bluuebunny/crossref_metadata_2025 huggingface dataset:
A Novel Power Quality Monitor Placement Method Using Adaptive QuantumInspired Binary Particle Swarm Optimization
Authors: A. A. Ibrahim  , A. Mohamed  , H. Shareef
Published: May 2017

This paper presents a novel method for solving optimal power quality monitor placement problem in monitoring voltage sags in power systems using the adaptive quantum-inspired particle swarm optimization (PSO). The optimization considers multi objective functions and handles observability constraint determined by the concept of the topological monitor reach area. The overall objective function consists of two functions which are based on monitor overlapping index and sag severity index. In this algorithm, the standard quantum-inspired binary PSO is modified by applying the concept of artificial immune system as an adaptive element to make it more flexible towards better quality of solution and computational speed. The proposed algorithm is applied on the IEEE 30-bus transmission system and the IEEE 34-node distribution system and compared to the conventional PSO.
Dimension and Production of a turbine Type Francis
Authors: Elmo Thiago Lins Cöuras Ford  , Ana Catarina Mendes Barradas  , José Ubiragi de Lima Mendes  , José Ubiragi de Lima Mendes  , Rubens  Maribondo do Nascimento
Published: May 2017

Now in Brazil, most of the produced electric power and originating from hydroelectric that for your time are used of hydraulic turbines to transform the hydraulic energy (the pressure energy and the kinetic energy) of a flow of water, in mechanical energy and for your time in electric power. However they can also be used for generation of energy in small scale, for the isolated communities. In that way, this work looked for dimension and to manufacture a turbine of the type Francis in kindred scale of being used in small communities.
Adjustment in the Least Square Meaning of a Neural Model for Electric Arc Quenching in High Voltage Circuit Breakers
Authors: A. Ziani  , H. Moulai
Published: May 2017

In this paper, a simulation of the breaking arc in high voltage circuit breakers based on a combination of the least square and the neural networks techniques will be presented. A simulation program has been developed by the means of Matlab software that enables to adapt polynomial functions to the neural simulations. The obtained results show the efficiency of the method on a 245kV/50kA line breaker.
Paper Certificate SMART GRID framework for Pakistan” Perception to practicality
Authors: Arjumand Samad
Published: May 2017

As moving further into the digital age of the 21st century, Pakistan. and rest of the world is becoming increasingly dependent upon electric power. Despite the colossal potential of its energy resources, still Pakistan remains energy deficient. As a consequence, the crucial energy supplies today are not adequate to meet even the present demand. Similarly Line losses are a major issue in Pakistan. We are losing 35 to 40 billion per annum due to inefficiency in power distribution [4], While continuing blackouts or load shedding as it is commonly known, has always been a staple of daily life in Pakistan (figure 1). the dilemma has turned out to be acute since the preceding couple of months. The only way to tackle such colossal plight collectively is to implement smart grid infrastructure into our system. Also integrated use of smart grid would enhance the cooperation between the different sectors of the energy mix to provide an optimal solution in the electrical energy scenario of Pakistan. Smart grid is nothing but a concept/idea needed to run our present day Electrical power system in a more effective, more systematic and less error prone way. To achieve this way of wisdom, we must keep the end or the output required in our mind. Accommodating the present infrastructure with newer and more reliable modern day technologies are also a target of the Smart grid planning. Similarly Clean, green energy structure is an inherent requirement of smart grid development [6].It would provide a long term economic and social benefit to the existing structure of the society.
Investigation of the stall delay of a 5kW horizontal axis wind turbine using numerical method
Authors: Hsiao Mun Lee  , Leok Poh Chua
Published: May 2017

In this paper, a three-dimensional (3D) computational fluid dynamics (CFD) model is constructed to test a 5kW horizontal axis wind turbine HAWT that was designed using BEM method. It is found that the power coefficient of 0.38 determined by the 3D CFD model is higher than 0.34 obtained by the BEM method. The difference should be due to the stall delay in the rotation flow field of the wind turbine model, which was confirmed by the simulation results that the flow remain attached to the blade surface when wind velocity has reached 20m/s. The behaviours of the flow separation were also investigated under different wind speed in order to improve the performance design of the wind turbine blade.
Comparative study of the opportunity to use Renewable Energy Sources to supply Residential Consumers
Authors: F. D. Surianu  , I. Borlea  , D. Jigoria-Oprea  , B. Lustrea
Published: May 2017

Taking into account the directions of the European Union, concerning the increasing role of renewable power sources for supplying loads and reduction of CO2 emission, this paper presents details of the technical and economic characteristics of the main types of renewable power sources. It also analyzes the feasible technologies to ensure the supply of power to the residential areas using different renewable power sources. Using HOMER, the program meant for the optimal choice of power sources that supply electric loads, the paper has made a comparative technical and economic analysis of the supplying possibilities of a micro power system, using renewable power sources: wind, biogas, PEM fuel-cells and photovoltaic panels.
Performance analysis of Euro-zone energy companies
Authors: Valdir de J. Lameira  , Silvano Vergura  , Osvaldo L. G. Quelhas  , Roberto G. Pereira
Published: May 2017

