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Issue 1, Volume 5,
January 2010
Title of the Paper: 3D Finite Element
Analysis for Arcing Chamber Optimization of the Current-limiting Circuit
Breaker
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Authors: Elena Otilia
Virjoghe, Diana Enescu, Marcel Ionel, Florin Mihail Stan
Abstract: Direct current, which was one of the main means of distributing
electric power, is still widespread today in the electrical plants supplying
particular industrial applications. The advantages in terms of settings,
offered by the applicants of d.c. motors and by supply through a single line,
make direct current supply a good solution for railway and underground
systems, trams, lifts and other transport means. The paper presents the
calculation of the magnetic field in the arcing chamber of the
current-limiting circuit breaker of the direct current 1250 A, 750 V.
Current-limiting circuit breakers play an important role in electrical
low-voltage circuits. Due to the high short-circuit currents it is necessary a
very short time to switch off the defective branch. For this the current
limiting circuit breakers are conceived as elaborated solutions especially for
the arc quenching system, meaning the path of current and the arcing chamber.
In this paper the authors present few optimization solutions of some quenching
systems which will lead to more performing constructive choices. The finite
element software package ANSYS is use for calculation of the magnetic field
components.
Keywords: Arcing chamber,
magnetic field, current-limiting circuit breaker, finite element method,
software package ANSYS, optimization, numerical simulation
Title of the Paper: Estonian
Electricity Production Scenarios and their CO2 and SO2 Emissions until 2030
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Authors: R.
Kuhi-Thalfeldt, A. Kuhi-Thalfeldt, J. Valtin
Abstract: Closing of old oil-shale based power plants and fast development of
wind power has raised several issues regarding possible future electricity
production capacities in Estonia and their environmental performance. In
February 2009 Estonian government adopted a new Development Plan of Energy
Sector until 2020. This study was performed in conjunction to the strategic
environmental assessment of the plan highlighting especially the CO2 and SO2
emissions of electricity production scenarios. The analysis is carried out
using the Long range Energy Alternatives Planning System (LEAP) software,
which is suitable for elaborating the scenarios and their impact on power
balance and to the environment.
Keywords: Estonia,
development plan, CO2 emissions, SO2 emissions, oil shale, wind power
Title of the Paper: Sensitivity of
Compact Fluorescent Lamps during Voltage Sags: An Experimental Investigation
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Authors: Hussain Shareef,
Azah Mohamed, Khodijah Mohamed
Abstract: The aim of this paper is to analyze the sensitivity of various
compact fluorescent lamps (CFLs) which are used in residential and commercial
applications during voltage sags. Laboratory tests were performed on different
CFLs commonly available in the market. The tests are based on recent testing
standards and utilizing a modern industrial power corruptor. For predefined
malfunction criterion of zero illuminance condition, sag depth and duration
are varied to construct individual voltage immunity curves. Experimental
results show that all CFLs are sensitive to voltage sags and vary in a wide
range. It also proves that some brands of CFLs having similar power rating are
sensitive to both sag magnitudes and its duration. Finally a method to improve
the sensitivity of CFLs to voltage sags is implemented. This technique
increases the holdup time of the dc bus voltage by connecting additional dc
capacitance at the rectifier output of the CFL’s ballast circuit.
Keywords: Voltage sag,
ride through capability, ballast, CFL, voltage tolerance curves
Title of the Paper: Electromagnetic
Force Analyzed Results on Switchgear of Disconnector for Overevoltage
Protector
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Authors: Hitoshi Kijima,
Tomooki Hasegawa
Abstract: A disconnector for overvoltage protector (OVP) is equipment which
intercepts a circuit safely, when OVP breaks down in short circuit mode. As a
disconnector, a Circuit Breaker (CB) is normally used. When a large current
such as a lightning surge flows, switchgear of CB comes floating according to
the electromagnetic force generated by large current which flows into a
switchgear. The function of OVP is spoiled by this influence. If the problem
which the switchgear comes floating can be solved, even when a large lightning
surge flows through it, electrical aparatus can be protected by OVP.We have
been analyzing this switchgear floating mechanisms using finit element method.
This paper presents a way of preventing switchgear floating.
