ABSTRACT Nowadays, there are several difficulties are met in the selection of appropriate conditi... more ABSTRACT Nowadays, there are several difficulties are met in the selection of appropriate conditions, place of use, and purpose of photovoltaic (PV) systems. The reason is that electrical power output of PV system shows a non-linear variation, unlike other applications, depending on the internal resistance of electrical devices (loads) as well as radiation intensity and environmental temperature. Therefore, electrical characteristics of PV panel-load must be evaluated together for correct optimization. In this study, running an electrical device having optimized curve of linear load on a monthly basis of a panel was analyzed. At the same time, surface temperature of the panel, panel inclination angle and value of the load that concerning electrical load impact on power output of PV panels was examined experimentally and theoretically.
Bu arastirmada, Web Ortaminda Problem Temelli Ogrenmede farkli geribildirim stratejilerinin ve in... more Bu arastirmada, Web Ortaminda Problem Temelli Ogrenmede farkli geribildirim stratejilerinin ve internet kullanimina yonelik tutumun ogrencilerin akademik basarilari acisindan ogrenme uzerindeki etkileri incelenmistir. Arastirmanin calisma grubunu 9. sinifa devam eden 40 ogrenci olusturmaktadir. Ogrenciler yansiz atama yoluyla iki gruba ayrilmistir. Bu iki gruptan birincisine cevrimici dogrulayici geribildirim ve ikincisine de cevrimici yapici geribildirim stratejisi uygulanmistir. Arastirma bulgularina gore cevrimici yapici geribildirim strateji turu sunulan ogrenci grubunun, cevrimici dogrulayici geribildirim sunulan gruba gore daha basarili oldugu sonucuna varilmistir. Ayrica ogrencilerin internet kullanimina yonelik olumlu ya da olumsuz tutuma sahip olmalari genel olarak akademik basari puanlari arasinda anlamli bir fark yaratmamistir. Ote yandan dogrulayici geribildirim stratejisi uygulanan ogrenci grubunda internet kullanimina yonelik olumlu tutuma sahip ogrenciler, olumsuz tut...
2016 IEEE International Conference on Renewable Energy Research and Applications (ICRERA), 2016
Though natural droop control technique is a familiar technique to control the voltage and frequen... more Though natural droop control technique is a familiar technique to control the voltage and frequency droop in microgrid application, due to some limitations to handle different cases of application, at present time, it is not appreciable to the scientists and researchers world-wide and virtual droop control technique is developing into the most prominent control technique to regulate the frequency and voltage droop in smart grid system. In this paper, two distinct unit commitment strategies, one for islanded operation and another for grid-tied operation, are proposed for the natural gas generators backed microgrid arrangement to enhance the overall efficiency of the system and significantly scale down the fuel consumption. These novel control frameworks offer revamped implementation of renewable energy resources and minimization of the natural gas generator by using a unit commitment algorithm. Besides that, here, the virtual droop control is demonstrated for the grid tied operation of the microgrid arrangement. Furthermore, all the necessary algorithms are illustrated with proper schematics and the results are verified by Matlab simulations.
2015 International Conference on Renewable Energy Research and Applications (ICRERA), 2015
This study concentrates on multi-time series and - time scale modeling in wind speed and wind pow... more This study concentrates on multi-time series and - time scale modeling in wind speed and wind power forecasting. Different statistical models along with different time horizons are analyzed and evaluated broadly and comprehensively. For this reason, the entire study is divided into two main scientific parts. In case of making a general overview of the entire study, moving average (MA), weighted moving average (WMA), autoregressive moving average (ARMA) and autoregressive integrated moving average (ARIMA) methods are employed for multi-time series modeling. Very short-term, short-term, medium-term and long-term scales are utilized for multi-time scale modeling. Specifically, in this part of the entire study, the mentioned statistical models are presented in detail and 10-min and 1-h time series forecasting models are created for the purpose of achieving 10-min and 2-h ahead forecasting, respectively. Many useful outcomes are accomplished for very short-term and short-term wind speed and wind power forecasting.
2012 International Conference on Renewable Energy Research and Applications (ICRERA), 2012
ABSTRACT In this study, the LabVIEW modeling of a permanent magnet synchronous generator that wil... more ABSTRACT In this study, the LabVIEW modeling of a permanent magnet synchronous generator that will be used in wind turbine and the voltage control with artificial neural networks on the model are done. Typically synchronous, asynchronous and direct current generators are used in wind turbines. In the scope of this study, synchronous generators are preferred due to the advantages such as high efficiency and high reliability. the artificial neural networks are used in the control of excitation circuit in taking into account the dynamic nature of the wind.