This investigation is focused in answering if the location and sector of activity of energy companies located in the Euro-zone impact the performance of these companies. A database of 18 largest energy companies in the Euro-zone between 2005 and 2009 was constructed. The method of linear regressions with panel data was applied. Results get posible to infer that oil and gas sector have the highest returns and the location does not impact the economic and financial performance of energy companies.
Energy conservation using high-efficiency electric motors
Authors: Sergio Roberto Jardim  , Gilmar Barreto
Published: May 2017

The current policy to keep and rationally use energy in Brazil is focused on allocating energy resources efficiently and preserving the environment. Thus, understanding the legislation and the problems tied in with inadequate consumption of energy promotes creating basic parameters and formation of industrial policies to keep energy efficiently. Moreover, it offers using better the available resources at a lower cost.
Given the current policy of Conservation and Rational Use of Energy in Brazil, which aims at the efficient allocation of energy resources and preserving the environment, understanding the Legislation and the problems related to inadequate consumption of energy promotes the creation of basic parameters as well as industrial policies of conservation and energy efficiency that will promote a better use of available resources at lower costs. We can say that of all the motors used in industry, the electric induction motor is the most used, as it combines the advantages of using electric power, low manufacturing costs, ease of transport, cleaning, simplicity in control and mechanical robustness with its simple construction, versatility to adapt to various types of loads and better performance. The purpose of this study is to highlight this theme and its contributions.
CFD simulations for investigating the wake states of a new class of tidal turbine
Authors: Mulualem G. Gebreslassie  , Gavin R. Tabor  , Michael R. Belmont
Published: May 2017

The interest of tidal energy exploitation is increasing in recent years promoting the need for development of efficient tidal turbines. This paper investigates the wake states of energy extraction by a new tidal turbine design, the Momentum Reversal Lift (MRL), developed by Aquascientific Ltd with a different method of tidal turbine modelling (body force) using an open source computational fluid dynamics (CFD) code, OpenFOAM.
The body force CFD model results showed better turbulent patterns downstream of the turbine showing its quality compared to porous disc method which has been used for tidal turbine modelling. The simulations on a single MRL device showed that the wake recovers into 94% of the free stream at 20D downstream of the turbine. The performance of a downstream turbine simulated with 20D spacing was reduced by almost 7.17% due to the energy shadowing created by the upstream wake. Thus, it is necessary to have at least 20D turbine spacing to maintain more than 92% of the performance of an isolated turbine.
Paper Certificate Energy and Greenhouse Gas Analysis for Biogas Power Plants
Authors: Wolfgang Bauer  , Stefan Bauer  , Thomas Bauer
Published: May 2017

In order to assess the efficiency of an alternative power source and to provide a meaningful comparison with fossil fuel based power sources, a complete accounting of all energy input and output streams, as well as all greenhouse gases, is necessary. We present this analysis for a 1.45 MW (0.71 MW electrical) biogas power plant operating with 70% corn silage and 30% cow dung feedstock. We find net energy ration of 8.0, a net efficiency of 1.2% of converting solar energy into electricity and usable heat, and that only 16 g CO2 per kWh are generated in the process. If all greenhouse gases are considered, our process even actively reduces the total greenhouse gas load on the atmosphere. In terms of producing transportation biofuels our plant provides 3.8 times more yield per hectare than bioethanol plants.
Effect of Superconducting Fault Current Limiters on Successful Interruption of Circuit Breakers
Authors: M. Firouzi  , S. Aslani  , G. B. Gharehpetian  , A. Jalilvand
Published: May 2017

The penetration of DG systems in distribution systems can result in the increase of the short circuit current level. The application of the fault current limiter (FCL) would not only decrease the stress on network devices, but also can offer a connection to improve the reliability of the power system. There are various types of FCLs, which are made of different superconducting materials and have different designs. There are several kinds of SFCLs, which can be classified in three types such as the resistive type, the inductive type and bridge type SFCL. In this paper, the transient recovery voltage (TRV) analysis, based on the electromagnetic transient program (EMTP), is used to investigate the behavior of the each three types SFCL installed in an electrical distribution grid. Simulation results show that the TRV can be damped in the presence of the resistive and bridge type SFCL during fault clearing period.
Paper Certificate Frequency Variations of Power System Due to Switching of Renewable Energy Sources
Authors: W. L. Fuchs  , E. F. Fuchs
Published: May 2017

