|
A
recursive wavelet transform analysis of earth fault currents in |
|
Petersen-coil-protected
power distribution networks |
|
Time-Frequency
and Time-Scale Analysis, 1994., Proceedings of the IEEE-SP |
|
International
Symposium on , 1994 |
|
Earth-phase
faults are the most frequent faults likely to occur in a power
distribution |
|
network.
In the case of Petersen-coil-protected power networks, meaningful
information |
|
is
contained in the transient fault signals and should be used in the
protections to increase |
|
their
speed and accuracy. An earth-phase fault is simulated with EMTP (ElectroMagnetic |
|
Transient
Program). Then, a recursive wavelet transform is applied on two kinds of
fault |
|
currents
that are the zero-sequence currents in the faulty feeder and in the
healthy one. |
|
The
instantaneous time-frequency information obtained may be useful for the
design of a |
|
A
new approach to fast fault detection in power systems |
|
Aravena,
J.L.; Chowdhury, F.N. |
|
Intelligent
Systems Applications to Power Systems, 1996. Proceedings, ISAP '96., |
|
International
Conference on , 1996 |
|
This
paper presents an integrated approach to the problem of power system fast
fault |
|
detection
and isolation. The idea is to use concepts from signal processing and
wavelet |
|
theory
to create fast and sensitive fault indicators. The indicators can then be
analyzed by |
|
standard
statistical hypothesis testing or by artificial neural nets to create
intelligent |
|
decision
rules. The approach described in this paper does not depend on the
availability of |
|
an
accurate mathematical model. Hence it is expected to be robust and of wide |
|
applicability.
Results of the analysis of computer simulated faulty transmission lines
using |
|
filter
banks is included.
|
|
Application
of wavelet theory to power distribution systems for fault detection |
|
Intelligent
Systems Applications to Power Systems, 1996. Proceedings, ISAP '96., |
|
International
Conference on , 1996 |
|
In
this paper, an investigation of the wavelet transform as a means of
creating a feature |
|
extractor
for artificial neural network (ANN) training is presented for application
to |
|
distribution
network fault location. The study includes a terrestrial-based three-phase |
|
delta-delta
power distribution system. Faults were injected into the system and data
was |
|
obtained
from experimentation. Graphical representations of the feature extractors |
|
obtained
in the time domain, the frequency domain and the wavelet domain are
presented |
|
to
ascertain the superiority of the wavelet transform feature extractor.
|
|
Classification
of power distribution system fault currents using wavelets |
|
associated
to artificial neural networks |
|
Assef,
Y.; Chaari, O.; Meunier, M. |
|
Time-Frequency
and Time-Scale Analysis, 1996., Proceedings of the IEEE-SP |
|
International
Symposium on , 1996 |
|
In a
power distribution system with a resonant neutral grounding, traditional
protection |
|
algorithms
based on a steady state analysis are no longer adapted. Hence a good use
of |
|
transients
becomes essential. This paper deals with the possibility of using wavelet |
|
transform
as a preprocess for artificial neural networks (ANN) in the algorithm of
power |
|
system
relays. The ANN decides, after training, if the measured signal is faulty
or sound. |
|
The
inputs of the ANN are the arguments of wavelet coefficients obtained after
applying |
|
a
recursive wavelet transform on faulty signals generated with EMTP (ElectroMagnetic |
|
Transient
Program). A comparison between the wavelets and fast Fourier transform has |
|
Wavelet
transform analysis of arrester voltage in surge motor protection |
|
Islam,
M.S.; Samra, A.H.; Andrian, J. |
|
Southeastcon
'96. Bringing Together Education, Science and Technology., Proceedings of |
|
Studies
showed that most motors stator winding failures result from the breakdown
of the |
|
turn
insulation during switching or lightning surges. Failure would be less
frequent if |
|
motors
were properly protected against such surges. Meaningful information is
contained |
|
in the
transient surge signals and should be used in the protection algorithm to
increase |
|
their
speed and accuracy. In this paper, the Electromagnetic Transient Program (EMTP) |
|
is
used to simulate surge arrester behaviour during switching. The multiscale
wavelet |
|
transform
is then applied to the voltage waveform across the terminals of an
induction |
|
motor.
The instantaneous time-frequency information obtained may be useful for
the |
|
design
of a fast and accurate relay algorithm.
|
|
Wavelets:
a new tool for the resonant grounded power distribution systems |
|
Chaari,
O.; Meunier, M.; Brouaye, F. |
|
Power
Delivery, IEEE Transactions on , Volume: 11 Issue: 3 , July 1996 |
|
This
paper introduces wavelets and shows that they may be efficient and useful
for |
|
power
distribution relaying. The wavelet transform of a signal consists in
measuring the |
|
"similarity"between
the signal and a set of translated and scaled versions of a "mother |
|
wavelet".
The "mother wavelet" is a chosen fast decaying oscillation
function. Wavelets |
|
are
used to analyse transient earth faults in a 20 kV resonant grounded
network as |
|
generated
by EMTP. It is shown that wavelets may be employed for analysing records
to |
|
study
efficiently the faulted network. Moreover, this new technique can actually
be |
|
implemented
in real time for protection devices. Thus, it is suitable for application
to |
|
A
new technique using wavelet analysis for fault location |
|
Xia
Yibin; David Chan Tat Wai; Keerthipala, W.W.L. |
|
Developments
in Power System Protection, Sixth International Conference on (Conf. |
|
A new
technique employing wavelet transform (WT) is proposed for fault location. |
|
Dyadic
wavelet analysis is implemented by way of the multiresolution filter banks.
A |
|
six-level
filter bank is constructed to abstract the fundamental frequency voltage
and |
|
current
signals from the faulted transmission line. Fault location is then
calculated using |
|
the
clean sinusoidal waveform obtained. Fault simulations are performed using
EMTP, |
|
and
results demonstrated the WT method is more accurate as compared to the
Fourier |
|
A
new principle of discrimination between inrush current and internal short |
|
circuit
of transformer based on fuzzy sets |
|
Shaohua
Jiao; Wanshun Liu; Peipu Su; Qixun Yang; Zhenhua Zhang; Jianfei Liu |
|
Power
System Technology, 1998. Proceedings. POWERCON '98. 1998 International |
|
Conference
on , Volume: 2 , 1998 |
|
Page(s):
1086 -1090 vol.2 |
|
A
criterion of extracting the dead angle characteristic of the power
transformer based on |
|
the
wavelet is presented in the paper. Another criterion of extracting the
symmetry |
|
feature
of the internal fault current waveform based on an integral algorithm is
also |
|
proposed.
The fuzzy math models and the integral principle used to discriminate the
inrush |
|
current
and the fault current are developed in the paper based on these criteria.
