By Topic

Environment and Electrical Engineering (EEEIC), 2012 11th International Conference on

Date 18-25 May 2012

Filter Results

Displaying Results 1 - 25 of 209
  • Single-point measurement localization of prevailing harmonic sources in a power system

    Page(s): 1 - 6
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (707 KB) |  | HTML iconHTML  

    The paper deals with higher harmonics in a power system. The aim of the paper is to present a review of ideas of single-point measurement localization of prevailing harmonic sources in a power system. Knowledge about the location of the harmonic sources in a power system is useful to control harmonic levels at a power system. These knowledge is also useful to solve disputes between utilities and customers. In the paper, ideas of localization of prevailing harmonic sources in a power system based on analysis of components of the voltage or current as well as based on analysis of the power flows at the point of common coupling are described. For each of the mentioned ideas, theoretical background, notes on practical realizations and discussion of features are presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Medium-term generation scheduling in electric power systems

    Page(s): 7 - 12
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (716 KB) |  | HTML iconHTML  

    The paper considers specific features of problem statement for the medium-term generation scheduling in a wholesale electricity market environment. An approach is suggested to solve the problem on the basis of bilevel optimization models. Such models take into account possible distortion of data on economic parameters of generating units and further centralized scheduling of electricity generation by the System Operator. The bilevel models calculate the levels of locational marginal prices in the wholesale market. The calculation of prices is necessary to take account of the price elasticity of demand and to analyze the profit of electricity suppliers. To simulate the competitive behavior under the conditions of oligopoly market, the authors determine the equilibrium state, at which electricity suppliers have no incentive to change their decisions unilaterally. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Condition monitoring & fault diagnosis system for Offshore Wind Turbines

    Page(s): 13 - 17
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (896 KB) |  | HTML iconHTML  

    Due to the technological development, the electronic power progress and economic stake, through the use of Wound Rotor Induction Motor (WRIM) has taken more and more places in different domains (transport, energy production, electric drive..,) thanks to their robustness, efficiency and lower costs. Despite the performed work researches and the improvement that has been brought, these machines still remain the potential seats of failures both in stator and rotor levels. Consequently, WRIM faults detection is currently one of the centers of interest of several researches of both academic and industrial laboratories. In fact, this article addresses this problem by the use of Principal Components Analysis (PCA) for faults detection in Offshore Wind Turbine Generator (OWTG). An accurate analytic modeling of healthy and faulted OWTG is suggested to perform the data matrix needed for PCA method. Tests were achieved using a numeric simulator on Matlab/Simulink software. Analysis of OWTG simulation proves the efficiency of PCA method. Several simulation results will be presented and discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimal demand response program for the best load profile reformation based on an adaptive technique in smart grids

    Page(s): 30 - 35
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (7 KB) |  | HTML iconHTML  

    Smart grids are integrated communications and power system infrastructures to improve the efficiency, reliability and safety of power deliveries and its usages. In this paper, Time of Use (TOU) programs in smart grids is studied. In this regard, Real Time Pricing method (RTP) has been developed using multi objective load models. Also, the effects of smart grids on demand curve have been simulated by different scenarios. Also, elasticity criterion in this method is optimized, and after that the best elasticity value is achieved. Also, Iran's national grid has been selected to analyze the effects of real time pricing in smart grid environments on load curve. Meanwhile, the results have been compared with TOU programs for better presentation of proposed method and finally excellent performance of the presented technique will be shown. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Using a fixed point method to compute the parameter space distance to the surface of constant critical energy

    Page(s): 298 - 302
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (195 KB) |  | HTML iconHTML  

    Power system voltage security assessment is generally applied by considering the steady-state stability surface. However, as seen in the literature, random perturbations can drive the system away from stable operation, long before the steady-state stability surface is reached. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Simulation of a overhead power line

    Page(s): 303 - 307
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (880 KB) |  | HTML iconHTML  

    Overhead power lines are the prevailing facilities to carry electric energy along big distances. Their proper functioning is very important for the current society due our highly electrical-dependent lifestyle. During their working, overhead power lines are under different phenomena, such as short-circuits, high-speed winds, extreme temperature conditions and impacts, which can disturb their operation and even prevent them to accomplish their objective. As a result, many simulation tools are being presented to analyze the evolution in those situations. This paper presents an application of an electrodynamics simulation tool. This application shows a transient evolution for a given overhead power line during an open-close sequence because of a persistent short-circuit, as well as, a long-time study considering current and environmental temperature variations. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • EMF mitigation in the vicinity of a overhead power line

    Page(s): 308 - 312
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1724 KB) |  | HTML iconHTML  

