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With the increased importance of energy all over the world, new energy sources are needed to meet the energy demand. However, the solution to energy demand is not only finding new energy resources but also using currently consumed energy efficiently. Accordingly, decreasing the energy consumption in urban electric railway transport has become an important issue. Investment in urban railway transport is increasing continually because it is more economical, safe, and sustainable than other modes in local transportation. For new investments related to urban railway transport, decision-makers generally make an assessment that will include economic, demographic, and environmental impacts. In this study, a comprehensive top-down decision-making system for urban railway route selection was engineered by taking into account socio-economic criteria as well as technical criteria. In the context of surveys conducted with experts in the choice of railway system routing, five socio-economic criteria (passenger potential, construction cost, integration-access, zoning-ownership, travel time) and five technical criteria (vehicle energy consumption, regenerative energy, traffic operations, power supply system, efficient driving techniques) were determined. In the analysis, the analytical hierarchy process (AHP) method, one of the multi-criteria decision-making methods, was used to determine the best route among alternative routes based on all criteria.

It is important to accurately estimate instantaneous voltage flicker magnitudes and frequencies in order to correctly evaluate voltage fluctuations. Voltage flicker is a problem in electric power quality. Different approaches used to determine the magnitude of the voltage flicker have been presented: measurement methods generally use a flickermeter device. Simulation methods require a computer model of the disturbing load and the flickermeter. Calculation methods necessitate a simplified empirical formula. Estimation algorithms are based on the estimation of the voltage flicker components. In this paper, two models of voltage flicker are discussed: L p estimation algorithms utilizing L 1 , L 2 and L ∞ norms are used to estimate the voltage magnitudes of the flicker signals as well as the fundamental voltage magnitude. The main result is that it is possible to design an L p estimator to identify flicker frequency and amplitude from time series measurements.

In this paper, to what extent a cogeneration system’s fixed and variable costs and profits are affected from the exchange rate model implemented in the country is examined. An autoproductor system, as known, uses a part of its electrical energy production for its own requirements while selling the remaining energy to the regional energy corporation. As a function of the load factor and the fuel cost, the production cost and energy sale income of the system are influenced much by the exchange rate model of the country. A cost analysis of a natural gas cogeneration (autoproductor) system has been performed for the numerical application, based on the monetary program supported by the IMF commenced in January 2000. In order to investigate the effect of the change in exchange rate model (introducing the floating exchange rate model) on the fuel cost, both the characteristics of the IMF program and some various forecasting methods have been utilized.

String insulators are generally used to insulate and carry the line conductor in the overhead power transmission lines. The number of insulator units depends on the operation voltage and other factors such as contamination, mechanical strength, lightning, and altitude. When AC voltage is applied to the string, the voltage distribution is non-uniform across a string insulator. To evaluate these voltages, string efficiency term is used. In conventional calculations of the voltage distribution over a string insulator and string efficiency, it is assumed that the insulator surface is clean, dry, and also there is no wind. In this study, the voltage distribution over an insulator string of suspension insulators and the string efficiency have been investigated with respect to the atmospheric conditions such as wind velocity, wind direction and contamination of insulator surface. All analysis and calculations have been carried out for an overhead power line between Karaman-Karasinir in Turkey having 66-...

The losses in the power systems should be low as possible as. Saving energy instead of loses (kWh) in power utilities can supply much more energy to the consumers. The lower losses the more energy is saved and thus the power system becomes more economical. In recent years, the increasing number of applications and power ratings of the devices which have nonlinear voltage-current characteristics cause voltage waveform distortion and additional losses. While evaluating losses considering harmonics will provide more contribution to obtain more accurate results. In this study, Artificial Neural Networks (ANN) method has been presented to predict the harmonic losses in unbalanced power systems by using the data from balanced power system with nonlinear loads., Elektrik güç sistemlerinde meydana gelen kayıpların mümkün olduğunca küçük tutulmasına çalışılmalıdır. Tasarruf edilen her kayıp kWh'in yerine mevcut üretim tesislerinden tüketicilere faydalı enerji verilebilir. Şebeke kayıplarındaki her azalma, üretim maliyetinin azalması ve böylece enerji sisteminin ekonomikliğinin artması anlamındadır. Son yıllarda lineer olmayan gerilim-akım karakteristiğine sahip cihazların sayı, uygulama ve güç değerlerinin artması, gerilim dalga şeklinin bozulmasına ve ek kayıpların oluşmasına neden olmaktadır. Kayıplar hesaplanırken harmoniklerin de dikkate alınması daha doğru sonuçlara ulaşmamıza katkı sağlayacaktır. Bu çalışmada; dengeli ve lineer olmayan yükler içeren elektrik sistemi verilerinden faydalanarak, dengesiz güç sistemlerinde harmonik kayıplarının tahmin edilmesi için Yapay Sinir Ağları (YSA) yaklaşımı sunulmuştur.

