Search

The traction transformer of a high-speed railway is long-term subjected to the effects of impulse traction loads, such that the aging status of a multilayer insulation paper between high and low voltage windings is non-uniformly distributed due to the non?uniform distribution of temperature. To enhance the use of the frequency domain dielectric spectroscopy (FDS) method in engineering, this paper studies the effects of non-uniform thermal aging on the frequency domain dielectric spectrum of multilayer insulation paper. Based on the experimental designs and preparation of experimental materials, the frequency domain dielectric spectrum of a multilayer insulation paper with uniform and non-uniform thermal aging distribution was tested. Afterwards, the effects of non-uniform thermal aging on the frequency domain dielectric spectrum of multilayer insulation paper were discussed and analyzed based on the tested results. The results show that: 1) The effects of the non-uniform distribution of DP (cellulose structure) can be ignored. The non-uniform distribution of the aging byproducts (except moisture) has limited effects on the tested results, which is far less than the effects of moisture. The non-uniform distribution of moisture is the dominant factor and affects the results. 2) In terms of insulation paper with a defined aging status, its order in the multilayer insulation paper does not affect the tested results. 3) The tested results of the insulation samples with a non-uniform aging distribution can no longer reflect the moisture content of the wettest section, and the evaluated moisture content is slightly higher than the average moisture content of the multilayer insulation paper. [ABSTRACT FROM PUBLISHER]

A generalization of the problem of writing on dirty paper is considered in which one transmitter sends a common message to multiple receivers. Each receiver experiences on its link an additive interference (in addition to the additive noise), which is known noncausally to the transmitter but not to any of the receivers. Applications range from wireless multiple-antenna multicasting to robust dirty paper coding. We develop results for memoryless channels in Gaussian and binary special cases. In most cases, we observe that the availability of side information at the transmitter increases capacity relative to systems without such side information, and that the lack of side information at the receivers decreases capacity relative to systems with such side information. For the noiseless binary case, we establish the capacity when there are two receivers. When there are many receivers, we show that the transmitter side information provides a vanishingly small benefit. When the interference is large and independent across the users, we show that time sharing is optimal. For the Gaussian case, we present a coding scheme and establish its optimality in the high signal-to-interference-plus-noise limit when there are two receivers. When the interference power is large and independent across all the receivers, we show that time-sharing is again optimal. Connections to the problem of robust dirty paper coding are also discussed. [ABSTRACT FROM AUTHOR]

Electrical equipment supplying and distributing energy is used in every pulp and paper industrial process. Many components made of various metallic and dielectric materials are vulnerable to corrosive atmospheres often present in the pulp and paper industrial facilities. Corrosion of electrical conductors may result in fast and irreversible deterioration, causing production loss and safety hazards. The paper reviews the most severe corrosion problems effecting conductivity of electrical contacts that result in overheating of electrical equipment used in this industry. A number of various protecting means are suggested to slow down corrosion of silver and copper and other metals most often used in electrical equipment. The paper discusses implementations and the value of various condition-monitoring techniques to provide timely maintenance of electrical equipment exposed to corrosive environments in the pulp and paper facilities. [ABSTRACT FROM AUTHOR]

Main insulation of windings connected with valves in high voltage direct current (HVDC) convert transformers withstands pulsating DC voltages. This paper presents breakdown properties of oil-impregnated paper under pulsating DC voltages at different temperatures. Progressive stress tests were carried out to obtain breakdown voltages of oil-impregnated paper with thickness of 0.2 mm under pulsating DC voltages at different temperatures. Constant stress tests were executed to measure time to breakdown of the oil-paper specimens. Both types of the experiments were also undertaken under either AC or DC voltages. An electrical aging lifetime model was proposed for the oil-impregnated paper, and parameters of the electrical aging lifetime model were presented. Experiments and analysis results show that the breakdown voltages and time to breakdown of oilpaper insulation are influenced by temperature significantly. [ABSTRACT FROM PUBLISHER]

Few studies have been carried out on the failure processes of low voltage distribution cables. This is mainly due to their excellent track record of high reliability, and their use of traditional technologies. Growing quantities of aged cable within the network now make management of these assets an important issue. This paper describes measurements of leakage current, partial discharges and arc formation within 400 V oil-impregnated paper insulated cable structures which have been artificially wetted by immersion in bulk water. A generic picture is produced to show the gradual evolution from a leakage current through discharge growth to final catastrophic failure. Rapid changes to the core temperature of a wet cable are shown to produce transient, high levels of leakage current. It is also shown that by increasing the core temperature more slowly these high levels can be reduced. It is suggested that the characteristics of individual arcs within successive half cycles may provide a basis for predicting whether an incipient fault will lead to failure in the short term. [ABSTRACT FROM AUTHOR]

