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Much has been written about specific applications and issues of applying adjustable speed drives. Most of these papers have assumed a comprehensive working knowledge of adjustable speed drives, how they work, and how they are applied. This paper will help engineers and technologists to apply their first adjustable speed drives with little or no applications issues, and act as a reminder to those with previous application experience.

The commissioning phase is the final stage of a project, before production. This is the phase of the project where all the pieces of the puzzle have to come together. The objective of commissioning is to demonstrate to the end user that the goals and objectives specified in the project scope have met the requirements. This paper will focus on premature failures of large motors in the oil and gas industries, which had improper field installation, connections and commissioning. Large horsepower (HP) motors are a key part of most projects and require a great deal of attention to details. Motors require relay protection, writing specifications, vetting suppliers, and testing protocols. The goal is to get desired life expectancy with trouble free service from the motor and the driven equipment. It is clear that good installation is a key to success. Incorrect installation of field connections and field modifications can shorten the life of the motor and instrumentation, and in some cases can lead to premature failures. This applies to a new installation as well as retrofits with an adjustable speed drive (ASD). This paper discusses multiple premature motor failures resulting from improper installations and offers possible protocols that may have prevented equipment failure and the downtime.

Current transformers (CT) produce scaled values of primary currents suitable for protective relays and measuring devices. For correct implementation of protective relays and proper use of their functions, it is important to understand standards to specify the current transformers and how selection of current transformer parameters influences performance of the relays. The same protection relays manufactured by the international manufacturers or by the US manufacturers are used on both international and US projects. However, the current transformers used on international and US projects are different and standards for current transformers, international (IEC) and in the United States (ANSI/IEEE), are different. This paper discusses methods for protective current transformer selection per IEC and per ANSI/IEEE and provides comparison between the two methods. The intention of this paper is to help engineers familiar with one set of standards to better understand definition of protective current transformer parameters in the other set of standards and how current transformer parameter definitions per different standards may influence performance of relays and relaying schemes.

Smart grid systems for onshore oil fields use real-time, high-speed field data from intelligent electronic devices (IEDs) to make fast and intelligent decisions that increase power system reliability and minimize power outages. For an efficient smart grid system, a reliable communications network to the IEDs and centralized controllers is critical for high-speed control and data collection. Communications networks that use conventional fiber networks are not always cost-effective for large dispersed oil fields, which have hundreds of miles of medium-voltage overhead distribution systems. This paper discusses the implementation of a smart grid system for a large dispersed oil field using radios as its communications network. The solution includes high-speed load shedding, online monitoring, event reporting, oscillography, and engineering access. This paper also discusses the process used to design and test the radio technology, including the evaluation of its success metrics, network security, radio path study, and optimization.

Load shedding is critical for facilities that have cogeneration capability to prevent collapse of the cogeneration assets. Fast load shedding requires sub-cycle speed to manage thousands of distributed loads within a facility. This paper describes the experience of applying such a fast load shedding scheme across a wide array of relays provided by various vendors and potentially a large quantity. The system described in this paper utilizes a proven fast load shed system and makes it easy to configure larger and more complex load shed schemes. The paper proposes the architecture of a central fast load shed controller interfaced with local feeder protection relays over IEC 61850 GOOSE and additional fast load shed aggregators if total GOOSE is more than 64. One of the challenges with a large-scale load shed scheme deployment is the configuration of devices, and especially the IEC 61850 GOOSE engineering process which may add further complexity. This paper proposes a simple to configure IEC 61850 GOOSE scheme with high-speed performance requirements. Lessons learned from the fast load shed deployment are also discussed.

