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Articles 2641 - 2670 of 3106
Full-Text Articles in Engineering
Low-Complexity Channel Estimation For Ofdm Systems In High-Mobility Fading Channels, Mahmut Yalçin, Aydin Akan, Hakan Doğan
Low-Complexity Channel Estimation For Ofdm Systems In High-Mobility Fading Channels, Mahmut Yalçin, Aydin Akan, Hakan Doğan
Turkish Journal of Electrical Engineering and Computer Sciences
Nowadays, multicarrier transmission is very popular because of the high data rate requirement of wireless systems. Orthogonal frequency-division multiplexing (OFDM) is a special case of multicarrier transmission. It is considered an effective technique for frequency-selective channels because of its spectral efficiency, its robustness in different multipath propagation environments, and its ability of combating intersymbol interference. Losing subchannel orthogonality causes interchannel interference, but many conventional channel estimators assume that the channel is time-invariant during one OFDM symbol. This assumption causes error floors along the OFDM symbol for high-mobility cases. In this paper, we propose 2-dimensional pilot symbol-assisted channel estimation for wireless …
Optimization And Coordination Of Svc-Based Supplementary Controllers And Psss To Improve Power System Stability Using A Genetic Algorithm, Ali Darvish Falehi, Mehrdad Rostami, Aref Doroudi, Abdolaziz Ashrafian
Optimization And Coordination Of Svc-Based Supplementary Controllers And Psss To Improve Power System Stability Using A Genetic Algorithm, Ali Darvish Falehi, Mehrdad Rostami, Aref Doroudi, Abdolaziz Ashrafian
Turkish Journal of Electrical Engineering and Computer Sciences
In this piaper, a lead-lag structure is proposed as a main damping controller for a static VAR compensator (SVC) to diminish power system oscillations. To confirm the transient performance of the proposed controller, it was compared to a proportional integral derivative (PID) damping controller. Power system stability improvement was thoroughly examined using these supplementary damping controllers as well as a power system stabilizer i(PSS). The generic algorithm (GA) is well liked in the academic environment due to its immediate perceptiveness, ease of performance, and ability to impressively solve highly nonlinear objectives. Thus, the GA optimization technique was applied to solve …
Improvement Of Smart Card Based Password Authentication Scheme For Multiserver Environments, Zuowen Tan
Improvement Of Smart Card Based Password Authentication Scheme For Multiserver Environments, Zuowen Tan
Turkish Journal of Electrical Engineering and Computer Sciences
In multiserver (MS) environments, it is preferable for a remote user to login to different service provider servers by keying in the same password. Recently, Wang et al. proposed an improvement on the dynamic identity-based smart card authentication scheme of Liao and Wang for MS environments. Sandeep et al. improved the dynamic identity-based smart card authentication scheme of Hsiang et al. for MS architecture. However, we found that the schemes of Wang et al. and Sandeep et al. failed to provide service provider server authentication, perfect forward security, and login scalability. In addition, the scheme of Sandeep et al. was …
Hybrid Feature Selection For Text Classification, Serkan Günal
Hybrid Feature Selection For Text Classification, Serkan Günal
Turkish Journal of Electrical Engineering and Computer Sciences
Feature selection is vital in the field of pattern classification due to accuracy and processing time considerations. The selection of proper features is of greater importance when the initial feature set is considerably large. Text classification is a typical example of this situation, where the size of the initial feature set may reach to hundreds or even thousands. There are numerous research studies in the literature offering different feature selection strategies for text classification, mostly focused on filters. In spite of the extensive number of these studies, there is no significant work investigating the efficacy of a combination of features, …
Short-Term Wind Speed Estimation Based On Weather Data, Okan Özgönenel, David W.P. Thomas
Short-Term Wind Speed Estimation Based On Weather Data, Okan Özgönenel, David W.P. Thomas
Turkish Journal of Electrical Engineering and Computer Sciences
For accurate and efficient use of wind power, it is important to know the statistical characteristics, availability, diurnal variation, and prediction of wind speed. Prediction of wind power permits the scheduling of the connection or the disconnection of wind turbines to achieve optimal operating costs. In this paper, a simple and accurate method for predicting wind speed based on weather-sensitive data is presented. The proposed wind speed prediction system is cost-effective and only needs wind speed data at 40 m and weather data to forecast wind speeds at 50 m and 60 m for the current and next months. Hellman …
Multiobjective Fet Modeling Using Particle Swarm Optimization Based On Scattering Parameters With Pareto Optimal Analysis, Fi̇li̇z Güneş, Ufuk Özkaya