Power  systems  mainly  containing  intermittently  operating   renewable   sources   require   load/frequency   control   which  is  performed  at  the  AC  transmission  and  distribution  levels.  This  frequency  control  can  be  achieved  by  employing  short-  and  long-term  storage  plants  buffering  and  complemen-ting  renewable  energy  sources.    A  representative  grid  consists  of  a  natural-gas-fired  plant  serving  as  frequency  leader,  long-term storage plant, wind-power farm with associated short-term storage  plant  for  energy  buffering,  photovoltaic  farm  with  associated  short-term  storage  plant  interconnected  by  a  long  transmission  line  to  two  load  circuits.    Transient  analysis  is  performed  with  Mathematica  solving  the  differential  equation  system   for   frequency   variation.   Power   flow   through   the   transmission  line  is  limited  by  its  impedance.  The  long  trans-mission  line  must  be  segmented  to  achieve  stability  and  the  voltage must be controlled between segments of an 800km line. The   renewable   plants   must   be   operated   together   with   the   storage  plants  in  order  to  minimize  frequency  variations  by  smoothing  the  power  output  of  renewable  plants,  achieving  a  step-wise control of the transmission-line power.
Control Strategies for a Power Electronic Based Fault Current Limiter (FCL) in No-Fault Operation
Authors: Manuel Weiland  , Gerhard Herold  , Christoph Hahn
Published: May 2017

Fault current limiters (FCL) in electrical power systems offer the opportunity to reduce short-circuit stresses to the system in the case of faults. But as electrical power systems are normally operated without faults most of the time, FCLs must not have negative effects during these periods of normal operation. The FCL investigated in this paper is based on a 6-pulse current converter. As every other current converter this type of FCL can introduce additional system perturbations in form of higher harmonics. The aim of this work is to develop appropriate strategies to control the FCL in a way that virtually no additional system perturbations are introduced by the FCL under normal no-fault conditions. In electrical three-phase systems this means simply, the controller has to provide sinusoidal current waveforms.
Control Design for a Power Electronic Based Fault Current Limiter (FCL)
Authors: C. Hahn  , M. Weiland  , G. Herold
Published: May 2017

This paper shows a solution for controlling shortcircuit currents of a power electronic based Fault Current Limiter (FCL). A model for control design of three-phase short-circuit currents will be presented. A way of limiting the maximum aperiodic short-circuit current is derived with special regards to the stability of the entire system. Control designs of single- and two-phase shortcircuit currents are shown in the paper as well as a method of fault type detection.
The Sampling Theorem based Methodology for Harmonics Analysis
Authors: P. Bokoro  , J. Pretorius  , M. Case
Published: May 2017

This paper investigates the validity of the sampling theorem in the analysis of supply side line current harmonics as applied to 6-pulse AC-DC thyristor converters. The common pattern of the percentage harmonic factor, for the converter characteristic harmonic current, per incremental change of the thyristor firing angle is used as the basis of the study. The RMS values of the peak amplitudes of the characteristic harmonic currents induced in the input-phase of the converter supplying a DC motor are described in terms of the sampling theorem equations and further evaluated in terms of their respective individual harmonic contributions as the thyristor firing angle is changed. The MatLab/Simulink package is also employed to simulate the forward drive speed control operation of a DC motor using the 6-pulse AC-DC thyristor converter. However the percentage harmonic factor trends observed in the sampling theorem method appear to be generally increasing which is in contradiction to the MatLab/Simulink produced trends.
Temperature of Wood Char Particles Burning in a Fluidized Bed Reactor
Authors: N. Tomé  , N. Rangel  , C. Pinho
Published: May 2017

In the present work it was studied the fluidized bed combustion of char particles made with wood of Mozambican origin to find out the evolution of the particles temperature during the combustion process. Samples of wood species Afzelia quanzensis and Pterocarpus angolensis were carbonized at 850 ºC in a nitrogen flow. Afterwards some of these char particles with sizes in the 9 to 13 mm range were burned in a bubbling fluidized bed, while at the same time their interior temperatures were measured. From the experiments, it was found that for these chars fragmentation was absent and that the measured temperatures with a thermocouple inserted into the particles was similar to the values that were obtained by means of an energy balance carried out at the surface of the particle.
A theoretical study on third generation photovoltaic technology: dye-sensitized solar cells
Authors: J. Gong  , K. Sumathy
Published: May 2017

A numerical model has been developed to investigate the performance of dye-sensitized solar cells (DSSCs) under extreme weather conditions. The main purpose of this work is to simulate the temperature influence on the overall efficiency of DSSCs with a consideration of the voltage loss at titanium dioxide (TiO2 )/ transparent conductive oxide (TCO) interface. Appropriate simulation input parameters are chosen to reflect the extreme winter weather conditions of Fargo, North Dakota. It is found that at the temperature 250 K (ca. -20 °C), the maximum power output is about 23 W/m2 which is about 50% lower than the value at 340 K (ca. 70 °C). The study reveals that low temperature conditions have serious detrimental effects on the DSSCs’ performance.
A Simplified Life Cicle Assessment applied to a coupled Solar and Eolic street ligh
Authors: J.-L. Menet
Published: May 2017

