Profile URL: https://hdl.handle.net/20.500.12573/5640
Main Affiliation:01. Abdullah Gül University
Status: Former Staff
Name Variants:
Ablay, Günyaz Ablay, Gunyaz
39 results
Scholarly Output Search Results
Now showing 1 - 10 of 39
Conference Object Citation - Scopus: 1Modeling and Simulation of Advanced Nuclear Reactors(IEEE Computer Society help@computer.org, 2013-11) Ablay, GünyazAdvanced 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 for advanced nuclear power plants in order to provide an assessment way to the concept designs. The modeling approach covers linear and nonlinear reactor modeling and linear modeling of heat exchanger-turbine- generator systems. Numerical results are presented on an example molten-salt type nuclear power plant system to demonstrate the validity and effectiveness of the modeling approach. © 2013 IEEE. © 2014 Elsevier B.V., All rights reserved.Conference Object Citation - WoS: 1Citation - Scopus: 2Steam Generator Level Control With an Observer-Based Algebraic Approach(IEEE Computer Society help@computer.org, 2013-11) Ablay, GünyazLevel control systems are used to maintain the steam generator water level within the prescribed narrow limits and to provide constant supply of steam during power demand variations. The current level 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 level 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 operation in the presence of plant uncertainties and noisy measurements. © 2013 The Chamber of Turkish Electrical Engineers-Bursa. © 2020 Elsevier B.V., All rights reserved.Article Citation - WoS: 23Citation - Scopus: 25Online Condition Monitoring of Battery Systems With a Nonlinear Estimator(IEEE-Inst Electrical Electronics Engineers Inc, 2014-03) Ablay, GunyazThe 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.Article Citation - WoS: 27Citation - Scopus: 32Cascade Sliding Mode-Based Robust Tracking Control of a Magnetic Levitation System(Sage Publications Ltd, 2016-08-05) Eroglu, Yakup; Ablay, GunyazMagnetic levitation systems are able to provide frictionless, reliable, fast and economical operations in wide-range applications. The effectiveness and applicability of these systems require precise feedback control designs because the magnetic levitation is an unstable process and have highly nonlinear dynamics. In this article, a robust sliding mode-based cascade control approach is proposed for effectively tracking the reference position of a magnetic levitation system. The magnetic levitation plant is described with electrical and mechanical models, and the control problems of these parts are treated with cascade controllers. An integral sliding mode and an output feedback sliding mode controllers are designed for use in the cascade loops. The performance of the sliding mode controllers is compared with a proportional-integral-velocity plus proportional-integral control structure. It is shown that the proposed control structure is able to provide a highly satisfactory tracking performance and can eliminate the effects of the inductance-related uncertainties and operating point originated disturbances. The experimental results are provided to validate the efficacy and feasibility of the approach.Article Citation - WoS: 3Citation - Scopus: 3Robust Reactivity, Neutron Source, and Precursor Estimators for Nuclear Reactors(Elsevier Science SA, 2013-12) Ablay, GunyazReactivity, 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.Conference Object Citation - WoS: 2Citation - Scopus: 2PI-V plus Sliding Mode Based Cascade Control of Magnetic Levitation(Institute of Electrical and Electronics Engineers Inc., 2015-11) Eroǧlu, Yakup; Ablay, GünyazMagnetic levitation systems are able to provide frictionless, reliable, fast and economical operations in wide-range applications. The effectiveness and applicability of these systems require precise feedback control design. The position control problem of the magnetic levitation can be solved with robust current control approaches. A cascade control approach consisting of PI-velocity plus sliding mode control (PI-V plus SMC) is designed to render high control performance and robustness to the magnetic levitation. It will be shown that the SMC designed for electrical part of the plant (current controller) is able to eliminate the effects of the inductance related uncertainties of the electromagnetic coil of the plant. Experimental results are provided to validate the efficacy of the approach. © 2016 Elsevier B.V., All rights reserved.Master Thesis Micro Manyetik ve Parçacıklarının Manipülasyonuna Yönelik Sistem Tasarımı(Abdullah Gül Üniversitesi, 2018) BÖYÜK, MUSTAFA; Böyük, Mustafa; İçöz, Kutay; Ablay, GünyazManyetik cımbızlar çeşitli uygulamalar ve ölçümler