Multiobjective Fet Modeling Using Particle Swarm Optimization Based On Scattering Parameters With Pareto Optimal Analysis, Fi̇li̇z Güneş, Ufuk Özkaya
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, design-oriented field effect transistor (FET) models are produced. For this purpose, FET modeling is put forward as a constrained, multiobjective optimization problem. Two novel methods for multiobjective optimization are employed: particle swarm optimization (PSO) uses the single-objective function, which gathers all of the objectives as aggregating functions; and the nondominated sorting genetic algorithm-II (NSGA-II) sorts all of the trade-off solutions on the Pareto frontiers. The PSO solution is compared with the Pareto optimum solutions in the biobjective plane and the success of the first method is verified. Furthermore, the resulting FET models are compared with similar FET …
A Novel Three-Phase Transformer Hysteresis Model In Matlab^{Tm} Simulink, Okan Özgönenel, Kami̇l Ri̇fat İrfan Güney, Ömer Usta, Hasan Di̇ri̇k
A Novel Three-Phase Transformer Hysteresis Model In Matlab^{Tm} Simulink, Okan Özgönenel, Kami̇l Ri̇fat İrfan Güney, Ömer Usta, Hasan Di̇ri̇k
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a new transformer model displaying hysteresis using the MATLAB{\texttrademark} Simulink environment. The proposed model displays a complete scheme for the simulation of 3-phase transformers. The new model is mainly based on the transmission line model and the Jiles-Atherton model of a power system using lumped parameters. Jiles-Atherton model parameters were determined by curve fitting and numerical optimization iteration. The developed model is particularly suitable for fault analysis and protective relaying studies under harmonic conditions where the transformer is driven into the nonlinear regime. The performance of the method was evaluated by both theorical and experimental data.
Circuit Model And Parasitic Parameter Extraction Of The Spark Plug In The Ignition System, Quandi Wang, Yali Zheng, Jihui Yu, Jin Jia
Circuit Model And Parasitic Parameter Extraction Of The Spark Plug In The Ignition System, Quandi Wang, Yali Zheng, Jihui Yu, Jin Jia
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a circuit model of the spark plug in the ignition system for conducted electromagnetic interference (EMI). Based on the spark plug's current discharge channel, the circuit model of the spark plug is established with the parasitic parameters and the air-gap model. The parasitic parameters of the spark plug are extracted with the finite element method, and the air-gap model of the spark plug is analyzed using the electric circuit principles and the air-discharge theory. The simulation and measurement results validate this model. Furthermore, this model confirms that the spark plug discharge is the main conducted EMI source …
Stability Of The Adaptive Fading Extended Kalman Filter With The Matrix Forgetting Factor, Cenker Bi̇çer, Esi̇n Köksal Babacan, Levent Özbek
Stability Of The Adaptive Fading Extended Kalman Filter With The Matrix Forgetting Factor, Cenker Bi̇çer, Esi̇n Köksal Babacan, Levent Özbek
Turkish Journal of Electrical Engineering and Computer Sciences
The extended Kalman filter is extensively used in nonlinear state estimation problems. As long as the system characteristics are correctly known, the extended Kalman filter gives the best performance. However, when the system information is partially known or incorrect, the extended Kalman filter may diverge or give biased estimates. An extensive number of works has been published to improve the performance of the extended Kalman filter. Many researchers have proposed the introduction of a forgetting factor, both into the Kalman filter and the extended Kalman filter, to improve the performance. However, there are 2 fundamental problems with this approach: the …
Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar
Optimization Of Pilot Tones Using Differential Evolution Algorithm In Mimo-Ofdm Systems, Muhammet Nuri̇ Seyman, Necmi̇ Taşpinar
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we propose a differential evolution (DE) algorithm for optimizing the placement and power of the pilot tones that are utilized by a least square (LS) algorithm for channel estimation in multiple-input and multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) systems. Computer simulations demonstrated that the performance of the LS algorithm was increased by optimizing the pilot tones with the DE algorithm instead of locating them orthogonally. We used the upper bound of the mean square error (MSE) as a fitness function of the DE algorithm for optimization tasks. With the use of an upper bound, it is not necessary …
An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab
An Improved Fastslam Framework Using Soft Computing, Ramazan Havangi, Mohammad Ali Nekoui, Mohammad Teshnehlab
Turkish Journal of Electrical Engineering and Computer Sciences
