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Issue 1, Volume 6,
January 2011
Title of the Paper: IDCGA Based
Evaluation of Network Losses Role in TNEP under Uncertainty in Demand
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Authors: H. Hosseini, S.
Jalilzadeh, A. Kimiyaghalam, A. Bagheri
Abstract: Transmission network expansion planning (TNEP) is an important
component of power system planning. It determines the characteristic and
performance of the future electric power network and influences the power
system operation directly. Up till now, various methods have been presented
for the solution of static TNEP (STNEP) problem. However, in all of them,
STNEP problem has been solved regardless of the network losses role in TNEP
under uncertainty in demand. Thus, in this paper, the role of network losses
in STNEP problem is being studied under uncertainty in demand using an
improved decimal codification genetic algorithm (IDCGA). The effectiveness of
the proposed idea is tested on an actual transmission network of the
Azerbaijan regional electric company, Iran. The results reveal that,
considering the losses even for transmission expansion planning of a multi
voltage level network with low load growth is caused that operational costs
decreases considerably and the network satisfies the requirement of delivering
electric power more safely and reliable to load centers.
Keywords: Transmission
expansion planning, Uncertainty in demand, Network losses, IDCGA
Title of the Paper: Identifying Factors
of Energy Usage in Taiwan
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Authors: Jui-Chen Yu,
Hung-Jen Yang, Lung-Hsing Kuo, Hsieh-Hua Yang
Abstract: The purpose of this study was to identify the energy use in Taiwan.
Logit regression analyses on a large micro-dataset reveal how energy use
characteristics can help explain the energy. Using CR5.0 regression models,
this paper explored the factors affecting energy demand conditional on energy
forms, sectors and sources. Results suggest that explained models could be
used as a well foundation for energy policy decision making.
Keywords: Factor, Energy
Use, Energy Indicators, Model
Title of the Paper: Robust Controller
for Interleaved DC-DC Converters and Buck Inverter in Grid-Connected
Photovoltaic Systems
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Authors: Hassan
Abouobaida, Mohamed Cherkaoui
Abstract: The present work describes the analysis, modeling and control of an
interleaved Boost converters and Buck power inverter used as a DC-DC and DC-AC
power conditioning stage for grid-connected photovoltaic (PV) systems. To
maximize the steady-state input-output energy transfer ratio a backstepping
controller is designed to assure output unity power factor and a Maximum Power
Point Tracking (MPPT) algorithm to optimize the PV energy extraction. The
achievement of the DC-AC conversion at unity power factor and the efficient
PV’s energy extraction are validated with simulation results.
Keywords: MPPT, unity
power factor, backstepping controller, Lyapunov
Issue 2, Volume 6,
April 2011
Title of the Paper: Modeling and
Stability Analysis of AC-DC Power System with Controlled Rectifier and
Constant Power Loads
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Authors: K.
Chaijarurnudomrung, K.-N. Areerak, K.-L. Areerak
Abstract: Power converters with their controls normally behave as a constant
power load. This load can significantly degrade the system stability.
Therefore, the system dynamic model is very importance because it can be used
for stability analysis. It is well known that power converter models are
time-varying because of their switching behaviours. This paper presents the DQ
modeling method to eliminate the switching action to achieve time-invariant
model for the stability analysis. The power system studied is the AC
distribution system. The small-signal model of the power system is obtained by
using a linearization technique. The small-signal simulations are used to
validate the DQ linearized model. The reported model is then used for the
stability analysis via the classical control theory. The results show that an
excellent agreement between the mathematical model and the three-phase
benchmark model is achieved.
Keywords: Constant power
loads, DQ method, simulation, modeling, controlled rectifier, stability
analysis
Title of the Paper: Wavelet Entropy
Based Algorithm for Fault Detection and Classification in FACTS Compensated
Transmission Line
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Authors: Amany M.
El-Zonkoly, Hussein Desouki
Abstract: Distance protection of transmission lines including advanced
flexible AC transmission system (FACTS) devices has been a very challenging
task. FACTS devices of interest in this paper are static synchronous series
compensators (SSSC) and unified power flow controller (UPFC). In this paper, a
new and simple algorithm is proposed to detect and classify the fault and
identify the fault position in a transmission line with respect to a FACTS
device placed in the midpoint of the transmission line. The algorithm is
suitable for the analysis of different types of faults. Discrete wavelet
transformation and wavelet entropy calculations are used to analyze during
fault current and voltage signals of the compensated transmission line. The
proposed algorithm is very simple and accurate in fault detection and
classification. A variety of fault cases and simulation results are introduced
to show the effectiveness of such algorithm.
Keywords: Fault detection;
Power systems; Wavelet transform; Entropy calculation; FACTS; SSSC; UPFC
Title of the Paper: The Influence of
Static Contactor on the THD Generated by Currents on a High Frequency Electro
Thermal Installation with Electromagnetic Induction
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Authors: Raluca Rob,
Ioan Sora, Caius Panoiu, Manuela Panoiu
Abstract: This paper presents an analysis of the electrical parameters
resulted during the functioning simulation of a high frequency electro thermal
installation with electromagnetic induction. Modeling and simulation the
electrical scheme were made using PSCAD-EMTDC tool. The authors followed the
influence of the static contactor regarding the THD generated by phase
currents in secondary winding of power transformer.
Keywords: Electro thermal
installation, electromagnetic induction, harmonic distortion
Issue 3, Volume 6,
July 2011
Title of the Paper: Active Power
Influence on the Electrical Parameters of an Electro Thermal Installation with
Electromagnetic Induction
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Authors: Caius Panoiu,
Raluca Rob, Manuela Panoiu, Gabriel Popa
Abstract: In this paper followed the variation of the electrical parameters
that characterize the functioning of an electro thermal installation with
electromagnetic induction. The measurements were made using a three phase
power quality analyzer, CA 8334B. There were presented two different
situations: the HF transformer with 5:1 and 3:1 transformation ratio. In order
to recover the recordings, the transients, the alarms and the screen copies,
there was used the QualiStar View software.
