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The article presents the list of reviewers focused on recognition of 2017 transactions and magazine paper.

This paper introduces a speed-sensorless method for detecting rotor asymmetries in wound rotor induction machines working under nonstationary conditions. The method is based on the time–frequency analysis of rotor currents and on a subsequent transformation, which leads to the following goals: unlike conventional spectrograms, it enables to show the diagnostic results as a simple graph, similar to a Fourier spectrum, but where the fault components are placed always at the same positions, regardless the working conditions of the machine; moreover, it enables to assess the machine condition through a very small set of parameters. These characteristics facilitate the understanding and processing of the diagnostic results, and thus, help to design improved monitoring and predictive maintenance systems. Also these features make the proposed method very suitable for condition monitoring of wind power generators, because it fits well with the usual nonstationary working conditions of wind turbines, and makes feasible the transmission of significant diagnostic information to the remote monitoring center using standard data transmission systems. Simulation results and experimental tests, carried out on a 5-kW laboratory rig, show the validity of the proposed method and illustrate its advantages regarding previously developed diagnostic methods under nonstationary conditions. [ABSTRACT FROM AUTHOR]

Dynamic frequency regulation and effect of penetration of static and inertial sources on system stability are important issues for islanded microgrid power quality and reliability. This paper presents a novel strategy of utilizing an inverter-based source as a voltage source inverter or virtual synchronous generator (VSG). Electromechanical and power modes are critical for small signal stability of an isolated microgrid having static and inertial sources. Interaction of these modes is analyzed through eigenvalue analysis of microgrid model and differential equations describing respective modes. Inertia is important for providing fault current, determining steady state and transient stability, and better system frequency profile. A novel technique is proposed to include inertia virtually to the inverter-based sources by adding swing equation. Furthermore, inverter-based sources with traditional and modified droop controls and VSGs are compared with respect to inertia, energy, and stability. The proposed control and stability comparison are verified through experimental microgrid setup having three inverter-based sources, which can be alternately operated as VSGs. [ABSTRACT FROM AUTHOR]

Over the past 12 years, a number of changes and enhancements have been made to the Spreadsheet Electrical Reliability Model that was introduced at the 1994 IEEE Petroleum and Chemical Industry Committee (PCIC) Conference. Several papers have been written since then, addressing some of the changes. Papers have also been written related to the application of the spreadsheet methodology to the IEEE Gold Book standard net- work. This paper will briefly review the history of the Spreadsheet Modeling technique and review features of the latest version. This paper discusses the impact that common causes can have on industrial electrical system reliability analysis. This paper also introduces an alternate network for evaluating reliability analysis methodologies. As in the past, the latest version of the Spreadsheet Model will be made available as free shareware on the PCIC web site. [ABSTRACT FROM AUTHOR]

Voltage dips are often responsible for disrupting the operation of sensitive electronic equipment. In this paper, two solutions are presented to prevent sensitive equipment from disruptive operation. Both solutions make use of distributed generation systems to maintain the voltage across the equipment in the presence of voltage dips. The emphasis of this paper is on the transient re. spouse of both solutions to balanced as well as unbalanced voltage dips. Simulations have been carried out to provide a thorough analysis. [ABSTRACT FROM AUTHOR]

This is one of a series of papers discussing the application and accuracy of different analysis techniques supporting the determination of industrial and commercial power system reliability and availability. There is a need recognized in the power industry to identify and utilize a standard tool, or a set of tools, to analyze the reliability of power systems. historically, the results of applying different reliability methodologies and tools varied significantly, and comparisons were difficult. The Reliability Analysis Techniques Working Group of the Gold Book (WEE Std. 493-1997) developed a standard network to enable comparison of analytical techniques. This paper describes the approach of simulations via reliability block diagrams as applied to the Gold Book standard network. Reliability indexes of the load points are presented, and are compared with ones obtained from other techniques in the series to determine the accuracy. [ABSTRACT FROM AUTHOR]