Harmonic distortion and flicker severity have become the main concerns in power transmission networks. Different types of harmonic and flicker sources exist in power systems, such as arc furnaces and cycloconverters. A power quality problem found in networks can cause additional temperature rise, losses, noise, and irritation in the lighting equipment. The aim of this study is to identify the level of harmonics and flicker in the 380-kV transmission network of Turkey. The measurement and analysis are performed using a specially developed power quality analyzer. The effects of harmonics and flicker on the network are discussed based on real measurement results. Moreover, the measurement results are compared to the current regulations in Turkey.

This paper presents measurement system and detailed analysis of power quality at the substation of two different wind farm sites which are of low and high power rate. Measurement system has been designed using a data acquisition board (DAQ), Labview software, Matlab programming and a portable PC. The system has been installed at medium voltage level at substation of both wind farms. The real measurement results at substations are compared to current regulations in Turkey. (C) 2009 Elsevier Ltd. All rights reserved.

oz YÜKSEK LİSANS TEZİ DEMIRCILER-SOGUTLU- SALMANIPAK (NARLI-KAHRAMANMARAŞ İLİ) JEOLOJİSİ VE PETROGRAFİSİ Tuğba ASLAN İNAN ÇUKUROVA ÜNİVERSİTESİ FEN BİLİMLERİ ENSTİTÜSÜ JEOLOJİ MÜHENDİSLİĞİ ANABİLİM DALI Danışman: Prof. Dr. Fikret İŞLER Yıl:2004, Sayfa: 48 Jüri: Prof. Dr. Fikret İŞLER :Doç. Dr. Osman PARLAK :Yrd. Doç. Dr. Ergül YAŞAR Yüksek lisans tezi olarak hazırlanan bu çalışmada; Kahramanmaraş ilinin 30 km güneydoğusunda Söğütlü-Demirciler-Salmampak Köyleri arasında kalan sahada jeolojik petrografik çalışmalar yapılmıştır. Çalışma alanının 1/25.000 ölçekli jeoloji haritası hazırlanmış ve sahada yüzeylenen kayaçlar mineralojik ve petrografik açıdan detaylı bir şekilde incelenmiştir. Sahada en yaşlı birimi Kretase yaşlı Ofiyolit Napı oluşturmaktadır. Bunların üzerine sırasıyla dolomitik kireçtaşı, killi kireçtaşı, yer yer aralarında çört yumruları, bazalt ve çakıltaşı, kumtaşı, kiltaşı, çamurtaşı ardalanması bulunmaktadır. En üstte ve sahanın büyük bir bölümünü kaplayan alüvyon bulunmaktadır. Anahtar Kelimeler: Ofiyolit, Dolomitik kireçtaşı, Bazalt, Alüvyon. ABSTRACT MSc THESIS GEOLOGY AND PETROGRAFY OF DEMİRCİLER-SÖ?ÜTLÜ- SALMANIPAK (NARLI-KAHRAMANMARAŞ) Tuğba ASLAN İNAN DEPARTMENT OF GEOLOGY ENGINEERING INSTITUTE OF NATURAL AND APPLIED SCIENCES UNIVERSITY OF ÇUKUROVA Supervisor: Prof. Dr. Fikret ÎŞLER Year: 2004, Pages: 48 Jury : Prof. Dr. Fikret İŞLER : Assoc. Prof. Dr. Osman PARLAK : Asist. Prof. Dr. Ergül YAŞAR In this master thesis, geological and petrographical properties of the study area which located between Demirciler-Söğütlü- Salmanipak villages, 30 km Southeast Kahramanmaraş. A 1/25000 scaled geological map may prepared and rocks outcropped in the study area were investigated for their petrographical and minerological properties. The oldest rock unit is Cretacecus Ofiolite Napes in the study area. These rocks were overlien by dolomitic limestone, marly limestone, bazalts, chert pebbles, conglomerate, sandstone, mudstone, claystone alternation. All of these rocks were overlien by allavium that covers most of the study area. Key words: Ofiolite, Dolomitic limestone, bazalts, allavium II 56

Due to increasing energy requests, ultra-high-voltage power systems are coming more to the fore. In this paper, power systems of 1000 kV are especially taken into account. New simulation technologies are required to be able to understand the behavior of 1000 kV power systems and to guide the development of 1000 kV equipment. The paper explains two related subjects: a simulation method for evaluating the unbalanced voltage and current conditions that occur in nontransposed transmission lines; and a modeling method that can analyze the surge behavior of low attenuation 1000 kV lines.

One of the effects of voltage and current harmonics within the power systems is ageing of the insulation of electrical equipment and components and thus shortening of their useful life. In the rotating machines harmonics cause additional stator and rotor losses and reduce the output torque. In this sense, the purpose of this paper is to determine an electric motor life (together with motor efficiency) according to the temperature increase due to harmonic currents.