All the |
|
conclusions
are verified by the EMTP and the electric power system simulation lab of |
|
NCEPU
and proved to be highly accurate and fast.
|
|
A
novel technique for high impedance fault identification |
|
David
Chan Tat Wai; Xia Yibin |
|
Power
Delivery, IEEE Transactions on , Volume: 13 Issue: 3 , July 1998 |
|
A
novel technique using wavelet analysis filter banks (WAFB) to identify
distribution high |
|
impedance
faults (HIFs) is presented. A new model of HIF is used. HIFs and capacitor |
|
bank
switching operations are simulated by the Electromagnetic Transients
Program |
|
(EMTP)
and their current signals are studied. High frequency components with the
time |
|
localization
information of both HIFs and capacitor bank switching operations are
obtained |
|
using
WAFB and their behavior is differentiated clearly. Results demonstrate
that |
|
WAFB
can be used as an element in a HIF detector for fast and accurate
identification |
|
A
wavelet multiresolution analysis approach to fault detection and
classification |
|
J.
Liang, S. Elangovan and J.B.X. Devotta |
|
International
Journal of Electrical Power and Energy Systems 20 6 (1998), pp. 327¯332 |
|
A
real-time wavelet multiresolution analysis (MRA)-based fault detection and |
|
classification
algorithm is proposed in this paper. The first stage MRA detail signals |
|
extracted
from the original signals are used as the criteria for this problem. By
measuring |
|
the
sharp variation values of the MRA detail signals, faults in the power
system can be |
|
detected.
The fault type is then identified by the comparison of the three-phase MRA |
|
sharp
variations. The effects of the fault distance, fault inception angle and
fault |
|
impedance
are examined, and the fault classification routine is designed to overcome
their |
|
effects.
Simulation results show that this algorithm is effective and robust, and
it is |
|
promising
in high impedance fault detection.
|
|
Application
of discrete wavelet transform to high impedance fault identification |
|
Lai,
L.L.; Styvaktakis, E.; Sichanie, A.G. |
|
Energy
Management and Power Delivery, 1998. Proceedings of EMPD '98. 1998 |
|
International
Conference on , Volume: 2 , 1998 |
|
This
paper describes the application of discrete wavelet transforms to power
system |
|
high-impedance
fault identification. Fault simulation is carried out with the EMTP96 |
|
software
package. Results demonstrate that there is a high potential in the use of
this |
|
technique
to distance relaying. |
|
Data
smoothing by B-spline wavelets for digital distance protection |
|
Yuan
Liao and S Elangovan |
|
International
Journal of Electrical Power & Energy Systems, Volume 20, Issue 4, May |
|
The
multiresolution analysis generated by the compactly supported cardinal B-spline |
|
wavelets
for data smoothing is introduced. It is shown that the proposed technique
has the |
|
advantages
of high accuracy and low delay and may be used instead of the traditional |
|
low-pass
filters for power system protection. Its applications in digital distance
protection |
|
are
presented in detail. Simulation studies using EMTP have shown that the |
|
wavelets-based
method can reduce the relaying time and may be suitable for digital |
|
Development
of novel adaptive single-pole autoreclosure schemes for extra high |
|
voltage
transmission systems using wavelet transform analysis |
|
Electric
Power Systems Research, Volume 47, Issue 1, October 1998, Pages 11-19 |
|
A
novel wavelet transform analysis-based adaptive single-pole autoreclosure
(SPAR) |
|
scheme
of extra high voltage (EHV) transmission systems is presented in this
paper. The |
|
discrete
wavelet transform is adopted to analyse the fault transients caused by the |
|
secondary
arc and permanent faults and the numerical results reveal that certain
wavelet |
|
components
can be effectively used to detect and identify the fault relevant |
|
characteristics
in transmission systems. A threshold-based decision logic for the wavelet |
|
analysis
coefficients is used to distinguish the transient and permanent faults,
and in the |
|
case
of a transient fault, to determine the secondary arc extinction time. The
outcome of |
|
the
study clearly indicates that the wavelet transform analysis technique can
be used as |
|
an
attractive and effective means of developing an adaptive autoreclosing
scheme.
|
|
DSP
implementation of a wavelet analysis filter bank for high impedance fault |
|
Xia
Yibin; Qi Li; Chan, D.T.W. |
|
Energy
Management and Power Delivery, 1998. Proceedings of EMPD '98. 1998 |
|
International
Conference on , Volume: 2 , 1998 |
|
The
real-time digital signal processing (DSP) implementation of a wavelet
analysis filter |
|
bank (WAFB)
to identify a high impedance fault (HIF) is presented. HIFs and capacitor |
|
bank
switching events are simulated by using the Electromagnetic Transients
Program |
|
(EMTP).
The simulation results are used as the input signal for the implementation
of a |
|
wavelet
analysis filter bank. Results demonstrate that the wavelet analysis filter
can be |
|
used
as an element in a real-time HIF detector for fast and accurate
identification of |
|
Fault
location using wavelets |
|
Power
Delivery, IEEE Transactions on , Volume: 13 Issue: 4 , Oct. 1998 |
|
This
paper describes the use of wavelet transforms for analyzing power system
fault |
|
transients
in order to determine the fault location. Traveling wave theory is
utilized in |
|
capturing
the travel time of the transients along the monitored lines between the
fault point |
|
and
the relay. Time resolution for the high frequency components of the fault
transients, |
|
is
provided by the wavelet transform. This information is related to the
travel time of the |
|
signals
which are already decomposed into their modal components. The aerial mode
is |
|
used
for all fault types, whereas the ground mode is used to resolve problems
associated |
|
with
certain special cases. The wavelet transform is found to be an excellent
discriminant |
|
for
identifying the traveling wave reflections from the fault, irrespective of
the fault type |
|
and
impedance. EMTP simulations are used to test and validate the proposed
fault |
|
location
approach for typical power system faults.
|
|
Multiresolution
signal decomposition: a new tool for fault detection in power |
|
transformers
during impulse tests |
|
Power
Delivery, IEEE Transactions on , Volume: 13 Issue: 4 , Oct. 1998 |
|
Detection
of major faults in power transformers during impulse tests has never been
an |
|
issue,
but is rather difficult when only a minor fault, say a sparkover between
adjacent |
|
coils
or turns and lasting for a few microseconds, occurs. However, detection of
such a |
|
type
of fault is very important to avoid any catastrophic situation. In this
paper, the |
|
authors
propose a new and powerful method capable of detecting minor incipient
faults. |
|
The
approach is based on wavelet transform analysis, particularly the dyadic-orthonormal |
|
wavelet
transform. The key idea underlying the approach is to decompose a given
faulty |
|
neutral
current response into other signals which represent a smoothed and
detailed |
|
version
of the original. The decomposition is performed by the multiresolution
signal |
|
decomposition
technique. Preliminary simulation work demonstrated here shows that the |
|
proposed
method is robust and far superior to other existing methods to resolve
such types |
|
Study
on wavelet analysis and its application to numerical protection for large |
|
Lin
Tao; Ying Xianggeng; Chen Deshu |
|
Power
System Technology, 1998. Proceedings. POWERCON '98. 1998 International |
|
Conference
on , Volume: 2 , 1998 |
|
Page(s):
1121 -1129 vol.2 |
|
The
definition, applied characteristics as well as fast algorithm of wavelet
transform (WT) |
|
are
introduced in this paper. The designation of WT based high pass (HP), band
pass |
|
(BP)
filters and their applications to numerical protection for large generator
against stator |
|
internal
faults as well as stator earth fault are also presented. Research results
based on |
|
EMTP
simulation and laboratory micromachine experiments show that WT can |
|
effectively
improve the sensitivity and selectivity of traditional numerical
protection |
|
The
wavelet transform applied to distinguish between transient and permanent |
|
Jiang,
F.; Bo, Z.Q.; Yang, Q.X. |
|
Power
System Technology, 1998. Proceedings. POWERCON '98. 1998 International |
|
Conference
on , Volume: 2 , 1998 |
|
Page(s):
1116 -1120 vol.2 |
|
This
paper addresses the application of wavelet transform in the identification
of transient |
|
and
permanent faults by processing the fault generated high frequency current
transient. |
|
The
presented method can be utilised to achieve adaptive reclosure which means
only the |
|
transient
fault can activate the reclosing operation. An identification unit is
designed to |
|
capture
the high frequency component generated by a fault arc and the wavelet
transform |
|
is
used to extract the high frequency noise generated by the fault arc and
distinguish |
|
between
the transient and permanent fault.