The idea of a street light which would be independent of the power grid and which would be in the same time ‘ecological’ is to be demonstrated. To answer this question, the environmental impacts of a Solar and Eolic street light called SOLEOL are quantified using a simplified Life Cycle Assessment (i.e. using simplified inputs for the photovoltaic system and the generator).
The chosen Functional Unit is: ‘the lighting during 25 years with LED lamps with a power of about 2500 lumens’. The data corresponding to the Life Cycle Inventory are divided into the classical four phases of the Life Cycle Assessment (LCA) methodology.
The environmental impacts are valuated and aggregated; then a comparison is made with a conventional street light. It is shown that the SOLEOL and the conventional street lights are generally at the same level, except for the non-renewable energy consumption where the SOLEOL is better for the environment, and for aquatic toxicity where the SOLEOL street light has a greater impact.
This study shows that a street light said to be environmentally friendly could have in fact a greater impact on the environment, but in our case, and even if no optimization has been made on it, the SOLEOL street light is honorably placed relatively to conventional street lights.
Experimental and theoretical analysis of thermal solar collector systems for DHW in Northern Italy
Authors: Arboit, M.  , Toniolo, J.  , Ghafoor, A.  , Fracastoro, G.V.
Published: May 2017

The aim of this work is to describe a methodology for the in situ experimental evaluation of the performance of Solar Collector systems for Domestic Hot Water production (SCDHW), which are by far the most common use of solar thermal collectors. In situ monitoring of ten SCDHW, including DHW storage and back-up heating system led to an estimate of yearly performance, which has been compared with results from simulations performed using widely spread commercial software and f- chart method. Measurements were carried out for at least 20 days for each plant, with sampling rate of ten minutes. As DHW demand was unknown, it was assumed from SC area. Results show that the solar collector’s area was systematically oversized respect to actual DHW needs, resulting in measured lower efficiency (around 30%) than calculated by commercial software. Reducing DHW needs, measurements and calculations produced closer results.
Analysis and Energetic Characterization of Low-Power Grid-Connected Photovoltaic Systems
Authors: António P. Martins  , Domingos M. Carvalho
Published: May 2017

This paper discusses some of the most important Photovoltaic (PV) systems characteristics related to its global efficiency like MPP tracking efficiency, static efficiency, conversion efficiency as well as the Euro efficiency. The losses models of the power semiconductors constituting the Power Electronics (PE) subsystems as well as the models of transformers and DC and AC cables are reviewed. Three topologies are selected, representing the PV market and simulation results are discussed. Given the importance of the global efficiency of an installation for the owner, recorded field results with the same systems are presented. The main conclusion is that the global efficiency of a PV installation depends not only on the PE subsystem, with or without isolation transformer in the low or high-frequency stages, but also on the DC and AC conduction losses, and on the distance of the installation to the coupling point to the electric grid.
Innovative Construction Component
Authors: A. Michael  , M. Eftychi  , F. Bougiatioti
Published: May 2017

This paper presents the design process for an innovative modular brick unit, which was based on the principles of bioclimatic and environmentally-friendly architecture.
The design aims at creating an architecturally appealing component, which at the same time can fulfil various bioclimatic functions depending on the prevailing climatic conditions and the building requirements. The presented design proposal was a winning entry at the international architectural competition “Brick-stainable: Rethinking the Brick”, organised by Potomac Valley Brick.
Construction Design and Sustainability in Architecture: Integrating Environmental Education in the Architectural Studies
Authors: A. Michael  , M. C. Phocas
Published: May 2017

Based    on    the    modern    interpretation    of    architectural  education  at  university  level,  architectural  design  is  developed  within  the  multidisciplinary  nature  of  the  area,  at  various  levels  of  analysis,  at  all  scales  of  the  project.  The  present paper underlines the necessity of integrating technology courses with design and sustainability issues. In clarifying this, the    respective    pedagogical    approach,    followed    at    the    Department  of  Architecture  of  the  University  of  Cyprus,  in  the  courses of construction in timber, reinforced concrete and steel, as  well  as  in  the  main  architectural  design  coursework  with  emphasis in technology, is discussed. As   regards   the   building   technology   component   within   the   architectural   education,   the   application   of   the   respective   technical  knowledge,  obtained  through  lectures  and  exercises,  in a design project is of major importance. The design project is organized  within  a  studio  or  micro-studio,  and  becomes  the  major  assignment  of  each  respective  construction  course.  A  necessary component for a successfully-integrated design is the iterative  realization  of  an  architectural  aim,  the  design  vision  that  binds  every  element  of  the  design  of  different  scales  together. In this way, construction design substitutes the merely more  empirical  act  of  “architectural  design”  throughout  the  integration process. The  sustainability  component  of  the  designs  in  the  studio  or  micro-studio refers to the bioclimatic, construction and energy-efficient   design.   The   investigation   and   application   of   all   aforementioned      aspects      ensures      the      comprehensive      environmental  approach  in  the  creation  of  the  built-up  spaces,  underlying  at  the  same  time,  the  importance  of  integrated  design in the studio or micro-studio.
Feasibility study of biogas in CHP plant for a pig farm
Authors: F. Patania  , A. Gagliano  , F. Nocera  , A. Galesi
Published: May 2017