Knowledge about moisture content in oil impregnated paper insulation is essential when estimating remaining lifetime of power transformers. Direct evaluation of moisture content is rarely possible due to inaccessibility of the internal insulation system in transformers. Therefore, various indirect estimation techniques are utilized. Frequency domain spectroscopy (FDS) measurements of transformer insulation belong to this group. To perform high quality interpretation of results of FDS measurements a good knowledge on dielectric responses in oil impregnated pressboard and paper is required, especially as it refers to their variation with water content and temperature. The aim of this paper is to provide an open access to the frequency domain spectra of oil impregnated paper and pressboard samples, which can then be used in modeling of the results of diagnostic measurements in power transformers. [ABSTRACT FROM AUTHOR]

This paper discusses a practical approach to allow personnel safe access to switchgear while maintaining pulp and paper mill processes, specifically in existing electrical distribution system unit substation installations where a main breaker was not incorporated into the original design. Various component configurations were evaluated prior to a final solution being implemented. Modernization of existing equipment was determined to be the most efficient and cost-effective solution, allowing mill personnel to work safely on switchgear during periods of mill production. [ABSTRACT FROM AUTHOR]

An extensive revision of the IEEE C37.011 ‘Application Guide for TRV for AC High-Voltage circuit Breakers’ has been in process for the last four years. The main aim was to introduce the two- and the four- parameter description of the transient recovery voltage (TRV) as used in IEC Switchgear standards that have been introduced in the revisions of Standards C37.04 and C37.06. These two standards are being concurrently revised, but IEEE C37.011 provides the necessary explanations on TRV characteristic in advance. Non-specialist engineer users of the guide will better understand these standards. [ABSTRACT FROM AUTHOR]

The article presents the winners in the Harold A. Wheeler Applications Prize Paper Award for 2017. It highlight the significance of the award which recognizes authors of the best applications paper published in the Institute of Electrical and Electronics Engineers (IEEE) Transactions on Antennas and Propagation. The winners include Dia'aaldin J. Bisharat, Shaowei Liao and Quan Xue.

Acid catalyzed ageing of oil impregnated kraft paper has been studied experimentally. Five different carboxylic acids (formic, acetic, laevulinic, stearic and naphtenic acid) have been added to mineral oil to arrive at a neutralization value of 0,4 mg KOH/g. Thereafter, kraft paper of two different humidities has been allowed to equilibrate with the oil. The results show that the lower the molecular weight of the carboxylic acids is the more is absorbed by the paper. Furthermore, a clear synergy for the paper ageing rates between moisture and the lower molecular weight acids is found, while for the higher molecular weight acids almost no effects were found. It is concluded that present techniques for measuring acidity of oils do not reflect these detailed conditions. It is suggested to introduce a new measuring technique for neutralization value where water rinsing is used to identify the content of low molecular weight, water soluble acids. [ABSTRACT FROM AUTHOR]

Prospective authors are requested to submit new, unpublished manuscripts for inclusion in the upcoming event described in this call for papers. [ABSTRACT FROM AUTHOR]

Presents the recipients of the Piergiorgio L. E. Uslenghi Letters Prize Paper Award. [ABSTRACT FROM PUBLISHER]

Describes the above-named upcoming special issue or section. May include topics to be covered or calls for papers. [ABSTRACT FROM AUTHOR]

The IEEE International Conference on Plasma Science (ICOPS) is an annual meeting of the plasma physics community known for the broad range of topics addressed as well as for its varied international locations. The 42nd ICOPS was held in Belek, Antalya, Turkey, on May 24–28, 2015. It was the first time that ICOPS was held in Turkey and the region. The General Chair of ICOPS 2015 was Prof. Lütfi Öksüz from Suleyman Demirel University (Isparta, Turkey), the Technical Program Chair was Dr. Christine Coverdale from Sandia National Laboratories (Albuquerque, NM, USA), and the conference Liaison was Prof. Edl Schamiloglu from the University of New Mexico (Albuquerque, NM, USA). As is traditional, the conference consists of all plasma science topics including 7 technical sessions and 35 subsessions. There were almost 400 registrants at ICOPS 2015, and over 500 abstracts are included in the conference. This ICOPS 2015 meeting especially attracted attendance from the Middle East, China, and Russia. [ABSTRACT FROM PUBLISHER]

The article presents the cross-sectional results of analyzes of authentic conducted disturbances introduced into public power networks by various types of loads installed at end users. The foundation for the research was a set of 260 identified cases of Power Line Communication (PLC) transmission disturbances based on the Open Smart Grid Protocol (OSGP) technology, which were recorded in the urban network of the distribution system operator covering over 400,000 smart meters. The paper presents a quantitative assessment of the share of loads that most often cause problems with transmission efficiency. Moreover, a qualitative assessment of the detected disturbance cases was carried out in terms of conditions relating to the structure of the power grid and real transmission levels and disturbance levels. The authors made a pioneering analysis in the so-called “communication path” where the PLC communication disturbance was identified, i.e., from the installation point of the PLC concentrator to the metering point where the energy meter, with which the connection was lost, was installed. [ABSTRACT FROM AUTHOR]