|
|
Travelling
wave fault location of transmission line using wavelet transform |
|
Qin
Jian; Chen Xiangxun; Zheng Jianchao |
|
Power
System Technology, 1998. Proceedings. POWERCON '98. 1998 International |
|
Conference
on , Volume: 1 , 1998 |
|
This
paper presents a new fault location principle based on the double terminal
methods of |
|
travelling
waves using continuous wavelet transform (CWT). Due to the attenuation and |
|
distortion
of travelling wave propagation in a transmission line, a open problem is
how to |
|
define
the arrival time and the propagation velocity of the travelling wave
correctly. Since |
|
CWT
has much better resolution for locating a transient event in time-domain,
the arrival |
|
time
can be defined by a characteristic point of the travelling wave extracted
by a suitable |
|
continuous
wavelet with the optimal dilation parameters, and the propagation velocity |
|
depends
on the physical configuration of a transmission line and the optimal
dilation |
|
parameters.
Extensive simulation results show that the new method has a location |
|
accuracy
within /spl plusmn/ one tower span in the case of various grounding
resistances, |
|
different
fault positions and different line configurations.
|
|
Wavelet
analysis and neural networks based adaptive single-pole autoreclosure |
|
scheme
for EHV transmission systems |
|
International
Journal of Electrical Power and Energy Systems 20 7 (1998), pp. 465-474 |
|
This
paper proposes a wavelet analysis and neural network based adaptive
single-pole |
|
autoreclosure
scheme for Extra High Voltage (EHV) transmission systems. First, the |
|
fault
transients generated by the secondary arc and permanent faults are
analysed using |
|
discrete
wavelet transform with particular reference to the development of the
adaptive |
|
autoreclosure
scheme. Daubechies D4 wavelet transform is adopted and the numerical |
|
analyses
reveal that certain wavelet components can be effectively used as the
features |
|
to
detect and identify the fault relevant characteristics in transmission
systems. Several |
|
results
of wavelet analysis are used as the feature vectors of artificial neural
network |
|
which
is designed to distinguish between transient and permanent faults, and to
determine |
|
the
secondary arc extinction point. The outcome of the study clearly indicates
that the |
|
wavelet
analysis combined with neural network approach can be used as an
attractive |
|
and
effective means of realising an adaptive autoreclosing scheme.
|
|
Wavelet
transform and neural network approach to developing adaptive |
|
single-pole
auto-reclosing schemes for EHV transmission systems |
|
IEEE
Power Engineering Review , Volume: 18 Issue: 11 , Nov. 1998 |
|
The
authors adopt the wavelet transform to detect and identify relevant
electrical fault |
|
characteristics
in power transmission systems. They use several components of wavelet |
|
analysis
as input features to a forward neural network to distinguish transient,
permanent |
|
faults
and the secondary arc extinction point.
|
|
A
fault location technique for two and three terminal lines using high
frequency |
|
fault
clearing transients |
|
Styvaktakis,
E.; Bollen, M.H.J.; Gu, I.Y.H. |
|
Electric
Power Engineering, 1999. PowerTech Budapest 99. International Conference
on |
|
This
paper suggests that a voltage recorder, placed next to a circuit breaker
not as usual |
|
on the
side of the substation, but on the side of the transmission line, may
reveal the |
|
location
of permanent faults. Two different approaches on estimating the fault
location |
|
are
presented here: a frequency domain approach and a time domain approach.
These |
|
methods
are tested and compared with simulations of typical transmission systems
using |
|
the
Electromagnetic Transients Program (EMTP). Two typical line configurations
are |
|
considered:
two terminal lines and three terminal lines.
|
|
A
new fault location technique for radial distribution systems based on high |
|
Power
Engineering Society Summer Meeting, 1999. IEEE , Volume: 1 , 1999 |
|
This
paper presents a fault location method for distribution systems. The
method is based |
|
on the
traveling wave theory and uses the transient signals recorded during the
fault, as a |
|
basis
for the analysis. According to the traveling wave theory fault transients
will have |
|
different
signatures at the substation terminals depending on the number of network |
|
junctions
they pass through as they travel towards the substation. Unfortunately,
these |
|
signatures
only show up at high frequency end of the spectrum and will be missed by |
|
most
methods based on the power frequency signals. The proposed method takes |
|
advantage
of the special properties of the wavelet transform to differentiate
between |
|
faults
occuring along different laterals of the same main feeder, equal distance
away from |
|
the
main substation. Once the faulted lateral is identified, exact location of
the fault is |
|
determined
by one of the conventional methods developed for strictly radial systems. |
|
Simulation
results obtained by using ATP/EMTP for a sample distribution system, are |
|
included
for demonstration of the proposed method.
|
|
A
non communication transmission line protection using wavelet transform and |
|
transients
protection technique |
|
F.
Jiang; Z.Q. Beo, Philips S. M. Chin, G. Weller |
|
This
paper describes a new a strategic in with wavelet transform and transients
protection |
|
tecnique
are utilised to protect transimission lines. The presented relaying
technique is |
|
principally
based on the detection of fault generates transient signals with has
wideband of |
|
high
frequency components. The simulation studies is carry out extentensively
by use of |
|
EMPT
and wavelet transform, with source that the proposed algorithm provides
the |
|
possibilities
of high-speed and accurate fault detection. In addition the algorithm
provides |
|
simple
and economic designs for power protection system.
|
|
A
wavelet-based differential transformer protection |
|
Gomez-Morante,
M.; Nicoletti, D.W. |
|
Power
Delivery, IEEE Transactions on , Volume: 14 Issue: 4 , Oct. 1999 |
|
Transformer
inrush currents were traditionally evaluated by means of Fourier analysis. |
|
Such
an approach affects the design of transformer differential relays
concerning their |
|
immunity
to inrush currents. This paper presents a wavelet-based method, which
seems to |
|
provide
a reliable and computationally efficient tool for distinguishing between
internal |
|
faults
and inrush currents.
|
|
An
approach using wavelet transform for fault type identification in digital |
|
Silveira,
P.M.; Seara, R.; Zurn, H.H. |
|
Power
Engineering Society Summer Meeting, 1999. IEEE , Volume: 2 , 1999 |
|
This
paper proposes the use of wavelet transform (WT) in power transmission
lines for |
|
identifying
fault types. WT multiresolution properties are quite adequate for
detection of |
|
fast
changes contained in the disturbed signal. Wavelet decomposition
associated with |
|
modal
components have shown to be an excellent alternative for quick
identification of |
|
faulted
phases. Digitized phase voltage and/or current signals are fed to wavelet
filters. |
|
The
coefficients obtained are then transformed by a modified modal
transformation |
|
matrix.