Cogeneration, or the Combined production of Heat and Power (CHP), is being promoted at EU level as a way of reducing green house gas (GHG) emissions from traditional power plants.
For a long time, CHP systems have been used successfully in industry but it can be developed across numerous market sectors, including zootechnics farms. Currently with the rapid global economic change and the increasing needs for environmental sustainability it is timely to review pig farm heat and electrical power options to reduce costs and optimize environmental outcomes. This paper describes a feasibility study of biogas CHP plant in a medium pig farm in Italy. Biogas, produced by pig manure, is burned in CHP system to satisfy the demand of electricity and heat. Results illustrate how the utilization of gaseous product from pig farm effluent (biogas) as fuel for heat and power generation can reduce both energy cost and CO2 equivalent GHG emission in the environment.
Performance of Power-Line-Signaling Based Detection Algorithms for Islanding Protection of Distributed Generators in Interharmonic Polluted Systems
Authors: H. Jouybari-Moghaddam  , G. B. Gharehpetian  , S. H. Hosseinian
Published: May 2017

Recently, a new islanding detection scheme based on power electronic signaling technology has been proposed in the literature. By broadcasting a signal on the distribution feeders from the substation to the down-stream DGs, the absence of the signal at the DG site will be a sign of islanding. The scheme is more reliable than regular local detection techniques while it costs much less than transfer trip schemes. As the checking of the signal continuity is done via signal detectors, performance analysis of implemented detection algorithms is one of the main concerns. Since, the scheme relies on distortion broadcasting, our purpose is to answer the first question arises i.e., `` Is it a reliable scheme for DGs located at industrial areas that are rich in harmonics and interharmonics? ". Results show that for spectral based detection algorithms, more selective thresholds must be set in case of excessive interharmonic pollutions.
Comparison of Multicarrier PWM Strategies for Five-level Z-Source Diode-Clamped Inverter for On-Grid Renewable Energies Applications
Authors: M. Nasiri  , G. B. Gharehpetian  , J. Milimonfared
Published: May 2017

Multilevel Z-source inverters have been proposed as a solution for HV applications. This type of inverters decreases the Total Harmonic Distortion (THD) and has a good performance for different applications such as Flexible AC Transmission Systems, power quality improvement and connecting renewable energy resources to the network. This paper compares several alternative carrier disposition PWM strategies for a five-level Z-source diode-clamped inverter. These strategies are simulated in MATLAB/Simulink. The simulation results illustrate that using Phase Disposition (PD) method, the voltage THD decreases considerably. Also, Alternative Phase Opposition Disposition (APOD) method increases the voltage magnitude more than PD method. Both methods can be effectively used for connecting renewable energy sources to the power grid.
Study of Shunt Active Power Filters Applied to Three-Phase Four-Wire Systems
Authors: E. J. Acordi  , L. B. G. Campanho  , S. A. O. Silva  , C. B. Nascimento  , A. Goedtel
Published: May 2017

This work presents a study of shunt active power filters (APFs), which are implemented by means of both fourlegs and three full-bridge voltage source inverter (VSI) topologies. These topologies are applied in three-phase four-wire systems for reactive power compensation and harmonic current suppression generated by nonlinear loads. The compensation reference currents used in both APFs are extracted from the synchronous reference frame (SRF) based controllers. A mathematical analysis of the four-legs and the three full-bridge topologies are presented in order to obtain the model in state space and the transfer functions of each system, allowing to set the proportional-integral (PI) gains used in the current controllers. Simulation results are presented in order to evaluate the performance of the APFs approaches.
Modeling and Reactive Power Control of Wind and Fuel Cell Technologies in Distribution Networks
Authors: M.M.A.Mahfouz  , Mohamed A. H. El-Sayed
Published: May 2017

An integrated scheme of wind and fuel cell renewable energy technologies in distribution networks for electrical energy generation from renewable resources is digitally simulated and presented in this paper. The integrated system has four key subsystems or components to supply the required electric loads. The first subsystem includes the renewable generation sources from Wind turbines and fuel cell stacks. The second represents the added inverter between the Fuel cell collection DC bus and the point of common coupling PCC with the AC distribution network. The third device is the static synchronous compensator STATCOM to provide the required reactive power for voltage regulation at the bus of PCC. The fourth subsystem comprises mainly of two PI controllers. The first controller main function is to regulate the hydrogen flow to the fuel cell, while the second one is used to control the switching action of the STATCOM converter for injecting the required reactive power. The integrated system and the associated subsystems are fully validated for efficient operation under normal or fault conditions using the Matlab/Simulink/SimPower software environment.
ENERCARE
Authors: Miguel Lagares-Lemos  , Enrique Jiménez-Domingo  , Ángel Lagares-Lemos  , Juan Miguel Gómez-Berbís
Published: May 2017

Households, factories, office buildings and communities can reduce their energy consumption, while maintaining the same level of activity and comfort, by identifying and avoiding unnecessary energy waste. Governments around the world are taking initiatives in this direction and also international coordinated initiatives such as the future ISO 50001.
To support these plans, the general goal of ENERCARE project is to design a new open information platform built on customizable, adaptive and open service-oriented architecture, providing connectivity to the energy grids and information to the users.
ENERCARE will provide an innovative platform for the development of a key piece in a new generation suite of Smart Grid products. Through the spread of services on energy management, will encourage more energy conservation at demand side and will contribute to the achievement of lowcarbon society to come.
ENERCARE will work to increase the social awareness of the citizens in saving energy and the improvement in new and more efficient habits triggered by IT solutions.
Strategies to Reduce the Use of Fossil Fuels
Authors: J. Paraszczak  , K. Fytas
Published: May 2017