Describes the above-named upcoming special issue or section. May include topics to be covered or calls for papers. [ABSTRACT FROM AUTHOR]

These instructions give guidelines for preparing papers for the IEEE TRANSACTIONS ON CONSUMER ELECTRONICS. The downloaded template must be used. [ABSTRACT FROM PUBLISHER]

Reed-Muller (RM) codes are among the oldest, simplest and perhaps most ubiquitous family of codes. They are used in many areas of coding theory in both electrical engineering and computer science. Yet, many of their important properties are still under investigation. This paper covers some of the recent developments regarding the weight enumerator and the capacity-achieving properties of RM codes, as well as some of the algorithmic developments. In particular, the paper discusses the recent connections established between RM codes, thresholds of Boolean functions, polarization theory, hypercontractivity, and the techniques of approximating low weight codewords using lower degree polynomials (when codewords are viewed as evaluation vectors of degree r polynomials in m variables). It then overviews some of the algorithms for decoding RM codes. It covers both algorithms with provable performance guarantees for every block length, as well as algorithms with state-of-the-art performances in practical regimes, which do not perform as well for large block length. Finally, the paper concludes with a few open problems. [ABSTRACT FROM AUTHOR]

This is a Special Issue containing selected papers presented at the 5th Euro-Asian Pulsed Power Conference (EAPPC) in Kumamoto, Japan, held on September 8-12, 2014. The present Special Issue continues the tradition of chronicling the latest advances in the domain of pulsed-power science and technology. [ABSTRACT FROM PUBLISHER]

In this paper, we address the consensus tracking problem for the multiagent system (MAS) based on a nonfragile memory sampled-data controller. Considering the effect of controller gain fluctuation and communication delay, a novel sampled-data control scheme with variable sampling interval is designed for each agent. By developing some new terms, an improved piecewise Lyapunov–Krasovskii functional (LKF) is constructed to take full advantage of characteristic about real sampling pattern. Furthermore, some relaxed matrices constructed in the LKF are not necessarily positive definite. Making full use of the LKF and free-matrix-based integral inequality, some sufficient criteria are developed to ensure the consistency of the MAS. Then, by solving a group of linear matrix inequalities with the maximal sampling interval, the desired sampled-data control gain matrix is obtained. Finally, the numerical example of a 5-agent system is given to illustrate the effectiveness of the proposed approach in this paper. [ABSTRACT FROM AUTHOR]

These instructions give guidelines for preparing papers for this publication. [ABSTRACT FROM AUTHOR]

These instructions give guidelines for preparing papers for the IEEE TRANSACTIONS ON CONSUMER ELECTRONICS. The downloaded template must be used. [ABSTRACT FROM AUTHOR]

Skeleton-based human action recognition has been a popular research field during the past few years. With the help of cameras equipping deep sensors, such as the Kinect, human action can be represented by a sequence of human skeleton data. Inspired by the skeleton descriptors based on Lie group, a spatial–temporal skeleton transformation descriptor (ST-STD) is proposed in this paper. The ST-STD describes the relative transformations of skeletons, including the rotation and translation during movement. It gives a comprehensive view of the skeleton in both spatial and temporal domain for each frame. To capture the temporal connections in the skeleton sequence, a denoising sparse long short term memory (DS-LSTM) network is proposed in this paper. The DS-LSTM is designed to deal with two problems in action recognition. First, to decrease the intra-class diversity, the spatial–temporal auto-encoder (STAE) is proposed in this paper to generate representations with higher abstractness. The denoising constraint and the sparsity constraint are applied on both spatial and temporal domain to enhance the robustness and to reduce action misalignment. Second, to model the action sequence, a three-layer LSTM structure is trained with STAE representations for temporal modeling and classification. The experiments are carried out on four popular datasets. The results show that our approach performs better than several existing skeleton-based action recognition methods, which prove the effectiveness of our method. [ABSTRACT FROM AUTHOR]

This paper studies the convex hull pricing problem in electricity markets using a network-flow-based formulation. The network represents the feasible operating region of a generating unit, and the associated flow constraints define a polyhedron with an integrality property. These facts provide modeling flexibility with respect to the inclusion of unit features and allow to obtain convex hull prices from a linear programming problem. The formulation is solved using a primal-dual approach based on the algorithm developed by Bienstock and Zuckerberg. The algorithm, together with the implemented pre-processing and initialization techniques, allows achieving lower solution times than those obtained by state-of-the-art algorithms available in commercial solvers, e.g., barrier and dual simplex. Furthermore, results suggest that the proposed formulation obtains the minimum uplift payments even when time-dependent start-up costs are included, making the approach more robust than the best documented compact formulation. The paper also discusses the effect of sub-optimal prices on uplift payments by relaxing the optimality criterion of the algorithm, observing a significant impact on lost opportunity costs. [ABSTRACT FROM AUTHOR]