    Recently the interest in a possible relation between electromagnetic fields created by some electric facilities, such as high voltage lines and substations, and health has been increasing. This has motivated many organizations to propose regulations to establish exposure values under electromagnetic fields. This implies the need to evaluate or measure the value of these fields. A way to accomplish this evaluation is by means of software tools. These tools can be developed taking into account different degrees of simplifications, depending on precision requirements. In some cases, the consideration of lines which conductors are perfectly horizontal and infinite can produce unacceptable results. On the other hand, solving exact models, which use Maxwell's Equation, are too complex and provide unnecessary accuracies. This work is focused on showing some simulations of EMF generated by an overhead power line under different conditions and the presence of different passive conductor meshes is analyzed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Multi-electrode arc furnace technology with improved metal processing capability using current driven mixing

    Page(s): 313 - 316
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1424 KB) |  | HTML iconHTML  

    This paper presents a finite element solution for three-dimensional isothermal flow for DC arc furnace where low frequency AC component is added. Electrodes of the furnace are connected with independent supply sources. Current densities, magnetic flux densities, force densities and flow of molten metal are investigated in the case of two different furnace constructions. Methodology for supply source control described in this paper can be used in industrial applications for mixing molten metals or other conductive liquids. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Equivalent substitution method-based failures analysis for electromagnetic loop

    Page(s): 317 - 322
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (929 KB) |  | HTML iconHTML  

    A new electromagnetic loop with Voltage Class of 500kv and 220kv are constantly generated when 500kv power network is being constructed in China. Optimizing for the existing layering partition is of great significance to the safety and stably operation of the grid. The short circuit current calculation is crucial to the selection of grid's equipment and scheme for layering partition between electromagnetic loop ring opening and electromagnetic loop ring. This paper presents a new concept of model for power systems calculations based on the operational curve law. The model takes power system model as points stand for electrical components and lines which stands for logical relationship, and this model is established based on the grid characteristic of electromagnetic loop, it can be used for failure analysis on short circuit in electromagnetic loop. The simulation results show that the model has a high fitness and reliability for electromagnetic loop, though the considerations of transfer impedance are still insufficient, this new model has a very large dominant position from traditional algorithm in calculating short circuit current for electromagnetic loop. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Ex situ CO2 mineralization via nesquehonite: A first attempt for an industrial application

    Page(s): 323 - 327
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (359 KB) |  | HTML iconHTML  

    A novel method to synthesize nesquehonite, MgCO3 · 3H2O, via reaction of a flux of gaseous CO2 with Mg chloride solution at ambient conditions, performed using a reactor, is here described. The reaction rate of the process is rapid, with deposition of abundant carbonate in few minutes. The results of a multi-disciplinary methodology, including SEM-EDAX, XRD, ICP-AES and thermal analysis, suggest that the application of our method at industrial scale can be considered. Moreover, the possibility to involve in the process saline wastewater as source of Mg makes the method a promising complementary solution in the sequestration of anthropogenic CO2 at the expense of saline wastewater. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Enhanced PLL system for Harmonic Analysis through Genetic Algorithm application

    Page(s): 328 - 333
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (986 KB) |  | HTML iconHTML  

    After an introduction to PLL and PLL based systems, an analysis of the methods to improve the performance of such systems aimed to the Harmonic Analysis is presented. Among these methods an approach to using the Genetic Algorithm is shown with its results. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Artificial Bee Colony based optimal management of microgrid

    Page(s): 334 - 339
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (748 KB) |  | HTML iconHTML  

    Due to ever increasing energy demand and expectation, microgrid has received a great attention. Microgrid can be viewed as a cluster of loads and parallel DG units installed at consumer's sites. The main objective of this paper is to address on the issue of optimal operating strategy and cost optimization scheme for a microgrid using three evolutionary techniques, namely Particle Swarm Optimization (PSO), Craziness based Particle Swarm Optimization (CRPSO) and Artificial Bee Colony (ABC) algorithms. In this paper a microgrid with wind turbine, PV array, diesel engine, fuel cell and microturbine are studied. The proposed cost function considered are the cost of the emissions NOx, SO2 and CO2, operating and maintenance cost as well as start- up costs of different sources. The total operating cost of the microgrid is minimized with the help of optimization techniques. It is seen from the results that the ABC based algorithm provides the best economic solution with the minimum use of diesel engine. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An overwiev on IEEE Std 2030

    Page(s): 340 - 345
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1118 KB) |  | HTML iconHTML  

    An overview of the IEEE Standard 2030, IEEE Guide for Smart Grid Interoperability of Energy Technology and Information Technology Operation with the Electric Power System (EPS), End-Use Applications, and Loads, is presented. The article well explains as the interoperability is the first step versus a complete integration of Smart Grids. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Rective power concept extended into time domain