Mining industry is a substantial consumer of the energy indispensable to power mining and mineral processing equipment and processes. As more and more mine operations move to remote locations, the access to reliable, secure and environment friendly energy sources becomes a key concern. At present, a great majority of remote mines relies heavily on diesel fuel that has to be transported over long distances. In this context, some of the renewable energy sources such as for example wind power or solar energy seem to provide potentially interesting and viable alternatives. Mine operations however, have a very particular character, much different from other industries and from other potential applications of renewable power sources. This paper presents operational conditions of some mining operations, particularly those in remote regions, in the context of their energy needs. The authors analyse current and future capacities to decrease a reliance of remote mines on conventional fuels and energy. The paper analyses and discusses also the conditions to be met by alternative energy sources so that they might become a viable alternative for remote mining operations.
Digital controller for an isolated Step-Up DC-DC converter based on three-phase high-frequency transformer for grid-connected PV applications
Authors: R. D. O. Reiter  , J. R. Pinheiro  , A. Péres  , L. Michels  , S. V. G. Oliveira
Published: May 2017

This paper presents the control system design of a DC-DC converter with a three-phase high frequency transformer for dual-stage grid-connected PV applications. This converter is designed to be used in the input stage of parallel single-string PV arrangements for residential applications. The proposed control strategy uses a maximum power point tracking algorithm with an outer voltage loop and an inner current loop. The current loop includes a resonant control action in order to eliminate the 120Hz ripple of the DC bus in the PV modules. Simulation results are presented to validate the proposed control strategy.
Frequency Stability Analysis of a Dynamic Wind Park in an Integrated Power Grid
Authors: L. Thurner  , S. Liu
Published: May 2017

In spite of rapidly growing wind power capacities, wind power still only accounted for a small fraction of the electric power supply in the last years. Therefore, research in the area of wind power was mostly focused on the wind generators and wind parks themselves, aiming to maximize their efficiency and stability. But as the weight of wind power grows, their influence on power systems cannot be neglected anymore. That is why recent research like [1], [2] or [3] studies the effects that wind parks have on the dynamic power grids they are connected to. Continuing in this direction, we implement a simulation model of a power grid including a wind park and study its dynamic behavior with varying wind speed. The influence of certain parameters like transmission line length, rated power of the wind park or control depth on the frequency stability in the power system are studied and analyzed. Furthermore, a control scheme to integrate the wind park into the grid frequency control is implemented.
Grid-connected PV-systems Joule design using Evolutionary Strategies
Authors: Daniel Gómez-Lorente  , Enrique Alameda-Hernández  , F. Aznar Dols  , M.J. Mercado-Vargas  , M.J. Mercado-Vargas  , A. Espín  Estrella
Published: May 2017

This paper shows how to compute the optimal distribution of the main elements of a photovoltaic (PV) plant with trackers connected to the network, to reduce some of the losses that occur in these facilities. In particular, the objective function of the proposed optimization process is the minimization of Joule losses that occur in electric conductors. To solve this problem, genetic algorithms (GAs), implemented in Matlab, have been used. Specifically the steady-state GA and the generational GA, which from random initial solutions, possibly far from optimal, will evolve into solutions that are increasingly closer to the desired optimum. Results have been very satisfactory, since all proposed examples have reduced by more than 50% electric
Performance analysis of two industrial dryers (cross flow and rotary) for ligno-cellulosic biomass desiccation
Authors: Nadia Cairo  , Gianpiero Colangelo  , Giuseppe Starace
Published: May 2017

Artificial drying, using industrial devices (dryers), helps to reduce the residual humidity content in biomass in a relatively short time. Convection is one of the most common mode of drying (referred to as direct drying). Heat is supplied by hot air/gas flowing over the surface of the solid. The heat for evaporation is supplied by convection to the exposed surface of the material; the evaporated humidity is carried away by the drying fluid. Indirect dryers (working by conduction) are more appropriate for particulate and granular materials or for very wet solids; while radiative dryers use various sources of electromagnetic radiation with wavelengths ranging from the infrared to microwaves.
In this work, two mathematical models of cross flow and rotary dryers (both convective dryers) have been proposed. Both dryers treat wood chips. The two models allow to calculate the thermal efficiency and residence time of wet solid wood chips, as a function of the residual moisture content, as well as the analysis of the behaviour of the outlet wet solid and drying gas, in consideration of the dryer length and of the feeding material conditions in the dryer. The models have been developed in the Mathcad software environment.
2D Vibration based MEMS Energy Harvester
Authors: Sehwan Kim  , Kukjin Chun
Published: May 2017