için hücreleri veya biyomolekülleri manipüle edebilir. Tek moleküllü manipülasyonlar için bir elektromanyetik mikro manipülatör tasarlandı, modellendi ve kontrol edildi. Elektromanyetik cımbız mikron boyutlu süperparamanyetik parçacıkları uygun kontrol mekanizması yardımıyla kontrol edebilir. Bu parçacıklar, hedef biyomoleküllerin yakalanması için reseptörler ile fonksiyonel hale getirilebildiğinden dolayı yüklü partiküller harici bir manyetik alan kullanılarak belirli bir yere taşınabilirler. Manyetik tek kutup ve manyetik devre yaklaşımları, manyetik sistemin dinamik denklemini modellemek için bu çalışmada kullanıldı. Ofset akım tabanlı geri besleme ile doğrusallaştırma yaklaşımı bir kontrolör tasarlanarak, sıfır kararlı-durum hatasıyla geniş çalışma koşulları sağlandı. Tek parçacığın konumunu bulmak için görüntü tabanlı algoritma geliştirilmiştir. Türetilmiş model ve kontrol sistemini doğrulamak için sayısal simülasyonlar yapılır. Tasarlanan manyetik sistem, 1 ila 10 mikrometre çapındaki manyetik bir parçacığı 1 amperden az bir akımla kontrol etmek için 1-100 pN arasında kuvvet uygulayabilmektedir. Manyetik yönlendirici sistemi, tek hücre ayrımı, ve biyosensör gelişmeleri için kullanılabilir.Article Citation - WoS: 5Citation - Scopus: 6Design, Modeling, and Control of a Horizontal Magnetic Micromanipulator(Sage Publications Ltd, 2019-01-31) Ablay, Gunyaz; Boyuk, Mustafa; Icoz, KutayMagnetic micromanipulators with a wide range of force generating capabilities are able to manipulate micron size particles for various applications and measurements. These magnetic particles can be coated with receptors to specifically bind to target biomolecules. In this work, a horizontal magnetic micromanipulator is designed, modeled and controlled for single micron size magnetic particle manipulations. A method is presented for dynamic modeling of magnetic micromanipulators. A feedback control method is designed that allows direct linearization of the system. It is shown that the proposed controller guarantees the stability of the closed-loop system, and yields zero steady-state error in a wide range of operation conditions. We show that the micromanipulator is able to generate a wide range of piconewton (pN) scale forces on a superparamagnetic particle for single molecule separation, and biosensor developments.Article Citation - WoS: 1Citation - Scopus: 2Design and Real-Time Implementation of a Sliding Mode Observer Utilizing Voltage Signal Injection and PLL for Sensorless Control of IPMSMs(Elsevier - Division Reed Elsevier India Pvt Ltd, 2024-11) Ates, Ertugrul; Tekgun, Burak; Ablay, Gunyaz; Barut, MuratIn this study, a sliding mode observer (SMO) based on high-frequency (HF) voltage signal injection and a phase-locked loop (PLL) is proposed for estimating the extended electromotive force (EEMF), rotor position, and rotor velocity of an interior permanent magnet synchronous machine (IPMSM). This approach addresses real-time estimation challenges associated with standard SMO and PLL at very low speeds and standstill. A reliable and accurate sensorless speed control system for IPMSM is then developed and implemented in real time using the proposed SMO and PLL, covering a wide range of speeds, including low-speed and standstill conditions. The SMO effectively estimates the EEMF, while the PLL extracts the rotor velocity and position based on these estimates. Compared to conventional SMO and PLL methods, real-time results from an 8-pole, 0.4 kW IPMSM demonstrate the superior efficiency of the proposed system.Article Citation - WoS: 3Citation - Scopus: 5Feedback Controller Designs for an Electromagnetic Micromanipulator(Sage Publications Ltd, 2019-09-09) Boyuk, Mustafa; Eroglu, Yakup; Ablay, Gunyaz; Icoz, KutayMagnetic micromanipulators are capable of generating wide range of magnetic forces to manipulate magnetic microparticles for biomedical applications. In this study, a multipole magnetic micromanipulator system including electromagnets, driver circuitry and control unit is designed, modeled and implemented. The micromanipulator can produce a broad range of magnetic forces up to 25 pN on a single magnetic microparticle (1-10 mu m diameter) that is 5 mm away from the electromagnet core tip. Both linear and nonlinear controllers are designed and implemented, and the proposed nonlinear controller produces smooth control currents to assure closed-loop stability of the system with 1 s non-overshoot transient response and zero steady-state tracking error. The maximum output current of the driver circuitry is set to 1 A. The single particle at the center is moved at a speed of 5 mm/s. The fully automatic system can be utilized in applications related to single cell or microparticle manipulations.