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Power Delivery, IEEE Transactions on

Issue 3 • Date July 2009

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Displaying Results 1 - 25 of 98
  • Table of contents

    Publication Year: 2009 , Page(s): C1 - 979
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    Freely Available from IEEE
  • IEEE Transactions on Power Delivery publication information

    Publication Year: 2009 , Page(s): C2
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    Freely Available from IEEE
  • Theoretical Maximum Limits on Power-Handling Capacity of HVDC Cables

    Publication Year: 2009 , Page(s): 980 - 987
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (498 KB) |  | HTML iconHTML  

    In the case of an ac cable, power transmission is limited by the length of the cable due to the capacitive reactive current component. It is well known that high-voltage direct current (HVDC) cables do not have such limitations. However, insulation-related thermal problems pose a limitation on the power capability of HVDC cables. The author presents a viable theoretical development, a logical extension to Whitehead's theory on thermal limitations of the insulation. The computation of the maximum power-carrying capability of HVDC cables subject to limits on the maximum operable temperature of the insulation is presented. The limitation on the power-carrying capability is closely associated with the electrothermal insulation failure. The effect of environmental interaction by way of external thermal resistance, an important aspect, is also considered in the formulations. The Lagrange multiplier method has been used to handle the ensuing optimization problem. The theory is based on an accepted theory of thermal breakdown in insulation and is an important and a coherent extension of great significance. View full abstract»

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  • Micromachined Electric-Field Sensor to Measure AC and DC Fields in Power Systems

    Publication Year: 2009 , Page(s): 988 - 995
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2328 KB) |  | HTML iconHTML  

    This paper describes a new type of electric-field sensor that has been fabricated using micromachining technology. This micromachined sensor is dramatically smaller than conventional field mills, possessing a field chopping shutter measuring only 1 mm2 . The shutter is moved using thermal actuators, thereby eliminating the wear and tear associated with rotating and moving elements of field mills. The sensor requires minimal operating power, with the shutter being driven by a 75-mV drive signal while consuming only 70 muW. The field chopping shutter operates at ~ 4200 Hz, enabling the measurement of both ac and dc fields. Two sets of sense electrodes enable differential field measurements and, therefore, do not require a reference ground potential. The sensor has a linear response to the electric-field amplitude and has demonstrated that it is capable of measuring a dc field as small as 42 V/m. This miniature sensor is the smallest sensor with such a resolution for use in power engineering applications. View full abstract»

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  • Apparatus for Online Power Transformer Winding Monitoring Using Bushing Tap Injection

    Publication Year: 2009 , Page(s): 996 - 1003
    Cited by:  Papers (13)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1055 KB) |  | HTML iconHTML  

    Online transformer condition monitoring techniques based on transfer function methods, such as transmission-line diagnostics and swept frequency-response analysis, require the injection of a known test signal into the transformer. On larger power transformers, a practical method is to use the available bushing tap connection. In this paper, we will discuss a custom high-power signal generator that injects high-frequency signals on the bushing tap of the transformer under investigation, as well as a circuit to replace the bushing tap short and allow online operation of the system. Finally, the system is demonstrated on a 650 kV transformer. View full abstract»

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  • Improvement of Accuracy of Power System Spectral Analysis by Coherent Resampling

    Publication Year: 2009 , Page(s): 1004 - 1013
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (857 KB) |  | HTML iconHTML  

    The coherent resampling (CR) algorithm, which improves the accuracy of discrete Fourier transform (DFT)-based power system frequency analysis, is described in the paper. The algorithm uses extended Kalman filter for instantaneous frequency tracking and fractional B-spline resampler for signal approximation. The CR algorithm is a software counterpart of synchronous sampling, i.e., sampling, synchronized with fundamental frequency of the signal. CR may either be applied to previously noncoherently sampled signals or to work in realtime. Frequency estimation, amplitude spectrum estimation and THD factor estimation results obtained by presented algorithm are compared to those obtained by other methods. Both simulated and real signals were used for tests. Brief summary of realtime DSP implementation of CR algorithm is also given. View full abstract»

