By Topic

Power Delivery, IEEE Transactions on

Issue 2 • Date April 2004

Filter Results

Displaying Results 1 - 25 of 74
  • Table of contents

    Publication Year: 2004 , Page(s): c1 - 450
    Save to Project icon | Request Permissions | PDF file iconPDF (51 KB)  
    Freely Available from IEEE
  • IEEE Transactions on Power Delivery publication information

    Publication Year: 2004 , Page(s): c2
    Save to Project icon | Request Permissions | PDF file iconPDF (37 KB)  
    Freely Available from IEEE
  • Sensor system for monitoring soil moisture content in cable trenches of high-voltage cables

    Publication Year: 2004 , Page(s): 451 - 455
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (160 KB) |  | HTML iconHTML  

    An in-situ moisture sensor intended to measure the moisture content of cable trench filler material is described. The design of the unit, which has been built to integrate with existing data monitoring systems allowing remote interrogation and enabling real-time decisions to be made on circuit loading safety margins, is discussed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • TransientMeter: a distributed measurement system for power quality monitoring

    Publication Year: 2004 , Page(s): 456 - 463
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (488 KB)  

    This paper describes the design and the implementation of TransientMeter, a monitoring system for the detection, classification, and measurement of transient disturbances on electrical power systems. TransientMeter relies on a common object request broker architecture (CORBA) as a communication interface, wavelet-based methods for automatic signal classification and characterization, and on a smart trigger circuit for disturbance detection. The system has been successfully applied to detect, classify, and measure disturbances in an industrial environment. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An improved method for signal processing and compression in power quality evaluation

    Publication Year: 2004 , Page(s): 464 - 471
    Cited by:  Papers (25)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (368 KB) |  | HTML iconHTML  

    This paper introduces a new waveform coding technique, based on wavelet transform, for power quality monitoring purposes. The proposed enhanced data compression method (EDCM) presents a complete adaptive signal processing approach to estimate the fundamental sinusoidal component and separate it from the transient ones in the monitored signal. When these nonstationary components are submitted to the compression technique, the sparse representation property of the wavelet transform provides an improvement in the compression ratio. Also, the degradation inserted by the lossy compression process is minimized. Simulation results confirm the effectiveness of the proposed method when compared to the standard solution, characterized by the compression of the whole monitored signal. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Estimation of frequency and its rate of change for applications in power systems

    Publication Year: 2004 , Page(s): 472 - 480
    Cited by:  Papers (72)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (320 KB) |  | HTML iconHTML  

    A new method for estimation of power frequency and its rate of change is presented. Unlike conventional methods which are based on the concept of linearization, the proposed scheme accommodates the inherent nonlinearity of the frequency estimation problem. This makes the method capable of providing a fast and accurate estimate of the frequency when its deviation from the nominal value is incremental or large. The estimator is based on a newly developed quadrature phase-locked loop concept. The method is highly immune to noise and distortions. The estimator performance is robust with respect to the parameters of its structure. Structural simplicity and performance robustness are other salient features of the method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Robust and frequency-adaptive measurement of peak value

    Publication Year: 2004 , Page(s): 481 - 489
    Cited by:  Papers (19)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (488 KB) |  | HTML iconHTML  

    A new approach for measuring the peak value of the fundamental component of a distorted sinusoidal signal for power system applications is presented. The method is applicable to single-phase as well as three-phase systems. While maintaining structural simplicity, the proposed approach is highly robust with respect to noise and distortion due to disturbances and unbalanced conditions of the system. The method is also highly tolerant of uncertainties in the setting of its internal parameters. The salient feature of the proposed approach is its capability of adapting to the variations in the center frequency of the input signal. The method is suitable for environments that frequency excursions are experienced and conventional discrete Fourier transform (DFT)-based methods do not provide satisfactory results. Speed and accuracy of the response can also be controlled. Structural simplicity and robustness of the proposed scheme make it well suited for digital implementation on software and hardware platforms. Performance of the proposed method is presented based on simulation studies in the MATLAB environment and an experimental setup. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Nonuniform transmission tower model for lightning transient studies

    Publication Year: 2004 , Page(s): 490 - 496
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (336 KB)  

    This paper presents a new approach to model a transmission tower for lightning performance studies. It consists of representing each part of the tower by equivalent vertical and/or horizontal transmission lines as required. While horizontal line parameters are obtained from standard line formulas, specific expressions are derived for the parameters of vertical lines. Moreover, mutual coupling between any two parallel vertical transmission lines is taken into account. Transient waveforms obtained using the proposed method are compared with experimental data obtained using a reduced-scale model and field experiments. The agreement between simulated results and experimental measurements is satisfactory. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A statistical-based sequential method for fast online detection of fault-induced voltage dips