From the resulting signals, the energy is measured with short time
intervals. With |
|
an
appropriately chosen threshold the fault type is identified. EMTP
simulations are used |
|
to
test and validate the proposed methodology. The obtained results are
encouraging and |
|
the
proposed technique requires a low computational complexity, allowing it to
be used as |
|
part
of a high speed protective relay.
|
|
Comparison
of wavelet and differential equation algorithms in earth fault distance |
|
S.
Hanninen, M. Lehtonen, T. Hakola, R. Rantanen |
|
This
paper gives a comparison between wavelet analysis and a differential
equation |
|
algorithm
in transient based earth fault location in the 20 kV radial distribution
networks. |
|
The
items discussed are earth fault transients, signal pre-processing and the
performance |
|
of the
proposed distancce estimation algorithms. The networks considered are
either |
|
uneathed
or resonant earthed. The comparison showed that both algorithms were equal. |
|
The
mean error in fault location was 12% in the field tests using staged
faults which were |
|
recorded
in real power systems.
|
|
Detection
of Transformer Winding Faults Using Wavelet Analysis and Neural |
|
Hang
Wang, Karen L. Butler |
|
This
paper investigates the application of wavelet transform as a preprocessor
for neural |
|
networks
(NN) inidentifying internal turn-to-turn faults in transformer windings.
|
|
Experimental
study for transient phenomena of ground faults on distribution |
|
lines
based on various fault causes |
|
Tungkanawanich,
A.; Kawasaki, Z.-I.; Matsuura, K.; Kuno, H. |
|
Electric
Power Engineering, 1999. PowerTech Budapest 99. International Conference
on |
|
Transients
normally contain information that is helpful to diagnose the cause and
aspect of |
|
the
fault. This experiment is conducted with the objective of studying the
basic |
|
knowledge
of fault features and hopefully useful to get more precise in
discriminating fault |
|
causes.
Ground faults are concentrated in this paper because they are known as the
most |
|
frequent
ones occurring on distribution lines. The results are compared with those
from |
|
actual
fault and computer simulation. The authors also conduct the time-frequency |
|
analysis
of dynamic spectrum of transients of various fault causes by means of
wavelet |
|
transform
for explaining fault phenomena.
|
|
High-impedance
fault detection utilizing a Morlet wavelet transform approach |
|
Shyh-Jier
Huang; Cheng-Tao Hsieh |
|
Power
Delivery, IEEE Transactions on , Volume: 14 Issue: 4 , Oct. 1999 |
|
An
application of Morlet wavelets to the analysis of high-impedance fault
generated |
|
signals
is proposed in this paper. With the time-frequency localization
characteristics |
|
embedded
in wavelets, the time and frequency information of a waveform can be |
|
presented
as a visualized scheme. Different from the fast Fourier transform, the
wavelet |
|
transform
approach is more efficient in monitoring fault signals as time varies. The |
|
proposed
method has been applied to discriminate the high-impedance faults from the |
|
normal
switching events, and to examine the faults under various grounds
including |
|
Portland
cement, wet soil and grass. Testing results have demonstrated the
practicality |
|
and
advantages of the proposed method for the applications.
|
|
Wavelet
transforms for distance protection |
|
H. J.
Koglin, T. Lobos, J. Rezner |
|
When a
ground fault occurs, the measured voltage waveform contain significant |
|
oscillatory
transient components. The basis component of short circuit current can be |
|
distorted
by and exponential dc component. In some situation, time constants of the |
|
decaying
higher frequency componets may reach values up to 100 ms. It is difficult
to |
|
filter
out such components with out delay the filter response. In the paper
application of |
|
complex
wavelets are investigated. Firts, phasor of distorted currents and
voltages are |
|
estimated.
Transients responses of the wavelet algorithms are compared to that of the |
|
fourier
ones. Front the phasor, the impedance of the protected line is calculated. |
|
Monotonous
transients behaviour of the estimated impedance makes it possible to
predict |
|
the
desired parameters of a protected line even during a transient state.
|
|
A
B-Spline Wavelet Based Fault Classification Scheme for High Speed |
|
CHENG
HONG; S. ELANGOVAN; |
|
Electric
Machines and Power Systems, 28:313–324, 2000 |
|
Copyright
c s2000 Taylor & Francis |
|
This
paper presents a new fault detection and classi”cation algorithm based |
|
on the
wavelet transform. The B-spline wavelet transforms of three phase cur-rents |
|
on
transmission lines are employed. By comparing the moving average of |
|
these
transforms, fault types are classi”ed easily. EOEects of the fault
inception |
|
angle,
fault distance, and fault impedance are examined. Simulation studies |
|
using
EMTP show that the wavelet-based algorithm is simple, eOEective, and |
|
robust.
Without any modi”cation, the proposed algorithm can be applied to |
|
power
systems of any voltage level. It is suitable for the high-speed protection |
|
A
new approach to high impedance fault detection using wavelet packet
analysis |
|
Lazkano,
A.; Ruiz, J.; Aramendi, E.; Leturiondo, L.A. |
|
Harmonics
and Quality of Power, 2000. Proceedings. Ninth International Conference on
, |
|
Page(s):
1005 -1010 vol.3 |
|
The
paper presents a new approach to high impedance fault detection based on
wavelet |
|
packet
analysis. The nature and dynamics of the arc phenomenon related to high |
|
impedance
faults are analyzed. A background is reported about wavelet transform and |
|
wavelet
packet decomposition. Then, detecting criteria are proposed and assessing |
|
parameters
calculated. Finally, in order to evaluate the procedure, the approach is
applied |
|
to
power system signals in normal conditions.
|
|
A
new paradigm for impulse testing of power transformers |
|
Vanaja,
R.; Udayakumar, K. |
|
Power
Engineering Society Winter Meeting, 2000. IEEE , Volume: 3 , 2000 |
|
Page(s):
2206 -2210 vol.3 |
|
Reliable
methods for sensitive detection of internal defects in the insulation
system of a |
|
power
transformer during impulse test, are still an active area of research. A
new impulse |
|
analysing
system for a power transformer is discussed. It is based on recognising
the |
|
possible
nature of winding fault using the temporal records, transfer function and
high |
|
frequency
spectra. The neutral current, transferred surge current, capacitively
transferred |
|
current,
could be analyzed using these approaches. But for the analysis of
interturn |
|
discharges
and occurrence of partial discharges which are fast decaying signals it
has |
|
been
observed that application of the wavelet transforms would be more
appropriate. This |
|
paper
discusses methods of analyzing some of the winding faults using signal
processing |
|
A
Novel method for large turbine generator protection based on wavelet |
|
Wu
Guopei; Guan, L.; Ren Zhen; Huang Qungu |
|
Advances
in Power System Control, Operation and Management, 2000. APSCOM-00. |
|
2000
International Conference on , Volume: 1 , 2000 |
|
The
frequency property of wavelet transformation (WT) has been studied in
depth in this |
|
paper
with comparision with the discrete fourier transform (DFT). The band
overlapping |
|
and
frequency leakage among different scales of WT is discussed. Several new
wavelet |
|
functions
with compact-supported property in frequency domain are constructed. A |
|
general
process for selecting proper wavelet functions according to practical
requirements |
|
is
proposed. A novel WT based method is developed to detect generator inner
faults. |
|
Comparing
with the DFT method, the Wt based signal analysis requires no frequency |
|
tracking
and is not affected by frequency deviation. No leakage frequency occur
with the |
|
new
methos applied. Simulation results probe the feasibility and advantages of
the new |
|
method
presented for the paper.