Keywords: Circuit breaker,
lightning surge current, switch floating, current density, electromagnetic
force
Issue 2, Volume 5,
April 2010
Title of the Paper: Preventing
Over-offering Behavior in Capacity Markets
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Authors: X. Wei, R. Li
Abstract: Capacity markets provides additional revenue stream for the power
suppliers. In a capacity-energy combined market environment, suppliers have
incentives to deliberately over-offering their capacities in the capacity
market while bid very high price in the energy and ancillary markets to avoid
operation. This paper analyzes the risks and profits of this
capacity-over-offering behavior, and develops a method for computing
non-operable penalty level which can prevent the capacity-over-offering
behavior. It is found that the effective penalty level is highly correlated
with the stochastic characteristics of supplier’s profit streams and
supplier’s risk attitudes. Two types of suppliers are suggested as the
potential cheaters in the analysis. The methodology and the results are
potentially useful for the operation and mitigation in a capacity-energy
market environment.
Keywords: Capacity Market,
Over-offering, Risk Analysis, Non-operable Penalty, Prospect Theory,
Monte-Carlo Simulation
Title of the Paper: An Efficient
Maximum Power Point Tracking Controller for Photovoltaic Systems Using New
Boost Converter Design and Improved Control Algorithm
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Authors: Tamer T. N.
Khatib, A. Mohamed, N. Amin, K. Sopian
Abstract: This paper presents an efficient maximum power point tracking (MPPT)
controller for a standalone photovoltaic (PV) generation system. To achieve an
efficient MPPT controller, a new boost converter design and an improved MPPT
algorithm are incorporated. In the proposed boost converter design, a passive
regenerative snubber circuit is included to absorb the energy of stray
inductance so as to reduce the IGBT switching losses. As for the improved MPPT
algorithm, it is based on the curve fitting method which attempts to predict
the power-voltage characteristic curve by a fourth order polynomial function.
The predicted P-V curve strongly depends on the cell temperature and therefore
the ambient temperature and solar radiation are used to track the maximum
power point (MPP) of the PV module. Experimental results are given to verify
the validity and performance of the MPPT algorithm which is embedded in a
prototype MPPT controller. The experimental results showed that the proposed
MPPT controller successfully tracked the MPP by giving an average tracking
efficiency of 89.2%.
Keywords: MPPT,
photovoltaic systems, PV controller, boost converter, curve fitting
Title of the Paper: Numerical
Simulation of Single Phase Faults in Medium Voltage Electrical Networks
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Authors: Dumitru Toader,
Stefan Haragus, Constantin Blaj, Iulia Cata
Abstract: In the paper is presented a virtual simulator for three-phased
medium voltage electric circuits. The simulator allows analyzing transient
regimes caused by the faults produced in electric distribution networks
(simple grounding, double grounding, broken and grounded conductor). Also, in
paper are presented the results of measurements made in the experimental area
that was conceived for verification results obtained by numerical simulation
in real condition. There are analyzed the dependence of the transient regimes
on the initial phase of the voltage at the faulty place, the dependence on the
grounding resistance at the faulty place and on the method used for grounding
the neutral point of the electric network.
Keywords: Medium voltage
electric networks, grounding faults, numerical simulation
Title of the Paper: Experimental
Characterization and Modeling of PEM Fuel Cells under Dynamic Load Variations
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Authors: Giovanni Bucci,
Edoardo Fiorucci, Fabrizio Ciancetta, Francesco Veglio
Abstract:The adoption of fuel cells (FCs) for industrial applications,
transportations and home power generation is widely increased during recent
years. Because FCs are still in the development stage, to evaluate and
validate fuel cell technologies suitable test systems are needed. In a fuel
cell both chemical and electric sections can be founded, so to control its
behaviour the measurement of different parameters, as current, voltage, flow
rate of the reactants and cell temperature is required. The performance
evaluation of a fuel cell requires both static and dynamic characterizations,
especially for the automotive applications, in which there is a dynamic
variation of electric load. To better design this kind of applications, a FC
mathematical model is required, to evaluate the performance at different
working conditions. The synthesis of a dynamic model describing the FC
behavior should be performed starting form the real system configuration,
including pipes, flow and pressure regulators and valves. To this aim an
automatic measurement system for the characterization of PEM (Polymer
Electrolyte Membrane) fuel cells has been developed, and in this paper a
dynamic model of a fuel cells stack is proposed, which has been validated
through experimental measures.
