Loading...
Search for: pole-placement
0.006 seconds
Total 25 records

    Fuzzy pole placement for speed control in D.C. motor

    , Article Recent Advances in Electrical and Electronic Engineering ; Volume 11, Issue 1 , March , 2018 , Pages 15-20 ; 23520965 (ISSN) Kharabian, B ; Mohammad Shahri, A ; Mousavi Mashhadi, S .K ; Samsaam, S ; Sharif University of Technology
    Bentham Science Publishers B.V  2018
    Abstract
    Background: in this paper, fuzzy pole placement control approach is proposed to control the speed of D.C motor. In this method, state feedback gain is tuned by fuzzy logic. Methods: In conventional pole placement control, constant gain is considered to insert the poles of system in the desired place. Therefore, unnecessary effort is appliedto the system, and the system implementation becomes costly. In contrast, in fuzzy pole placement control, poles of system alter gradually based on the performance of system and are settled in desired point causing the system to display apposite performance. In other words, in conventional pole placement, a determined pair of poles exists, whereas in fuzzy... 

    Control of Unstable Non-minimum-phase Delayed Systems

    , M.Sc. Thesis Sharif University of Technology Rezaei, Sabereh (Author) ; Shahrokhi, Mohammad (Supervisor)
    Abstract
    The Smith Predictor does not work for unstable plants; therefore a lot of modifications have been proposed in order to solve this problem. In this project, advantages and disadvantages of most of these methods are studied in a general framework and based on Diophantine equation and using pole-placement technique. a discrete control scheme for unstable processes has been proposed. This structure can be used for non-minimum phase and stochastic processes. Robust stability of the suggested control structure has been shown. Performance of the proposed method is compared with previous works through computer simulations and its superiority for robust stability, load rejection; set-point tracking... 

    Robust controller design for discrete unstable non-minimum-phase delayed stochastic processes

    , Article International Journal of Control, Automation and Systems ; Volume 11, Issue 5 , 2013 , Pages 893-902 ; 15986446 (ISSN) Rezaei, S ; Shahrokhi, M ; Sharif University of Technology
    2013
    Abstract
    Control of unstable non-minimum-phase delayed stochastic processes is a challenging problem. In this work based on the Diophantine equation and using pole-placement technique, a discrete control scheme for such processes has been proposed. Robust stability of the suggested control structure has been shown. Advantages of the proposed scheme over the existing algorithms have been shown through computer simulations. It has been shown that performance of the proposed scheme for handling model mismatch and colored noise is superior to the previous work proposed in the literature  

    Stabilization of unstable fixed points of chaotic fractional order systems by a state fractional PI controller

    , Article European Journal of Control ; Volume 14, Issue 3 , 2008 , Pages 247-257 ; 09473580 (ISSN) Tavazoei, M. S ; Haeri, M ; Sharif University of Technology
    Lavoisier  2008
    Abstract
    This paper presents a new method to control chaos in fractional order systems based on the fractional control theory. The proposed controller is a fractional P1 (PIα) controller and can locally stabilize unstable equilibrium points of a class of chaotic fractional order systems. Using the ideas available in the chaos control methods such as On-Grebogi-Yorke (OGY), this local stabilization can be extended to the global stabilization. The controller has simple structure and its parameters can be determined by pole placement technique. To illustrate its capability, the proposed controller is applied to control chaos in the fractional order unified system. Numerical simulations confirm the... 

    Performance analysis of CDM as an AQM congestion controller in dynamic networks

    , Article EUROCON 2005 - The International Conference on Computer as a Tool, Belgrade, 21 November 2005 through 24 November 2005 ; Volume I , 2005 , Pages 680-683 ; 142440049X (ISBN); 9781424400492 (ISBN) Bigdeli, N ; Haeri, M ; Sharif University of Technology
    IEEE Computer Society  2005
    Abstract
    The performance of a new robust AQM strategy for dynamically varying TCP/AQM networks is proposed. Network variations include in both network topology and traffic variations. The developed AQM is designed based on Coefficient Diagram Method (CDM), which is a new indirect pole placement method that considers the speed, stability and robustness of the closed loop system in terms of time domain specifications. Simulation results show different features of the proposed method. ©2005 IEEE  

    Robust regulation and tracking system design for multivariable control of the tape transport mechanism

