WoS İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/394

Browse

Now showing 1 - 12 of 12

Citation - WoS: 7
Citation - Scopus: 11
Chaotic Map Construction From Common Nonlinearities and Microcontroller Implementations
(World Scientific Publ Co Pte Ltd, 2016) Ablay, Gunyaz
This work presents novel discrete-time chaotic systems with some known physical system non-linearities. Dynamic behaviors of the models are examined with numerical methods and Arduino microcontroller-based experimental studies. Many new chaotic maps are generated in the form of x(k + 1) = rx(k) + f(x(k)) and high-dimensional chaotic systems are obtained by weak coupling or cross-coupling the same or different chaotic maps. An application of the chaotic maps is realized with Arduino for chaotic pulse width modulation to drive electrical machines. It is expected that the new chaotic maps and their microcontroller implementations will facilitate practical chaos-based applications in different fields.
Citation - WoS: 9
Citation - Scopus: 10
Coefficient Ratios-Based Robust Sliding Surface and Integral Sliding Mode Control Designs With Optimal Transient Responses
(Inst Engineering Technology-IET, 2014) Ablay, Gunyaz
A coefficient ratio-based sliding surface algorithm and an integral sliding mode control approach are proposed for multivariable dynamical systems. The sliding surface design problem is reduced to the specification of the desired time constant of closed-loop systems. The proposed scheme is able to accomplish a non-overshoot transient response and a short settling time for multivariable systems. The resulting sliding surfaces are robust and optimal in the existence of parameter perturbations. An integral sliding mode control approach is also developed for robust tracking by using the coefficient ratio-based robust sliding surface designs. The developed methods are implemented on a flexible robotic manipulator and a strike aircraft system, and the numerical simulation results are provided in order to show the validity and feasibility of the methods.
Citation - WoS: 1
Citation - Scopus: 1
A Generalized PID Controller for High-Order Dynamical Systems
(Slovak Univ Technology, 2021) Ablay, Gunyaz
This paper introduces a generalized PID type controller for controlling high-order dynamical systems. An optimal generalized PID control design method is developed to provide a simplified high-order output feedback control design procedure and tunable response characteristics. The controller design procedure is reduced to the specification of the desired natural frequency and the solution of a polynomial equation. The control method is capable of providing a desired control performance under set-point and disturbance variations. The performance of the proposed control method is implemented on some unstable and nonlinear mechatronic systems to illustrate the robustness, effectiveness and feasibility of the method.
Citation - WoS: 1
Citation - Scopus: 2
Model-Free Controller Designs for a Magnetic Micromanipulator
(ASME, 2021) Ablay, Gunyaz
An optimal model-free controller and a linear controller are designed and applied to a horizontal magnetic micromanipulator for controlling microparticles in a liquid environment. An input-output relation based model for the magnetic micromanipulator is obtained, verified, and used in the analysis of controllers. A model-free linear controller is designed using the offset current approach. An optimal nonlinear controller based on Karush-Kuhn-Tucker conditions is designed and then modified to produce smooth control signals. Experimental results are provided to show the efficiency and feasibility of the proposed controllers. The model-free controllers yield short settling time and zero steady-state error in the control of magnetic microparticles.
Citation - WoS: 40
Citation - Scopus: 46
A Modeling and Control Approach to Advanced Nuclear Power Plants With Gas Turbines
(Pergamon-Elsevier Science Ltd, 2013) Ablay, Gunyaz
Advanced nuclear power plants are currently being proposed with a number of various designs. However, there is a lack of modeling and control strategies to deal with load following operations. This research investigates a possible modeling approach and Load following control strategy for gas turbine nuclear power plants in order to provide an assessment way to the concept designs. A load frequency control strategy and average temperature control mechanism are studied to get load following nuclear power plants. The suitability of the control strategies and concept designs are assessed through linear stability analysis methods. Numerical results are presented on an advanced molten salt reactor concept as an example nuclear power plant system to demonstrate the validity and effectiveness of the proposed modeling and load following control strategies. (C) 2013 Elsevier Ltd. All rights reserved.
Citation - WoS: 22
Citation - Scopus: 24
Novel Chaotic Delay Systems and Electronic Circuit Solutions
(Springer, 2015) Ablay, Gunyaz
Chaotic delay systems are abundant in nature and play a significant role in engineering applications and in describing global behaviors of physical systems. This work presents novel first-order chaotic delay systems with the simplest nonlinearities. The exponential, absolute value, and hyperbolic and signum functions, which arise in many systems like electronic circuits, are utilized to generate chaotic delay systems. The practical realization of chaotic delay systems is carried out with all-pass filters and diode-based electronic circuits. Bifurcation diagrams using numerical simulations and experimental results are provided to verify the existence and feasibility of the novel chaotic delay systems. It is expected that the novel chaotic delay systems and the novel electronic implementation circuits will contribute to some practical applications and modeling of physical systems or events in different fields.
