Electrical - Electronic Engineering / Elektrik - Elektronik Mühendisliği
Permanent URI for this collectionhttps://hdl.handle.net/11147/11
Browse
10 results
Search Results
Article Citation - WoS: 4Citation - Scopus: 5An Asymptotically Stable Robust Controller Formulation for a Class of Mimo Nonlinear Systems With Uncertain Dynamics(Taylor and Francis Ltd., 2016) Bıdıklı, Barış; Tatlıcıoğlu, Enver; Zergeroğlu, Erkan; Bayrak, AlperIn this work, we present a novel continuous robust controller for a class of multi-input/multi-output nonlinear systems that contains unstructured uncertainties in their drift vectors and input matrices. The proposed controller compensates uncertainties in the system dynamics and achieves asymptotic tracking while requiring only the knowledge of the sign of the leading principal minors of the input gain matrix. A Lyapunov-based argument backed up with an integral inequality is applied to prove the asymptotic stability of the closed-loop system. Simulation results are presented to illustrate the viability of the proposed method.Conference Object Citation - WoS: 28Citation - Scopus: 34A New Robust 'integral of Sign of Error' Feedback Controller With Adaptive Compensation Gain(Institute of Electrical and Electronics Engineers Inc., 2013) Bıdıklı, Barış; Tatlıcıoğlu, Enver; Bayrak, Alper; Zergeroğlu, ErkanIn this paper, a new robust integral of signum of error (RISE) feedback type controller is designed for a class of uncertain nonlinear systems. Unlike the previous versions of RISE feedback type controllers, the proposed controller does not require prior knowledge of upper bounds of the vector containing the uncertainties of the dynamical system plus desired system dynamics (and their derivatives) for the control gain selection. The aforementioned enhancement is made possible via the design of a time-varying compensation gain as opposed to a constant gain used in previous RISE feedback type controllers. Asymptotic stability of the error signals and the boundedness of the closed-loop system signals are ensured via Lyapunov based arguments. Numerical simulation studies are presented to illustrate the viability of the proposed method. ©2013 IEEE.Conference Object Citation - Scopus: 1Robust Adaptive Control of Nonlinear Systems With Unknown State Delay(Institute of Electrical and Electronics Engineers Inc., 2013) Bayrak, Alper; Tatlıcıoğlu, Enver; Bıdıklı, Barış; Zergeroğlu, ErkanIn this work, we propose a new robust adaptive controller for a class of multi-input multi-output nonlinear systems subject to uncertain state delay. The proposed method is proven to yield semi-global asymptotic tracking despite the presence of additive input and output disturbances and parametric uncertainty in the system dynamics. An adaptive desired system compensation in conjunction with a continuous nonlinear integral feedback component is utilized in the design of the controller and Lyapunov-based techniques, are used to prove that the tracking error is asymptotically driven to zero. Numerical simulation results are presented to demonstrate the effectiveness of the proposed method. © 2013 IEEE.Article Citation - WoS: 8Citation - Scopus: 8Online Time Delay Identification and Control for General Classes of Nonlinear Systems(SAGE Publications Inc., 2013) Bayrak, Alper; Tatlıcıoğlu, EnverIn this study, online identification of state delays is discussed. First, a novel adaptive time delay identification technique is proposed for general classes of nonlinear systems subject to state delays. The stability of the time delay identification algorithm is analyzed via Lyapunov-based techniques. In this work, we consider the time delay as a nonlinear parameter effecting the system which is a seemingly novel departure from the existing literature. As an extension, this technique is modified to design a tracking controller for general classes of nonlinear systems subject to state delays. The main novelty of this controller is that identification of unknown state delays are ensured while output tracking objective is satisfied. Numerical simulations are conducted that demonstrate the efficiency of the time delay identification algorithm and the tracking controller.Conference Object Citation - WoS: 3Citation - Scopus: 6Online Time Delay Identification and Control for General Classes of Nonlinear Systems(Institute of Electrical and Electronics Engineers Inc., 2012) Bayrak, Alper; Tatlıcıoğlu, EnverIn this study, online identification of state delays is discussed. First, a novel adaptive time delay identification technique is proposed for general classes of autonomous nonlinear systems subject to state delays. As an extension, this technique is modified to design a tracking controller for general classes of nonlinear systems subject to state delays. The main novelty of this controller is that identification of unknown state delays is ensured while output tracking objective is satisfied. Extensive numerical simulations are presented that demonstrate the efficiency of the time delay identification algorithm and the tracking controller. © 2012 IEEE.Conference