    Publication Year: 2004 , Page(s): 497 - 504
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (480 KB) |  | HTML iconHTML  

    This paper addresses the problem of detecting voltage dips regarding measurements consisting of fault events, transformer saturation events, and capacitor-switching events. A novel statistical-based sequential detection method is proposed for online classification of these events. The detector is based on the Neyman-Pearson criterion that maximizes the detection rate of fault-induced dips with constrained false alarm rate of the other two types of event. The sequential detector is able to give an earliest possible event discrimination together with the estimated confidence at the time instant ranging from 1/8,1/4,1/2, to 3/4 cycle of the fundamental frequency after detecting an initial voltage drop at 0.95 p.u. The performance of the proposed scheme is evaluated using measurements from medium voltage networks. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Performance of demodulation-based frequency measurement algorithms used in typical PMUs

    Publication Year: 2004 , Page(s): 505 - 514
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1032 KB) |  | HTML iconHTML  

    This paper presents a method for evaluating the performance of demodulation-based frequency measurement algorithms in the presence of additive interfering sinusoids. Determination of the performance of amplitude measurement schemes under such conditions is straightforward once the frequency responses of the filters involved in the process are known, since the error induced by a single interfering tone is easily computed using the cascade algorithm's frequency response magnitude. This paper presents a similar method for predicting the worst error of frequency measurement schemes with respect to sinusoidal interference. Once acquainted with the proposed error prediction formula, the only difficulty in designing effective frequency measurement algorithms is the appropriate selection of output filters to achieve the specified performance. The method has been used successfully in designing frequency measurement algorithms currently used in Hydro-Que´bec's special protection schemes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Transmission line distance protection based on wavelet transform

    Publication Year: 2004 , Page(s): 515 - 523
    Cited by:  Papers (50)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (352 KB)  

    Wavelet transform (WT) has the ability to decompose signals into different frequency bands using multiresolution analysis (MRA). It can be utilized in detecting faults and to estimate the phasors of the voltage and current signals, which are essential for transmission line distance protection. A digital distance-protection scheme for transmission lines based on analyzing the measured voltage and current signals at the relay location using WT with MRA is presented in this paper. The scheme has been tested by both computer simulation and experimentally. The tests presented include solid ground faults, phase faults, high impedance and nonlinear ground faults, and line charging. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An intelligent and efficient fault location and diagnosis scheme for radial distribution systems

    Publication Year: 2004 , Page(s): 524 - 532
    Cited by:  Papers (61)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (680 KB) |  | HTML iconHTML  

    In this paper, an effective fault location algorithm and intelligent fault diagnosis scheme are proposed. The proposed scheme first identifies fault locations using an iterative estimation of load and fault current at each line section. Then an actual location is identified, applying the current pattern matching rules. If necessary, comparison of the interrupted load with the actual load follows and generates the final diagnosis decision. Effect of load uncertainty and fault resistance has been carefully investigated through simulation results that turns out to be very satisfactory. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Decision tree-based methodology for high impedance fault detection

    Publication Year: 2004 , Page(s): 533 - 536
    Cited by:  Papers (52)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (112 KB) |  | HTML iconHTML  

    This paper presents a high impedance fault (HIF) detection method based on decision trees (DTs). The features of HIF, which are the inputs of DTs, are those well-known ones, including current [in root mean square (rms)], magnitudes of the second, third, and fifth harmonics, and the phase of the third harmonics. The only measurements needed in the proposed method are the current signals sampled at 1920 Hz. It will reduce the cost of hardware compared with methods that use high sampling rates. A new HIF model is also used. The data of current signals are from the simulation of Electromagnetic Transients Program (EMTP). The DT algorithm trained can successfully distinguish the HIFs from most normal operations on simulation data, including switching loads, switching shunt capacitors, and load transformer inrush currents. Testing on experimental data is recommended for future work. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Alarm processing in electrical power systems through a neuro-fuzzy approach

    Publication Year: 2004 , Page(s): 537 - 544
    Cited by:  Papers (9)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (600 KB) |  | HTML iconHTML  

    This work presents a methodology that combines the use of artificial neural networks and fuzzy logic for alarm processing and identification of faulted components in electrical power systems. Fuzzy relations are established and form a database employed to train artificial neural networks. The artificial neural networks inputs are alarm patterns, while each output neuron is responsible for estimating the degree of membership of a specific system component into the class of faulted components. The proposed method allows good interpretation of the results, even in the presence of difficult corrupted alarm patterns. Tests are performed with a test system and with part of a real Brazilian system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Transmission line distance protection using wavelet transform algorithm