Keywords: Fuel cells, Test
system, Characterization, Data acquisition system, Dynamic testing,
Supercapacitor
Title of the Paper: Performance
Analysis and Comparative Study of LMI-Based Iterative PID Load-Frequency
Controllers of a Single-Area Power System
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Authors: Ahmed
Bensenouci, A. M. Abdel Ghany
Abstract: This paper provides a comparison of the performance and the design
steps for four robust static output feedback Proportional-Integral-Derivative
(PID) controllers. The first one presents an Iterative PID (IPID) that
guarantees the stability of the closed-loop system. In the second and the
third controllers, Iterative PID based on H2 (IPIDH2) and H? (IPIDHI)
performances, respectively, are investigated. The role of H? is to minimize
the disturbance effect whereas H2 is used to improve the transients of the
system output. The last one is an Iterative PID that is characterized by the
Maximum (IPIDM) regulated output of the closed loop system with its command
input being bounded. The Iterative Linear Matrix Inequality (ILMI) technique
is developed to find the feedback gains of the designed PID controllers. The
proposed design technique is applied to the Load Frequency Control (LFC)
problem of a single-area power system. The effects of ILMI tuning variables on
the system dynamic response are given and discussed. To test and compare the
effectiveness of the controllers, diverse simulation tests are carried out
under diverse disturbances and parameters change with the presence of the
Generation Rate Constraint (GRC), inherent system nonlinearity. The results
prove that the proposed iterative PID controllers are very useful for LFC
power system.
Keywords: Load frequency
control, Iterative PID, Linear matrix inequalities, H-infinity norm, H-2 norm,
maximum power output control
Title of the Paper: Applicability of
Trigeneration Systems in the Hotel Buildings: The North Cyprus Case
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Authors: M. Ozdenefe, U.
Atikol
Abstract: In North Cyprus (N. Cyprus), the installed power capacity fails to
meet the demand in severe winter and summer conditions thus; new power
capacities are needed to supply the required demand. One way of dealing with
the deficiencies resulting from the inadequacy of installed power capacity is
to make the distributed power widespread, especially the trigeneration systems
which exploit energy in the fuel in the most efficient way by producing heat,
electricity and cooling simultaneously. The objective of the present work is
to propose a methodology through which the decision makers can assess the
applicability of trigeneration systems for the hotel sector. The power demand
of a representative hotel in N. Cyprus was monitored and segregated into base
and cooling components for typical days of summer. On the other hand, five
hotels were selected for conducting surveys on their electricity and heat
demands. Correlations were obtained for the representative hotel for two
different scenarios of capacity sizing; in scenario 1, it was aimed to meet
the maximum value of the base electrical load of the hotels and in scenario 2
the aim was to meet the minimum base electrical load. The experimental
correlations were used in determining the capacities of the trigeneration
systems for the other five hotels. An economical feasibility analysis is
carried out for both scenarios. The results showed that the application of
trigeneration systems to the hotel sector in N. Cyprus can be feasible. It is
found that application of scenario 2 is more feasible than application of
scenario 1. For the representative hotel the simple payback period and savings
to investment ratio of the trigeneration application based on scenario 2 is
found to be 3.3 years and 1.8 respectively, which are acceptable. Other hotels
investigated in this work also have similar results when the scenario 2 is
applied. In addition to this, it is found that further benefit is achieved if
the excess electricity is sold to the utility. By the application of scenario
2 to the hotels considered in this work; total annual electricity production
by the systems would be 16.7 GWh. Considering the electricity production by
the utility via gas turbines was 4 GWh in the year 2007, the application of
the trigeneration systems would not only erase the running and maintenance
costs of these old and inefficient units but also reduce the load coming to
the power plants.