FastSLAM is a framework for simultaneous localization and mapping (SLAM) using a Rao-Blackwellized particle filter. However, FastSLAM degenerates over time. This degeneracy is due to the fact that a particle set estimating the pose of the robot loses its diversity. One of the main reasons for losing particle diversity in FastSLAM is sample impoverishment. In this case, most of the particle weights are insignificant. Another problem of FastSLAM relates to the design of an extended Kalman filter (EKF) for the landmark position's estimation. The performance of the EKF and the quality of the estimation depend heavily on correct a priori …
Action-Reaction Based Parameters Identification And States Estimation Of Flexible Systems, Islam Shoukry, Emrah Deni̇z Kunt, Asif Sabanovic
Action-Reaction Based Parameters Identification And States Estimation Of Flexible Systems, Islam Shoukry, Emrah Deni̇z Kunt, Asif Sabanovic
Turkish Journal of Electrical Engineering and Computer Sciences
This work attempts to identify and estimate flexible system's parameters and states by a simple utilization of the Action-Reaction law of dynamical systems. Attached actuator to a dynamical system or environmental interaction imposes an action that is instantaneously followed by a dynamical system reaction. The dynamical system's reaction carries full information about the dynamical system including system parameters, dynamics and externally applied forces that arise due to system interaction with the environment. This in turn implies that the dynamical system's reaction can be considered as a natural feedback as it carries full coupled information about the dynamical system. The idea …
Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay
Ttradeoff Tables For Compression Functions: How To Invert Hash Values Radeoff Tables For Compression Functions: How To Invert Hash Values, Orhun Kara, Adem Atalay
Turkish Journal of Electrical Engineering and Computer Sciences
Hash functions are one of the ubiquitous cryptographic functions used widely for various applications such as digital signatures, data integrity, authentication protocols, MAC algorithms, RNGs, etc. Hash functions are supposed to be one-way, i.e., preimage resistant. One interesting property of hash functions is that they process arbitrary-length messages into fixed-length outputs. In general, this can be achieved mostly by applying compression functions onto the message blocks of fixed length, recursively. The length of the message is incorporated as padding in the last block prior to the hash, a procedure called the Merkle-Damgard strengthening. In this paper, we introduce a new …
Reducing Electromagnetic Interferences In Flyback Ac-Dc Converters Based On The Frequency Modulation Technique, Gökhan Çabuk, Selçuk Kilinç
Reducing Electromagnetic Interferences In Flyback Ac-Dc Converters Based On The Frequency Modulation Technique, Gökhan Çabuk, Selçuk Kilinç
Turkish Journal of Electrical Engineering and Computer Sciences
One of the most preferable types of switched-mode power supplies (SMPS) is the flyback converter, due to its wide range of application areas. Properties such as low cost, provision of multiple output voltage terminals, and higher efficiencies make it important, and hence its usage in technologies including cell phone chargers, personal computers, set-top boxes, and televisions is increasing. Special attention should be paid to the design of this type of converter due to its working principles and electromagnetic interference (EMI) performance. Rapid switching of high current and high voltage during the operation of SMPS causes an EMI problem. The level …
A Robust Adaptive Fuzzy Control Of A Unified Power Flow Controller, Sebaa Morsli, Allaoui Tayeb, Denai Mouloud, Chaker Abdelkader
A Robust Adaptive Fuzzy Control Of A Unified Power Flow Controller, Sebaa Morsli, Allaoui Tayeb, Denai Mouloud, Chaker Abdelkader
Turkish Journal of Electrical Engineering and Computer Sciences
This paper investigates the control of a unified power flow controller (UPFC) to improve the stability of a power system, hence providing security under increased power flow conditions. The proposed control methods include a direct proportional and integral (PI) controller and an adaptive fuzzy logic controller (AFLC). The performances of these controllers were evaluated under different operating conditions of the power system and the results demonstrated that PI and AFLC are very effective in improving the transient power system stability and very robust against variable transmission line parameters.
Lyapunov's Direct Method For Stabilization Of The Furuta Pendulum, Türker Türker, Haluk Görgün, Gali̇p Cansever
Lyapunov's Direct Method For Stabilization Of The Furuta Pendulum, Türker Türker, Haluk Görgün, Gali̇p Cansever
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a novel stabilization result for the Furuta pendulum for a large region of attraction including almost all of the upper half plane. The solution is obtained via constructing a Lyapunov function after set of coordinate changes. Then, a set of differential equations are solved to achieve asymptotic stability which is proved in accordance with La Salle's invariance principle. The effectiveness of the proposed stabilization method is illustrated with simulation studies.