Object Filter-based control for parallel plate micro electrostatic actuators(Institute of Electrical and Electronics Engineers Inc., 2011) Salah, Mohammed H.; Bayrak, Alper; Tatlıcıoğlu, EnverIn this paper, a filter-based nonlinear control strategy for parallel-plate micro electrostatic actuators is designed. The proposed control technique utilizes the measurements of the micro actuator's movable plate displacement and the device internal charge. The information of the micro actuator's movable plate velocity is utilized as well in the control synthesis but since it is difficult to be measured, filtered signals are designed and utilized to facilitate the control development. A Lyapunov-based analysis is presented which proves that a desired time-varying displacement of the micro actuator's movable plate is accurately tracked. The proposed nonlinear controller is capable of controlling the movable plate beyond the pull-in boundary that is one third of the capacitive gap. Representative numerical simulations are introduced to demonstrate the performance of the proposed filter-based nonlinear control strategy in accurately tracking the deflection of the micro electrostatic movable plate within the entire capacitive gap. Finally, a comparison with a standard PID controller is also presented to demonstrate the effectiveness of the proposed control design. © 2011 IEEE.Conference Object Citation - WoS: 2Citation - Scopus: 4A novel online adaptive time delay identification technique(Institute of Electrical and Electronics Engineers Inc., 2011) Bayrak, Alper; Tatlıcıoğlu, EnverIn this study, an online time delay identification technique is proposed. Different from the relevant literature, the time delay is considered as a nonlinear parameter and nonlinear parameter estimation techniques are adopted. The stability of the adaptive update law can be guaranteed via Lyapunov based arguments and numerical simulations are conducted to demonstrate the proof of concept. © 2011 IEEE.Article Citation - WoS: 3Citation - Scopus: 3On-Line Educational Tool for the Parallel Operation of the Synchronous Generators(John Wiley and Sons Inc., 2011) Bekiroğlu, Erdal; Bayrak, AlperThis study presents a PC and a PIC microcontroller based an on-line educational tool for the monitoring and controlling of the parallel operation of the synchronous generators. The presented tool measures the voltages, the frequencies, the phase sequences, and the synchronism time data of the generators through microcontroller. The measured data, the voltage graphics, and the status of the parallel operation conditions are monitored on the computer instantaneously. The parallel operation of the generators is controlled with the developed tool automatically. The educational tool is user-friendly, real-time, reliable, and precise. © 2009 Wiley Periodicals, Inc.Conference Object Citation - WoS: 5Citation - Scopus: 16Automatic Synchronization Unit for the Parallel Operation of Synchronous Generators(Institute of Electrical and Electronics Engineers Inc., 2009) Bekiroğlu, Erdal; Bayrak, AlperIn this study, an automatic synchronization unit has been developed for the parallel connection of synchronous generators. Two synchronous generators are connected in parallel automatically with the developed control unit. Synchronous generators are also connected in parallel with the line. The voltages, frequencies, phase sequences and synchronism time data have been transferred to the microcontroller. These data are monitored and evaluated by the control algorithm coded into the microcontroller. Parallel operation of generators are realized automatically when all parallel connection conditions are occur. The system doesn't require additional measuring tools for monitoring and control processes. The developed automatic synchronization unit is fast, cost effective, reliable and precise to be used for monitoring, measurement and parallel operation of the synchronous generators.Article Citation - WoS: 10Citation - Scopus: 11A novel online adaptive time delay identification technique(Taylor and Francis Ltd., 2016) Bayrak, Alper; Tatlıcıoğlu, EnverTime delay is a phenomenon which is common in signal processing, communication, control applications, etc. The special feature of time delay that makes it attractive is that it is a commonly faced problem in many systems. A literature search on time-delay identification highlights the fact that most studies focused on numerical solutions. In this study, a novel online adaptive time-delay identification technique is proposed. This technique is based on an adaptive update law through a minimum-maximum strategy which is firstly applied to time-delay identification. In the design of the adaptive identification law, Lyapunov-based stability analysis techniques are utilised. Several numerical simulations were conducted with Matlab/Simulink to evaluate the performance of the proposed technique. It is numerically demonstrated that the proposed technique works efficiently in identifying both constant and disturbed time delays, and is also robust to measurement noise.