Electrostatic energy harvester for two axis vibration is developed. It was fabricated by using silicon-glass anodic bonding and deep silicon etching. The device which generates energy from only one directional vibration has much different resonant frequency for each direction. To gain energy from two or more directional vibration the structure was designed to have equal resonant frequency along the x, y-axis by symmetric spring-mass structure. When the direction of ambient vibration is changed from x-axis to y-axis, the device still generates equal amount of energy. Resonant frequency of the structure is 191 Hz along the x-axis vibration direction. The device size is 9.0 mm×9.0 mm×0.6 mm. Vibration of which the acceleration is 1.2 m/s2 and the frequency is 191 Hz generates 0.73 µW/cm3 . Although vibration direction is not matched, power is generated more than 0.2 µW/cm3 at resonant frequency.
Geothermal energy: Present use, Resources and Technology
Authors: M. R. Duque
Published: May 2017

In this work we use a data-base compiled by the IGA to examine the increase of geothermal energy use in recent years. We speak about electricity produced by different plant types and direct uses of geothermal fluids. We can conclude that the use of geothermal energy has tended to increase in recent years. According to the IGA, there are 233 geothermal plants planned to be in operation in the coming years. The direct use of geothermal fluids is increasing especially the use of geothermal heat pumps.
The last part of the work is dedicated to geothermal resources and future research related to this subject. We discuss different problems related to each type of resource and present the benefits that their exploration can bring to humanity, especially those related to air pollution.
An extended EMC study of an electrical powertrain for transportation systems
Authors: B. Chand  , J. Keghie  , S. Dickmann
Published: May 2017

The change from conventional to electric drives in transportation systems is forced by the shortage of gasoline and the environment protection. Electric drive systems are a challenge for the manufacturers. The electrical powertrain can not only be exposed to interferences, it may also emit interferences into components and communication cables in the vicinity. These can be a high risk for the drive system and for the passengers, when the electric drive is used for human transport. This paper presents an EMC study of an electrical powertrain for transportation systems. A brief summary of the interferences at the unshielded high-voltage cable (HV-cable) is given. The analysis of the influence of position variation of the communication cable to the unshielded HV-cables is studied. Different cheap shielding variants are analysed and compared to full shielded HV-cables. Furthermore, different optimizations have been added to the test setup.
Power Control of a Wind Energy Conversion System based on a Doubly Fed Induction Generator using RST and Sliding Mode Controllers
Authors: A.BELABBES  , B. HAMANE  , M.BOUHAMIDA  , A.DRAOU
Published: May 2017

In this paper, a power control study analysis of a wind energy conversion system (WECS) based on a doubly fed induction generator (DFIG) connected to the electric power grid is presented. The main objective of this work is to compare the energy production unit performances by the use of two types of controllers (namely, Polynomial RST and Sliding Mode (SM) Controllers) for the WECS control in terms of instruction tracking and robustness with respect to the wind fluctuation and the impact on the quality of the energy produced. A vector control with stator flux orientation of the DFIG is also presented to control the active and reactive powers between the stator and the network. To show the effectiveness of both control methods performances analysis of the system are analyzed and compared by simulation and results included in this paper.
Development of Solar Powered Boat for Maximum Energy Efficiency
Authors: Juraci Carlos de Castro Nóbrega  , Andrej Rössling
Published: May 2017

The present paper shown a work in research and development of a small solar boat design, this work has been developed in Anast/ULG-Belgium as reference for Post-graduate degree in Naval Architecture. The development of a methodology of simple calculation, step by step, for solar boat is shown here, taking in account the use of clean energy, minimum weight of the boat and minimum price of fabrication, for this has been considerate: boat weight; sheet specification; material utilized; appropriate propulsion; necessary quantity of solar panels; quantity of batteries; adequate engine; until to the final commercial price. The Nautilus is a solar powered pleasure boat and basically designed for day-and weekend-trips.
Pressurized concentrated solar power receiver designed to operate with closed Brayton cycles
Authors: R. Ferreiro Garcia  , R. Borras Formoso  , A. DeMiguel Catoira  , J. Romero Gomez
Published: May 2017

Parabolic through and parabolic dish concentrators (PDC) followed by a volumetric receiver is proposed, studying the performance behavior of a closed Brayton cycle (CBC) operating with He and N2. A pressurized gas (helium, nitrogen) circulates along the volumetric receiver capturing the concentrated thermal solar energy which is converted into mechanical energy by a CBC. The overall efficiency of the plant (PC-Receiver + CBC) is being computed under variable parameters to determine the operating conditions for which efficiency is acceptable. As consequence of the proposed analysis, it is concluded that direct coupling between volumetric receiver and thermal engine renders high efficiency while avoiding a heat exchanger.
Identity in Changing Context: Factors of losing Identity in new developed part of the city of Famagusta, North Cyprus
Authors: Nia Hourakhsh Ahmad , Suleiman Yousif Hussien
Published: May 2017

Historical cities due to its magnificent building in its context have a tremendous influence on the formation of city identity, which is created through the interaction of natural, social and built elements. Unfortunately, modernization after the industrial revolution couldn’t adapt itself to the vernacular area, owing to the fact that cities began to lose their identity and sense of belonging to the environment. The new technology of construction lets the cities to expand itself outside, but in this transformation, some factors which have an influence on the identity of the city have been forgotten. In this research, it is aimed to analysis Physical and social factors which are causing the loss of identity in the city of Famagusta (Gazimagusa). Both qualitative and qualitative methods have been used in this research and the adopted techniques are personal observation, sketches, and comparing new development part of the city with the traditional part. The research will try to answer the question of why urban sprawl could not maintain the identity of the city of Gazimagusa?. This research revealed that Globalization by neglecting historical housing principles is the main factor which threatening the identity of the city.
The inspiration of Bauhaus principles on the modern housing in Cyprus
Authors: Aziz Amen Mustafa
Published: May 2017