Keywords: Trigeneration,
absorption chiller, economical analysis, energy, power demand, hotels
Title of the Paper: Optimal Allocation
of FACTS Devices in Deregulated Electricity Market Using Bees Algorithm
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Authors: R. Mohamad
Idris, A. Khairuddin, M. W. Mustafa
Abstract: In this paper, a novel method using Bees Algorithm is proposed to
determine the optimal allocation of FACTS devices for maximizing the Available
Transfer Capability (ATC) of power transactions between source and sink areas
in the deregulated power system. The optimizations are made on three
parameters: the location of the devices, their types and their sizes. The
FACTS devices are located in order to enhance the available transfer
capability (ATC) between source and sink area. Four types of emerging FACTS
controllers are used and modeled for steady state studies, namely; TCSC, SVC,
UPFC and TCPST. The IEEE9 bus test system and IEEE118 Bus test system are used
to illustrate the applicability of the proposed algorithm to enhance ATC
effectively. The installation costs of FACTS devices are also included. A
Genetic Algorithm (GA) configured to the same purpose is used for validation.
Results show the difference of efficiency of the devices used in this
situation. They also show that simultaneous use of several kinds of
controllers is the most efficient solution to increase the ATC. The obtained
results indicate that both techniques can successfully find the optimal
solution and parameter setting of FACTS devices, but BA is better in term of
value of objective function and speed of convergence compared to GA.
Keywords: Bees Algorithm,
GA, ATC, FACTS, SVC, UPFC, TCPST, TCSC
Title of the Paper: Optimal
Configuration of a Renewable-based Electricity Supply Sector
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Authors: Tino
Aboumahboub, Katrin Schaber, Peter Tzscheutschler, Thomas Hamacher
Abstract: Proposed emission reduction targets as well as the scarcity of
fossil fuel resources make a transition of the energy system towards a carbon
free electricity supply necessary. Promising energy resources are solar and
wind energy. The high temporal and geographical variability of these resources
is challenging for their integration. This study focuses on the question how a
renewable-based energy system ideally should be designed. We investigate the
optimal structure of a prospective renewable-based power supply system on two
different scales: on the global and the European level. The paper describes
the applied simulation technique, based on linear optimization, employed to
combine an adequately precise geographical coverage with high temporal
resolution. As results we obtain ideal energy mixes, generation sites, storage
and interregional power transmission capacities required for different
scenarios of highly renewable supply.
Keywords: Renewable
Energy, Simulation, Linear Optimization, Power Supply, Geographic Information
System (GIS), Supergrid, Energy System Model
Title of the Paper: Study for the
Integrated Automation of the Sao Paulo Subway System Rectifier Substations
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Authors: Eduardo Mario
Dias, Sergio Luiz Pereira, Carlos Alberto De Sousa
Abstract: This article shows a proposal for the integrated automation of the
Sao Paulo subway system rectifier substations, supported on the gains of
reliability which may be obtained in case it is implemented, and in the
improvement of the efficiency of operation of the system open to question. To
quantify these profits of reliability there is presented the development of
the model of reliability of Markov devoted to the system of automation of
rectifying substations. The used methodology proceeded to the lifting and
analysis of the incidents when they were opened in the years of 2006, 2007 and
2008 in the rectifier substations of the subway of Sao Paulo, calculating HIS
MTBF (Mean Time Between Failures). The study ends that the profit of
reliability is significant in what it refers to the improvement of public
transport with the application of the integration of the automation of the
rectifying substations.
Keywords: Automation,
Integrated automation system; rectifier substation; rectifier protection
system
Title of the Paper: The Slovenian
Electricity Market and the Prices of Electricity
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Authors: Viljem Pozeb,
Tina Krope, Darko Goricanec, Jurij Krope
Abstract: The article is based on the analysis of the circumstances, occurred
after the electricity market opening in the Republic of Slovenia, as a
consequence of implementation of the EU legislation in the energy field. The
market operation, the role of the national regulatory authority and the market
conditions are described, all of which influences the supply and prices of
electricity in 2010. Additionally, a model of price formation for industrial
and household consumers is presented and an overview of the production and end
use of electrical power in Slovenia.
Keywords: Energy,
Electricity Market, Preferential Producers, Regulatory Authority, the
Structure of the Electricity Price
Issue 3, Volume 5,
July 2010
Title of the Paper: The Development of
Electricity Market in the European Union and the Legislative Framework
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Authors: Tina Krope,
Viljem Pozeb, Darko Goricanec
Abstract: The article gives an overview of the legislative framework at the EU
level, describes the market operation, pointing out possible measures and
activities, needed for the creation of a fully liberalised electricity market.