This two-part paper is intended to inform power system engineers, electrical engineering academicians, and suppliers of electrical apparatus of the threat of wildfires initiated from mal-operation of electrical grids and the unexploited opportunity to develop proper solutions and preventive means to such lethal events. This part (Part I) reviews and categorizes research in different fields of science and industrial projects that attempt to address wildfire issues. The topics include prediction and prevention means, detection methods, monitoring and surveillance techniques, suppression methods, allocation and mapping algorithms, and a summary of research and educational efforts. Subsequently, this paper highlights the damages and negative effects that a wildfire can cause to the electric grid and the interruptions to its continuous operation. Finally, this paper analyzes and categorizes the various scenarios of faulty electrical networks that may lead to wildfires. Part I of this paper provides the ground work and information for the solutions and discussions presented in Part II. [ABSTRACT FROM AUTHOR]

Contribution: Prior studies on goal congruity show that students are more motivated to pursue careers that allow them to work with and help others and give back to their community (i.e., careers that afford prosocial value). This paper discovers this same pattern in electrical engineering (EE) and discovers that prosocial affordance beliefs are significantly associated with intensions to persist, while agency beliefs are not. Background: Goal congruity theory finds that people are more motivated to pursue a career if it aligns with values they endorse. This theory can shed light on why some students do not persist in EE because of the stereotype that the profession does not allow working with and helping others. Research Questions: This paper seeks to answer whether EE students perceive the profession as affording prosocial value, and to test associations between prosocial perceptions and motivation to persist in the field. Methodology: The first study in this paper was conducted on students in an introductory EE course ($n\,\,= 79$) that measured affordance beliefs about the EE profession and tested associations with intensions to persist. The second study compared affordance beliefs and trait endorsements held by students in the introductory level course with those in an advanced EE courses ($n\,\,=51$). Findings: Mediation analysis revealed that the more novice students believe that EE allows them to fulfill prosocial goals, the greater their persistence intentions (95% CI: 0.01 to 0.34). This analysis also showed that agency beliefs were not strongly associated with persistence intensions. [ABSTRACT FROM AUTHOR]

Contribution: This paper introduces the real-world limitations and non-technical aspects of power electronics (PEs) projects to students through innovative tutorial activities. Background: Many electrical engineering curricula offer a PE courses (PECs) for third- or fourth-year undergraduate students. Prior research on PEs education mainly focused on improving students’ experimental skills through developing practical experiments, laboratory activities, and problem/project-based learning. An instructional approach that instead employs real-world knowledge and skills is worth evaluating. Intended Outcomes: Students should be able to consider real-world technical and non-technical limitations when applying theory to design PE circuits and converters, and be able to select and carry out appropriate tests to troubleshoot circuits. Application Design: Prior research on engineering education emphasized the importance of introducing real-world limitations to the students as part of their curriculum. This paper suggests that the tutorial activities presented in a PEC can help students acquire skills in designing and troubleshooting a circuit or system according to desired technical aspects, real-world limitations, and available data. Findings: Evidence of the validity of this approach in a PEC at two Australian universities, over four academic years, is provided. Students receiving the new tutorial activities had percentage scores some 10–15 points higher than those who had traditional tutorials. Another evaluation reveals the students’ vibrant participation in the activities during the new tutorial sessions. [ABSTRACT FROM AUTHOR]

Contribution: This paper found that design experiences can foster engineering identity and belongingness for early career electrical and computer engineering students. Students had different interpretations of what it meant to be an engineer (identity) and their belongingness in engineering. This paper provides novel insights into how students may be developing identities and belongingness in engineering, both critical for student retention and success. Background: Design experiences are crucial for engineering students, both for developing academic competencies and allowing students to see how they can become engineers. Existing literature has mixed results with respect to the influence of team-based design experiences on engineering identity and belongingness. Research Questions: 1) How do design experiences influence early career electrical and computer engineering students’ identification and belongingness in engineering? and 2) How do these students describe what it means to identify as an engineer and belong in engineering? Methodology: The beliefs of electrical and computer engineering students were examined using mixed methods to understand the intersection of design experiences, engineering identity, and belongingness. Findings: Students interpreted their engineering identity and belongingness differently, particularly, with respect to how design experiences can shape these attitudes. Whereas students interpreted engineering identity through their performance and interest in authentic engineering tasks, they interpreted belongingness as a means of comparing themselves to their peers. The findings have implications for engineering education researchers, and design instructors, to foster ways of being and belonging in engineering. [ABSTRACT FROM AUTHOR]