At present, more than thirty states across the US have established industrialized modular building certification programs to enforce compliance with state- adopted building and energy conservation codes. While electrical substation enclosures could benefit from energy code exemptions in previous versions of the codes, recent versions of the International Energy Conservation Code (IECC 2015 and later) include electrical substation enclosures within its scope and impose stringent requirements that affect final designs. This paper discusses the design impact of these requirements as it relates to the enclosure envelope (thermal insulation), the mechanical systems (HVAC), and the electrical system (lighting). The paper concludes by presenting possible paths for the industry to challenge some of these requirements and to re-introduce waivers for electrical substation enclosures in the future versions of the IECC.

The authors present a conceptual design for a SMART asset monitoring solution for high voltage (HV) networks in the petrochemical industry. The paper discusses the potential for incorporating artificial intelligence (AI), augmented reality (AR) and virtual reality (VR) into an application of the Industrial Internet of Things (IIoT) for condition monitoring. The paper is a continuation of the work presented by the authors at the IEEE-PCIC 2017 conference in Calgary. The proposed asset management system analyses condition monitoring (CM) data and assesses the risk of failure data across complete HV networks. Knowledge of deteriorating asset condition provides the operator with an advanced, early warning of incipient mechanical and electrical faults. With knowledge of the severity and source of such faults, pinpointed preventative maintenance interventions can then made during planned maintenance outages. The complete HV network asset monitoring solution described includes permanent sensors and monitoring nodes deployed at strategic locations across the network. Processed data is passed via a local area network to local servers and then via secure data cloud transmission to a centralized monitoring server located at the CM headquarters. This central server operates a CM database that logs, displays, benchmarks and trends the condition data with comparison to a statistically-significant database of measurements. It is proposed in the IIoT solution proposed that this database will be downloadable to a smartphone/tablet for use by the field engineer. The monitoring technology will likely also incorporate a number of AI machine learning software modules for the de-noising of raw signals and the diagnosis of different types of defects within different types of HV plant items. The proposed SMART CM system includes an advanced graphical user interface (GUI) for viewing HV asset CM data along with operational and maintenance (O&M) data. The GUI will also be able to display both condition criticality and operational criticality (on a color-coded range of 0-100%) for individual HV plant items on a digitized mimic of the HV network's single-line diagram (SLD). This could also be combined with geometric positioning data of assets across the facility (including HV cable routes and lengths) to provide a fully digitized SMART network diagram for use in the IIoT asset management solution. Asset management data, combined with the application of the developing techniques of AI, AR and VR, will greatly help the user to visualize the plant items in 3-D, their position within the network, their condition and operational criticality along with all related asset management information together on one dashboard screen, downloaded onto smartphone/tablet. The paper concludes with a case study showing the development of a specification for a SMART IIoT asset condition monitoring solution suitable for a large petrochemical refining facility.

Proper communication is a key to performing any task safely. Following standard procedures is absolutely essential for that to work. There is no room for complacency when performing a task based on standard instructions. This paper will discuss the importance and failings of proper communication. First, a simple experiment was conducted around following standard instructions. The results will then be summarized. The paper will then examine two incidents that happened in the low voltage world and the high voltage world as a result of failing follow standard procedures.

In recent years, there has been considerable alignment between the National Electrical Manufacturers Association (NEMA),[1] Institute of Electrical and Electronics Engineers (IEEE), and International Electrotechnical Commission (IEC) Although these standards have largely converged, many differences remain, and, in today's global market, it is important to understand these differences. Our first paper, entitled “Comparison of IEC and NEMA Requirements to Ensure Proper Specification and Design of Induction Motors and Generators for Global Use”,[4] was presented at the Petrolium and Chemical Industry Committee (PCIC) 2017 in Calgary, and focused on the basic performance requirements, mostly covering IEC 60034-1,[2] but also included additional appropriate requirements of critical performance components of 60034–2 [3] through 60034–31. The remainder of the standards are so wide and extensive it was impossible to properly cover them in one paper. Those topics were not covered to their fullest extent and, therefore, will be addressed here, including factory testing, vibration, starting performance, winding impulse and surge capability, efficiency, mounting dimensions, and hazardous area classification. As hazardous area classification comes closer to the division and zone classifications, it is important to understand the remaining differences between the National Electrical Code (NEC) and IEC 60079–7.

