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Recently, while electric vehicles (EV) have substituted the fossil fuel vehicles, the design of the electrical motors with more efficient and less mechanical converters has become mandatory due to the weighting gears, mechanical differentials, and other cost-increasing parts. To overcome these problems, double electrical motors with low speed and high torque have been designed and used in the rear wheels of the EVs without any gearbox and mechanical differential. In this study, a novel outer rotor line-start hybrid synchronous motor is proposed as another solution. For this aim, four different hybrid rotor types, including magnets and rotor bars, have been designed and analyzed. Calculation and estimation of all parameters to design a motor are introduced. All of the analyses were carried out by Finite Elements Method (FEM). One of the analyzed motors, which is called Type-D was selected and implemented because of the best startup performance and better steady-state behavior under the rated load and overload. While holding this motor at synchronous speed under nominal load, in case of overloading, it remained in asynchronous mode, thus maintaining the sustainability of the system. Obtained results prove that the newly proposed outer rotor LSSM has the advantages of both synchronous motor and asynchronous motor. All of the experimental results validate the simulations well. The effects of the magnet alignments and dimensions on the performance of the motors are presented. C1 [Tumbek, Mustafa; Kesler, Selami] Pamukkale Univ, Dept Elect & Elect Engn, TR-20160 Denizli, Turkey.

Energy management strategies for an electric vehicle (EV) with multiple power sources have been widely described in literature. The investigated energy sources are batteries, ultracapacitors, fuel cells, flywheels and solar panels. The management strategy decides how to combine two or more sources in an optimal way. However, the behavior of these sources and also the behavior of the electric drives depend on their temperature. Moreover, the temperature can have extreme values in automotive applications and affect the energy management task. In this paper, to investigate the temperature effect on battery/ultracapacitor powered EV, temperature dependent models are presented for these storage components, as well as for the drive train components itself: power electronics and motor. The average motor iron loss and ultracapacitor loss tend to decrease with increasing temperature, while the average motor copper loss and power electronics loss tend to increase with increasing temperature. These two opposing trends cause the total loss of the drive train to have a rather small variation with temperature for the considered EV and in the considered temperature range. By consequence, the energy management strategy of the EV does not have to depend on the temperature in order to obtain maximal efficiency. (C) 2017 Elsevier Ltd. All rights reserved.

The ubiquity of Au-bearing arsenian pyrite in hydrothermal ore deposits suggests that the coupled geochemical behaviour of Au and As in this sulfide occurs under a wide range of physico-chemical conditions. Despite significant advances in the last 20years, fundamental factors controlling Au and As ratios in pyrite from ore deposits remain poorly known. Here we explore these constraints using new and previously published EMPA, LA-ICP-MS, SIMS, and μ-PIXE analyses of As and Au in pyrite from Carlin-type Au, epithermal Au, porphyry Cu, Cu-Au, and orogenic Au deposits, volcanogenic massive sulfide (VHMS), Witwatersrand Au, iron oxide copper gold (IOCG), and coal deposits. Pyrite included in the data compilation formed under temperatures from ~30 to ~600°C and in a wide variety of geological environments. The pyrite Au-As data form a wedge-shaped zone in compositional space, and the fact that most data points plot below the solid solubility limit defined by Reich et al. (2005) indicate that Au1+ is the dominant form of Au in arsenian pyrite and that Au-bearing ore fluids that deposit this sulfide are mostly undersaturated with respect to native Au. The analytical data also show that the solid solubility limit of Au in arsenian pyrite defined by an Au/As ratio of 0.02 is independent of the geochemical environment of pyrite formation and rather depends on the crystal-chemical properties of pyrite and post-depositional alteration. Compilation of Au-As concentrations and formation temperatures for pyrite indicates that Au and As solubility in pyrite is retrograde; Au and As contents decrease as a function of increasing temperature from ~200 to ~500°C. Based on these results, two major Au-As trends for Au-bearing arsenian pyrite from ore deposits are defined. One trend is formed by pyrites from Carlin-type and orogenic Au deposits where compositions are largely controlled by fluid-rock interactions and/or can be highly perturbed by changes in temperature and alteration by hydrothermal fluids. The second trend consists of pyrites from porphyry Cu and epithermal Au deposits, which are characterised by compositions that preserve the Au/As signature of mineralizing magmatic-hydrothermal fluids, confirming the role of this sulfide in controlling metal ratios in ore systems.