Background: More than 30 years ago, Harmon distinguished developmental research articles (RAs), which propose a solution to a problem, from experimental RAs, but the developmental format has received little attention. Literature review: Genre analysis of RAs has been largely restricted to articles following the standard experimental/Introduction, Methods, Results, Discussion (IMRD) format, thereby excluding many developmental engineering articles. Recently, a textbook proposed Introduction, Process, Testing, Conclusion (IPTC) as a prototypical format for electrical engineering RAs, but this format has not yet been demonstrated from a corpus. Research questions: 1. What is the macrostructure of electrical engineering RAs? 2. What are the characteristic features of each division of electrical engineering RAs? Methodology: Section headings, wordcount, and notable features were analyzed for 75 RAs from 15 electrical engineering journals and compared with both IPTC and Harmon's developmental structure. Results: Only one article, a case study, followed IMRD. Sixty-seven developmental RAs followed the IPTC format. These are distinguished by the second division (P), where the new solution is described, written in extended style, comprising several sections with headings specific to the research. A paragraph at the end of the Introduction describing the organization of the paper, the location of the theoretical framework and testing methods, and a ubiquitous Conclusion also differ from IMRD. Seven developmental RAs exhibited a hybrid format with the well-known IMRD section headings superimposed on an IPTC structure. Conclusions: Most electrical engineering articles are developmental and follow IPTC format. This can inform future genre analysis research and has pedagogical implications for teaching engineering writing. [ABSTRACT FROM AUTHOR]

This paper develops an accurate small signal model for line commutated converter based HVDC (LCC-HVDC). The overall process of the model establishment is demonstrated from five parts: AC system, DC system, control system, phase-locked loop (PLL) and the converter. Considering the limitations of the traditional converter equations, the proposed small signal model takes the commutation process into account so that the overlap angle and AC current are calculated with the actual value rather than the estimated value. The accuracy of the proposed model is verified both in the time-domain simulation in PSCAD/EMTDC and by eigenvalue analysis. The results show better performance than the traditional modeling methods, which provides valuable guidance for future LCC-HVDC project design. [ABSTRACT FROM AUTHOR]

Contribution: This brief comment highlights some crucial assumptions behind the “law of the junction” that are overlooked by the above paper and argues that the proposed derivation is not actually a “new” derivation at all. Background: The “law of the junction” is one of the most significant and useful results within the field of solid-state devices. The above paper is likely to confuse readers, particularly those who are undergraduate electrical engineering students studying semiconductor device physics for the first time. This is especially so because of the abstract nature of the underlying quantum mechanics framework and solid-state physics models (subjects which the typical student at that level lacks a substantial background in) as well as the plethora of tedious equations in the curriculum. Research Questions: What core physical concepts are essential to a fundamental yet intuitive understanding of the law of the junction? Methodology: Several key features of how semiconductor junctions behave under bias are explained. References to well-known textbooks are provided where appropriate. Findings: The above paper’s primary mistake is its assertion that its derivation does not rely on the assumption of thermal equilibrium. However, the law of the junction is equivalent to a calculation of depletion-edge minority carrier concentrations using Maxwell–Boltzmann statistics—a distribution which only holds under thermal equilibrium conditions. More rigorously, in a nondegenerate semiconductor, Fermi–Dirac statistics (which governs electrons) reduces to Boltzmann statistics only when the electrochemical potential is spatially uniform, a condition equivalent to having no net flow of thermal energy—the very definition of thermal equilibrium. [ABSTRACT FROM AUTHOR]

Announces the winners of the 2003 Outstanding Paper Award by the Institute of Electrical and Electronics Engineers Inc. Ultrasonics, Ferroelectrics, and Frequency Control Society. Overview of the winning paper; Career background of the winners; Comments of award committee members on the winning paper.

A distributed zero-sequence-current (ZSC) carrier signal injection via current transformer (CT) is proposed for underground cable single-phase-to-ground fault location in neutral isolated medium voltage (MV) distribution networks. High-frequency ZSC carrier signal is directly injected to a high-voltage underground cable of an energized distribution network via CT. The injected carrier signal travels along the cable to the receiving center in the substation, and is processed for quick fault line selection and fault location. No external power supplies or signal generators are needed due to the self-contained nature of the injector. The device can be constructed as a sleeve to be mounted around the underground power cable. This permits economical retrofitting to existing installations of power line communication (PLC) devices. In this paper, the operational principle and the application considerations for such an injection device and fault location tricks are explained, followed by the theory behind the proposed technique. Finally, MATLAB based numerical simulations are performed and a low-voltage prototype is tested to verify the validity of the proposed approach. [ABSTRACT FROM AUTHOR]