Physical flow of electricity through the supply chain, from generation,
transformation, distribution and supply to customers is described. Mechanisms
to support preferential electricity production from some promising energy
transformation technologies and possible solutions applicable for ensuring the
use of renewable energy sources for production of electricity are discussed.
Keywords: EU - Energy
market, Electricity market, Legislation, Renewable energy sources, Production
of electricity
Title of the Paper: Interpersonal
Dependency on People with Major Depression Syndrome in Indonesia
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Authors: Dery
Abdurrachim Iskandar
Abstract: From cognitive model approach perspective, a person with major
depressive disorder has commonly five depression symptoms i.e. affective,
cognitive, motivational, physical and behavioral symptoms. Cognitive model
expresses high possible dependency on a person with depression syndrome as one
real form of behavioral symptom. High possibility on one person with
depressive disorder tends to give him/her high possibility for interpersonal
dependency, one dependency one experienced by a person making another person
the dependent object. Used research method is qualitative with interview
approach equipped with observation method. The population includes people who
have been diagnosed for mayor depression by both psychologists and
psychiatrist. Sampling has been made using theory based/operation construct in
which the sample is selected by certain criteria, based on theory or
operational depression construct included into DSM IV TR. here are various
interpersonal dependencies on some people with depressive disorder classified
into four dimensions, cognitive, motivational, affective and behavioral
whereas cognitive and affective dimension have more dominant roles. In
addition, there is one extrinsic factor on person with mayor depressive
disorder which has role in the process of interpersonal dependency emergence.
The factor is parenting style.
Keywords: Interpersonal
Dependency, Major Depression, Symptom, Cognitive Models
Title of the Paper: Restoration of
Power System after Blackout and Synchro-Check Relays Setting in Transmission
System
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Authors: Zaneta
Eleschova, Anton Belan, Marek Pipa, Attila Kment
Abstract: Connection of power lines in transmission system is activated after
defined conditions are met in the setting of synchro-check relays; namely ΔV –
difference in voltage amplitudes, Δf – frequency difference, and Δα –
difference in phase angles. The aim of this contribution was experimental
verification of the connection condition focused on transient phenomena course
on connected line, the transient stability of generators, and the analysis of
their influence on power system. As the past critical situations (state of an
imminent blackout threat) in transmission system has shown, inability to
connect line into the power system because the connection conditions are not
met (blocking of a power switch) could have severe negative influence on the
continual operation of the power network. Setting of synchro-check relays as
connection conditions can influence also the process of electric power system
restoration after collapse. Thus, this paper discusses also the actual state
of synchro-check relays setting in transmission system.
Keywords: Transmission
system, Connection of power line, Voltage phase shifts, Synchro-check relay
Title of the Paper: Assessment and
Classification of Line Overload Risk in Power Systems Considering Different
Types of Severity Functions
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Authors: Marayati
Marsadek, Azah Mohamed, Zulkifi Mohd. Norpiah
Abstract: Power system security assessment based on the concept of risk is
required in the current power environment. In risk based security assessment,
the likelihood and severity of security violation are the two main factors
that determine the security level of a power system. To evaluate likelihood of
security violation, the probability technique based on Poisson probability
distribution function is adopted. Severity function signifies the extent of
security violation. Two types of severity functions, namely the continuous and
percentage of violation severity functions are considered in this study. This
paper presents the assessment of risk of line overload at various loading
condition using a risk index. A risk classification technique is also proposed
so as to provide a qualitative interpretation of the risk index value by
classifying the risk as low, medium and high degree of risk. This paper
presents the implementation of line overload security assessment on the IEEE
24 bus test system and practical interconnection power system so as to
investigate the effect of severity functions on risk classification in risk
assessment. Results are presented in terms of risk index curves.