2013 International Conference on Renewable Energy Research and Applications (ICRERA), 2013
ABSTRACT In this study a wound rotor AC induction machine which can be used in wind turbine is mo... more ABSTRACT In this study a wound rotor AC induction machine which can be used in wind turbine is modeled in LabVIEW program and the system model optimization is done with system identification (SI) method. Wind turbines are usually used as synchronous and asynchronous. In this study, to be safe and because of the advantages such as low costs, WRIM is preferred. In the control of the excitation circuit, SI method is used to provide more safe, effective and efficient control. With this method, control parameters are optimized to be used on the system. In simulations real wind data are used as input to approach reality.
4th International Conference on Power Engineering, Energy and Electrical Drives, 2013
ABSTRACT AVR (Automatic Voltage Regulator) is a part of the synchronous generator and it is respo... more ABSTRACT AVR (Automatic Voltage Regulator) is a part of the synchronous generator and it is responsible for regulating the reactive power and voltage level under normal operating terms at different load levels. The modeled system composed of the amplifier, exciter, sensor and proportional-integral-derivative (PID) controller. In order to model the system state space method is used. Also, their specifications and behaviors are discussed briefly. Simulation of the AVR system is carried out on the interface developed by Matlab GUI and the results are presented. The generator terminal voltage step responses are estimated by studying the controller parameters. In this paper, a system using Ziegler-Nichols (ZN) method as a tuning method for determining the parameters of PID control for an AVR system is proposed. Also the transient stability of AVR system with PID parameters change is proposed.
The aim of this study is to develop a framework on how to provide a guiding support to raise awar... more The aim of this study is to develop a framework on how to provide a guiding support to raise awareness about safe and conscious use of Internet. Within this scope, views of teachers working at Fatih Project and participate the in-service training about safe and conscious use of internet- has been taken. Furthermore, websites offering content about safe and conscious use of Internet examined in line with their content and views of teachers and evaluated in accordance with the predetermined criteria and the evaluation results have been analyzed. Based on the results obtained in this study, suggestions on contents which should be on an interactive website that will guide the internet users about safe and conscious use of Internet have been made
ABSTRACT Nowadays, there are several difficulties are met in the selection of appropriate conditi... more ABSTRACT Nowadays, there are several difficulties are met in the selection of appropriate conditions, place of use, and purpose of photovoltaic (PV) systems. The reason is that electrical power output of PV system shows a non-linear variation, unlike other applications, depending on the internal resistance of electrical devices (loads) as well as radiation intensity and environmental temperature. Therefore, electrical characteristics of PV panel-load must be evaluated together for correct optimization. In this study, running an electrical device having optimized curve of linear load on a monthly basis of a panel was analyzed. At the same time, surface temperature of the panel, panel inclination angle and value of the load that concerning electrical load impact on power output of PV panels was examined experimentally and theoretically.
Bu arastirmada, Web Ortaminda Problem Temelli Ogrenmede farkli geribildirim stratejilerinin ve in... more Bu arastirmada, Web Ortaminda Problem Temelli Ogrenmede farkli geribildirim stratejilerinin ve internet kullanimina yonelik tutumun ogrencilerin akademik basarilari acisindan ogrenme uzerindeki etkileri incelenmistir. Arastirmanin calisma grubunu 9. sinifa devam eden 40 ogrenci olusturmaktadir. Ogrenciler yansiz atama yoluyla iki gruba ayrilmistir. Bu iki gruptan birincisine cevrimici dogrulayici geribildirim ve ikincisine de cevrimici yapici geribildirim stratejisi uygulanmistir. Arastirma bulgularina gore cevrimici yapici geribildirim strateji turu sunulan ogrenci grubunun, cevrimici dogrulayici geribildirim sunulan gruba gore daha basarili oldugu sonucuna varilmistir. Ayrica ogrencilerin internet kullanimina yonelik olumlu ya da olumsuz tutuma sahip olmalari genel olarak akademik basari puanlari arasinda anlamli bir fark yaratmamistir. Ote yandan dogrulayici geribildirim stratejisi uygulanan ogrenci grubunda internet kullanimina yonelik olumlu tutuma sahip ogrenciler, olumsuz tut...
2016 IEEE International Conference on Renewable Energy Research and Applications (ICRERA), 2016
Though natural droop control technique is a familiar technique to control the voltage and frequen... more Though natural droop control technique is a familiar technique to control the voltage and frequency droop in microgrid application, due to some limitations to handle different cases of application, at present time, it is not appreciable to the scientists and researchers world-wide and virtual droop control technique is developing into the most prominent control technique to regulate the frequency and voltage droop in smart grid system. In this paper, two distinct unit commitment strategies, one for islanded operation and another for grid-tied operation, are proposed for the natural gas generators backed microgrid arrangement to enhance the overall efficiency of the system and significantly scale down the fuel consumption. These novel control frameworks offer revamped implementation of renewable energy resources and minimization of the natural gas generator by using a unit commitment algorithm. Besides that, here, the virtual droop control is demonstrated for the grid tied operation of the microgrid arrangement. Furthermore, all the necessary algorithms are illustrated with proper schematics and the results are verified by Matlab simulations.