With the proliferation of distributed generators and energy storage systems, traditional passive consumers in power systems have been gradually evolving into the so-called “prosumers,” i.e., proactive consumers, which can both produce and consume power. To encourage energy exchange among prosumers, energy sharing is increasingly adopted, which is usually formulated as a generalized Nash game (GNG). In this paper, a distributed approach is proposed to seek the Generalized Nash equilibrium (GNE) of the energy sharing game. To this end, we first prove the strong monotonicity of the game. Then, the GNG is converted into an equivalent optimization problem. An algorithm based on Nesterov's methods is thereby devised to solve the equivalent problem and consequently find the GNE in a distributed manner. The convergence of the proposed algorithm is proved rigorously based on the nonexpansive operator theory. The performance of the algorithm is validated by experiments with three prosumers, and the scalability is tested by simulations using 1888 prosumers. [ABSTRACT FROM AUTHOR]

The article offers information on the recipients of the 2007 IEEE Information Theory Society Paper Award. Hanan Weingarten has masteral and doctorate degrees in electrical engineering from the Technion-Israel Institute of Technology. Yossef Steinberg was a Lady Davis Fellow in the Department of Electrical Engineering and held visiting appointments in the Department of Electrical Engineering at Princeton University in New Jersey. Shlomo Shamai has research interests which encompasses a wide spectrum of topics in information theory and statistical communications.

This paper is concerned with the asynchronous fault detection and isolation (FDI) strategy in finite frequency domain for Markov jump systems (MJSs) with actuator failures under networked environment. A set of binary-valued Bernoulli distributed sequences is introduced to describe the transmission and the scheduling of the sensor nodes. Then, an MJS directing by two Markov process and with multiple stochastic parameters is derived to characterize the whole system dynamics. Subsequently, by means of the stochastic $\mathcal {H}_{-}$ index in finite frequency domain and the geometric mapping approach, an asynchronous FDI scheme is investigated, in which the filters complete the FDI mission with only partial information of the measurements. Meanwhile, each FDI filter is only sensitive to one possible actuator fault and decoupled from others. Then the existence of the desired filters is ensured by some novel sufficient conditions. Finally, an application example is presented to show the effectiveness of the proposed theoretical results. [ABSTRACT FROM AUTHOR]

The water system management problem has been widely investigated. However, the interdependencies between water and energy systems are significant and the effective co-optimization is required considering strong interconnections. This paper proposes a two-stage distributionally robust operation model for integrated water-energy nexus systems including power, gas and water systems networked with energy hub systems at a distribution level considering wind uncertainty. The presence of wind power uncertainty inevitably leads to risks in the optimization model. Accordingly, a coherent risk measure, i.e., conditional value-at-risk, is combined with the optimization objective to determine risk-averse operation schemes. This two-stage mean-risk distributionally robust optimization is solved by Bender's decomposition method. Both the day-ahead and real-time operation cost are minimized with an optimal set of scheduling the multi-energy infrastructures. Case studies focus on investigating the strong interdependencies among the four interconnected energy systems. Numerical results validate the economic effectiveness of IES through optimally coordinating the multi-energy infrastructures. The proposed model can provide system operators a powerful two-stage operation scheme to minimise operation cost under water-energy nexus considering risk caused by renewable uncertainties, thus benefiting customers with lower utility bills. [ABSTRACT FROM AUTHOR]

This paper studies the capacity of an $n$ -dimensional vector Gaussian noise channel subject to the constraint that an input must lie in the ball of radius $R$ centered at the origin. It is known that in this setting, the optimizing input distribution is supported on a finite number of concentric spheres. However, the number, the positions, and the probabilities of the spheres are generally unknown. This paper characterizes necessary and sufficient conditions on the constraint $R$ , such that the input distribution supported on a single sphere is optimal. The maximum $\bar {R}_{n}$ , such that using only a single sphere is optimal, is shown to be a solution of an integral equation. Moreover, it is shown that $\bar {R}_{n}$ scales as $\sqrt {n}$ and the exact limit of $\frac {\bar {R}_{n}}{\sqrt {n}}$ is found. [ABSTRACT FROM AUTHOR]

We (people) are memory machines. Our decision processes, emotions, and interactions with the world around us are based on and driven by associations to our memories. This natural association paradigm will become critical in future memory systems, namely, the key question will not be “How do I store more information?” but rather “Do I have the relevant information? How do I retrieve it?” The focus of this paper is to make a first step in this direction. We define and solve a very basic problem in associative retrieval. Given a word $W$ , the words in the memory, which are $t$ -associated with $W$ , are the words in the ball of radius $t$ around $W$. In general, given a set of words, say $W$ , $X$ , and $Y$ , the words that are $t$ -associated with $\{W,X,Y\}$ are those in the memory that are within distance $t$ from all the three words. Our main goal is to study the maximum size of the $t$ -associated set as a function of the number of input words and the minimum distance of the words in memory—we call this value the uncertainty of an associative memory. In this paper, we consider the Hamming distance and derive the uncertainty of the associative memory that consists of all the binary vectors with an arbitrary number of input words. In addition, we study the retrieval problem, namely, how do we get the $t$ -associated set given the inputs? We note that this paradigm is a generalization of the sequences reconstruction problem that was proposed by Levenshtein (2001). In this model, a word is transmitted over multiple channels. A decoder receives all the channel outputs and decodes the transmitted word. Levenshtein computed the minimum number of channels that guarantee a successful decoder—this value happens to be the uncertainty of an associative memory with two input words. [ABSTRACT FROM AUTHOR]