Keywords: Line overload,
Probability, Risk, Severity, Security, Uncertainty
Title of the Paper: Description of
Power System QV Curve by Fuzzy Modeling
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Authors: Shu-Chen Wang,
Chi-Jui Wu
Abstract: The purpose of this paper is to study the description of power
system QV curves by using the method of fuzzy modeling for analysis of voltage
stability. Voltage instability of power system comes from increasing load
rapidly, and causes bus voltage to drop. When voltage is out of control and it
can be voltage collapse. The QV curve can identify voltage stability limit,
and it determine robustness of power system. The method of fuzzy modeling has
been proven to be well-suited for modeling nonlinear industrial processes
described by input-output data. The fuzzy system model is basically a
collection of fuzzy IF-THEN rules that are combined via fuzzy reasoning for
describing the features of a system under study. In view of the nonlinear
characteristic of power system QV curve, the method of fuzzy modeling is
employed for representing the curve. Based on the Sugeno-type fuzzy model,
various models with different numbers of modeling rules are used to describing
the QV curve. It is found that such fuzzy model offers both quantitative and
qualitative descriptions for the QV curve.
Keywords: Fuzzy Modeling,
Sugeno-type, ANFIS, QV Curve, Voltage Stability, Voltage Collapse
Title of the Paper: New Features
Regarding Pumps Command by Electrical Drives
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Authors:
Marius-Constantin Popescu, Nikos E. Mastorakis, Ilie Borcosi, Jean-Octavian
Popescu
Abstract: As compared to hydraulic, pneumatic, or thermal motor devices,
electrical drives have certain advantages owed to the ease of generating,
transporting and distributing the electrical energy. This fact made them
become the first choice in most of the cases emerging in actual activity. The
present paper simulates the behavior of electrical drives powered by
continuous current motors. The efficiency optimizing of the drive systems in
industrial and modern appliances can be done through using vector control with
DSP and intelligent power module for asynchronous motors. The authors
contribution to this paper refer to the proposal and development of a control
system of a rotation AC motor with field oriented control based on the signal
processor TMS320F2812 DSP.
Keywords: Drive system,
Vector control, DSP, Intelligent power module, Nonlinear command
Title of the Paper: Techno-Economic
Analysis of Illegal Electricity Usage in Turkey and Policy Proposals
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Authors: Nevzat Onat
Abstract: Some part of the energy produced in electric power systems does not
reach to consumers who make payment because of output loss and administrative
applications. The energy loss can be considered in two categories as technical
losses and nontechnical losses. Total of these losses is a significant
parameter that affects capacity of the system. In this study, the transmission
and distribution losses in Turkey power system were researched. The studies
carried out for purpose of determining its illegal use and its
socio-economical effects were analyzed. It is impossible to prevent the losses
completely in the electric energy system. However, in developed countries, it
generally remains below 6%. The lost illegal use rate in Turkey was determined
as 14.4%. The cost resulting from only illegal use reaches to values that urge
the economy of Turkey with a rate that is 1.7 times of the annual transmission
and distribution system investment of the country. In terms of energy pricing
Turkey is very competitive situation with European Union and OECD countries.
However, the losses of Turkey are well above the world and OECD averages. To
decrease the technical losses, very serious additional energy investment is
needed in the country. Illegal use rate can be decreased to acceptable rates
as a result of policy changes and some measures. In the study, some solution
suggestions are made to decrease the loss rate that occurs as a result of
illegal use. To achieve decrease in illegal use, some measures can be taken
such as, speeding up privatization policies, regional price policies, raising
of the awareness of the public about economical and social dimensions of the
illegal electric use, encouraging of the public to use other energy sources
means by being informed and supported economically, awarding of the government
officials who determine the illegal use, giving of various incentives to
citizens who denounce such use.
Keywords: Electricity
theft, T&D loses, energy generation, electrical energy demand, cost
Title of the Paper: Analysis of
Turkey's Electric Power Demand Forecast and Generation Models Scenarios for
the Next Ten Years
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Authors: Haydar Bayar,
Nevzat Onat
Abstract: The Turkish Government makes great efforts to increase the new and
renewable energy resources, use new systems with low carbon emission instead
of high carbon emission technologies, make energy saving and decrease the
emission of Carbon-dioxide (CO2) and other sera gases by increasing the energy
productivity by means of preventing losses in energy distribution systems. In
production of electric energy, the high rate of the imported fossil fuel is a
significant advantage. With this regard, the investments made to local and
especially renewable energy resources must be increased. In this study, the
technical and economical parameters such as primary energy resources, demand
increases and price fluctuations are examined in detail. In the study legal
regulations made for that purpose are also considered. By using the data
published by Turkish Electricity Transmission Company (TEIAS), analysis of
important parameters such as energy demand increase rates, investment plans,
change in emission rates expected to occur until year of 2020 according to two
scenarios, in terms of sustainability in energy production, is made.