    Publication Year: 2004 , Page(s): 545 - 553
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (344 KB) |  | HTML iconHTML  

    The performance of digital filters for transmission line distance protection significantly influences the effectiveness of the relaying operation. This paper proposes a wavelet-based algorithm, which can be implemented in microprocessor-based protective relays. Simulation results are presented to illustrate the effectiveness of this new algorithm for transmission line distance protection. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Numerical algorithm for adaptive autoreclosure and protection of medium-voltage overhead lines

    Publication Year: 2004 , Page(s): 554 - 559
    Cited by:  Papers (26)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (208 KB) |  | HTML iconHTML  

    In this paper, a new numerical algorithm for medium-voltage overhead lines, autoreclosure, is described. The subfunction of the autoreclosure scheme that would inhibit the first shot after detecting a solid fault (as compared with an arc fault) is evaluated and presented. It is based on one terminal data processing and it is derived in the time domain. In the algorithm the fault nature (arcing or arcless fault) is estimated using linear least error squares estimation technique. The arc, occurring on the fault point during arcing faults on overhead lines, is included in the problem consideration. In addition, by introducing the prefault load current in the existing model, better algorithm performances and a more reliable adaptive algorithm for autoreclosure are achieved. The algorithm is derived for the case of three-phase symmetrical fault. The results of the algorithm testing through computer simulation are presented. Particularly the algorithm sensitivity to arc elongation effects, supplying network parameters, and processing of the signals in the presence of harmonics are tested and analyzed. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Influence of difference system parameters on operating conditions of third harmonic ground-fault protection system of unit-connected generator

    Publication Year: 2004 , Page(s): 560 - 564
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (200 KB) |  | HTML iconHTML  

    In the paper, the influence of unbalance of the measuring element of the unit-connected generator stator ground-fault protection system excited by the ratio of third harmonic voltage to ground in the generator neutral and at the generator terminals on the value of the voltage supplied to the measuring element during ground faults is analyzed. The analysis is made for currently used ground-fault protection systems in which the measuring element is balanced by an autotransformer voltage divider or an impedance bridge. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Optimization of operating conditions of third harmonic ground-fault protection system of generator-transformer unit with two-states transverse parameters

    Publication Year: 2004 , Page(s): 565 - 569
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (168 KB) |  | HTML iconHTML  

    Such an optimization analysis of the operating conditions of the ground-fault protection excited by the third harmonic voltage for the two-state system of the generator-transformer unit transverse parameters is presented in this paper. The analysis was made for a unit in which a change in its transverse branch parameters occurs as a result of generator breaker switching operations. The optimization analysis has shown that effective ground-fault protection of the generator stator windings is possible, regardless of the operating conditions of the generator breaker. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Fault location in transmission lines using one-terminal postfault voltage data

    Publication Year: 2004 , Page(s): 570 - 575
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (408 KB)  

    A new algorithm for fault location in transmission lines, with fault distance calculation based on steady-state measured phasors in local terminal is presented. For the postfault, only voltage phasors are required, avoiding possible errors due to current transformer saturation; the current phasors are required only in prefault time, when saturation does not occur. The algorithm does not use simplifying hypothesis but requires system equivalent data at both line terminals and the fault classification, considering fault resistance purely resistive. In order to verify the algorithm performance, a parametric analysis of variables that influences short-circuit conditions is developed, including an analysis of remote equivalent setting. The results show that the algorithm is very accurate, even in cases when the remote equivalent is not well fitted. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A new concept of voltage-collapse protection based on local phasors

    Publication Year: 2004 , Page(s): 576 - 581
    Cited by:  Papers (39)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (200 KB) |  | HTML iconHTML  

    A new algorithm for protection against voltage collapse is proposed. The algorithm makes use of the magnitudes and angles of the local phasors (i.e., bus voltages and load currents). The change in an apparent power-line flow during a time interval is exploited for computing the voltage-collapse criterion. The criterion is based on the fact that the line losses in the vicinity of the voltage collapse increase faster than the delivery of the apparent power and, at the voltage-collapse point, the losses consume all of the increased power. The selected criterion equals 0 when a voltage collapse occurs. The proposed algorithm could be easily implemented in a numerical relay. The information obtained by the relay can be used at two levels-for the coordinated system-wide control action or for automatic action on the local level. The algorithm is simple and computationally very fast. It was tested on the IEEE 118-bus test system. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Combined fuzzy-logic wavelet-based fault classification technique for power system relaying

    Publication Year: 2004 , Page(s): 582 - 589
    Cited by:  Papers (43)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (728 KB) |  | HTML iconHTML  