|
|
A
wavelet transform based decision making logic method for discrimination |
|
between
internal faults and inrush currents in power transformers |
|
P. L.
Mao and R. K. Aggarwal |
|
International
Journal of Electrical Power & Energy Systems, Volume 22, Issue 6,
August |
|
This
paper describes a decision making logic method for discrimination between
internal |
|
faults
and inrush currents in power transformers using the wavelet transform
based |
|
feature
extraction technique. It is shown that the features extracted by the
wavelet |
|
transform
have a more distinctive property than those extracted by the fast Fourier |
|
transform
due to the good time and frequency localisation characteristics of the
wavelet |
|
transform.
As a result, by quantifying the extracted features, the decision for |
|
distinguishing
an internal fault from an inrush current in different power transformer |
|
systems
can be accurately made. The extensive simulation studies have verified
that the |
|
proposed
method is more reliable and simpler, and is suitable for different power |
|
A
wavelet-based method to discriminate between inrush current and internal |
|
Power
System Technology, 2000. Proceedings. PowerCon 2000. International |
|
Conference
on , Volume: 2 , 2000 |
|
With
the development of power systems, the content of the second harmonic
current can |
|
be
comparable to that produced in the inrush current. The conventionally used
second |
|
harmonic
current restrained method becomes unreliable for transformer protection.
To |
|
obtain
some new approaches on discrimination between inrush current and internal
fault, |
|
transformer
models with enough precision of computing inrush current and short-circuit |
|
current
are firstly described. After that, Daubechies family wavelets are selected
as a |
|
mother
wavelet to analyze the inrush current and short-circuit current. The
results show |
|
that
the characteristics of inrush current are significantly different from
those of |
|
short-circuit
current. Based on the analyzing result, the back-propagation neural
network |
|
is
trained to discriminate the inrush current and short-circuit current. The
training results |
|
presented
in this paper show that wavelet based discrimination method is efficient
with |
|
good
performance and reliability.
|
|
Accelerated
trip of power transmission line based on biorthogonal wavelet |
|
Shi,
T.H.; Zhang, H.; Liu, P.; Zhang, D.J.; Wu, Q.H. |
|
Power
Engineering Society Summer Meeting, 2000. IEEE , Volume: 3 , 2000 |
|
Page(s):
1333 -1337 vol. 3 |
|
This
paper presents a novel approach to accelerated trip of power transmission
lines using |
|
biorthogonal
wavelet transform to improve the performance of protection relays. The |
|
existing
principle derived from the second abrupt changes of the sequence currents
to |
|
accelerate
trip has been widely applied, while a fault occurs in the second zone of
the |
|
distance
protection. However, a lower sensitivity has been observed for some
specific |
|
system
parameters and fault types for which the second abrupt changes of sequence |
|
currents
are particularly faint. The wavelet analysis has an outstanding
characteristics to |
|
extract
signal components, by contrast to the conventional Fourier analysis which
is |
|
inefficient
to detect the faint abrupt signal. A fourth-order biorthogonal wavelet |
|
decomposition
algorithm is proposed in this paper, which possesses the capability of
fast |
|
calculation,
partitioning the higher frequency band and linear phase. This algorithm, |
|
provided
as an accelerated trip scheme, can efficiently extract the faint second
abrupt |
|
changes
of the sequence currents and is able to deal with the dead-zone problem of |
|
conventional
protection techniques. The simulation result obtained using |
|
MATLAB/SIMULINK
shows the feasibility and efficiency of the proposed approach.
|
|
Application
of wavelet transform in travelling wave protection |
|
J.
Liang, S. Elangovan and J. B. X. Devotta |
|
International
Journal of Electrical Power & Energy Systems, Volume 22, Issue 8, 1 |
|
November
2000, Pages 537-542 |
|
In
this paper, the correlation function-based travelling wave protection
algorithm is |
|
analysed
from the viewpoint of wavelet transform (WT), and a wavelet correlation |
|
function
(WCF) algorithm is proposed to replace it. In the new algorithm, the multi-scale |
|
spline
WT is used to detect the edges of the travelling wave signal, and the WCF
is then |
|
employed
to fulfil the correlation operation in the WT domain instead of the time
domain. |
|
This
enhances the peak intensity and the noise rejection ability of the
algorithm. The |
|
performance
of this algorithm is illustrated by simulation results.
|
|
Arcing
fault detection in underground distribution networks-feasibility study |
|
Charytoniuk,
W.; Wei-Jen Lee; Mo-Shing Chen; Cultrera, J.; Theodore Maffetone |
|
Industry
Applications, IEEE Transactions on , Volume: 36 Issue: 6 , Nov.-Dec. 2000 |
|
In
some circumstances, arcing faults on insulated low-voltage conductors can
sustain or |
|
reignite
intermittently for several or even several dozen minutes, generating large
amounts |
|
of
heat and gases. In underground secondary distribution cables in ducts, the |
|
decomposition
gases escape to the ends of the duct, typically manholes, where they can |
|
ignite
fire or explode, throwing out the manhole cover. Detection of arcing
faults may be |
|
difficult
using standard overcurrent protections because some arcing faults generate |
|
relatively
low currents. To study the feasibility of detecting arcing faults in
underground |
|
networks,
personnel from Consolidated Edison Company of New York, Inc., New York, |
|
NY,
conducted an experiment in one secondary network by staging arcing faults
and |
|
collecting
data at the fault location and several nearby vaults. The data were
analyzed to |
|
examine
the feasibility of developing a detection algorithm. This paper presents
some |
|
results
of this analysis in time, frequency, and time-frequency domains.
|
|
Comparison
of artificial neural networks and conventional algorithms in ground |
|
fault
distance computation |
|
Eberl,
G.; Hanninen, S.; Lehtonen, M.; Schegner, P. |
|
Power
Engineering Society Winter Meeting, 2000. IEEE , Volume: 3 , 2000 |
|
Page(s):
1991 -1996 vol.3 |
|
This
paper gives a comparison between an artificial neural network method and a |
|
differential
equation algorithm and wavelet algorithm in transient based earth fault
location |
|
in the
20 kV radial power distribution networks. The items discussed are earth
fault |
|
transients.
Signal pre-processing and the performance of the proposed distance
estimation |
|
methods.