    Page(s): 346 - 351
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (726 KB) |  | HTML iconHTML  

    The requirements for accurate power components computation are raised through power delivery optimization and energy tariffs. The authors propose an orthogonality operator constituting the key tool in power computation for non-sinusoidal signals. The definitions of instantaneous reactive and distortion power have been formulated entirely in time domain. They constitute a natural extension of Budeanu concept. The proposed approach is restricted to time domain and therefore simple and suitable for implementation in smart metering systems. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Preventive actions in protection relays network using SNMP

    Page(s): 36 - 40
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1175 KB) |  | HTML iconHTML  

    Energy automation systems have been expanding and there are more Ethernet capable devices in the network. Protection relays, switches, GPS and also computers have many critic diagnosis information available via the network interface. The intention of this paper is to present how the already available information can be used in the human-machine interfaces and SCADA systems to have a more detailed diagnosis of the network and its devices. Information like IED (Intelligent Electronic Devices) health status, CPU loads, fiber-optics light intensity, GOOSE (Generic Oriented Object Substation Event) message errors, can be used to early detect equipment failure and network instabilities. Early analysis can prevent problems with the equipment interlocking and protection functionalities and improves the power system availability. The simple network management protocol (SNMP) is a management protocol widely implemented, which makes it an ideal manufacturer-independent solution for this purpose. To test this concept a Siemens SCADA system was used as a manager of the SNMP enabled devices in an already commissioned power plant with Siemens Siprotec 4 protection relays. Further ideas were also developed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Development of Electrochemical Impedance Spectroscopy instrument for survey on fuel cell

    Page(s): 352 - 358
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (993 KB) |  | HTML iconHTML  

    After a description of Electrochemical Impedance Spectroscopy methods, a new instrument extremely cheaper than market ones and suitable for fuel cells investigation will be presented. The characteristics for the system will be calculated and presented also together with some measurements realized. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analyzing technical and economical aspects of running emergency demand response programs in smart grids

    Page(s): 359 - 364
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (874 KB) |  | HTML iconHTML  

    This paper explores the impact of smart grid on implementation of emergency demand response programs (EDRPs). In this regard, the power model of EDRP with consideration of incentive rate for customers who respond to reducing their loads is developed. The methodology is demonstrated through case study simulated on Iranian power system. The impact of smart grid on EDRP programs is discussed and it is shown that EDRP programs would be executed more effectively in a smart grid. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel faulted phase selector for double circuit transmission lines by employing adaptive cumulative sum-based method

    Page(s): 365 - 370
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (843 KB) |  | HTML iconHTML  

    In this paper a novel approach is proposed for faulted phase selection in transmission lines. This new approach is based on adaptive cumulative sum method which is proposed by authors. In this method, adaptive cumulative sum-based algorithm (ACUSUM) is applied to each phase current and pre-defined indices are obtained. It is shown that by monitoring these output indices and comparing them with an appropriate threshold, faulted phases can be detected, only 4 ms after fault inception. This new faulted phase selector can be also applied to double circuit transmission lines in order to detect cross-faults as well as inter-circuit faults. The implementation of the proposed method is simple and need no complicated hardware and equipment. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimal DG sizing in primary distribution feeders using dynamic programming approach

    Page(s): 371 - 375
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (917 KB) |  | HTML iconHTML  

    Distributed generation (DG) corresponds to the application of small generating units which are the set up in distribution systems or near load centers. Utilization of DG influences various operational indices of the distribution feeders such as feeder loading, electrical losses and voltage profile. In addition, use of DG in its appropriate size is an essential tool to attain the DG maximum potential advantages. In this paper, an optimization method is proposed to determine the optimal size of DG in the distribution system. This method considers the system technical factors such as losses, voltage profile and loading of the primary distribution system feeders. The optimization process is solved by the forward dynamic programming (DP) algorithm to evaluate the DG effects on the mentioned technical parameters. The proposed method has been applied to the typical section of the distribution system in Iran and the results have been reported. The obtained results prove that the application of DG in its optimal size can cause the considerable improvement in the distribution system efficiency. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Particle Swarm Optimization and hybrid algorithm applied to generation and demand dispatch

    Page(s): 376 - 381
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (729 KB) |  | HTML iconHTML  

    This paper addresses the generation and demand dispatch problem using the Particle Swarm Optimization (PSO) technique and a hybrid algorithm, based on the PSO and the differential evolution algorithm. The problem is formulated in the context of a small grid, whose manager dispatches generation and flexible demand along a time horizon in order to minimize generation costs. Unit commitment of generation units is represented. Power flow equality constraints and inequality constraints due to operational limits are modeled. Two applications, one using the IEEE 30-bus test system, are conducted in order to assess and compare both evolutionary algorithms performance. The importance of comparing stochastic algorithms performance on a statistical base is stated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Energy storage sizing for dispatchability of wind farm