Consequently, within following ten years, a very small development in energy
investment policies of Turkey is expected with effect of legal arrangements in
favor of renewable energy resources. However, this increase is very low
according to the potential usable in the country. This situation decreases the
competition power of country with the OECD countries in terms of energy
prices. For a sustainable development, the country must make significant
changes in the foreign-dependent energy production policies. In the policies
to be determined, supplying of continuously increasing demand from local
resources must be encouraged. In some regions of the country, measures to
decrease the air pollution that causes important social reactions and health
problems must be taken and by rapidly completing the privatization studies,
the weight of private sector also on installation of new plants must be
increased.
Keywords: Turkey,
sustainable consumption, legal arrangements, energy price, wind, solar,
geothermal energy resources, investment plan, greenhouse gases
Title of the Paper: The AHP and ANP
Models for Transport Environmental Impacts Assessment
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Authors: Helena Brozova,
Miroslav Ruzicka
Abstract: This paper presents an assessment of environmental impact
preferences of transport using the Analytical Hierarchical Process (AHP) and
the Analytical Network Process (ANP). The authors suggest using these methods
within the decision-making process and assessment of transport strategies or
projects and their impacts on the environment. There are many various
dependencies and links among factors influencing the decision-making process
of transport implementation. It is not just environmental impacts that
influences acceptance of decision-making, but also other major factors such as
time (term), space (territory radius) and means of transport (mode). Finally
many expectations of benefits obtained from transport implementation must be
included in the decision-making process as well. The paper shows the
complicated structure of these processes. The AHP model is used for preference
evaluation of environmental impacts without any of the other factors or
characteristics of transport projects, plans or strategies. The ANP model is
more complex and is used for the evaluation including other characteristics of
transports projects. The results of both models are compared.
Keywords: Transport
policies, transport strategies and projects, decision making, environmental
indicators, ANP method
Title of the Paper: Failure Analysis in
Power System by the Discrete Wavelet Transform
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Authors: Ismail
Yilmazlar, Gulden Kokturk
Abstract: Voltage variations are the most common power quality events that may
result in corruption of different industrial processes. The electric power
utility industry requires significant improvement in the quality of power
provided to customers during faults or wide area system disturbance. Power
system failure signals are monitored by using embedded systems. This paper
presents an approach to provide the detection and location in time as well as
the identification of power quality problems which are represented in both
transient and fixed signals. The method was applied by using the discrete
wavelet transform (DWT). The given signal is decomposed with wavelet transform
and any change on the lower frequencies of the signal is detected at the finer
wavelet transform resolution levels. The entropy contents of the signal are
considered and a relationship between this entropy contents and the one of the
corresponding component is accomplished. This paper shows wavelet transform
can be used to reduce data set while covering original information. Because of
the reduced data set embedded systems can work within a wider time range.
Paper helps power system analysis and classifies power system failures.
Keywords: Discrete wavelet
transform, wavelet entropy, power system failure
Title of the Paper: Fuzzy Based SVC
with Coordinated POD for Damping of Oscillations of Power System
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Authors: S. V.
Chandrakar, J. B. Helonde, R. M. Mohril, V. K. Chandrakar
Abstract: This paper is aim to present the SVC intelligent control strategy to
achieve improvement in damping of oscillations of two machine system. The most
of SVC controllers are proportional integral (PI) type, however its
performance under varying system conditions is not satisfactory. This paper
compared the performance of SVC with PI type and fuzzy based control schemes
under various system conditions. The details of intelligent fuzzy control of
SVC have been design to achieve smooth reactive power control. The input
signal for fuzzy logic controller is deviation in measured voltage at SVC
location. The minimum fuzzy rules are applied to achieve maximum performance
of the controller. The additional power oscillation damping (POD) signal is
applied with fuzzy controller to suppress the local mode as well as inter area
mode of oscillations. The proposed fuzzy controller coordination with POD
provides significant improvement in damping of the system. The effectiveness
of the proposed control strategy is demonstrated in two machine systems. The
results are validated in MATLAB.