The networks considered are either unearthed or resonant earthed. The |
|
comparison
showed that the neural network algorithm was better than the conventional |
|
algorithms
in the case of very low fault resistance. The mean error in fault location
was |
|
about
1 km in the field tests using staged faults, which were recorded in real
power |
|
systems.
With higher fault resistances, the conventional algorithms worked better.
|
|
Effective
transmission line fault detection during power swing with wavelet |
|
Xiangning
Lin; Pei Liu; Shijie Cheng |
|
Power
Engineering Society Winter Meeting, 2000. IEEE , Volume: 3 , 2000 |
|
Page(s):
1950 -1955 vol.3 |
|
A new
scheme for fault identification during power swings is proposed in this
paper. The |
|
new
scheme is based on the orthonormal wavelet transform algorithm. The main |
|
advantage
of the proposed scheme is that fault occurring in the transmission line
can be |
|
correctly
identified during different kinds of power swings. Details of applying the |
|
proposed
scheme in the distance protection are discussed in the paper. The
effectiveness |
|
of the
proposed scheme was verified with the data sampled from an EMTP based |
|
simulator.
Furthermore. As only limited number of real value calculation is needed
for the |
|
proposed
scheme. It is easily realized in real-time applications.
|
|
Fault
location of a teed-network with wavelet transform and neural networks |
|
Lai,
L.L.; Vaseekar, E.; Subasinghe, H.; Rajkumar, N.; Carter, A.; Gwyn, B.J. |
|
Electric
Utility Deregulation and Restructuring and Power Technologies, 2000. |
|
Proceedings.
DRPT 2000. International Conference on , 2000 |
|
A new
technique using wavelet transforms and neural networks for fault location
in a |
|
tee-circuit
is proposed in this paper. Fault simulation is carried out in EMTP96 using
a |
|
frequency
dependent transmission line model. Voltage and current signals are
obtained for |
|
a
single phase (phase-A) to ground fault at every 500 m distance on one of
the branches, |
|
which
is 64.09 km long. Simulation is carried out for 3 cycles (60 ms) with step
size /spl |
|
Delta/t,
of 2.5 /spl mu/s to abstract the high frequency component of the signal
and every |
|
100
points have been selected as output. Two cycles of waveform, covering pre-fault
and |
|
post-fault
information are abstracted for further analysis. These waveforms are then |
|
used
in wavelet analysis to generate the training pattern. Two different mother
wavelets |
|
have
been used to decompose the signal, from which the statistical information
is |
|
abstracted
as the training pattern. RBF network was trained and cross-validated with |
|
Fault
position relay based on current travelling waves and wavelets |
|
Dong
Xinzhou; Ge Yaozhong; Xu Bingyin |
|
Power
Engineering Society Winter Meeting, 2000. IEEE , Volume: 3 , 2000 |
|
Page(s):
1997 -2004 vol.3 |
|
The
current travelling wave is utilized to detect the fault position in the
transmission lines |
|
in
this paper. How to identify the incident travelling waves and reflected
ones from the |
|
fault
point when noises exist is discussed and resolved. A fault position relay
based on |
|
current
travelling waves and wavelets theory is designed. The relay's principle is
mainly |
|
on
wavelet theory and modulus maxima of the wavelet transform. By analyzing
the |
|
distribution
of the modulus maxima, different components in the current travelling
waves |
|
can be
distinguished and then the incident and reflected travelling waves are
identified and |
|
finally
useless components are filtered. The incident and reflected travelling
wave's time |
|
difference
arrival time difference indicates the fault position. An EMTP simulation |
|
example
is illustrated. The relay is been proved correct and effective.
|
|
Improved
technique for fault detection sensitivity in transformer impulse test |
|
Karady,
G.G.; Reta-Hernandez, M.; Amarh, F.; McCulla, G. |
|
Power
Engineering Society Summer Meeting, 2000. IEEE , Volume: 4 , 2000 |
|
Page(s):
2412 -2416 vol. 4 |
|
Insulation
of transformer windings can be damaged by impulse voltages of high
amplitude |
|
produced
by lightning or switching transients. Testing of the windings insulation
is |
|
performed
by using the standard impulse test, generally applying the fast Fourier |
|
transform
(FFT) algorithm to analyze the transformer 'fingerprint' in the frequency |
|
domain.
However, FFT analysis is limited by the spectral leakage and degradation
at |
|
spectral
peaks. To obtain a better signature analysis, this paper investigates the
use of |
|
power
spectral density (PSD) and wavelets analysis techniques. Experimental
results are |
|
shown
from different tests with windings under normal and turn-to-turn short
circuit |
|
conditions
in a single phase transformer.
|
|
Induction
motor mechanical fault simulation and stator current signature analysis |
|
Power
System Technology, 2000. Proceedings. PowerCon 2000. International |
|
Conference
on , Volume: 2 , 2000 |
|
This
paper addresses the simulation of induction machines with mechanical
faults and the |
|
fault
signature analysis of stator current. Models for three-phase induction
motors with |
|
broken
rotor bars by winding function method are developed. Current waveforms of
an |
|
induction
motor under normal and faulty conditions are simulated. New feature |
|
coefficients
for signature analysis of the stator current are proposed based on the
wavelet |
|
packet
decomposition. The feature coefficients are calculated for both normal and
fault |
|
conditions.
If is shown that for most load conditions the new feature coefficients for
fault |
|
cases
are distinctive from normal conditions at certain depth and nodes. The
features |
|
proposed
here can be used for induction motor fault detection and diagnosis.
|
|
Insulation
fault detection in a PWM controlled induction motor-experimental |
|
design
and preliminary results |
|
Wang,
J.; McInerny, S.; Haskew, T. |
|
Harmonics
and Quality of Power, 2000. Proceedings. Ninth International Conference on
, |
|
To
investigate feature extraction methods for early detection of insulation
degradation in |
|
low
voltage (under 600 V), 3-phase, PWM controlled induction motors, a series
of seeded |
|
fault
tests was planned on a 50 HP, 440 V motor. In this paper, the background
and |
|
rationale
for the test plan are described. The instrumentation and test plan are
then |
|
detailed.
Finally, preliminary test experiences are related.
|
|
Power
transformer protection based on transient detection using discrete |
|
Jiang,
F.; Bo, Z.Q.; Chin, P.S.M.; Redfern, M.A.; Chen, Z. |
|
Power
Engineering Society Winter Meeting, 2000. IEEE , Volume: 3 , 2000 |
|
Page(s):
1856 -1861 vol.3 |
|
This
paper addresses a new relaying scheme for power transformer protection. In |
|
principle,
the new technique implements the wavelet transform to extract the
transient |
|
components
from the captured transform currents. The powerful function of a discrete |
|
wavelet
transform (DWT) in analysing nonstatic signals is capable of extracting
those |
|
predominant
transient signals energised by transformer internal fault. With the aid of |
|
spectrum
analysis of extracted transients, the high selectivity of the proposed
relay can be |
|
achieved.