Paper investigates the use of newly defined numerical method based on weak-link theory in the context of insulating liquid AC breakdown withstand improvement using impregnated paper coating of the electrodes. It is shown how liquid-impregnated paper differently affects breakdown withstand depending on field non-uniformity. Based on these findings, guidelines for breakdown withstand improvement are presented.

This article studies a paper cutting platform in a comprehensive approach to folk art, folklore, communication, computer and information science focusing on paper-cut in Hebei China. The main content includes:①the data collecting and recording of the scattered Chinese folk paper-cut work in Hebei,②the digitization, optimization, compression, classification, icon and pattern extraction, vectorization and work analysis of the first-hand material, ③the demonstration, dissemination, database construction and retrieval of the classified material, icons and patterns,④ the demonstration of the reconstruction and application of icon and pattern database, and ⑤the design and development of immersive virtual gaming platform of the multi-media scenes and production process of folk paper-cut. In this article, a virtual multi-media system framework of paper cutting is constructed.

Recycled paper is extensively used worldwide. In the last decades its market has expanded considerably. The increasing use of recycled paper in papermaking has led to the production of paper containing several types of impurities. Consequently, wastepaper mills are forced to implement quality control schemes for evaluating the incoming wastepaper stock, thus guarantying the specifications of the final product. The main objective of this work is to present a fast and reliable system for identifying different paper types. Therefore, undesirable paper types can be refused, improving the performance of the paper machine and the final quality of the paper manufactured. For this purpose two fast techniques, i.e., Fourier transform mid-infrared (FTIR) and reflectance near-infrared (*IR) were applied to acquire the infrared spectra of the paper samples. *ext, four processing multivariate methods, i.e., principal component analysis (PCA), canonical variate analysis (CVA), extended canonical variate analysis (ECVA) and support vector machines (SVM) were employed in the feature extraction –or dimension reduction– stage. Afterwards, the k nearest neighbors algorithm (k**) was used in the classification phase. Experimental results show the usefulness of the proposed methodology and the potential of both FTIR and *IR spectroscopic methods. Using the FTIR spectrum in association with SVM and k** the system achieved maximum classification accuracy of 100%, whereas using the *IR spectrum in association with ECVA or SVM and k** the system achieved maximum classification accuracy of 96.4%

Indonesia produces over 350Mt of clean coal in 2012 and is the second largest coal exporter to Japan, accounting for 30 Mt/y. Almost of the coal produced is from open cut mines. Mining operation of open cut mines gives serious impacts on surrounding environment. Therefore, an appropriate rehabilitation program has to be taken into consideration when the mine plan is designed. The basic concept of rehabilitation in open cut mines is the creation of a stable and self-sustaining land surface in post mine surface involved the creation of conditions suitable for the establishment and permanent development of a dense cover of vegetation. Hence, the soil characteristics in rehabilitation area and adequate selection of species to plant in there have to be considered. This paper describes the current situations in rehabilitation area at one of open cut coal mine in Indonesia and then discusses the application of Paper Mulberry as one of effective species planted in post mine surface based on the laboratory tests.

Many engineering students attend their classes and complete their school work for the week, but have little time to ponder their futures. With the help of internships, many students finally have time to realize that there is a much larger goal in their lives beyond just graduating. An internship benefits a student in ways that are not available in a classroom; with interactions among employees and a tremendous amount of experience in the real world career. The North American Pulp & Paper Industry has evolved the internship process into a vast and enlightening learning experience that is preparing future generations of industry engineers that will be vital for continued growth of this phenomenal industry.