Current control in inverter-driven machine systems is the inner most component of the hierarchy of control loops. If the control of current in the machine is not fast and accurate then it is difficult, if not impossible, to build a high-performance drive system. Unfortunately, the implementation of current control in power electronic systems is not ideal. Practical effects can have a significant influence on its performance. This paper examines one of these effects, dead time, and considers the influence it has on the performance of predictive current controllers (PCCs). The paper presents analysis that shows that a PCC implicitly compensates for voltage loss due to dead time. Also, a modified PCC is introduced that reduces the zero-current-clamp problem caused by dead time. Simulation and experimental results are presented to verify the analysis and confirm the performance of the new algorithm. [ABSTRACT FROM AUTHOR]

This paper discusses typical grounding practices and ground fault protection methods for medium-voltage generator stators, highlighting their merits and drawbacks. Particular attention is given to applications of multiple generators connected to a single bus. The paper also provides an overview of the generator damage mechanism during stator ground faults. Problem areas associated with each type of grounding are identified and solutions are discussed. The paper also provides a list of references on the topic. The paper is intended as a guide to aid engineers in selecting adequate grounding and ground fault protection schemes for medium-voltage industrial and commercial generators for new installations, for evaluating existing systems, and for future expansion of facilities, to minimize generator damage from stator ground faults. These topics are presented in four separate parts, Parts 1-4. Part 1 covers scope, introduction, user examples of stator ground failure, and theoretical basis for the problem. Part 2 discusses various grounding methods used in industrial applications. Part 3 describes protection methods for the various types of grounding and Part 4 provides a conclusion and bibliography of additional resource material. [ABSTRACT FROM AUTHOR]

This paper discusses typical grounding practices and ground fault protection methods for medium-voltage generator stators, highlighting their merits and drawbacks. Particular attention is given to applications of multiple generators connected to a single bus. The paper also provides an overview of the generator damage mechanism during stator ground faults. Problem areas associated with each type of grounding are identified and solutions are discussed. The paper also provides a list of references on the topic. The paper is intended as a guide to aid engineers in selecting adequate grounding and ground fault protection schemes for medium-voltage industrial and commercial generators for new installations, for evaluating existing systems, and for future expansion of facilities, to minimize generator damage from stator ground faults. These topics are presented in four separate parts, Parts 1-4. Part 1 covers scope, introduction, user examples of stator ground failure, and theoretical basis for the problem. Part 2 discusses various grounding methods used in industrial applications. Part 3 describes protection methods for the various types of grounding and Part 4 provides a conclusion and bibliography of additional resource material. [ABSTRACT FROM AUTHOR]

This paper discusses typical grounding practices and ground fault protection methods for medium-voltage generator stators, highlighting their merits and drawbacks. Particular attention is given to applications of multiple generators connected to a single bus. The paper also provides an overview of the generator damage mechanism during stator ground faults. Problem areas associated with each type of grounding are identified and solutions are discussed. The paper also provides a list of references on the topic. The paper is intended as a guide to aid engineers in selecting adequate grounding and ground fault protection schemes for medium-voltage industrial and commercial generators for new installations, for evaluating existing systems, and for future expansion of facilities, to minimize generator damage from stator ground faults. These topics are presented in four separate parts, Parts 1-4. Part 1 covers scope, introduction, user examples of stator ground failure, and theoretical basis for the problem. Part 2 discusses various grounding methods used in industrial applications. Part 3 describes protection methods for the various types of grounding and Part 4 provides a conclusion and bibliography of additional resource material. [ABSTRACT FROM AUTHOR]

