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The issue of modeling and incorporating uncertainty considering tractability in the planning of electrical power systems has become important for planners to maintain a reliable system. In this study, the generation and transmission expansion planning is performed considering the uncertainty in load and wind generation. The sample average approximation (SAA) method is used to obtain deterministic equivalent of stochastic optimization problems in a mixed integer linear programming (MILP) framework. The problem is formulated with a large number of independent samples, each small in size, to reduce computational effort. The results are presented by comparing them with investment decisions made using a single large sample size. It is observed that the presented approach can be used as an alternative in terms of sufficiently operationalizable to produce optimal investment decisions in mathematical programming.

In this study, the optimization of the penetration level and allocation of distributed generation (DG) in single- and multiple- DG concepts are investigated on three typical test networks in order to obtain more reliable DG-integrated power system and develop some rules to be used at network management centers. An improper integration of DG units, without detailed analysis, decreases the reliability and efficiency of power networks. Although DGs can decrease power loss and improve voltage profile, they can cause the congestion on transmission lines at some penetration levels. For this reason, line flows are also considered besides power loss and voltage profile in this paper. In this manner, a threshold penetration level is investigated by considering both single- and multiple- DG concepts. According to the results of optimization, voltage profiles and line flows are observed on the IEEE test networks while minimizing power loss in order to reveal some rules in terms of power system planning, Bu çalışmada, dağıtılmış enerji üretim tesisleri (DEÜ) entegre edilmiş elektrik şebekelerinin daha güvenilir çalıştırılabilmesine ve yönetilebilmesine yardımcı olması noktasında bazı kurallar geliştirilebilmesi amacıyla üç farklı şebeke üzerinde farklı sayıdaki DEÜ tesislerinin optimum katılım oranlarının (KO) ve bağlanma noktalarının belirlenmesine yönelik analizler yapılmıştır. DEÜ entegre edilmiş şebekelerin detaylı bir analizi yapılmaksızın şebekeye rastgele dahil edilmesi şebekenin güvenilirliğinin ve veriminin azalmasına neden olabilmektedir. DEÜ konsepti her ne kadar şebeke kayıplarında azalma ve gerilim profillerinde iyileştirmeye yardımcı olsa da, mevcut iletim hatlarının kapasiteleri bazı KO seviyelerinde yetersiz kalabilmektedir. Bu nedenle, bu çalışmada şebeke kayıpları ve gerilimlerin yanı sıra mevcut hat kapasiteleri de analizlerde dikkate alınmıştır. Bu bağlamda, tek ve birden fazla DEÜ bağlantılarında bir eşik KO değerinin olup olmadığı araştırılmıştır. Optimizasyon sonuçları neticesinde, şebeke planlaması açısından bazı temel kuralların elde edilmesi amacıyla şebeke kayıpları minimize edilirken gerilim profili ve hat akışları IEEE test şebekeleri üzerinde gözlemlenmiştir

High penetration of photovoltaic (PV) systems is expected to play important roles as power generation source in the near future. One of the typical deployments of PV systems is without supervisory mechanisms to monitor the physical conditions of cells or modules. In the longer term operation, the cells or modules may undergo fault conditions since they are exposure to the environment. Manually module checking is not recommended in this case because of time-consuming, less accuracy and potentially danger to the operator. Therefore, provision of early automatic diagnosis technique with quick and efficient responses is highly necessary. Since high accuracy is the important issue in the diagnosis problems, the paper present fault diagnosis method using three-layered artificial neural network. A single artificial neural network (ANN) is not suitable to provide precise solution for this fault identification. Therefore, several ANNs are developed, then automatic control based module voltage terminal is established. The proposed method is simple and accurate to detect the exact location of short-circuit condition of PV modules in array.