Bacterial infections are commonly found on paper towels and other paper products leading to the potential spread of bacteria and consequent health concerns. The objective of this in vitro study was to introduce antibacterial properties to standard paper towel surfaces by coating them with selenium nanoparticles. Scanning electron microscopy was used to measure the size and distribution of the selenium coatings on the paper towels. The amount of selenium precipitated on the paper towels was measured by atomic absorption spectroscopy. In vitro bacterial studies with S. aureus were conducted to assess the effectiveness of the selenium coatings at inhibiting bacterial growth. Results showed that the selenium nanoparticles coated on the paper towel surfaces were well distributed and were semi spherical 50nm in diameter. Most importantly, the selenium nanoparticle coated paper towels inhibited S. aureus growth by 90% after 24, 48 and 72 hours compared with uncoated paper towels. Thus, this study showed that nano-selenium coated paper towels may lead to an increased eradication of bacteria to clean a more wide-range of clinical environments and for the food industry, thus, improving health.

Pulp and paper process residuals are primarily made up of lignin, cellulose and semicellulose. In this study we attempted to apply environmentally friendly and economically feasible technologies to separate and utilize those components for beneficial purposes. Biological acid precipitation was shown to be suitable for the separation of lignin from the process wastewater. In the case of cellulose and semicellulose, bioconversion was explored to produce fuel ethanol using simultaneous saccharification and cofermentation (SSCF). The organic acids (mainly citric acid and acetic acid) produced from Saccharomycopsis Lipolytic can be achieved at the lowest pH (3.6) and in this situation the maximum lignin precipitation (78.6%) occurred. Biological acid precipitation also leads to good removal of COD and color, reaching 87.6% and 68.4%, respectively. Bioconversion of pulp and paper sludge by SSCF resulted in maximum ethanol concentration of 5.69g/L using mixed cultures of Saccharomyces cerevisiae and Escherichia coli KO11.

In this paper we study the radio frequency performance of interconnect using anisotropic conductive film (ACF). A series of experiments are conducted in order to measure and model the electrical characteristics of inkjet-printed circuits on paper substrate as well as the impedance parameters of ACF interconnect at high frequency. Four-point measurement structure, time domain reflectometry (TDR), vector network analyzer (VNA) and de-embedded technology are used to ensure the accuracy of experiments. Equivalent circuit models are built based on the experimental results. Finally, these models are considered as parts of the matching network and circuit design for the RFID receiver, which can be co-designed for developing paper-based electronic systems. It is found that since the difference between RFID tags with and without ACF interconnects is negligible, the influence of ACF interconnects can be ignored for paper-based UHF RFID tag. ACF is a feasible interconnect material for paper-based RFID tags. QC 20111129

The purpose of this study was to examine the photo catalytic degradation of real effluents from wheat straw pulp and paper mill by nano-Fe2O3 catalyst. Four different ferric oxide samples were synthesized by homogeneous precipitation of reflux at different drying and calcination conditions. The most active catalyst was characterized and used as catalyst in photo catalytic degradation process. The effect of key parameters including catalyst dose, solution pH, oxidant concentration were investigated. The results showed UV light alone played a little role in the degradation of wastewater in a short time and the presence of Fe2O3 could greatly promote the degradation of wastewater. The degradation of wastewater was favorable at pH 3. Optimum values of catalyst dose and oxidant concentration was found to be 1 g L-1 and 5 ie (v/v), respectively. Under the optimum condition, the removal rate of COD reached 93.1% under ultraviolet irradiation for 3 h. Satisfactory results suggested the effectiveness of the heterogeneous photo catalytic system ofFe2O3/UV/H2O2 in eliminating COD of paper mill effluent. The COD of effluent was in the range of the acceptable values of the latest China Government standards.