The value proposition for the installation of power factor (PF) correction (PFC) to avoid costly utility penalties is easily understood. The attractive payback of such PFC opportunities often pushes the project ahead without engineering considerations. In the case of medium-voltage PFC, lack of upfront engineering can lead to unexpected consequences in the performance of the PFC equipment ranging from nuisance trips and blown fuses to catastrophic failure in the extreme. In this paper, the authors propose a systematic approach to the design of PFC for medium-voltage systems. Three actual case studies were selected to illustrate this systematic approach and show that it can be applied regardless of the size, type, and complexity of the facility. Such a methodology is composed of load flow and harmonic measurements, harmonic analysis, utility billing demand and PF analysis, and reactive compensation specification in the form of either capacitors or harmonic filters, if needed. Diverse and competing design constraints, including daily and week load cycles, nearby utility capacitors, switched or stepped requirements, specifics of utility tariffs, loads with high harmonic content, and harmonic resonance, are identified, analyzed, and then incorporated into the solution to ensure successful performance of the PFC equipment. [ABSTRACT FROM PUBLISHER]

Some of the modem voltage regulator systems are utilizing the proportional, integral, and derivative (PID) control for stabilization Two PID tuning approaches, pole placement and pole-zero cancellation, are commonly utilized for commissioning a digital excitation system. Each approach is discussed including its performance with three excitation parameter variations. The parameters considered include system loop gain, uncertain exciter time constants, and forcing limits. This paper is intended for various engineers and technicians to provide a better understanding of how the digital controller is tuned with pros and cons for each method. [ABSTRACT FROM AUTHOR]

IEEE standards and test procedures are widely used by motor and generator vendors and users to commission windings in new machines, as well as evaluate the condition of the winding insulation in operating machines. Until recent revisions, the basic procedures and standards in use were written over 25 years ago. Since the 1970s, motor windings have encountered many changes in their design and manufacture. The result was that the interpretation of results in many of the standards was no longer valid for the more modern motors. Over the past five years, the IEEE Power Engineering Society has conducted a major review and updating of most of these standards. Many important changes in test procedures and interpretation guidelines have resulted. This paper reviews the main insulation standards used for stator and rotor winding diagnostic testing, and discusses the changes that have been made. Standards discussed include: IEEE 43, 56, 95, 286,522, and 1434. For example, IEEE 43-2000 now requires a minimum insulation resistance of 100 M&Ohm; for new stator windings rated 2300 V or more, rather than the "kV + 1" that was required in the past. Furthermore, the interpretation for polarization index has changed such that a motor with a polarization index of 1 is no longer automatically classed as "bad." [ABSTRACT FROM AUTHOR]

The application of forensic science techniques to electrical equipment failure investigation has not been widely documented in the engineering world. This paper is intended to share an example of using material characterization techniques to support an initial cause determination of an electrical component "failure" event The resulting conclusion supported the initial cause determination and ruled out the possibility of design deficiencies. Thus, the qualification testing of the equipment was allowed to continue to successful completion. [ABSTRACT FROM AUTHOR]

Industrial manufacturers strive to maximize uptime of plant operations and processes. However, downtime can be a valuable asset and present many opportunities to address those critical maintenance items that can impact reliability. Since motors and associated driven equipment comprise almost 90% of the process loads, identifying and correcting these mechanical and electrical maintenance problems will reduce unplanned production shutdowns and significantly increase business profits. This paper explores the various protection technologies available to the plant and design engineer for implementation of a cost effective and reliability centered motor management program. [ABSTRACT FROM AUTHOR]

A four-quadrant sensorless controller for switched reluctance motor (SRM) drives is presented in this paper. The drive system with appropriate turn-on and turn-off angles for each operating quadrant delivers excellent dynamic performance over a wide speed range including zero speed. The problems associated with practical implementation especially at low and zero speeds have been addressed and overcome with engineering solutions. Experimental results for a 1-kW SRM obtained on a dSPACE-based system are presented along with useful guidelines for practical implementation. [ABSTRACT FROM AUTHOR]

The article presents comments of the author on researcher A.D. Stokes and D.K. Sweeting's study "Electric Arcing Burn Hazards." The paper succeeded in relating theoretical electrical power system arcing fault energy to the possible incident energy on employees in a quantitative way. It was the origin point for all arc-flash incident energy studies and programs. It enabled the development of a model that simulates the real world case where protection may be set for a relatively long time. Various tests showed that the possible arc projection distance is much smaller for equipment with short horizontal buses.