The new relay possesses the advantages of high speed response, immunity to |
|
the CT
saturation, ability of detecting low level internal faults and inrush
current, etc. The |
|
study
in this paper evaluates the performance of the proposed relaying scheme
and |
|
Remote
short-circuit current determination in DC railway systems using wavelet |
|
Chang,
C.S.; Feng, T.; Khambadkone, A.M.; Kumar, S. |
|
Electric
Power Applications, IEE Proceedings- , Volume: 147 Issue: 6 , Nov. 2000 |
|
For
effective protection of DC railway systems, it is important to
discriminate the remote |
|
short-circuit
current from the train starting current. Four methods for the
discrimination |
|
are
assessed. The first two methods apply the traditional heuristics by
comparing the |
|
magnitude
and the rate of change (di/dt) between the two currents. The remaining |
|
methods
use the Fourier and wavelet transforms. It is shown that the first three
methods |
|
do not
provide consistent discrimination. The remote short-circuit current is
determined |
|
mainly
by the steel rail impedance, which is time varying due to the skin effect.
In |
|
contrast,
impedances of the traction motor and the contact wires, and the change of |
|
operating
mode during starting govern the train starting current. The wavelet
transform |
|
identifies
these salient features. The remote short-circuit current is simulated
using |
|
EMTP,
and a SIMULINK model is used to obtain the train starting current.
|
|
Use
of time delays between modal components in wavelet based fault location |
|
A.
Abur and F. H. Magnago |
|
International
Journal of Electrical Power & Energy Systems, Volume 22, Issue 6,
August |
|
This
paper presents an improved fault location method based on the traveling
wave theory |
|
of the
transmission lines. Fault transients recorded at one end of a transmission
line are |
|
processed
to determine the distance from the fault location. Wavelet transform is
utilized |
|
for
this purpose. The proposed method also takes advantage of the different
travel times |
|
of the
modal components in differentiating between close-in and remote end faults.
The |
|
approach
has the advantages of being independent of the fault impedance, mutual |
|
coupling
effects and series compensation capacitors. The method's performance for |
|
typical
faults is illustrated using transient simulations obtained by an
electromagnetic |
|
Wavelet
analysis based scheme for fault detection and classification in |
|
underground
power cable systems |
|
. Zhao,
Y.H. Song and Y. Min |
|
Electric
Power Systems Research 53 1 (2000), pp. 23-30 |
|
This
paper presents a new method for detecting and classifying fault transients
in |
|
underground
cable systems based on the use of discrete wavelet transform. A 400 kV |
|
underground
cable system is simulated by ATP/EMTP (electro-magnetic transients |
|
program)
under various system and fault conditions. Daubechies eight wavelet
transform |
|
is
employed to analyze fault transients for the development of a novel fault
detection and |
|
classification
scheme. Simulation results show that this scheme is effective and robust.
|
|
Wavelet
transform based accurate fault location and protection technique for |
|
Chen,
Z.; Bo, Z.Q.; Jiang, F.; Dong, X.Z.; Weller, G.; Chin, N.F. |
|
Advances
in Power System Control, Operation and Management, 2000. APSCOM-00. |
|
2000
International Conference on , Volume: 1 , 2000 |
|
This
paper presents a new fault location tecnique applicable to power cable
circuits. The |
|
proposed
fault locator consists of a transients detection device install yield at
the busbar to |
|
detect
the high frequency voltage transient signals. The initial and subsequent
reflected |
|
travelling
waves cause by the fault are recorded. The wavelet transform (WT) is used
as |
|
a
filter bank to decompose the fault signals. The travelling times of fault
transients and |
|
consequently
the location of the faults are calculated using the extracted signals. The |
|
simulation
studies shown that the WT is effective to extract the transients component |
|
from
the complicate fault signals.
|
|
A
new approach to high-speed protection for transmission line based on |
|
transient
signal analysis using wavelets |
|
Shang,
L.; Herold, G.; Jaeger, J. |
|
Developments
in Power System Protection, 2001, Seventh International Conference on |
|
This
paper describes new criterions for high-speed transmission line protection
using the |
|
wavelet
technique. Based on the representation of the travelling waves through
wavelet |
|
modulus
maxima, the identification criteria for similar transients, such as switch
onto |
|
unloaded
lines and onto faulted lines, are proposed. Simulations are carried out
for testing |
|
the
criteria and the influences of fault location and noise are discussed.
|
|
A
new principle of fault line selection for distribution |
|
Su
Qianli; Dong Xinzhou; Shi Shenxing; Su Bin; He Jiali |
|
Developments
in Power System Protection, 2001, Seventh International Conference on |
|
Fault
line selection is important to maintenance and normal operation of power
distribution |
|
system.
If a fault does not disappear for a long time, it could develop into a
phase to |
|
phase
fault. Then the fault line should be found out as quickly as possible and
the fault |
|
should
be removed. Thus, to select a good method of fault line selection is
necessary. A |
|
transient
signal may be a selection for fault line selection. A travelling wave is a
transient |
|
signal.
It will be more suitable to analyzing the single phase to ground fault
because the |
|
fault
itself is a transient process. But there are two problems to effect the
use of the |
|
travelling
wave signal: first, it is a high frequency signal, so it is hard to
distinguish from |
|
noise;
and secondly there is lack of a proper method to detect and describe the
travelling |
|
wave
signal. Traditional power signals analysis tools are limited in the
presence of |
|
nonsteady
signals. The travelling wave signal possesses a mutant property. In |
|
mathematics,
it is the function of not only time but also frequency. These problems are |
|
solved
with the wavelet transform. The new principle of fault line selection
based on |
|
travelling
waves and wavelet transform is presented.
|
|
A
new project for motor fault detection and protection |
|
Zhang,
X.H.; Cao, Y.N.; Li, Y.L. |
|
Developments
in Power System Protection, 2001, Seventh International Conference on |
|
This
paper discusses a project that is used for detection and protection of the
electrical |
|
and
mechanical faults of motors. Through extracting the characteristics of
sequence |
|
currents
under all kinds of the electrical faults, the authors proposed a simple
and |
|
comprehensive
protective scheme in protection units. At the same time, by analyzing the |
|
spectrum
of the stator currents with wavelet transforms, one can detect the
mechanical |
|
faults
of motors, such as broken rotor bars, etc.
|
|
A
new technique for power transformer protection using discrete dyadic
wavelet |
|
Zhonghao
Yang; Liu, J.Z.; Dong Xinzhou; Jiang, F.; Bo, Z.Q.; Chin, N.F. |
|
Developments
in Power System Protection, 2001, Seventh International Conference on |
|
As one
of the most important elements in modern power system, the transformer is |
|
responsible
for the successful power transmission and distribution. Any unscheduled |
|
repair
work, especially replacement of a faulty transformer, is very expensive
and time |
|
consuming.