We describe the evolution of a system designed to allow digital grading, by a human, of traditional paper-based exams or homework assignments. We present a number of new features that build upon the system described in a paper previously published in ITiCSE 2008 [1]. In particular, our system now has the ability to monitor an enormous range of data, from individual question scores, to variances for the same questions across different graders, to question and exam statistics from one semester to the next. The system boasts a number of benefits over paper based grading. Overall grading time is reduced — small courses will see a modest improvement, while large courses can see their grading time cut in half due to the automation of many of the tasks: flipping to the correct page, summing up the pages, recording the grades, returning the exams, etc. Rapid grading of exams can also aid students in a better understanding of the material, as the exam questions are still fresh in their minds when the tests are returned. Simultaneous grading across multiple locations is possible, as there is no single paper copy to hand off to the next grader. Permanent digital records are kept of the exams, allowing for viewing of exams at a later date.

Sarawak has a long tradition in the industry of processing flour from the sago palm, Metroxylon sagu Rottboll and is the main exporting State in Malaysia in this commodity. Therefore, the industry has abundant sago waste such as the bark and fiber of extracted sago flour in which the locals use the barks of the trunk as timber fuel, wall materials, ceiling and fence. Fiber of extracted sago flour has also been used as animal feed. However, most are otherwise disposed into the river as waste and become a pollutant. The sago bark and fibers waste materials have been experimentally processed into eco-friendly kraft paper of various textures using a technology of a simple chemically-free kraft paper process. The kraft paper was developed into various types. The cardboard type was found to be suitable for making gift boxes of various designs with uniform consistency and rigidity. Similarly, the paper was found to be suitable for making envelopes, note book cover and souvenir paperbags with good quality. The quality of the bleached sago kraft paper fulfilled the attributes as a media for watercolour painting in terms of its furnish, colour, weight, finish, sizing and dimensions and permanence using watercolour concluded as being able to provide a stable surface media for art and craft works. The demonstration that utilities of sago by-product waste can be converted into kraft paper with good qualities has commercial potential. Thus the the sago waste will not be disposed into the river, thereby reduce the environmental pollution.

A paper mill in Georgia had run a very successful infrared inspection program for a number of years via a local, contract thermographer working with the mill's in-house electricians. Although the program had a good track record, senior management was concerned about the potential impact of NFPA 70E requirements, and how best to comply with them. The plant commissioned a cost-benefit analysis - and this paper will present the results and recommendations from this study.

The pulp & paper industry generates a considerable amount of wastewater in its manufacturing processes. Currently, the pulp and paper industry is facing more stringent standards for discharges of wastewater and associated permits. Biological processes such as activated sludge and aerated lagoons are conventionally used to treat pulp mill effluents. However, these processes have limited ability to provide effluents of high-quality conforming to stringent regulations, since large amounts of lignin and lignin-derived compounds remain in the wastewater. These compounds cannot be metabolized biologically because of their size and complex structure. The objective of this work was to improve the treatment performance of pulp & paper mill effluents, and hence the quality of treated wastewater. For this purpose, a combination of adsorption and coagulation treatment has been proposed. In this study, bentonite was used as adsorbent while PASiC (Polyaluminum Silicate Chloride) was used as coagulant. Respectively, 60.87% of COD removal and 41.38% of color removal can be obtained at the optimum conditions for coagulant dosage and adsorbent are 400 mg/L and 450 mg/L, and adsorption reaction temperature is 30℃, while stirring at the speed of 300rpm for 30min, and the pH value is nature.

Aging of transformer insulating material in natural ester insulating oil was compared to that in conventional transformer oil. Aging of insulating paper has been studied by performing accelerated thermal aging test. Sealed aging test vessels containing copper, laminated core, Kraft/Diamond paper, and insulating oil (natural oil or mineral oil) were aged at 140°C during 500, 1000 and 1500 hours. The extent of paper degradation after aging was determined using paper tensile strength in the aged fluid. The Kraft/Diamond Paper aged in conventional transformer oil degraded at a significantly faster rate than in natural ester insulating oil.