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  • Optimal Placement of Phasor Measurement Units Using Immunity Genetic Algorithm

    Publication Year: 2009 , Page(s): 1014 - 1020
    Cited by:  Papers (51)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (467 KB) |  | HTML iconHTML  

    This paper investigates the application of immunity genetic algorithm (IGA) for the problem of optimal placement of phasor measurement units (PMUs) in an electric power network. The problem is to determine the placement sites of the minimal set of PMUs which makes the system observable. Incorporating immune operator in the canonical genetic algorithm (GA), on the condition of preserving GA's advantages, utilizes some characteristics and knowledge of the problems for restraining the degenerative phenomena during evolution, so as to improve the algorithm efficiency. This type of prior knowledge about some parts of optimal solution exists in the PMU placement problem. So, the IGA is adopted in this paper to solve the problem. Also, a new effect which is preventing from familial reproduction is studied which shows an increase in converging speed. The effectiveness of the proposed method is verified via IEEE standard systems and a realistic large-scale power system. View full abstract»

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  • Real-Time Estimation of Power System Frequency Using Nonlinear Least Squares

    Publication Year: 2009 , Page(s): 1021 - 1028
    Cited by:  Papers (24)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1072 KB) |  | HTML iconHTML  

    This paper presents a nonlinear least squares method for measuring the power system frequency, wherein the voltage at the measurement point is modeled by using the Fourier series. The estimation of the fundamental frequency is a nonlinear problem in this formulation and is solved by performing a 1-D search over the range of allowed frequency variation. The voltage signal is used for frequency estimation because it is typically less distorted than the line current, resulting in computational efficiency. The robustness of this algorithm with respect to change in various parameters is studied through simulation and the results are validated by hardware implementation using a Virtex IV field-programmable gate array. An application of this algorithm to a shunt active power filter is also presented. View full abstract»

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  • Assessment of the Impact of Joint Bays on the Ampacity of High-Voltage Cable Circuits

    Publication Year: 2009 , Page(s): 1029 - 1036
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (674 KB) |  | HTML iconHTML  

    Improvements in the cost and availability of computational power in recent years has led to numerical techniques such as finite-element analysis (FEA) becoming viable for cable-rating calculations. This analysis has previously been completed for the case of directly buried and force-cooled cable circuits, but without direct consideration of the joint bay. This paper presents methods by which conductor temperature profiles within joint bays may be obtained through the use of FEA. Results are presented for a number of joint bay configurations common to the U.K. for naturally and force-cooled installations. Implications of the results on circuit-rating practice are discussed and the benefits of using tools, such as FEA, are considered versus other existing methods. View full abstract»

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  • Fast and Reliable CT Saturation Detection Using a Combined Method

    Publication Year: 2009 , Page(s): 1037 - 1044
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (761 KB) |  | HTML iconHTML  

    Busbar differential relays may operate incorrectly for external faults due to current-transformer (CT) saturation. In this paper, two different techniques are suggested to detect CT saturation. The first proposed technique is based on the fact that the waveshape of the CT secondary current changes significantly at the instant of the saturation. Based on this feature, an algorithm which uses the second derivative of CT output current is developed. It uses an adaptive threshold to detect CT saturation fast. The second proposed technique utilizes two criteria based on the zero crossing principle. Utilizing the combination of the second derivative and zero crossing techniques results in a powerful and reliable scheme which is able to detect various CT saturation cases correctly and quite fast. The proposed method is able to detect even small CT saturation events. A real 400-kV busbar is simulated using PSCAD/EMTDC for evaluating the performance of the proposed algorithm. The obtained results demonstrate precise operation of the proposed algorithm in different conditions. View full abstract»

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  • Protection of Low-Voltage DC Microgrids