    , Article Microsystem Technologies ; Vol. 18, Issue. 5 , 2012 , pp. 557-573 ; ISSN: 09467076 Moradi, H ; Bakhtiari-Nejad, F ; Alasty, A ; Sharif University of Technology
    Abstract
    Tape mechanisms must be able to transport the tape with a constant velocity for achieving high rate of data transfer. In this paper, a multivariable model of tape transport mechanism including the take-up and supply reel servos for tape tension control and capstan servo for speed control is considered. To achieve desired performance,pole-placement approach based on general canonical control form (GCCF) is used. Instead of using expensive tension sensors, an observer is designed. A regulator system is developed for disturbance rejection; and a modified integral control is designed for perfect tracking of desired setpoints in tape speed and tensions. Since the real dynamic model associates... 

    Intelligent control of chaos using linear feedback controller and neural network identifier

    , Article Communications in Nonlinear Science and Numerical Simulation ; Volume 17, Issue 12 , 2012 , Pages 4731-4739 ; 10075704 (ISSN) Sadeghpour, M ; Khodabakhsh, M ; Salarieh, H ; Sharif University of Technology
    2012
    Abstract
    A method for controlling chaos when the mathematical model of the system is unknown is presented in this paper. The controller is designed by the pole placement algorithm which provides a linear feedback control method. For calculating the feedback gain, a neural network is used for identification of the system from which the Jacobian of the system in its fixed point can be approximated. The weights of the neural network are adjusted online by the gradient descent algorithm in which the difference between the system output and the network output is considered as the error to be decreased. The method is applied on both discrete-time and continuous-time systems. For continuous-time systems,... 

    Robust regulation and tracking system design for multivariable control of the tape transport mechanism

    , Article Microsystem Technologies ; Volume 18, Issue 5 , 2012 , Pages 557-573 ; 09467076 (ISSN) Moradi, H ; Bakhtiari Nejad, F ; Alasty, A ; Sharif University of Technology
    2012
    Abstract
    Tape mechanisms must be able to transport the tape with a constant velocity for achieving high rate of data transfer. In this paper, a multivariable model of tape transport mechanism including the take-up and supply reel servos for tape tension control and capstan servo for speed control is considered. To achieve desired performance,pole-placement approach based on general canonical control form (GCCF) is used. Instead of using expensive tension sensors, an observer is designed. A regulator system is developed for disturbance rejection; and a modified integral control is designed for perfect tracking of desired setpoints in tape speed and tensions. Since the real dynamic model associates... 

    Combining pole placement and online empirical mode decomposition methods to adaptive active control of structural vibration

    , Article Journal of Vibration and Acoustics, Transactions of the ASME ; Volume 141, Issue 4 , 2019 ; 10489002 (ISSN) Momeni Massouleh, S. H ; Hosseini Kordkheili, S. A ; Navazi, H. M ; Bahai, H ; Sharif University of Technology
    American Society of Mechanical Engineers (ASME)  2019
    Abstract
    Using a combination of the pole placement and online empirical mode decomposition (EMD) methods, a new algorithm is proposed for adaptive active control of structural vibration. The EMD method is a time-frequency domain analysis method that can be used for nonstationary and nonlinear problems. Combining the EMD method and Hilbert transform, which is called Hilbert-Huang transform, achieves a method that can be implemented to extract instantaneous properties of signals such as structural response dominant instantaneous frequencies. In the proposed algorithm, these estimated instantaneous properties are utilized to improve the pole-placement method as an adaptive active control technique. The... 

    Analysis & Vibration Control of a Rotating Beam with Variable Properties of the Cross Section

    , M.Sc. Thesis Sharif University of Technology Sahlolbeye, Zahra (Author) ; Moradi, Hamed (Supervisor)
    Abstract
    The purpose of this project is to model a rotating beam with variable properties of the cross section and also to present an active control method for suppressing the undesired vibrations due to external loading. The beam is modeled as a cantilever Euler-Bernoulli beam with nonuniform physical and geometrical properties. For a practical example, the characteristics of a wind turbine blade was used to solve the problem. The analyzed blade in this study is NREL 5-MW wind turbine blade. But the method can be extended to be used for other blades as well . First the natural frequencies and modeshapes were computed by MATLAB. Then by applying pole placement method, a control strategy was designed... 