    This paper presents a new approach to real-time fault classification in power transmission systems using fuzzy-logic-based multicriteria approach. Only the three line currents are utilized to detect fault types such as LG, LL, and LLG, and then to define the faulty line. An online wavelet-based preprocessor stage is used with data window of ten samples (based on 4.5-kHz sampling rate and 50-Hz power frequency). The multicriteria algorithm is developed based on fuzzy sets for the decision-making part of the scheme. Computer simulation has been conducted using EMTP programs. Results are shown and they indicate that this approach can be used as an effective tool for high-speed digital relaying, as the correct detection is achieved in less than half a cycle and that computational burden is much simpler than the recently postulated fault classification techniques. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Experimental study on the transmission of measurements by tolerance in SCADA systems

    Publication Year: 2004 , Page(s): 590 - 594
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (160 KB) |  | HTML iconHTML  

    The study of the existing relationship between a measurement error and the time elapsed since that measurement was taken in the field, a period of time which we will call the datum age, will allow us to learn about its behavior in a supervisory control and data acquisition (SCADA) system. This study has allowed us to know that, in the case of electrical measurements, they quickly reach their maximum error value because of their age. Therefore, it is not necessary to send measurements to the control center at small intervals: it is possible to wait a given time without having a higher associated error. After getting these results, we have done an experimental study about electrical measurements, in which these measurements are sent to the control center only if they exceed a given percentage of the former measurement, what we call measurement tolerance. In this paper, it has been experimentally proved that this send-by-tolerance method significantly reduces the transmission channel load, so the system can benefit from this because the bandwidth can be reused by more remote units, as well as performance of the existing ones is improved. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Method for calculating the ground resistance of grounding grids using FEM

    Publication Year: 2004 , Page(s): 595 - 600
    Cited by:  Papers (16)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (280 KB) |  | HTML iconHTML  

    Taking as given that ground resistance is independent of earth fault current, this paper presents a new way of calculating ground resistance of grounding grids using the finite-element method (FEM). Ground resistance is calculated by means of three consecutive tests, with an acceptable number of elements, and fast resolution. The results of the proposed method are compared with those measured experimentally or determined by other authors. Once ground resistance and earth fault current are known, grid potential and touch-and-step voltages are calculated. The main advantage of the method proposed here is that it permits us to analyze symmetrical and nonsymmetrical grids of any shape in uniform, two-layer, and multilayer soils. The method developed in this paper constitutes a fast-resolution industrial application, with acceptable results, for calculating the ground resistance of grounding grids of any shape. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A new artificial treatment for the reduction of resistance in ground electrode

    Publication Year: 2004 , Page(s): 601 - 608
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (704 KB) |  | HTML iconHTML  

    This study describes a resistance reduction additive (RRA) for reducing and maintaining reduced resistance of ground electrodes over time. The RRA employed was a mixture of inorganic salts, some of which occur as residues from industrial mineral processing in Chile. Chemical characteristics of the mixture are described, as well as results of measurements of electrical resistance of ground electrodes over time with and without RRA treatment. Measures are also given for current intensities and loss of electrode mass in test electrodes buried below ground with RRA and within cell containers having a specific capacity. Small scale tests were made on the effects of impulse current in test cells containing electrodes treated with the RRA. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Condition assessment of contacts in gas-insulated substations

    Publication Year: 2004 , Page(s): 609 - 617
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (216 KB) |  | HTML iconHTML  

    A new method for assessing the condition of electric contacts and joints inside gas-insulated substations (GISs) that overcomes the limitations of conventional diagnostic methods is proposed. The contact resistance in degraded or overstressed electrical contacts varies slightly when currents of different amplitudes are passed. The diagnostic method is based on detecting this nonlinear behavior. For testing of the contacts in large GIS, excitation currents up to several thousand amperes are required. By using a capacitor-based current supply, such currents can be achieved with a portable source. The testing can be carried out without dismantling the GIS. No earlier measurements or manufacturer specifications are required. In full-scale testing under realistic operating conditions on 145-420 kV GIS using prototype instrumentation a very good sensitivity for detecting contact degradation in an early stage was obtained. View full abstract»

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

Aims & Scope

Installation and operation of apparatus, equipment, structures, materials and systems for the safe, reliable and economic generation, transmission, distribution, conversion, measurement and control of electric energy.

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Wilsun Xu
Ph.D., P.Eng.
Dept. Electrical and Computer Eng.
University of Alberta
(9107 - 116 Street)
Edmonton, Alberta T6G 2V4 Canada
wxu@ualberta.ca
Phone:780-492-5965
Fax:780-492-1811