    Publication Year: 2009 , Page(s): 1045 - 1053
    Cited by:  Papers (77)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1022 KB) |  | HTML iconHTML  

    In this paper, a low-voltage (LV) DC microgrid protection system design is proposed. The LV DC microgrid is used to interconnect distributed resources and sensitive electronic loads. When designing an LV DC microgrid protection system, knowledge from existing DC power systems can be used. However, in most cases, these systems use grid-connected rectifiers with current-limiting capability during DC faults. In contrast, an LV DC microgrid must be connected to an AC grid through converters with bidirectional power flow and, therefore, a different protection-system design is needed. In this paper, the operating principles and technical data of LV DC protection devices, both available and in the research stage, are presented. Furthermore, different fault-detection and grounding methods are discussed. The influence of the selected protection devices and grounding method on an LV DC microgrid is studied through simulations. The results show that it is possible to use available devices to protect such a system. Problems may arise with high-impedance ground faults which can be difficult to detect. View full abstract»

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  • Design of a New Transformer-Isolated Analog Acquisition System

    Publication Year: 2009 , Page(s): 1054 - 1062
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (777 KB) |  | HTML iconHTML  

    A new transformer-isolated analog acquisition system that is described in this paper greatly reduces the size, weight, and cost of the isolation transformer. This paper also develops the concept of pulsing the isolated analog signal only for the portion of time needed for analog-to-digital conversion. An operational amplifier with a feedback winding from the isolation transformer achieves high accuracy for the isolated analog signal. Other topics in this paper include the additional use of the isolation transformer for an isolated switched-mode power supply and the implementation of the isolation transformer through the use of a small E-E ferrite core and printed-circuit windings. View full abstract»

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  • Field-Programmable Analog Array Based Distance Relay

    Publication Year: 2009 , Page(s): 1063 - 1071
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (431 KB) |  | HTML iconHTML  

    Protective relays have been designed with different technologies resulting in electromechanical, solid-state, and numerical devices. Speed and reliability are the two most important characteristics of a protective relay. Other capabilities such as monitoring and recording are supposed to be of secondary priority. Without any doubt, present-day numerical relays provide considerable capabilities and advantages but they have not improved speed of operation in comparison to their solid-state counterparts. With advancements in analog technology which has become more mature recently, the idea of using mixed signals in several applications has started. The new technology using combination of field-programmable analog arrays (FPAAs) and digital technologies seems to be a breakthrough and has the potential to provide better performance than the present-day numerical relays. In this paper, use of FPAAs for designing and implementing protective relays is investigated for the first time in literature. A distance relay design and its hardware implementation using FPAAs is described. Test results are reported. View full abstract»

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  • Residual Compensation for Ground Impedance Relay With Applications in UHV Transmission Lines

    Publication Year: 2009 , Page(s): 1072 - 1078
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (286 KB) |  | HTML iconHTML  

    The impedance algorithm in distance protection for high voltage (HV) and extra high voltage (EHV) lines, although neglecting the influence of shunt capacitance, is able to produce satisfactory performance. However, the accuracy of the algorithm is significantly reduced when applying to ultra high voltage (UHV) lines due to the larger P.U. line shunt capacitance and longer transmission radius. Therefore, the distributed parameter model should be adopted, and the relay should be set based on the hyperbola function between measuring impedance and the fault distance. However, how to define and set the indexes in relay ever defined with lumped parameters, such as the residual compensation coefficient, is still unresolved. In response to this question, the paper models the UHV system with distributed parameters and introduces the concept of virtual equivalent line length controlled by zero sequence system impedance, and then proposes a novel residual compensation coefficient. Case studies and RTDS tests show that the relay with proposed coefficient offers good performance for the simulated cases. The results also can be extended into other applications, such as the design of zero sequence reactance relay, fault location, fault phase selection, power swing blocking, and load blocking components. View full abstract»