    Simulation and Control of a Nonlinear and Non-Minimum Phase Bioreactor

    , M.Sc. Thesis Sharif University of Technology Baghbeheshti, Mostafa (Author) ; Shahrokhi, Mohammad (Supervisor)
    Abstract
    Control of fermentation bioreactors with nonlinear behavior is a very important issue, especially when optimizing the biomass production is desired. The system in this situation works in two domains: minimum phase and non-minimum phase; and in transition from one domain into the other one the sign of process gain changes. For control of such a process in this work have been used two non-adaptive strategies and one adaptive strategy. The non-adaptive schemes are pole-placement and model predictive. The pole-placement technique as a linear control algorithm is used and its parameters are fixed by minimizing the objective function which has been used in predictive control technique. Another... 

    Stabilization and Pole-Placement by Structurally-Constrained Controllers: A Graph-Theoretic Approach

    , M.Sc. Thesis Sharif University of Technology Moushaee, Pegah (Author) ; Babazadeh, Maryam (Supervisor)
    Abstract
    This thesis presents a new approach to design structural output feedback controllers with stabilization and pole-placement at desired points on the S plane. It is assumed that the linear time-invariant system has no fixed mode corresponding to the specified control structure, outside the desired region of the closed-loop poles, such that the structural controller design problem is theoretically feasible. To this end, the structural output controller design problem is first transformed into a structurally equivalent problem based on the solution of a set of discrete linear programs. Then, by using the resultant structure, a new method is proposed for designing static and dynamic control loops... 

    PID-Fuzzy control of air handling units in the presence of uncertainty

    , Article International Journal of Thermal Sciences ; Volume 109 , 2016 , Pages 123-135 ; 12900729 (ISSN) Moradi, H ; Setayesh, H ; Alasty, A ; Sharif University of Technology
    Elsevier Masson SAS 
    Abstract
    Air-handling unit (AHU) is one of the most complex installations that its control is necessary for maintaining satisfactory comfort conditions in buildings with low energy utilization. In this paper, a multivariable nonlinear and minimum phase model of the AHU is considered in the presence of uncertainties. The controller design is divided into two types. The first controller type is for the linearized plant based on decoupled PID-Fuzzy and PD-type Fuzzy controllers. The second type is based on full matrix PID-Fuzzy and pole-placement controllers in which interaction effects are considered. The indoor temperature and relative humidity are controlled via manipulation of valve positions of air... 

    Optimal tuning of temporary droop structure governor in the hydro power plant

    , Article 2008 IEEE 2nd International Power and Energy Conference, PECon 2008, Johor Baharu, 1 December 2008 through 3 December 2008 ; 2008 , Pages 100-105 ; 9781424424054 (ISBN) Abdolmaleki, M ; Ranjbar, A. M ; Ansarimehr, P ; Borjian Boroujeni, S ; Sharif University of Technology
    2008
    Abstract
    Load-frequency control is the intrinsic function of the governor in the power plants. It would be used in variant structures depend on the controller type such as PID, adaptive, fuzzy or robust. Temporary droop structure governor (TDSG) was commonly used in Hydro power plants (HPP). After representation of TDSG, this paper is dedicated to introducing a procedure for tuning TDSG parameters. The technique is based on pole placement for the closed loop poles of the system. These poles correspond to the TDSG parameters that by accurate tuning of them, pole placement is accomplished. The results for tuning TDSG of Abbaspour HPP have been presented as well. © 2008 IEEE  

    Stabilizing control structures: An optimization framework

    , Article IEEE Transactions on Automatic Control ; 2021 ; 00189286 (ISSN) Mosalli, H ; Babazadeh, M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    This paper presents a new optimization-based approach to determine the class of stabilizing control structures with the necessary set of feedback links for interconnected systems. The proposed approach relies on a graph theoretic interpretation and its equivalence in terms of binary linear programs (BLP). To carry out the primary goal, first, the stabilizability of an LTI system under the decentralized control structure is presented in terms of a BLP. Next, two graph-based criteria are proposed to characterize stabilizing control structures with the required feedback links. Finally, all possible stabilizing control structures with the necessary feedback links are derived via solving a set of... 

