteed to achieve trajectory tracking. In the proposed fixed‐time scheme, the bound on the settling time is user‐defined using design parameters regardless of the system's initial conditions. The control law and observer law are designed such that the chattering issue is alleviated in the control signal. The stability analysis of the closed‐loop system using the observer‐based controller is established via the Lyapunov theory. The validity of the controller design is tested by applying and simulating an ex le of a robot manipulator in Simulink/MATLAB. The superiority of the proposed method is demonstrated by comparing it with two other methods from the relevant literature.
Publisher: Wiley
Date: 05-10-2020
DOI: 10.1002/ADC2.52
Publisher: IEEE
Date: 12-2018
Publisher: Springer Science and Business Media LLC
Date: 13-05-2023
Publisher: Wiley
Date: 25-04-2023
DOI: 10.1002/RNC.6719
Publisher: IEEE
Date: 02-2018
Publisher: Springer Science and Business Media LLC
Date: 18-05-2020
No related grants have been discovered for Ali Soltani Sharif Abadi.