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  • Identification of Cross-Country Fault of Power Transformer for Fast Unblocking of Differential Protection

    Publication Year: 2009 , Page(s): 1079 - 1086
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (464 KB) |  | HTML iconHTML  

    Due to the different ratings of the current transformers (CT) located on different sides of power transformer, only the CT of low ratings will saturate when the power transformer experiences a heavy through fault, leading to false differential current. Such type of external fault can be identified from the internal one if the differential protection is equipped with the percentage restraint characteristic together with the method using operation time difference between pickup element and differential protection. However, the differential protection will be wrongly blocked as well if a cross-country fault occurs. According to the investigations in this paper, in the event of an external fault accompanied by the CT saturation, the variation of most samples of the secondary current of the saturated CT is inversely proportional to the variation of the differential current. Comparatively, this law cannot be followed on the occasion of an internal fault. In this case, the locus of the variation of the saturated secondary current with the differential current can be used to dynamically discriminate if an external fault develops to an internal fault. With the method proposed in this paper, the ability of the differential protection immune to cross-country fault can be improved further. The effectiveness of the proposed method is verified with the simulation tests. View full abstract»

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  • Laboratory Investigation of Using Wi-Fi Protocol for Transmission Line Differential Protection

    Publication Year: 2009 , Page(s): 1087 - 1094
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1103 KB) |  | HTML iconHTML  

    Pilot wire differential protection is one of the most common methods for protecting short transmission lines. The conventional protection scheme has drawbacks, such as malfunction due to line disconnection and limited line length. A laboratory investigation of transmission line protection using Wireless Fidelity (Wi-Fi) communication protocol for data sharing between the relays located at the two ends of the transmission line is presented in this paper. The protection algorithm is based on current signals measured at both ends of the transmission line. The data is exchanged through the wireless communication network. The relay decision is based on data sharing obtained through wireless communication network. The suggested technique satisfies high degree of reliability and stability. View full abstract»

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  • Lightning Currents Flowing in the Soil and Entering a Test Power Distribution Line Via Its Grounding

    Publication Year: 2009 , Page(s): 1095 - 1103
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1644 KB) |  | HTML iconHTML  

    Current from nearby rocket-triggered lightning that flowed through the soil and into an unenergized test power distribution line was studied based on experimental data acquired in 2003 at the International Center for Lightning Research and Testing in Florida. The 15-pole, three-phase line was 812 m long, was equipped with four arrester stations, at poles 2, 6, 10, and 14, and was terminated in its characteristic impedance at poles 1 and 15. The neutral conductor of the line was grounded at each arrester station and at both line terminations. Measurements suggest that a significant fraction of the lightning current injected into the earth a distance of 11 m from pole 15 entered the line through the grounding system of pole 15. The peak value of the microsecond-scale return stroke current entering the line through the pole 15 line ground was 7% of the peak value of the return stroke current injected into the earth. The peak value of the millisecond-scale triggered lightning initial stage current and the millisecond-scale return-stroke and initial-stage charge transfer to the line through the pole 15 line ground was between 12% and 19% of the lightning peak current/charge transfer, indicating that the percentage values for the injected peak currents are dependent on the current waveshape: for microsecond-scale return stroke currents, possibly due to electromagnetic coupling effects, a smaller fraction of the current peak enters the line compared to millisecond-scale initial stage currents. In the latter case, any influence of electromagnetic coupling to the line on ground currents is expected to be negligible. View full abstract»

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  • Fourier Transform-Based Modified Phasor Estimation Method Immune to the Effect of the DC Offsets

    Publication Year: 2009 , Page(s): 1104 - 1111
    Cited by:  Papers (28)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (755 KB) |  | HTML iconHTML  