In the last couple of years Bluetooth has gained a large share in the market of home and personal appliances. It is now a well established technology a short range supplement to the wireless world of 802.11. The two main trends of research that have sprung from these developments are directed towards the coexistence and performance issues of Bluetooth and 802.11 as well as the co-existence in the very short range of multiple Bluetooth devices. Our work aims at thoroughly investigating different aspects of co-channel interference and effects of transmission power, distance and 802.11 interference on Bluetooth connections., {"references":["Bluetooth Specivication SIG,(Online), Available: http://www.bluetooth.com","N. Abramson, The throughput of packet broadcasting channels, IEEE Trans.Comm., vol. COM-25, pp.117-128, Jan.1997","J. Haarsten, Bluetooth - the universal radio interface for ad hoc, wireless connectivity, Erricsson Review, no.3, pp.110-117, 1998.","S.Zurbes, Considerations on Link and System Throughput of Bluetooth Networks, PIMRC 2000, pp.1315-1319","C.M.Cordeiro, D.P.Agrawal, D.H.Sadok, Interference Modelling and Performance of Bluetooth MAC protocol, IEEE Trans. Comm. Vol 2, No.6, Nov. 2003. pp.1240-1246","J.P.Lynch, Co-channel Interference in Bluetooth Piconets, Virginia Polytechnic Institute, Master of Science Thesis, Ch.3, 2002","C.Hsu, Y.J.Joung, An NS Based Bluetooth Topology Construction Simulation Environment, Proceedings of the 36th annual Simulation Symposium, ANSS 2003","G.Tan, Blueware: Bluetooth Simulator for NS-2, (Online), Available from: godfreyt@lcs.mit.edu","Bluetooth Extension for NS, (Online}, Available:\nhttp://oss.software.ibm.com.d/developmentworks/opensource/bluehoc/\n[10] Matlab Simulink, (Online), Available: http://www.mathworks.com/matlabcentral/bluetooth_file\n[11] Network Simulator (NS-2), (Online), Available: http://www.mash.cs.berkley.edu/ns"]}

ÖZET FOTOVOLTAİK JENERATÖRLERİN KISMİ GÖLGELENME VE UYUMSUZLUK KOŞULLARINDA BULANIK MANTIK KONTROLÖR İLE MAKSİMUM GÜÇ NOKTASI KONTROLÜ VE FARKLI SİSTEM KONFİGÜRASYONLARMIN KARŞILAŞTIRILMASI KARATEPE, Engin Doktora Tezi, Güneş Enerjisi Enstitüsü Tez Yöneticisi: Prof. Dr. Metin ÇOLAK ve Dr. Mutlu BOZTEPE Bu tez çalışmasının ilk aşamasında farklı sıcaklık ve ışınım koşullan için güneş pili tek diyot eşdeğer devre parametrelerinin değişimi incelenmiş ve yapay sinir ağlan tabanlı yeni bir model geliştirilmiştir. Tezin ikinci aşamasında, geliştirilen güneş pili modeli kullanılarak, seri- paralel, tam-çapraz, ve köprü bağlantı konfigürasyonlannda fotovoltaik (PV) örgülerin kısmi gölgelenme ve elektriksel uyumsuzluk koşullarına verdiği cevap, sistem verimi ve maksimum güç noktası takibi geriliminin değişim aralığı açısından ayrıntılı olarak analiz edilmiştir ve birbirleriyle karşılaştinlmıştir. Tezin üçüncü aşamasında, kısmi gölgelenmeden dolayı oluşan güç kayıplarım azaltmak için yeni bir kontrol sistemi önerilmiştir. PV örgüdeki her bir kola, giriş gücünü PV örgünün çıkışından alan bir DC/DC dönüştürücü bağlanarak oluşturulan bu sistem, belirli bir seviyede gölgelenmiş modülleri devre dışı bırakarak, PV sistemi yerel maksimum güç noktalarına takılmadan çalıştırabilmektedir. DC/DC dönüştürücünün kontrolünde bulanık mantık kullanılmıştır. AmaMar sSzciHer: Fotovoltaik, kısmi gölgelenme, maksimum güç noktası, bulanık mantık, elektriksel uyumsuzluk, sistem sentezi. vu ABSTRACT MAXIMUM POWER POINT TRACKING CONTROL for PARTIALLY SHADED PHOTOVOLTAIC ARRAY amd MISMATCHING CONDITIONS USING FUZZY CONTROLLER amd COMPARISON of DIFFERENT INTERCONNECTED PHOTOVOLTAIC ARRAYS KARATEPE, Engin PhD in Solar Energy Institute Supervisors: Prof. Dr. Metin ÇOLAK and Dr. Mutlu BOZTEPE In the first stage of this thesis, a neural network based approach solar cell model is developed for improving the accuracy of the electrical equivalent circuit of solar cell for the all operating conditions. The accuracy and generalization of the proposed model is demonstrated by comparing test results with actual data. In the second stage, the effects of inhomogeneous irradiation distribution on the energy output of different interconnected configurations of photovoltaic arrays, such as series- parallel, total cross tied and bridge-link, are analyzed and compared. In the third stage, a novel power compensation control system for partially shaded photovoltaic systems. The proposed system can track the global maximum power point of partially shaded PV arrays by forward bias of bypass diodes of the shaded modules by using a DC/DC converter. A fuzzy control algorithm is used for regulating DC/DC converter. The effectiveness of the proposed system investigated and is confirmed from some partially shaded scenarios. Keywords: Photovoltaic, partially shaded, maximum power point, fuzzy logic, mismatching, system synthesis. 175