During the last decade the performance of power quality monitoring equipment has increased, while prices of monitors have continuously decreased. Due this trend network operators have more and more intensified their power quality measurement activities. The number of measured parameters and sites is growing continuously. At the same time these new opportunities cause power quality data management and analysis to become an increasing complex challenge. These new challenges will be addressed by the CIGRE working group C4.112 “Guidelines for Power quality monitoring — measurement locations, processing and presentation of data”, which was established in January 2011. The main intention of its work is the development of a coherent set of guidelines for power quality monitoring in existing and future power networks. Based on a clear identification of different objectives all design aspects for an efficient and cost effective power quality monitoring will be covered by the working group in a holistic way. The paper presents first results of the working group and is especially focused on the cost/benefit aspects of the design process of power quality monitoring systems. After a brief introduction the paper gives an overview of the objectives for power quality monitoring and the different aspects that has to be considered while designing a power quality monitoring system. Next the design aspects of larger monitoring systems are discussed in more detail. Some practical recommendations as well as first ideas of new approaches for future monitoring systems are given.

This paper discusses the implementation of NFPA 496 pressurization requirements to install electrical equipment in Class I, Division 2 hazardous classified locations and proposes a solution for a complete integration with HVAC control, fire detection, and gas detection systems.

This paper provides the user of AC electric motors a guide in selecting an electric motor service center and, for those who have made this selection, it provides useful material in performing periodic audits.

In this paper, we review both ANSI/IEEE and IEC short circuit calculation methods. We discuss and compare terminology, definitions, and calculation approaches. We present the advantages and disadvantages of both standards with numerical examples. We analyze identical systems using both methods to make a side-by-side comparison of the results. After both methods are introduced in detail and understood, arc flash calculation examples will be provided using IEC short circuit calculations. Currently, all arc flash calculation methods (including IEEE 1584) focus on three-phase fault currents without being limited to any specific short circuit standard. In our approach, the IEC method can be effectively used for arc calculations. This approach can be utilized in regions of the world where IEC standards are used for short circuit calculations.

This paper presents two alternatives to make choosing the appropriate cost-effective AC machine for a given application easier. One option increases the short circuit capacity (SCC) at the motor bus; the other uses a synchronous machine (SM) in lieu of an induction machine (IM). Both methods have the potential to yield higher efficiency designs with better transient ride-through capability. There are well-defined relationships between applied voltage, applied current, and output torque. In short, higher voltages and/or currents allow a rotating machine to develop more torque. For obvious reasons, this relationship becomes extremely important for the transient performance associated with direct-on-line (DOL) starting. Adding more SCC minimizes the voltage drop, yielding more efficient and less costly designs. Over the life of a typical machine (e.g. 5000 HP IM), even a relatively small efficiency improvement realizes significant savings - enough to purchase the medium voltage (MV) distribution equipment. At 10 000 HP, the efficiency gains achieved through use of a SM instead of an IM are even greater, yielding more savings. As an added benefit, the increase in SCC leads to a more stable system, allowing the motor to ride through low voltage fault conditions that might otherwise have caused a trip. This in turn means more consistent throughput and a more profitable facility.

New draft language for IEEE C37.20.3 - the power distribution standard for metal-enclosed interrupter (MEI) switchgear - proposes, for the first time, permitting the use of isolating switches with vacuum interrupter circuit breakers. This new development would allow an alternative means for disconnecting medium voltage (MV) breakers from a live circuit, more closely approximating the existing IEC standard construction. In accordance with the proposed new language, this paper presents three key developments for MEI switchgear for smaller, lighter, and more reliable solutions that maintain ANSI/IEEE safety and circuit breaker performance characteristics, which are typical of metal-clad (MC) switchgear.

Coordination of large distributed measurement and control systems, like SCADA and other process control demands on infrastructure to handle more network services and implementations, require robust networks that connect thousands of remote devices. There are increased deliver a full spectrum of control and monitoring within global operations. The conventional infrastructure and process automation domains typically don't communicate. The advancement of industrial communications provide value to the industry when logically integrated to combat rising costs. Unifying power and process systems within an operation gives value by creating one visualization and reporting environment. This paper will outline a convergent use of the IEC 61850 standard, within process control networks, to provide enhanced process control, monitoring and energy management. It will discuss benefits of unified power and process architecture with enhancements provided by visualization, archiving, and reporting.