Energy usage and environment pollution in the transportation are major problems of today's world. Although electric vehicles are promising solutions to these problems, their energy management methods are complicated and need to be improved for the extensive usage. In this work, the heuristic optimization methods; Differential Evolution Algorithm, Genetic Algorithm and Particle Swarm Optimization, are used to provide an optimal energy management system for a battery/ultracapacitor powered electric vehicle without prior knowledge of the drive cycle. The proposed scheme has been simulated in Matlab and applied on the ECE driving cycle. The differences between optimization methods are compared with reproducible and measurable error criteria. Results and the comparisons show the effectiveness and the practicality of the applied methods for the energy management problem of the multi-source electric vehicles.

This paper presents an integrated design of a drivetrain for a single-person ultra-light electric vehicle (ULEV). To calculate losses and efficiency of the inverter, the permanent magnet synchronous machines (PMSMs) and the gearbox, parameterised analytical models are used. For the gearbox - which has a single gear ratio - the studied parameters are the gear ratio, the number of stages, the number of teeth and the module of each spur gear combination. The novelty of the paper is that it learns how the total average efficiency and the total mass of the drivetrain depend on the gear ratio, on the number of stages in the gearbox, on the motor parameters and on the chosen several driving cycles including the new European driving cycle (NEDC). On the basis of the presented results, it is possible to choose the right configuration of power electronics, PMSM and gearbox in order to have a good trade-off between high efficiency and low mass.

In recent years, some converter structures and analyzing methods for the voltage regulation of stand-alone self-excited induction generators (SEIGs) have been introduced. However, all of them are concerned with the three-phase voltage control of three-phase SEIGs or the single-phase voltage control of single-phase SEIGs for the operation of these machines under balanced load conditions. In this paper, each phase voltage is controlled separately through separated converters, which consist of a full-bridge diode rectifier and one-IGBT. For this purpose, the principle of the electronic load controllers supported by fuzzy logic is employed in the two-different proposed converter structures. While changing single phase consumer loads that are independent from each other, the output voltages of the generator are controlled independently by three-number of separated electronic load controllers (SELCs) in two different mode operations. The aim is to obtain a rated power from the SEIG via the switching of the dump loads to be the complement of consumer load variations. The transient and steady state behaviors of the whole system are investigated by simulation studies from the point of getting the design parameters, and experiments are carried out for validation of the results. The results illustrate that the proposed SELC system is capable of coping with independent consumer load variations to keep output voltage at a desired value for each phase. It is also available for unbalanced consumer load conditions. In addition, it is concluded that the proposed converter without a filter capacitor has less harmonics on the currents.

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This study presents a model of a drivetrain for an integrated design of a light electric vehicle (EV). For the drivetrain of each front wheel of the single-person, battery-powered EV tricycle consists of a battery, an inverter, and an outer rotor permanent magnet synchronous motor (PMSM), which is connected to an in-wheel gearbox. The efficiency of the inverter, motor, and gearbox is analyzed over the New European Driving Cycle. To calculate the losses and efficiency of the PMSM, the power electronics in the inverter and gearbox are used. The analytical models provide a fat, but less accurate result, useful for optimization purposes. To accurately predict the efficiency of the PMSM, a finite element model is used. The models are validated by test setups. Correspondingly, a good agreement between the measurements and the calculated results is achieved. A parameter study is performed to investigate the influence of the detailed component parameters (i.e., outer rotor radius, gear ratio, and number of pole pairs and stator slots) on the average efficiency of the drivetrain.