2015 International Conference on Renewable Energy Research and Applications (ICRERA), 2015
This study concentrates on multi-time series and - time scale modeling in wind speed and wind pow... more This study concentrates on multi-time series and - time scale modeling in wind speed and wind power forecasting. Different statistical models along with different time horizons are analyzed and evaluated broadly and comprehensively. For this reason, the entire study is divided into two main scientific parts. In case of making a general overview of the entire study, moving average (MA), weighted moving average (WMA), autoregressive moving average (ARMA) and autoregressive integrated moving average (ARIMA) methods are employed for multi-time series modeling. Very short-term, short-term, medium-term and long-term scales are utilized for multi-time scale modeling. Specifically, in this part of the entire study, the mentioned statistical models are presented in detail and 10-min and 1-h time series forecasting models are created for the purpose of achieving 10-min and 2-h ahead forecasting, respectively. Many useful outcomes are accomplished for very short-term and short-term wind speed and wind power forecasting.
2012 International Conference on Renewable Energy Research and Applications (ICRERA), 2012
ABSTRACT In this study, the LabVIEW modeling of a permanent magnet synchronous generator that wil... more ABSTRACT In this study, the LabVIEW modeling of a permanent magnet synchronous generator that will be used in wind turbine and the voltage control with artificial neural networks on the model are done. Typically synchronous, asynchronous and direct current generators are used in wind turbines. In the scope of this study, synchronous generators are preferred due to the advantages such as high efficiency and high reliability. the artificial neural networks are used in the control of excitation circuit in taking into account the dynamic nature of the wind.
2013 International Conference on Renewable Energy Research and Applications (ICRERA), 2013
ABSTRACT In this study a wound rotor AC induction machine which can be used in wind turbine is mo... more ABSTRACT In this study a wound rotor AC induction machine which can be used in wind turbine is modeled in LabVIEW program and the system model optimization is done with system identification (SI) method. Wind turbines are usually used as synchronous and asynchronous. In this study, to be safe and because of the advantages such as low costs, WRIM is preferred. In the control of the excitation circuit, SI method is used to provide more safe, effective and efficient control. With this method, control parameters are optimized to be used on the system. In simulations real wind data are used as input to approach reality.
4th International Conference on Power Engineering, Energy and Electrical Drives, 2013
ABSTRACT AVR (Automatic Voltage Regulator) is a part of the synchronous generator and it is respo... more ABSTRACT AVR (Automatic Voltage Regulator) is a part of the synchronous generator and it is responsible for regulating the reactive power and voltage level under normal operating terms at different load levels. The modeled system composed of the amplifier, exciter, sensor and proportional-integral-derivative (PID) controller. In order to model the system state space method is used. Also, their specifications and behaviors are discussed briefly. Simulation of the AVR system is carried out on the interface developed by Matlab GUI and the results are presented. The generator terminal voltage step responses are estimated by studying the controller parameters. In this paper, a system using Ziegler-Nichols (ZN) method as a tuning method for determining the parameters of PID control for an AVR system is proposed. Also the transient stability of AVR system with PID parameters change is proposed.
The aim of this study is to develop a framework on how to provide a guiding support to raise awar... more The aim of this study is to develop a framework on how to provide a guiding support to raise awareness about safe and conscious use of Internet. Within this scope, views of teachers working at Fatih Project and participate the in-service training about safe and conscious use of internet- has been taken. Furthermore, websites offering content about safe and conscious use of Internet examined in line with their content and views of teachers and evaluated in accordance with the predetermined criteria and the evaluation results have been analyzed. Based on the results obtained in this study, suggestions on contents which should be on an interactive website that will guide the internet users about safe and conscious use of Internet have been made
— In Turkey, there are many exams for transition to a higher education institution. These exams a... more — In Turkey, there are many exams for transition to a higher education institution. These exams are all stages of life and have a great importance in the lives of students. As the severity rating of the exam, particularly students, parents and teachers are affected and exams create anxiety for students. Examination results are very important in shaping the lives of future students. Therefore, in this study is aimed to estimate the success of students, which is students' turning point in their lives, in the university entrance exam. The aim of this study, using data mining algorithms on the created student data warehouse, is to estimate the students' successes, who are taking the university entrance exam, by data mining. In this study, it has been improved a software considering Naive Bayes algorithms for student data warehouse. By that developed software by using C# languages, it is aimed to improve an early warning system that may estimate the states of the students' successes in university entrance exam for students and also for their families.
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