Energy Savings In Simultaneous Multi-Threaded Processors Through Dynamic Resizing Of Datapath Resources, Gürhan Küçük, Mi̇ne Mesta
Energy Savings In Simultaneous Multi-Threaded Processors Through Dynamic Resizing Of Datapath Resources, Gürhan Küçük, Mi̇ne Mesta
Turkish Journal of Electrical Engineering and Computer Sciences
Nowadays, all the designers of systems from high-performance servers to battery-operated handheld devices aim for reliability, high-performance and longevity. Central within these aims the issue of processor power consumption is becoming increasingly important. In this study, we aim to adapt our already-proven method for single-threaded superscalar processors to simultaneous multi-threaded (SMT) processors for energy savings. The original method focused on resizing datapath resources according to the demands of running applications. To achieve this, the targeted resources are physically divided into multiple partitions, and turned on and off according to the needs of the applications. Since, the energy consumption of the …
Mathematical Modeling And Vertical Flight Control Of A Tilt-Wing Uav, Kaan Taha Öner, Ertuğrul Çeti̇nsoy, Efe Sirimoğlu, Cevdet Hançer, Mustafa Ünel, Mahmut Faruk Akşi̇t, Kayhan Gülez, İlyas Kandemi̇r
Mathematical Modeling And Vertical Flight Control Of A Tilt-Wing Uav, Kaan Taha Öner, Ertuğrul Çeti̇nsoy, Efe Sirimoğlu, Cevdet Hançer, Mustafa Ünel, Mahmut Faruk Akşi̇t, Kayhan Gülez, İlyas Kandemi̇r
Turkish Journal of Electrical Engineering and Computer Sciences
This paper presents a mathematical model and vertical flight control algorithms for a new tilt-wing unmanned aerial vehicle (UAV). The vehicle is capable of vertical take-off and landing (VTOL). Due to its tilt-wing structure, it can also fly horizontally. The mathematical model of the vehicle is obtained using Newton-Euler formulation. A gravity compensated PID controller is designed for altitude control, and three PID controllers are designed for attitude stabilization of the vehicle. Performances of these controllers are found to be quite satisfactory as demonstrated by indoor and outdoor flight experiments.
A Comparative Study Of Blind And Nonblind Trainings In A Single-Carrier Wimax (Ieee 802.16-2004) Radio, Ali̇ Özen
Turkish Journal of Electrical Engineering and Computer Sciences
Experimental and theoretical bit error rate performance evaluations of blind and nonblind training techniques are obtained by using a single-carrier WiMAX (IEEE 802.16-2004) radio for high-order quadrature amplitude modulation channels. Instead of using a certain type of channel profile, this study concentrates on true frequency-selective Rayleigh fading channels and also evaluates the fast fading scenario of Rayleigh channels in a real-time WiMAX radio environment around 3.5 GHz. The popular least mean squares (LMS) learning algorithm and constant modulus learning algorithm (CMA) are used as benchmarks in an investigation of nonblind and blind trainings, namely recursive least squares (RLS), modified-CMA, normalized-CMA, …
Load Sharing Based On Moving Roles In Multiagent Systems, Şebnem Bora, Ali̇ Murat Ti̇ryaki̇, Oğuz Di̇kenelli̇
Load Sharing Based On Moving Roles In Multiagent Systems, Şebnem Bora, Ali̇ Murat Ti̇ryaki̇, Oğuz Di̇kenelli̇
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, we present a load-sharing approach based on the refactoring of agents. According to our approach, the role(s) that makes an agent overloaded is identified and transferred to less loaded agents. The excess workload of this heavily loaded agent is then transferred to the new agent. This approach defines a new agent, called the ``monitor agent,'' which monitors the workload of agents in the organization and decides about the refactoring of the agents. The monitor agent uses the platform ontology, which explicitly describes the components of the agent organization, including agents and their roles, plans, and workloads. This …