    This paper proposes a Fourier transform-based modified phasor estimation method to eliminate the adverse influence of the exponentially decaying dc offsets when discrete Fourier transform (DFT) is used to calculate the phasor of the fundamental frequency component in a relaying signal. By subtracting the result of odd-sample-set DFT from the result of even-sample-set DFT, the information of dc offsets can be obtained. Two dc offsets in a secondary relaying signal are treated as one dc offset which is piecewise approximated in one cycle data window. The effect of the dc offsets can be eliminated by the approximated dc offset. The performance of the proposed algorithm is evaluated by using computer-simulated signals and Electromagnetic Transients Program-generated signals. The algorithm is also tested on a hardware board with TMS320C32 microprocessor. The evaluation results indicate that the proposed algorithm can estimate the accurate phasor of the fundamental frequency component regardless of not only the primary decaying dc offset but also the secondary decaying dc offset caused by CT circuit itself including its burden. View full abstract»

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  • High-Voltage Multicarrier Spread-Spectrum System Field Test

    Publication Year: 2009 , Page(s): 1112 - 1121
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1033 KB) |  | HTML iconHTML  

    High-voltage (HV) power lines have been used as a communications medium since the 1920s. Those point-to-point links were typically based on single-sideband amplitude modulation. These days, the state of the art in HV power-line carrier (PLC) communications comprises the combination of analog systems, mainly for teleprotection tasks, and digital systems, used for voice and data transmission. Beside traditional core services (monitoring, operation management, and limitation and removal of failures), electrical utilities would like to satisfy the increasing need of new internal applications. In that way, quadrature amplitude modulation and, most recently, multicarrier modulation (MCM)-based modems are beginning to play an important role in HV PLC systems. Although the typical 4-kHz bandwidth has been recently increased up to 32 kHz, this paper proposes a low-power 256-kHz bandwidth multicarrier-spread-spectrum (MC-SS)-based physical layer. Based on channel measurements, the MC-SS symbol has been designed and tested in order to increase the user bit rate while delivering reduced power spectral density and bit-error rate. View full abstract»

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  • Scattering Parameters-Based Channel Characterization and Modeling for Underground Medium-Voltage Power-Line Communications

    Publication Year: 2009 , Page(s): 1122 - 1131
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1340 KB) |  | HTML iconHTML  

    Power-line communications (PLC) technologies rely on the power grid for data transmission. Since the communications channel is already deployed, this communication alternative is specially interesting for the power grid owner (i.e., the electrical utility). The medium-voltage (MV) distribution network, located after the last step-down electrical substation with typical levels from 6 to 25 kV, directly feeds large consumers and small ones through several transform stations. The growing interest on MV-PLC technology, the natural aggregation point for data coming and going into the low-voltage (LV) network, faces the same issue that the LV-PLC technology did (and does): standardization. In this way, a properly implemented channel model will allow the design of suitable modulation and access methods. This paper proposes a deterministic channel model for the MV underground network transfer function, based on a complete set of measurements performed in an MV urban ring. Moreover, the characterization of the MV-PLC channel elements as well as the noise scenario and access impedance have been carried out. View full abstract»

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  • The Application-View Model of the International Standard IEC 61850

    Publication Year: 2009 , Page(s): 1132 - 1139
    Cited by:  Papers (15)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (667 KB) |  | HTML iconHTML  

    The introduction of IEC 61850 as the de facto SA standard for the communication between devices in a substation and the related system requirements has made it possible and justifiable to integrate station Intelligent Electronic Devices (IEDs) on a high-speed peer-to-peer communication network (Ethernet) through standardization. IEC 61850 presents a set of standard object-oriented (OO) data models to describe the processes to be implemented and controlled in a substation and a set of service models for the interactions between devices in a substation and the transfer of all sorts of IED data. IEC 61850 proposes the concept of standardizing IED data using data objects referred to as logical nodes. This makes it possible to achieve the ldquoplug and playrdquo capability so that information and commands can be shared on a single network independent from any implementation. In this paper, the authors describe the standard's application-view model and present the use of OO methodology and techniques for the implementation of the Logical Node (LN) application-view data model of the standard. The target audience for this paper includes power system protection and automation engineers and technicians as well as research personnel who have at least a basic understanding of the IEC 61850 international standard and other technology mechanisms addressed in this paper. View full abstract»