This paper deals with the problem of clearing sequential electricity markets under uncertainty. We consider the European approach, where reserves are traded separately from energy to meet exogenous reserve requirements. Recently, proposed stochastic dispatch models that co-optimize these services provide the most efficient solution in terms of expected operating costs by computing reserve needs endogenously. However, these models are incompatible with existing market designs. This paper proposes a new method to compute reserve requirements that bring the outcome of sequential markets closer to the stochastic energy and reserves co-optimization in terms of cost efficiency. Our method is based on a stochastic bilevel program that implicitly improves the inter-temporal coordination of energy and reserve markets, but remains compatible with the European market design. We use two standard IEEE reliability test cases to illustrate the benefit of intelligently setting operating reserves in single and multiple reserve control zones. [ABSTRACT FROM AUTHOR]

Due to limitations of low power density, high cost, heavy weight, etc., the development and application of battery-powered devices are facing with unprecedented technical challenges. As a novel pattern of energization, the wireless power transfer (WPT) offers a band new way to the energy acquisition for electric-driven devices, thus alleviating the over-dependence on the battery. This paper presents an overview of WPT techniques with emphasis on working mechanisms, technical challenges, metamaterials, and classical applications. Focusing on WPT systems, this paper elaborates on current major research topics and discusses about future development trends. This novel energy transmission mechanism shows significant meanings on the pervasive application of renewable energies in our daily life. [ABSTRACT FROM AUTHOR]

In the event of a single line to ground (SLG) fault in a non-effectively grounded distribution network, the faulted current is weak (only a few amperes or less) and the existing devices cannot accurately judge the faulted feeder. In this paper, we proposed algorithms that combine complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN) and Hilbert transform to construct a multi-criteria comprehensive voting method. First, CEEMDAN algorithm is used to decompose the zero-sequence current to obtain the IMF1(the first intrinsic mode function) component and the Hilbert transform is used to calculate the instantaneous amplitude and instantaneous phase. Then, according to the three largest instantaneous amplitudes information, we constructed the characteristic instantaneous phase, characteristic instantaneous energy relative entropy and characteristic instantaneous zero sequence current polarity criteria from the phase, energy and polarity, respectively. Finally, we proposed a comprehensive voting method, which is specifically shown as follows: when two or more criteria show that one feeder or the bus has an SLG fault, it is voted that the feeder or the bus has an SLG fault. In contrast, if the judgment results of the three criteria are inconsistent, then we would return to recalculation and then vote. Compared with existing method, simulation tests and field experiments show that the method proposed in this paper has higher accuracy and a faster calculation speed. [ABSTRACT FROM AUTHOR]

Foil-winding transformers with high currents in low voltage winding normally have copper/aluminum bars as leads of the coils. A practical solution for locating bar leads without increasing the size of the active part is to flatten the coil in the leads zone causing a deformation. Abnormalities in the leakage reactance have been identified in this type of transformers. In order to take this effect into account, this paper proposes a correction to the mathematical formulation for calculating the leakage reactance in transformers with deformations in the low voltage winding. Three methods for calculating the leakage reactance have been compared for four real case studies: the proposed formulation, the commonly used formulation, and detailed simulations with the finite element method in three-dimension (FEM3D). The leakage reactance calculated with the proposed method has been found to have an improved accuracy compared with the one calculated using the formulation without correction in all case studies. The main contribution of this paper is that the proposed correction in the formulation makes it possible to increase the accuracy in the calculation of leakage reactance, avoiding the need to resort to detailed simulations with FEM3D. [ABSTRACT FROM AUTHOR]

A novel traveling-wave-based fault-location algorithm for multiterminal transmission lines is introduced in this paper. Existing traveling-wave fault-location methods that based on the data measured at line terminals lack reliability and accuracy because time synchronization is needed, which brings error. To solve this problem, the complex structure of multiterminal power system is divided into several fault identification branches, current at the midpoint of each branched is measured, a novel fault-location algorithm is proposed, and the time synchronization error is eliminated. A line-based device is designed to measure the current at the midpoint of each branch. An accurate value of the traveling wave speed can be obtained by merely applying the data record in one measuring device. Thus, the fault-location accuracy is improved. The system model applied in this paper comprises one transmission line and two tapped lines, and the proposed method applies to networks with more terminals. Performance of this method is tested by different cases by PSCAD. The hardware platform has been tested in Sichuan Province, China. [ABSTRACT FROM AUTHOR]