Fuzzy Logic Control For A Wind/Battery Renewable Energy Production System, Onur Özdal Mengi̇, İsmai̇l Hakki Altaş
Fuzzy Logic Control For A Wind/Battery Renewable Energy Production System, Onur Özdal Mengi̇, İsmai̇l Hakki Altaş
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, a designed proportional-integral (PI) controller and a fuzzy logic controller (FLC) that fix the voltage amplitude to a constant value of 380 V and 50 Hz for loads supplied from a wind/battery hybrid energy system are explained and compared. The quality of the power produced by the wind turbine is affected by the continuous and unpredictable variations of the wind speed. Therefore, voltage-stabilizing controllers must be integrated into the system in order to keep the voltage magnitude and frequency constant at the load terminals, which requires constant voltage and frequency. A fuzzy logic-based controller to be used …
Training Data Optimization For Anns Using Genetic Algorithms To Enhance Mppt Efficiency Of A Stand-Alone Pv System, Ahmet Afşi̇n Kulaksiz, Ramazan Akkaya
Training Data Optimization For Anns Using Genetic Algorithms To Enhance Mppt Efficiency Of A Stand-Alone Pv System, Ahmet Afşi̇n Kulaksiz, Ramazan Akkaya
Turkish Journal of Electrical Engineering and Computer Sciences
Maximum power point tracking (MPPT) algorithms are used to force photovoltaic (PV) modules to operate at their maximum power points for all environmental conditions. In artificial neural network (ANN)-based algorithms, the maximum power points are acquired by designing ANN models for PV modules. However, the parameters of PV modules are not always provided by the manufacturer and cannot be obtained readily by the user. Experimental measurements implemented in the overall PV system may be used to obtain the ANN dataset. One drawback of this method is that the generalization ability of the neural network usually degrades and some data reducing …
Discrete Particle Swarm Optimization For The Team Orienteering Problem, Ai̇şe Zülal Şevkli̇, Fati̇h Erdoğan Sevi̇lgen
Discrete Particle Swarm Optimization For The Team Orienteering Problem, Ai̇şe Zülal Şevkli̇, Fati̇h Erdoğan Sevi̇lgen
Turkish Journal of Electrical Engineering and Computer Sciences
In this paper, a novel discrete particle swarm optimization (PSO) algorithm is proposed to solve the team orienteering problem (TOP). Discrete evaluation is achieved by redefining all operators and operands used in PSO. To obtain better results, a strengthened PSO, which improves both exploration and exploitation during the search process, is employed. Our algorithm achieves the best known solutions in a short time compared to previous heuristics for the TOP.
Artificial Bee Colony Algorithm For Dynamic Deployment Of Wireless Sensor Networks, Celal Öztürk, Dervi̇ş Karaboğa, Beyza Görkemli̇
Artificial Bee Colony Algorithm For Dynamic Deployment Of Wireless Sensor Networks, Celal Öztürk, Dervi̇ş Karaboğa, Beyza Görkemli̇
Turkish Journal of Electrical Engineering and Computer Sciences
As the usage and development of wireless sensor networks increases, problems related to these networks are being discovered. Dynamic deployment is one of the main issues that directly affect the performance of wireless sensor networks. In this paper, an artificial bee colony algorithm is applied to the dynamic deployment of mobile sensor networks to gain better performance by trying to increase the coverage area of the network. The good performance of the algorithm shows that it can be utilized in the dynamic deployment of wireless sensor networks.