The next century will witness a breakthrough in terms of renewable energy sources, particularly solar energy and its derivatives. This renewable and enormous energy source offers a solution to the energy problem all over the world. One of the areas in which solar energy is used is the photovoltaic (PV) systems. The main element of this sector, however, is the pure silicon technology. Because, most efficient PV cells are made of silicon and its degree of purity is very important. The most commonly used types of these materials for PV energy conversion are thin Film, mono-crystalline and poly-crystalline silicon, which are also known as silicon modules or panels. However, performances of these modules vary by region. This study focuses on analyzing different three-type PV panels and determining the optimal panel type for Kahramanmaras with three separate PV systems, each 3-kWp and grid-connected. Besides, this study is the first research project to consider all aspects to determine optimal PV power system in the region. To this aim, three different PV systems consisting of thin film, mono-crystalline and poly-crystalline silicon panels were installed. The amount of energy generated by each system, cost analysis, annual incomes, breakeven points, installation area occupied by the system and total weights of each system are evaluated for each panel type used in the installed system and potential energy to be generated by solar energy in the region was considered. Following energy generation which lasted one year and at the end of the 30-year operation period, it is concluded that poly-crystalline silicon panels are the most optimal panel for the region because it yields the highest annual incomes and the shortest breakeven point for the investors. (C) 2015 Published by Elsevier Ltd.

Shading analyzer systems are necessary for selecting the most suitable installation site to sustain enough solar power. Afterwards, changes in solar data throughout the year must be evaluated along with the identification of obstructions surrounding the installation site in order to analyze shading effects on productivity of the solar power system. In this study, the shading analysis tools are introduced briefly, and a new and different device is developed and explained to analyze shading effect of the environmental obstruction on the site on which the solar power system will be established. Thus, exposure duration of the PV panels to the sunlight can be measured effectively. The device is explained with an application on the installation area selected as a pilot site, Denizli, in Turkey.

This study presents an analysis of solar energy potential and data with seasonal variation in region of Manavgat in Antalya, which has one of the highest solar energy potential in Europe. Expectation in the region is simulated for every month and measurements taken from PV power system installed there are compared with simulated results in winter season. Also, some actual harvested data from thin films and monociystalline types are presented as a case study to evaluate the solar energy potential of the region, comparatively. Besides, importance of the sun tracking system is emphasized by simulation studies via PV Geographical Information System (PVGIS) from point of increasing the yields in selected region. Estimated results from two-axis tracking system are evaluated and compared with output of the fixed-angle PV systems installed there for both thin film and monocrystalline type PV panels. Also, temperature effects on performance of the PV systems are reviewed briefly because of daily high temperature of the region. In particular, it is observed that harvested solar energy from thin film type panels is close to the monocrystalline types, depending on the less effects of high ambient temperature on thin film PV panel's efficiency with respect to the monociystalline type. Specifically, despite the high solar energy potential, this PV power system installation is the first project in the region. Thanks to this project it is evaluated that thin-film PV panels can be used in the region more favorable, which can be obtained cheaper than the others. Crown Copyright (C) 2014 Published by Elsevier Ltd. All rights reserved.

Dimming can be accomplished commonly by switching frequency and pulse density modulation techniques and a variable inductor. In this study, a variable power density modulation (VPDM) control technique is proposed for dimming applications. A fluorescent lamp is operated in several states to meet the desired lamp power in a modulation period. The proposed technique has the same advantages of magnetic dimming topologies have. In addition, a unique and flexible control technique can be achieved. A prototype dimmable electronic ballast is built and experiments related to it have been conducted. As a result, a 36WT8 fluorescent lamp can be driven for a desired lamp power from several alternatives without modulating the switching frequency.