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  • Object Modeling of Data and DataSets in the International Standard IEC 61850

    Publication Year: 2009 , Page(s): 1140 - 1147
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (984 KB) |  | HTML iconHTML  

    In the past decade, new communication schemes have been designed and retrofitted into substations by utilities to integrate data from relays and intelligent electronic devices (IEDs). The idea of standardizing the language of communication between IEDs has evolved as the key for the advancement of connectivity and interoperability within a SA system. The most important outcome of this standardization process has been the IEC 61850 standard. IEC 61850 is an abstract application layer protocol aimed at providing interoperability between a variety of substation and feeder devices by describing how devices are to communicate in a substation as well as the related system requirements. In this paper, the authors describe the standard's application-view model and present the use of OO methodology and techniques for the modelling and implementation of the data and dataset application-view object models of the standard. The target audience for this paper includes anyone interested in getting an overview of the IEC 61850 international standard, and understanding how the object-oriented models proposed in the standard standardize the data found in IEDs and the communication of this date between substation devices. View full abstract»

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  • Open-Source Implementation of Monitoring and Controlling Services for EMS/SCADA Systems by Means of Web Services— IEC 61850 and IEC 61970 Standards

    Publication Year: 2009 , Page(s): 1148 - 1153
    Cited by:  Papers (14)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (909 KB) |  | HTML iconHTML  

    This paper presents an implementation of monitoring and controlling services for energy-management system/supervisory-control-and-data-acquisition systems, based on IEC 61970 and IEC 61850 international standards. The proposed solution is based on Web services technology that enables the typical advantages of an open-source framework, such as applications decoupling, applications integration, reduction of upgrading costs, reuse of existing infrastructures, and ease of development. Standardized interfaces are provided by the generic interface definition interfaces of IEC 61970. The Web server that has been developed has been tested in a simulation environment where the physical devices of a generic power system were simulated with databases whose data models were provided by the common information model of IEC 61970. View full abstract»

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  • Advanced Key-Management Architecture for Secure SCADA Communications

    Publication Year: 2009 , Page(s): 1154 - 1163
    Cited by:  Papers (18)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (766 KB) |  | HTML iconHTML  

    Supervisory control and data-acquisition (SCADA) systems are control systems for many national infrastructures. In the past, SCADA systems were designed without security functionality because of the closed operating environment. However, the security of SCADA systems has become an issue with connection to open networks becoming more common. Any damage to the SCADA system can have a widespread negative effect to society. In this paper, we review constraints and security requirements for SCADA systems and then investigate whether the existing key-management protocols for the SCADA systems satisfy these requirements. Afterward, we propose an advanced key-management architecture fitted for secure SCADA communications. The contributions of our work are two-fold. First, our scheme supports both message broadcasting and secure communication. Second, by evenly spreading much of the total amount of computation across high power nodes (MTU or SUB-MTU), our protocol avoids any potential performance bottleneck of the system while keeping the burden on low power nodes (RTU) at minimal. View full abstract»

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  • Transmission Characteristics of Overhead Medium-Voltage Power-Line Communication Channels

    Publication Year: 2009 , Page(s): 1164 - 1173
    Cited by:  Papers (22)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (578 KB) |  | HTML iconHTML  

    This paper considers broadband signal transmission via three-phase overhead medium-voltage (MV) lines above the lossy plane ground. The established methods dealing with transmission along MV power lines are examined in terms of the end-to-end transfer function under various network configurations. The MV broadband over the power-lines transmission channel is investigated with regard to its spectral behavior, the usable bandwidth, and the end-to-end signal attenuation. It is found that the aforementioned features depend drastically on the number and type of branches existing along the end-to-end broadband over power-lines signal propagation. View full abstract»

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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