Starting from here, this paper discusses an approach to introduce a |
|
wavelet-based
view to identify inrush and other transformer faults. Furthermore, by |
|
careful
cataloging and comparing, the authors found distinct characteristics
corresponding |
|
to
fault and inrush, on the basis of which they proposed a generalized new
criterion for |
|
inrush
identification, that can help to enhance protection reliability. The
outcome of |
|
numerical
simulation shows the effectiveness of the algorithm.
|
|
A
novel approach to the classification of the transient phenomena in power |
|
transformers
using combined wavelet transform and neural network |
|
Mao,
P.L.; Aggarwal, R.K. |
|
Power
Delivery, IEEE Transactions on , Volume: 16 Issue: 4 , Oct 2001 |
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The
wavelet transform is powerful tool in the power transformer transients
phenomena |
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because
to extract information from the transients signal simultaneously in both
the time |
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and
frequency domain. This paper presents a novel technique for accurate
discrimination |
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between
an internal fault and a magnetizing inrush current in the power
transformer by |
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combining
wavelet transform with neural network. The wavelet transform is firstly |
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applied
to the compose the diferenttial current signals of the power transformer
in to a |
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series
of detailed wavelets components. The spectral energies of wavelet
components are |
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calcualted
and then employ to train a neural network to discriminate and internal
fault |
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from
the magnetizing inrush current. The simulate results presented clearly
shown that the |
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proposed
technique can accurately discriminate between and internal fault and a |
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magnetizing
inrush current in power transformer protection.
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Adaptive
reclosure using high frequency fault transients |
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Li
Youyi; Dong Xinzhou; Bo, Z.Q.; Chin, N.F.; Ge Yaozhang |
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Developments
in Power System Protection, 2001, Seventh International Conference on |
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A new
signal processing algorithm for arcing faults detection based on the high
frequency |
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current
transient is presented in this paper. In transient faults, arc current
extinguishes |
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and
then ignites, and this periodically disturbs fault current. After several
cycles, when |
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transient
signals by the fault decay a lot, the arc disturbance can be identified by
the |
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wavelet
transform. The feasibility of this algorithm has been tested by computer |
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Application
of wavelet transform in transient protection-case study: busbar |
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Jiang,
F.; Bo, Z.Q.; Redfern, M.A.; Weller, G.; Chen, Z.; Dong Xinzhou |
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Developments
in Power System Protection, 2001, Seventh International Conference on |
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This
paper presents extensive studies of the application of wavelet transforms
to detecting |
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power
system faults and describes a number of new protection principles and
techniques |
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based
on the wavelet transform. These include a number of novel protection
schemes for |
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the
protection of transmission lines, distribution feeders, generators and
transformers. The |
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significant
advantages of these protection schemes are outlined in the paper. Finally
the |
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application
of the proposed technique to busbar protection is presented to examine the |
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feasibility
of new protective algorithm.
|
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Improved
GPS travelling wave fault locator for power cables by using wavelet |
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W.
Zhao, Y. H. Song and W. R. Chen |
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International
Journal of Electrical Power & Energy Systems, Volume 23, Issue 5, June |
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The
paper proposes an improved approach to cable-fault location, which is
essentially |
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based
on synchronised sampling technique, wavelet analysis and travelling wave
principle. |
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After
an outline of the new scheme and brief introduction to the three major
techniques, |
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wavelet
analysis of faulty transient waveforms is conducted in details to
determine the |
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best
wavelet levels for this particular application. Then a 400 kV underground
cable |
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system
simulated by the Alternative Transient Program (ATP) under various system
and |
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fault
conditions is used to fully evaluate the approach. Numerical results show
that this |
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scheme
is reliable and accurate with errors of less than 2% of the length of the
cable line.
|
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Motor
bearing damage detection via wavelet analysis of the starting current |
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Instrumentation
and Measurement Technology Conference, 2001. IMTC 2001. |
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Proceedings
of the 18th IEEE , Volume: 3 , 2001 |
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Page(s):
1797 -1800 vol.3 |
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Preventive
maintenance of induction motors plays an important role in avoiding
expensive |
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shut-downs
due to motor failures. Motor Current Signature Analysis, MCSA, provides a |
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non-intrusive
way to assess the health of a machine. In this paper, the starting current |
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transient
of an induction motor is analyzed via discrete wavelet transform to detect |
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bearing
faults. The frequency subbands for bearing pre-fault and post-fault
conditions are |
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compared
to identify the effects of bearing/machine resonant frequencies as the
motor |
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Online
rotor bar breakage detection of three phase induction motors by wavelet |
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packet
decomposition and artificial neural network |
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Power
Electronics Specialists Conference, 2001. PESC. 2001 IEEE 32nd Annual , |
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Online
detection algorithm for indcution motor rotor bar breakage is presented
using |
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multi-layer
perception network (MLP) and wavelet packed decomposition (WPD). New |
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features
of rotor bar faults are obtained by wavelet packed decomposition of the
stator |
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current.
These features are of multiple frequency resolutions and obviously
differentiate |
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the
healthy and faulty condition. Features with different frequency resolution
are used |
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together
with the speed slip and the input sets of a 4-layer perceptron network.
The |
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algorith
is evaluated on a small three-phase indcution motor with experiments the |
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laboratory
results show that the proposed method is able to detect the faulty
condition |
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with
high accuracy. This algorithm is also applicable to the detection other
electrical faults |
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Real-time
detection using wavelet transform and neural network of short-circuit |
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faults
within a train in DC transit systems |
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Chang,
C.S.; Kumar, S.; Liu, B.; Khambadkone, A. |
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Electric
Power Applications, IEE Proceedings- , Volume: 148 Issue: 3 , May 2001 |
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A
method is proposed for the real-time detection of DC-link short-circuit
faults in DC |
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transit
systems. The discrete wavelet transform is implemented to detect any
surges in |
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the DC
third-rail current waveform. In the event of a surge the wavelet transform |
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extracts
a feature vector from the current waveform and feeds it to a self-organising |
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neural
network. The neural network determines whether the feature vector belongs
to a |
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normal
or a fault current surge.
|
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Transient
protection of transmission line using wavelet transform |
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Solanki,
M.; Song, Y.H.; Potts, S.; Perks, A. |
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Developments
in Power System Protection, 2001, Seventh International Conference on |
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This
paper presents a new approach to developing protection techniques for EHV |
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overhead
transmission lines. When a fault occurs, the fault current and voltage |
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waveforms
contain significant high frequency transient signals. The presented method
is |
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based
on the detection of fault generated transient signals using wavelet
analysis. The |
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simulation
study is carried out, using ATP-EMTP and wavelet analysis, which indicates |
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that
the proposed approach has the potential of developing high speed
protection relays |
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with
accurate fault detection and classification.
|
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Wavelet
transform in the accurate detection of high impedance arcing faults in |
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high
voltage transmission lines |
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Kim,
C.H.; Kim, H.; Aggarwal, R.K.; Johns, A.T. |
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Developments
in Power System Protection, 2001, Seventh International Conference on |
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(IEE)On
page(s): 422 - 425 |
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This
paper describes a new fault detection technique which involves capturing
the current |
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signals
generated in a transmission line under high impedance faults (HIFs). Its
main |
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thrust
lies in the utilisation of the absolute sum value of signal components
based on the |
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discrete
wavelet transform (DWT). A sophisticated decision logic is also designed
for the |
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determination
of a trip decision. The results presented relate to a typical 154 kV
Korean |
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transmission
system, the faulted signals for which are attained using the well known |
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Electromagnetic
Transients Program (EMTP) software. The simulation also includes an |
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embodiment
of a realistic nonlinear HIF mode |
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