Modern architecture developed more than a century ago to find solutions suitable to solve the new concerns of the industrial revolution that changed the social idea of the world in all aspects. Bauhaus school which established by Walter Gropius in 1919 adopted too many principles and ideas that were totally new to the architectural concept and theory at that time; their principles started from Simplicity, Angularity, Abstraction, Consistency, Unity, Organization, Economy, Subtlety, Continuity, Regularity, and Sharpness. Those principles affected the architectural world and found its way through many applications in different parts of the world. The unlimited space or the international space that had a significant influence on the architecture space and form as well as the introduction of the new material, the anti- decorating, and Platonic forms had worked to reconstruct the architecture in the world. Cyprus as an island close to the sources of the movement got the influence from the modern movement. The study will concentrate on Efruz Housing which designed by Ahmet Vural, who developed the project in the 60th of the last century. The aim of the research is to find the relationship and effects of Bauhaus school in Cyprus through studying and analyzing some of Ahmet Vural works. The methodology will depend on a comparison with the traditional housing that preceded Mr. Vural work and how the Modernism changed the main features of the housing on the Island.
Establishing and maintaining the National Vaccination Register in Finland
Authors: Baum Ulrike , Sundman Jonas , Jääskeläinen Susanna , Nohynek Hanna , Puumalainen Taneli , Jokinen Jukka
Published: May 2017

Computerised, population-based vaccination registers are valuable tools for assessing the vaccine uptake and impact in populations. However, reliable impact assessment is only possible if the data quality can be reviewed and monitored continuously. This report describes the establishment and maintenance of the National Vaccination Register (NVR) in Finland. Currently, the NVR covers nationwide records of vaccinations given within the frame of the National Vaccination Programme since 2009. All vaccinations registered in the NVR contain a record of the personal identity code, the administered vaccine, and the date of vaccination. The vaccine lot number is the key component for recording and identifying vaccinations, because of its broad availability across patient information systems and its importance in vaccine safety monitoring. Vaccination records are accumulated and updated daily into the NVR, and their completeness is monitored monthly to assess deficiencies in data entry and data collection. Additionally, an alert system reports unexpected changes in data accumulation prompting the validation of observed changes in vaccination coverage. The presented process documentation may serve as basis to improve the design and quality of other vaccination or healthcare registers and aims to inspire the set-up of vaccination registers in those countries which still do not have one.
Komponentenbasierte Software-Technologie in der Produktionstechnik
Authors: Kreppenhofer Dietmar , Langer Tino
Published: May 2017

Kurzfassung

Software ist zu einem wesentlichen Erfolgsfaktor in vielen Maschinen und Anlagen geworden. Der wachsenden Dynamik und Komplexität von Produktionsprozessen und Anlagentechnik können die meisten der existierenden Software-Systeme nicht folgen, da sie konzeptionell nicht oder nur ungenügend auf permanente Anpassungsfähigkeit vorbereitet sind. Durch den zielorientierten Einsatz moderner Software-Technologien, sowohl während der Entwicklung als auch im Betrieb, kann bei notwendigen Änderungen in der Produktionstechnik die zugehörige Software aufwandsarm an die neuen Bedingungen angepasst werden. Neben Modularität und Flexibilität stehen vor allem Stabilität und Sicherheit von Software-Anwendungen im Mittelpunkt. Ganz besonders treffen diese Forderungen auf Applikationen zur Verarbeitung sensibler Produkt-, Prozess- und Anlageninformationen zu. Dieser Beitrag geht auf einige Aspekte im Rahmen der Software-Entwicklung am Beispiel eines im Fraunhofer IWU entstandenen Systems zur Echtzeiterfassung, Verwaltung und Auswertung von maschinen- und anlagenbezogenen Produktqualitätsdaten als Teil eines Produkt-Traceability-Systems ein.
Hochdynamische Werkzeugmaschinenstrukturen und -komponenten
Authors: Neugebauer Reimund , Hipke Thomas , Ihlenfeldt Steffen
Published: May 2017

Kurzfassung

Mit dem Ziel, die Vorteile und insbesondere die hohe Dynamik von Parallelkinematiken auch auf Großwerkzeugmaschinen zu übertragen, entstand das Konzept einer Hybridkinematik für den Großwerkzeug- und Formenbau. Die prinzipielle Lösung ist dadurch gekennzeichnet, dass eine serielle Grundkinematik eine Parallelkinematik-Bearbeitungseinheit trägt. Mit einem solchen Aufbau kann die Dynamik der Rundachsen verbessert und die mittlere Vorschubgeschwindigkeit gegebenenfalls durch Achsüberlagerung weiter gesteigert werden.