Citation - WoS: 22
Citation - Scopus: 24
Online Condition Monitoring of Battery Systems With a Nonlinear Estimator
(IEEE-Inst Electrical Electronics Engineers Inc, 2014) Ablay, Gunyaz
The performance of batteries as uninterruptable power sources in any industry cannot be taken for granted. The failures in battery systems of safety-related electric systems can lead to performance deterioration, costly replacement, and, more importantly, serious hazards. The possible failures in battery systems are currently determined through periodic maintenance activities. However, it is desirable to be able to detect the underlying degradation and to predict the level of unsatisfactory performance by an online real-time monitoring system to prevent unexpected failures through early fault diagnosis. Such an online fault diagnosis method can also contribute to better maintenance and optimal battery replacement programs. A robust nonlinear estimator-based online condition monitoring method is proposed to determine the state of health of the battery systems online in industry. Real-world experimental data of a modern battery system are used to assess the efficiency of the proposed approach in the existence of parameter uncertainties.
Citation - WoS: 10
Citation - Scopus: 13
A Robust Estimator-Based Optimal Algebraic Approach to Steam Generator Feedwater Control System
(Tubitak Scientific & Technological Research Council Turkey, 2016) Ablay, Gunyaz
Feedwater control systems are used to maintain the steam generator water level within prescribed narrow limits and to provide constant supply of steam during power demand variations. Current feedwater control systems are often found to be unsatisfactory during startup and low power operations. A robust nonlinear estimator-based optimal algebraic control is developed for feedwater control systems to solve the water level tracking problem during power demand variations. It is shown that the proposed control provides an optimal and robust water level tracking with a single automatic controller over the complete range of power operations in the presence of plant uncertainties and noisy measurements.
Citation - WoS: 7
Citation - Scopus: 11
Robust Estimator-Based Optimal Control Designs for U-Tube Steam Generators
(Sage Publications Ltd, 2015) Ablay, Gunyaz; Hamamci, Serdar
U-tube steam generator level control systems are used to maintain the water level within prescribed narrow limits and to provide constant supply of high-quality steam during power demand variations. Traditional level control systems are often found to be unsatisfactory during low power operations and start-up conditions. Robust non-linear estimator-based optimal control systems are proposed for steam generator level control systems to solve the water level tracking problem during power (or steam) demand variations. It is shown that the proposed control strategies provide optimal and robust water level tracking with a single controller over the complete range of power operation with model and parameter uncertainties and noisy measurements.
Citation - WoS: 2
Citation - Scopus: 1
Robust Integral Controllers for High-Order Class-D Power Amplifiers
(Inst Engineering Technology-IET, 2018) Ablay, Gunyaz
This study presents variable structure system theory based robust integral controllers for class-D power amplifiers. These amplifiers are highly efficient switching type power amplifiers with negligible losses. Sensorless and current feedback based integral controllers with sliding modes are designed to provide robust tracking performance with negligible phase delays and distortions. The methods are capable of providing high-quality outputs by maximising gain and minimising the tracking error and phase shifts. The validity, feasibility and robustness performance of the controllers are investigated through circuit realisations.
Citation - WoS: 3
Citation - Scopus: 3
Robust Reactivity, Neutron Source, and Precursor Estimators for Nuclear Reactors
(Elsevier Science SA, 2013) Ablay, Gunyaz
Reactivity, precursor concentration, and external neutron source strength determine control, operation and performance of nuclear reactors. These main reactor quantities are not directly measurable and must be calculated or estimated using reactor kinetics. This study presents efficient and robust nonlinear estimation algorithms for predicting these fundamental reactor quantities. The effectiveness of the proposed estimators is assessed through chirp and step test signals in the presence of parameter uncertainties and measurement noise. (C) 2013 Elsevier B.V. All rights reserved.
Citation - WoS: 23
Citation - Scopus: 32
Variable Structure Controllers for Unstable Processes
(Elsevier Sci Ltd, 2015) Ablay, Gunyaz
A variable structure control (VSC) method for unstable industrial processes is proposed. The proposed control method is able to provide a highly satisfactory system performance and to tackle with robustness issues of the processes in the presence of uncertainties. An ITAE-based numerical tuning algorithm for acquiring optimal control parameters, and a direct auto-tuning mechanism for the proposed controller are also provided. The performance of the proposed VSC method is illustrated on some unstable process models including a continuous stirred tank reactor (CSTR), in order to show its effectiveness, validity and feasibility. (C) 2015 Elsevier Ltd. All rights reserved.

Browse

Browsing WoS İndeksli Yayınlar Koleksiyonu by Institution Author "Ablay, Gunyaz"