Keywords: Electro thermal
installation, electrical parameters
Title of the Paper: The V-CURVE
Analysis and Study of Synchronous Motors Using MATLAB Program
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Authors: Aree A.
Muhammad
Abstract: Today Synchronous motors are widely used in modern societies:
industrial, commercial, agricultural, and domestic applications as
constant-speed motors or as compensators for reactive power control in large
power systems. Also understanding the machine’s behaviour and determining its
equivalent network and performance characteristics are of prime importance to
a power engineer. This paper explains the constructional features and
operating principles of the synchronous motor performance, the effects of load
and field excitation on the synchronous motor are investigated. The V-curve of
a synchronous machine is analysed, studied, and a review of various excitation
systems provided. MATLAB program is used to verify this study.
Keywords: Synchronous
motor, over excitation, vector diagrams, V-curves
Title of the Paper: Line Configuration
Analysis of an Overhead Ground Wire the Effect of Electric Fields Distribution
around the HV Power Transmission Line Using Finite Element Method
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Authors: P. Pao-La-Or,
W. Ongsanthea
Abstract: This paper has proposed a mathematical model of electric fields
caused by high voltage (HV) conductors of electric power transmission systems
by using a set of second-order partial differential equations (PDE). This
study has considered line configuration of an overhead ground wire (OHGW) the
effect on electric fields emitted around a 500-kV power transmission line.
Comparison among seven test cases configuration, varying height of OHGW,
varying distance between two-line of OHGW and varying size of OHGW, has been
illustrated. Computer-based simulation utilizing the two-dimensional finite
element method (FEM) in the time harmonic mode, instructed in MATLAB
programming environment with graphical representation for electric field
strength has been investigated. From all test cases, the calculation line of
1.0 m above the ground level is set to investigate the electric fields acting
on a human.
Keywords: Overhead Ground
Wire (OHGW), Line Configuration, Electric Field, Finite Element Method (FEM),
Transmission Line
Issue 4, Volume 6,
October 2011
Title of the Paper: Design and
Simulation of Stand Alone Photovoltaic Systems
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Authors: Salima Kebaili,
Achour Betka
Abstract: This paper presents the design and simulation of a stand alone
photovoltaic system. The main activities of this work purpose to establish
library mathematical models for each individual component of stand alone
photovoltaic system. Control strategy has been considered to achieve permanent
power supply to the load via photovoltaic/battery based on the power available
from the sun. The complete model was simulated under two testing including
sunny and cloudy conditions.
Keywords: Renewable
energy, Photovoltaic system, Lead-acid battery, Modeling, Control, Simulation
Title of the Paper: PI, PID and Fuzzy
Logic Controlled Cascaded Voltage Source Inverter based Active Filter for
Power Line Conditioners
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Authors: Karuppanan P.,
Kamalakanta Mahapatra
Abstract: This paper presents a PI, PID and Fuzzy Logic Controller (FLC) based
shunt active filter for power line conditioners (PLC) to improve the power
quality in the distribution network. This active power filter is implemented
with current controlled cascaded multilevel voltage source inverter (VSI). It
is connected at the point of common coupling for compensating harmonic and
reactive power by injecting equal but opposite harmonic compensating currents.
The reference current extraction is based on sensing main currents only, which
require current harmonics and reactive volt-ampere compensation. The PI or PID
or fuzzy logic controller is used to estimates the peak reference current by
controlling the dc-bus capacitor voltage of the cascaded inverter. The
cascaded multilevel inverter switching signals are derivates from
triangular-sampling current controller; it gives a good dynamic performance
under steady state and transient operations. The cascaded active filter system
is validated through extensive simulation under steady state and transient
conditions with different non-linear loads. These simulation results have been
revealed that the cascaded active power filter performs perfectly in
conjunction with PI or PID or FLC. A comparative assessment of these three
different controllers is disclosed.
Keywords: Active Power
Line Conditioners (APLC), PI and PID Controller, Fuzzy Logic Controller (FLC),
Triangular-Sampling current controller, Harmonics, Power quality
Title of the Paper: Energy Based
Control Strategy for the Reduction in the Response Time of DSTACOM
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Authors: Sakshi Bangia,
P. R. Sharma, Maneesha Garg
Abstract: This paper studies the timely issue of response of Distribution
Static Compensator when there is reduction in AC and DC loads. DSTACOM is an
important device in correcting power quality problems like harmonics
reduction, load balancing, reactive power compensation etc. The energy stored
in its dc capacitor releases during transients to provide ride through to
facilitate load shedding. .The presented algorithm evaluates the reduction in
response time of dstatcom based on energy of capacitor rather than voltage.
And it is compared with conventional algorithm which regulate the voltage of
the capacitor, mainly depends on the values of PI parameters. It is observed
that ratio of gains of proportional to integral controller is many times
larger in case of new scheme introduced here .Thus the effect of sudden power
loss is investigated with and without the DSTATCOM connection and concluded
that response time reduces from 0.04 sec to 0.01 sec The present approach is
validated through simulations using MATLAB software with its Simulink and
Power System Block set (PSB) toolboxes and then graphical programming of
LabVIEW software has been utilized to develop analyzer and also to monitor the
results . Use of virtual instrumentation for the measurement and monitoring
power system improves the performance and reliability of the system.
Keywords: DSTATCOM,
transient time, voltage source converter, THD reduction, LABVIEW
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