A Modified Particle Swarm Optimization Algorithm And Its Application To The Multiobjective Fet Modeling Problem, Ufuk Özkaya, Fi̇li̇z Güneş
A Modified Particle Swarm Optimization Algorithm And Its Application To The Multiobjective Fet Modeling Problem, Ufuk Özkaya, Fi̇li̇z Güneş
Turkish Journal of Electrical Engineering and Computer Sciences
This paper introduces a modified particle swarm algorithm to handle multiobjective optimization problems. In multiobjective PSO algorithms, the determination of Pareto optimal solutions depends directly on the strategy of assigning a best local guide to each particle. In this work, the PSO algorithm is modified to assign a best local guide to each particle by using minimum angular distance information. This algorithm is implemented to determine field-effect transistor (FET) model elements subject to the Pareto domination between the scattering parameters and operation bandwidth. Furthermore, the results are compared with those obtained by the nondominated sorting genetic algorithm-II. FET models are …
Reduction Of Torque Ripple In Dtc For Induction Motor Using Input-Output Feedback Linearization, Sebti Belkacem, Farid Naceri, Rachid Abdessemed
Reduction Of Torque Ripple In Dtc For Induction Motor Using Input-Output Feedback Linearization, Sebti Belkacem, Farid Naceri, Rachid Abdessemed
Turkish Journal of Electrical Engineering and Computer Sciences
Direct torque control (DTC) is known to produce fast responses and robust control in AC adjustable-speed drives. However, in the steady-state operation, notable torque, flux, and current pulsations occur. In this paper, nonlinear DTC of induction motor drives is presented based on a space vector pulse-width modulation scheme combined with the input-output feedback linearization technique. The variation of stator and rotor resistance due to changes in temperature or frequency deteriorates the performance of the DTC controller by introducing errors in the estimated flux linkage and the electromagnetic torque. This approach will not be suitable for high power drives such as …
Performance Comparison Of New Nonparametric Independent Component Analysis Algorithm For Different Entropic Indexes, Yusuf Sevi̇m, Ayten Atasoy
Performance Comparison Of New Nonparametric Independent Component Analysis Algorithm For Different Entropic Indexes, Yusuf Sevi̇m, Ayten Atasoy
Turkish Journal of Electrical Engineering and Computer Sciences
Most independent component analysis (ICA) algorithms use mutual information (MI) measures based on Shannon entropy as a cost function, but Shannon entropy is not the only measure in the literature. In this paper, instead of Shannon entropy, Tsallis entropy is used and a novel ICA algorithm, which uses kernel density estimation (KDE) for estimation of source distributions, is proposed. KDE is directly evaluated from the original data samples, so it solves the important problem in ICA: how to choose nonlinear functions as the probability density function (pdf) estimation of the sources.
Performance Analysis Of Wind Turbine-Driven Permanent Magnet Generator With Matrix Converter, Ramasamy Bharanikumar, A Nirmal Kumar
Performance Analysis Of Wind Turbine-Driven Permanent Magnet Generator With Matrix Converter, Ramasamy Bharanikumar, A Nirmal Kumar
Turkish Journal of Electrical Engineering and Computer Sciences
Wind energy, among all of the renewable energy sources, has made rapid developments and significant inroads in electrical power systems. With the increased use of wind energy conversion systems (WECSs), several technologies have been developed. Since WECSs are more cost competitive, the comparison of different wind generator systems is the need of the hour. Permanent magnet generators employing these technologies have some significant advantages over conventional generators, such as no need of excitation, low volume and weight, high precision, and deletion of the gearbox. A variable-speed WECS with a permanent magnet generator and a matrix converter is proposed in this …
Economic Analysis Of A Wind-Battery Hybrid System: An Application For A House In Gebze, Turkey, With Moderate Wind Energy Potential, Bahti̇yar Dursun, Ci̇han Gökçöl
Economic Analysis Of A Wind-Battery Hybrid System: An Application For A House In Gebze, Turkey, With Moderate Wind Energy Potential, Bahti̇yar Dursun, Ci̇han Gökçöl
Turkish Journal of Electrical Engineering and Computer Sciences
In this study, the energy demand of a house in Gebze, Turkey, is met by using wind energy as a primary energy source combined with rechargeable batteries. The wind-battery system is simulated by MATLAB while considering that energy continuity is maintained by using a sufficient number of batteries. A life-cycle cost analysis is carried out over a 20-year system lifetime because the operating time of the hybrid system is subject to the turbine life, usually assumed to be 20 years. The wind turbine generators considered are of various nominal powers, ranging from 0.6 to 450 kW. For each wind turbine, …
A Procedure To Specify The Weighting Matrices For An Optimal Load-Frequency Controller, Silvio José Pinto Simões Mariano, Jose Álvaro Nunes Pombo, Maria Do Rosário Alves Calado, Luis António Fialho Marcelino Ferreira
A Procedure To Specify The Weighting Matrices For An Optimal Load-Frequency Controller, Silvio José Pinto Simões Mariano, Jose Álvaro Nunes Pombo, Maria Do Rosário Alves Calado, Luis António Fialho Marcelino Ferreira
Turkish Journal of Electrical Engineering and Computer Sciences
The linear quadratic optimal regulator is one of the most powerful techniques for designing multivariable control systems. The performance of the system is specified in terms of a cost, which is the integral of a weighted quadratic function of the system state and control inputs, that is to be minimized by the optimal controller. The components of the state cost weighting matrix, Q, and the control cost weighting matrix, R, are ours to choose in mathematically specifying the way we wish the system to perform. Changing these matrices, we can modify the transient behavior of the closed-loop system. This paper …