    Page(s): 382 - 387
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (967 KB) |  | HTML iconHTML  

    The undispatchability of wind farm presents lots of integration problems to safe operation of power system. Designing energy storage system for Dispatchability of wind farm is an effective integration solution. This paper presents a novel sizing method of energy storage system for dispatchability of wind farm with different confidence level. The forecast data of wind power is generated base on persistence method, and then based on forecast data a dispatch strategy is proposed for the minimization of energy storage size. For the compromise between dispatchability of wind farm and energy storage size, different confidence level of dispatchability can be defined as constraint and constraint function of energy storage rated power and capacity is established with non-parametric estimation and curve fitting. The investment cost model considering lifetime of energy storage is proposed as objective function with constraint function. For obtaining optimal energy storage size, genetic algorithm is used to solve the non-linear objective function. Finally, the sizing method is illustrated by an example adopting lithium-ion battery energy storage system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Economic load dispatch including wind power using plant growth simulation algorithm

    Page(s): 388 - 393
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (778 KB) |  | HTML iconHTML  

    The economic load dispatch (ELD) to meet the system load demand in an optimal manner is discussed in this paper by considering wind power in power system. The generation scheduling for overall system comprising coal based units and wind farm is derived by solving an objective function using plant growth simulation algorithm (PGSA). Uncertain nature of wind power is included in study by using weibull probability distribution function. The errors in wind forecasting are taken in to account by adding costs such as overestimation cost and under estimation cost. The economic load dispatch problem solved for three test cases considers different constraints like valve point loading effect, ramp rates, power loss and prohibited zones. The results obtained without wind are compared with those presented in previous literature to validate feasibility of PGSA. It is shown that PGSA provides better results for fuel cost compared to Genetic Algorithm (GA), Particle Swarm Optimization (PSO), Biogeography-based optimization (BBO) and Variable Scaling Hybrid Differential Evolution (VSHDE). View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Simple broadband anti-reflective coatings for superstrate-type silicon-based tandem cells

    Page(s): 394 - 396
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (727 KB) |  | HTML iconHTML  

    In this paper, the superstrate-type silicon-based tandem cells between air and glass are added to a porous SiO2/MgF2 double-layer anti-reflective (DLAR) thin film structure in order to improve the glass substrate low reflectivity in a wide spectral range (400-1200 nm), without high reflectivity in the near-infrared region. Practical discussion is presented, as well as experimental results of fabricated films and devices. Application of the experimental porous SiO2/MgF2 DLAR thin film to conventional silicon-based tandem solar cells results in improvement of the short-circuit current density by 6.82%. Solar cell efficiency is improved by 7.14%. The presented experimental porous SiO2/MgF2 DLAR thin film structure provides anti-reflective results in a broad range of visible light, without high reflectivity at near-infrared wavelengths. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Modified teaching learning based algorithm for economic load dispatch incorporating wind power

    Page(s): 397 - 402
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (764 KB) |  | HTML iconHTML  

    An economic load dispatch problem (ELD) for power system consisting of thermal generators integrated with wind farm is solved. Wind speed which is essentially a random variable is characterized by weibull probability density function (pdf). Apart from classic economic dispatch term in an objective function, the terms such as direct cost, overestimation and underestimation of available wind power are included. The simulation results for three tests systems are presented using Modified Teaching Learning Based optimization algorithm (MTLBO). To validate the efficacy of proposed method an ELD problem is solved without considering wind power penetration and the results obtained by MTLBO are compared with other algorithms such as Genetic Algorithm (GA), particle swarm optimization (PSO), biogeography-based optimization (BBO) and variable scaling hybrid differential evolution (VSHDE). The minimum cost of electricity obtained by MTLBO algorithm is shown to be better than or comparable to these methods. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel measurement technique for extra high voltage bus bar fault detection

    Page(s): 403 - 406
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (726 KB) |  | HTML iconHTML  

    This paper introduces a new fault detection tool for Extra High Voltage (EHV) busbars. The new tool is to be used by extra high speed digital relays to detect busbar faults besides differentiating between close up line faults and busbar ones. The suggested tool uses a new technique that squares both of the instantaneous voltage signal and its complement to produce a unity relation in normal operating conditions. The unity relation will remain undistorted as long as the power system is operating normally; however, this unity relation will change with any sudden change in the voltage signals due to any abnormal conditions. The new tool is then applied on the travelling wave equations to discriminate busbar faults from line ones. The suggested tool is being applied to a 500 kV. busbar arrangement chosen from the Egyptian unified network. The simulation results indicate the capability of the new tool for the detection and discrimination of all types of busbar faults. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.