This paper proposes a novel method for voltage dip classification using deep convolutional neural networks. The main contributions of this paper include: 1) to propose a new effective deep convolutional neural network architecture for automatically learning voltage dip features, rather than extracting hand-crafted features; 2) to employ the deep learning in an effective two-dimensional (2-D) transform domain, under space-phasor model (SPM), for efficient learning of dip features; 3) to characterize voltage dips by 2-D SPM-based deep learning, which leads to voltage dip features independent of the duration and sampling frequency of dip recordings; and 4) to develop robust automatically-extracted features that are insensitive to training and test datasets measured from different countries/regions. Experiments were conducted on datasets containing about 6000 measured voltage dips spread over seven classes measured from several different countries. Results have shown good performance of the proposed method: average classification rate is about 97% and false alarm rate is about 0.50%. The test results from the proposed method are compared with the results from two existing dip classification methods. The proposed method is shown to outperform these existing methods. [ABSTRACT FROM AUTHOR]

Circuit models of horizontal and vertical grounding electrodes are traditionally used in high-frequency (HF) analysis, although underlying approximations limit their accuracy in some low-frequency ranges. Recently, a number of new circuit models have been introduced, but the improvement of the accuracy at HF has not been systematically evaluated. In this paper, we show that new circuit models can be directly derived from method of moments solutions of the integral forms of Maxwell equations by introducing different assumptions. This approach helps to categorize different models into only a few categories based on underlying approximations. To determine the applicable range, we analyze the error for impedance to ground computed by different circuit models in comparison to that calculated by a rigorous full-wave model over wide ranges of parameters, such as electrode length, soil resistivity, and frequency. This paper: 1) provides a parametric analysis that enables the estimation of the applicability of the particular circuit model for application to a practical case based on its accuracy; 2) presents a unified systematic approach to derive circuit models with different capabilities; and 3) reveals that the modeling of the mutual coupling between different parts of the grounding electrode is the key factor for radically improving the accuracy of circuit models at HF. [ABSTRACT FROM AUTHOR]

In this paper, an experimental validation of three-dimension multiconductor cell analysis (MCA) is presented: a measurement campaign has been performed on Capri–Torre Annunziata three-core 29.5 km long submarine cable link. All the theoretical conclusions derived by the authors in a previous paper are now experimentally confirmed and the model is, therefore, validated. Based on the example in this paper, the maximum difference between MCA results and measurements is 7% on the positive sequence resistance at power frequency. A 10% difference occurs in the evaluation of positive sequence reactance. The agreement between MCA and real measurements in zero sequence impedance is very good with differences lower than 5% in real and imaginary parts. [ABSTRACT FROM AUTHOR]

A comprehensive time series power flow (TSPF) framework is proposed for the analysis of fault-induced delayed voltage recovery (FIDVR). TSPF bridges the gap between static power flow simulations and time-domain simulations for FIDVR analysis. FIDVR events can be simulated faster with TSPF, while transient simulations normally require much longer time. In the TSPF framework, a random model for the disconnection of the induction motors is proposed to determine the load for different “snapshots” during FIDVR events. Regression analysis is used to predict the parameters needed in the simulations. There is no need to simplify the network topology or aggregate loads into clusters as in measurement-based load modeling approaches. The techniques presented in this paper successfully reproduced two FIDVR events recorded in heavily meshed distribution networks in New York City in 2010 and 2015. The paper uncovers that the proper modeling of motor protections (thermal and under-voltage) is key to properly predict FIDVR events. [ABSTRACT FROM AUTHOR]

An important aspect of ensuring the power integrity of a power distribution network (PDN) design is to determine the layout, value, package size, and number of decoupling capacitors. To solve the limitation of the vertical connection of the surface-mounting-type capacitor to the power net area fill, a new concept of a capacitor denoted the Z-directed component (ZDC) is proposed in this paper. There are many applications possible with the ZDC with the first implementation as a decoupling capacitor. The ZDC capacitors can be integrated within the printed circuit board (PCB) substrate directly below the package ball and eliminate the integrated circuit (IC) to decoupling capacitor horizontal distance across the power net area fill. Furthermore, the inductance associated with the vertical current paths on the vias from the IC package to the horizontal power net area fill and similarly for the surface-mounted technology decoupling capacitors is eliminated. Since only the inductance of the ZDC capacitor itself remains, there is the possibility of using far fewer capacitors to achieve a high-frequency target impedance specification. The ZDC is a promising technology that gives the PCB designer the opportunity to integrate low equivalent series inductance decoupling capacitors much closer to the noise source than traditional surface-mount capacitors. In addition, in this paper, a high-order model is introduced for the ZDC capacitor to better understand the high-frequency characteristics of the component and is verified with measurements. [ABSTRACT FROM AUTHOR]