Background: Ischemic stroke is the leading cause of mortality worldwide and a major contributor to neurological disability and dementia. Terutroban is a specific TP receptor antagonist with antithrombotic, antivasoconstrictive, and antiatherosclerotic properties, which may be of interest for the secondary prevention of ischemic stroke. This article describes the rationale and design of the Prevention of cerebrovascular and cardiovascular Events of ischemic origin with teRutroban in patients with a history oF ischemic strOke or tRansient ischeMic Attack (PERFORM) Study, which aims to demonstrate the superiority of the efficacy of terutroban versus aspirin in secondary prevention of cerebrovascular and cardiovascular events. Methods and Results: The PERFORM Study is a multicenter, randomized, double-blind, parallel-group study being carried out in 802 centers in 46 countries. The study population includes patients aged ≥55 years, having suffered an ischemic stroke (≤3 months) or a transient ischemic attack (≤8 days). Participants are randomly allocated to terutroban (30 mg/day) or aspirin (100 mg/day). The primary efficacy endpoint is a composite of ischemic stroke (fatal or nonfatal), myocardial infarction (fatal or nonfatal), or other vascular death (excluding hemorrhagic death of any origin). Safety is being evaluated by assessing hemorrhagic events. Follow-up is expected to last for 2–4 years. Assuming a relative risk reduction of 13%, the expected number of primary events is 2,340. To obtain statistical power of 90%, this requires inclusion of at least 18,000 patients in this event-driven trial. The first patient was randomized in February 2006. Conclusions: The PERFORM Study will explore the benefits and safety of terutroban in secondary cardiovascular prevention after a cerebral ischemic event.

Nowadays, obtaining and gaining the control of energy sources are difficult and costly. Besides, most of the wars are due to energy aspects. Therefore, energy saving has now become very important for all countries in the world. Furthermore, the energy management and saving matters are adopted as fundamental policies by the governments as well. Some projects based on energy efficiency are even supported by the nonprofit foundations. Additionally, countries are exploring new energy sources and finding new techniques in using energy thrifty. The streetlights or outdoor lighting items are used up a plenty of energy in vain in some part of the day such as twilight duration because of using conventional photocell relays. Changing in the sunrise and the sunset times during the year, profiling duration from the daylight is different for each day. As the photocell relays have different inner impedance versus daylight, and the weather may be cloudy or clear, they can be turned-on early and can be turned-off lately. Besides, these relays are not so sensitive to twilight. Therefore, the amount of energy wasted during the year is going to be considerable. The duration of the consumption in vain is one hour per day at least. However, in case of using astronomical time relays, since the sunrise and the sunset times related to different time zone can be calculated during the year, all of the streetlights can be controlled by different offset time and can be saved respectable amount of energy per year. In this study, the importance of using the astronomical relays for outdoor lighting for energy saving and efficiency is discussed. The operating principal of these relays is analyzed by purposed method and compared with that of NOAA. An implementation of an astronomical time relay for Denizli City in Turkey is selected as a case study. It was proved that the energy consumption in vain one hour per day during the year is remarkable amount in the selected plot application area. Copyright (C) 2009 Praise Worthy Prize S.r.l. - All rights reserved.

The speed control at large range for wound-rotor induction machines can be implemented by using different vector based methods from either or both the stator and the rotor Side. One of these is to apply voltage with slip frequency on rotor windings through the rings. But, throughout the application, dangerous effects on the machine dynamics occur when effective value of the voltage applied on rotor windings is not adjusted by any intelligent control system especially at the application moment. In this study, firstly, the effects on the instantaneous rotor current and induced torque waveforms throughout the voltage injecting in the rotor windings are examined by simulations and experiments. Afterwards, the determined transient and harmful effects on the mentioned dynamics are tried to reduce by the fuzzy logic based control system using DSP. For the experimental studies, an IGBT inverter fed by DC link converter in rotor side is designed and employed Thus, power converter rating is reduced hi the control system, TMS320F2812 DSP is used together with fuzzy logic based space vector pulse width modulated inverter in order to control of amplitude and frequency of the injected voltage with same phase in accordance with the voltage induced in rotor circuit. The power flow between rotor windings and system in which stator side is directly connected to the grid is analyzed at different operation mode. A large range speed controller system with power recovery drive is implemented not only braking in regenerative region but holding the speed at the reference under unexpected load condition changing suddenly as well. For simulation studies, a C/C++ algorithm is developed in order to predict the performance of proposed model and results supported by experimental studies are presented and discussed Copyright (C) 2008 Praise Worthy Prize - All rights reserved.