    Application of state feedback controller to ensure robust d-stable operation of virtual synchronous generators

    , Article IEEE Transactions on Energy Conversion ; Volume 36, Issue 2 , 2021 , Pages 602-610 ; 08858969 (ISSN) Pourmohammad, M ; Toulabi, M ; Ranjbar, A. M ; Sharif University of Technology
    Institute of Electrical and Electronics Engineers Inc  2021
    Abstract
    This article presents a comprehensive small signal model for a virtual synchronous generator (VSG) integrated into a microgrid. In the developed state-space, active and reactive power control loops of the VSG as well as resistances, and reactances of the lines are considered. Based on this model, the robust D-stable region in terms of different values of inertia constant $(M)$, and damping coefficient $(D)$ values of the VSG is obtained. To enhance both transient performance as well as guarantee the robust D-stable operation of VSG, an optimization problem is also proposed. Moreover, a new control method is suggested to damp frequency oscillations of the microgrid. The proposed controller is... 

    CDM-based design and performance evaluation of a robust AQM method for dynamic TCP/AQM networks

    , Article Computer Communications ; Volume 32, Issue 1 , 2009 , Pages 213-229 ; 01403664 (ISSN) Bigdeli, N ; Haeri, M ; Sharif University of Technology
    2009
    Abstract
    A new robust AQM strategy for dynamically varying TCP/AQM networks is proposed and its performance is investigated through computer simulations in MATLAB and ns-2 environments. The developed AQM is designed based on coefficient diagram method (CDM), which is a new indirect pole placement method that considers the speed, stability and robustness of the closed loop system in terms of time domain specifications. Simulation results indicate that the new method (CDM-AQM) performs very well for network variations both in topology and traffic. Besides, a new adaptive controller based on CDM as an AQM method is introduced. In the developed adaptive AQM (ACDM), the output feedback pole placement is... 

    Hardware-in-the-loop optimization of an active vibration controller in a flexible beam structure using evolutionary algorithms

    , Article Journal of Intelligent Material Systems and Structures ; Vol. 25, issue. 10 , 2014 , p. 1211-1223 Nobahari, H ; Hosseini Kordkheili, S. A ; Afshari, S. S ; Sharif University of Technology
    Abstract
    In this study, active vibration control of a cantilevered flexible beam structure equipped with bonded piezoelectric sensor/actuators is investigated. The linear quadratic regulator technique together with an observer is adopted to design the controller as well as to provide the full-state feedback. Two different approaches are subsequently used for simultaneously integrated optimization of the controller and observer parameters. In the first approach, a linear experimental model of the system is obtained using identification techniques, and the optimization is then performed based on a computer simulation of the system. However, in the second approach, a hardware-in-the-loop optimization... 

    Regulator and tracking system design for a single-rod hydraulic actuator via pole-placement approach

    , Article ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011, 11 November 2011 through 17 November 2011 ; Volume 7, Issue PARTS A AND B , November , 2011 , Pages 173-181 ; 9780791854938 (ISBN) Moradi, H ; Hajikolaei, K. H ; Bakhtiari Nejad, F ; Sharif University of Technology
    2011
    Abstract
    Due to the nonlinear dynamics of hydraulic systems, applying high performance closed-loop controllers is complicated. In this paper, a single-rod hydraulic actuator is considered in which load displacement (for positioning purposes) is controlled via manipulation of the input voltage to the servo-valve. Dynamics of the servo-valve is described by first and second order transfer functions (named as Models 1 and 2). Through linearization of the system around its operating points, dynamics of the hydraulic actuator is represented in the state space. A full-order observer is designed for on-line states estimation. Then, feedback control system is designed for both regulation and tracking... 

    Vision-based navigation in autonomous close proximity operations using neural networks

    , Article IEEE Transactions on Aerospace and Electronic Systems ; Volume 47, Issue 2 , April , 2011 , Pages 864-883 ; 00189251 (ISSN) Khansari Zadeh, S. M ; Saghafi, F ; Sharif University of Technology
    Abstract
    Tight unmanned aerial vehicle (UAV) autonomous missions such as formation flight (FF) and aerial refueling (AR) require an active controller that works in conjunction with a precise sensor that is able to identify an in-front aircraft and to estimate its relative position and orientation. Among possible choices vision sensors are of interest because they are passive in nature and do not require the cooperation of the in-front aircraft in any way. In this paper new vision-based estimation and navigation algorithms based on neural networks is developed. The accuracy and robustness of the proposed algorithm have been validated via a detailed modeling and a complete virtual environment based on...