Keywords: SVC, Fuzzy logic
control, damping of oscillations, power system
Title of the Paper: A Reliable Fuzzy
Logic approach for Measurement Data Validation through Line Susceptance
Estimation
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Authors: K. N.
Bhanuprakash, A. D. Kulkarni, B. R. Lakshmikantha, T. Ananthapadmanabha, K.
Balaraman
Abstract: A novel approach is described to estimate the transmission line
susceptances using the linear power flow model with linear relation between
the measurement vector and the susceptance vector. The presently estimated
susceptance is compared with the already stored correct value, to determine
validity of the present measurement using the fuzzy inference.
Keywords: Data Validation,
lower and upper bounds of state estimation, Interval arithmetic, Fuzzy logic,
Reliabality
Issue 4, Volume 5,
October 2010
Title of the Paper: Five Level Parallel
Inverter for DTC – SVM of Induction Motor
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Authors: Jagan Mohana
Rao Malla, Siva Ganesh Malla
Abstract: Direct Torque Control is a control technique used in AC drive
systems to obtain high performance torque control. The conventional DTC drive
contains a pair of hysteresis comparators, a flux and torque estimator and a
voltage vector selection table. The torque and flux are controlled
simultaneously by applying suitable voltage vectors, and by limiting these
quantities within their hysteresis bands, de-coupled control of torque and
flux can be achieved. However, as with other hysteresis-bases systems, DTC
drives utilizing hysteresis comparators suffer from high torque ripple and
variable switching frequency. The most common solution to this problem is to
use the space vector with multilevel inverter depends on the reference torque
and flux. The reference voltage vector is then realized using a voltage vector
modulator. Several variations of DTC-SVM with low cost multilevel inverter or
parallel inverter (five level) have been proposed and discussed in the
literature. The work of this project is to study, evaluate and compare the
various techniques of the DTC-SVM with parallel inverter applied to the
induction machines through simulations. The simulations were carried out using
MATLAB/SIMULINK simulation package. Evaluation was made based on the drive
performance, which includes dynamic torque and flux responses, feasibility and
the complexity of the systems. It is better technology in electric vehicles.
Keywords: Multilevel
inverter, DTC-SVM, Converter, Electric Vehicles, Reliability, SVPWM, 5 Level
parallel Inverter
Title of the Paper: Dynamic Analysis of
Grid Connected Wind Turbine with a Permanent Magnet Synchronous Generator
during Fault Conditions
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Authors: Lata Gidwani,
Harpal Tiwari
Abstract: The use of wind turbines is increasing at very high rates in many
countries around the world. Studies to evaluate the impact of connecting these
new generation units to the existing power systems must be done. This paper
proposes a wind energy conversion system for a grid connected permanent magnet
synchronous generator (PMSG) and power electronic converter system. The model
includes a PMSG model, a pitch-angled controlled wind turbine model, power
electronic converters and a power system model. The control schemes in the
paper include a pitch angle control for the wind turbine and voltage, var and
current control for the power electronic converter. A phase to phase fault is
simulated on 132 KV bus of power system model and the measured results
obtained from grid connection of the permanent magnet synchronous generator
are presented followed by some conclusions.
Keywords: Permanent
Magnet, Synchronous Generator, Power Grid, Power Electronic Converter, Fault
Title of the Paper: Innovative
Technologies for Romanian Anti-Hail System
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Authors: Laurentiu
Alboteanu, Constantin Sulea, Gheorghe Manolea
Abstract: About 60% storms on the Romanian territory (during the
march-September period of one year) are accompanied by hail falls and 40% of
these hail falls lead to significant or even total losses of crops. So, this
is a new and actual research domain that the present work is related to and
its main goal consists in building up a study concerning the existing
technical solutions and exploring some new ways in order to solve the
identified problems. The paper outlines the concerns of the research team at
the University of Craiova, Innovation and Technology Transfer Centre - CITT on
combating hail. Mainly, the researches concern the equipments and the
innovative technologies for Romanian anti-hail systems.
Keywords: Anti-hail,
microcontroller, photovoltaic system, informatic system, monitoring
information, environment
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