The current development of adjustable speed drives has made voltage source inverter technology available to high power applications such as large axial compressors. Hence, the comparison of voltage source inverter technology to the traditional way of controlling large rotating equipment with load-commutated inverters is of interest. This paper compares the adjustable speed drive systems for shaft powers of 20 MW and more. A drive system includes the drive, the supply network connection and the motor behavior. System reliability and availability are the main drivers, while system efficiency and costs are an additional motivation for the technology positioning. In general, the simple scalability of the load-commutated inverter leads to maximum reliability, especially for very high power. Voltage source inverter technology comes with a higher degree of flexibility in terms of possible output frequencies, cable lengths and type of motor.

All end-users within heavy industry focus on improving ‘Safety’ and some also work on improving ‘Operations Excellence,’ but there are only a few end-users who spend equally as much time on ‘Reliability.’ PCIC is an example of this culture where it has created a standalone safety entity to enhance electrical safety. Unfortunately, in industry, we continue to see significant incidents with loss of life even with this enhanced focus on safety and operations excellence. A three-legged stool is inherently stable and will not rock as a four-legged stool can, but a stool with less than three legs cannot stand. Therefore, the missing leg of the stool is reliability, which has not been a focus area of but a few end-users. In the companies that view reliability (all failures are preventable) on par with safety (all incidents are preventable) equipment failure is addressed proactively to prevent the ‘catastrophic failures' that has led to significant incidents in facilities. This paper will provide a context of the methods for developing a world-class reliability-centric organization.

Rotating machines are widely used in almost all industries as a critical component for process availability. Inadvertent failure of rotating machines causes high repair expenses and loss of revenue. Existing Monitoring and Diagnosis (MD and take control actions. This paper further performs extensive testing of Stator M&D by monitoring the evolution of a stator interturn fault, and also lessons learnt from the site installation of an advanced MPR. Test results are presented from actual field data of a damaged rotating machine as well as a simulated stator-turn fault in a real time environment.

A common assumption is that protective devices, such as circuit breakers, in hazardous areas, such as Class I, Division 1 and 2 or Zone 1 and 2, will work at their designed voltage, current, and short- circuit ratings in the same manner as in non-hazardous areas. However, this is not always true. The electrical components of these protective devices can be affected by the type of enclosure used for their installation within a hazardous area. This paper will explore the characteristics and behavior of the short-circuit ratings for electrical equipment installed in a hazardous area. Some factors, such as the type of flammable and combustible material present, play a role in limiting these short-circuit ratings. In addition, material groups create the atmosphere for installed devices and are a deciding factor on short-circuit ratings.

Partial Discharge (PD) can be a characteristic of incipient failure of bus duct and may be used to detect early deterioration of insulation. Bus duct uses a non-uniform insulation system that relies on air and solid dielectric materials to achieve its dielectric requirements. This insulation system can be modeled as a series/parallel circuit and is susceptible to PD. Location identification of PD could contribute to proactively preventing an arc fault. This paper presents a time-correlated PD measurement acquired through an array of radio frequency antennas within medium voltage bus ducting of various designs. The research presented artificially recreates faults experienced in the field, created in laboratory environment under controlled conditions on medium voltage bus duct. A comparison of varying types of PD will be introduced and a technique developed to automatically detect and pinpoint the position based on the time delay of the measured RF signal as measured through tuned antennas. Bus duct equipped with such monitoring is shown to be a useful detection channel capable of accurate detection and localization over large sections of bus.

Many existing petrochemical facilities are replacing old high voltage (HV) air insulated switchyards (AISs) with new gas insulated switchgear (GIS) substations. Modularization or prefabrication has strategic advantages over site-built substations. While medium voltage (MV) and low voltage (LV) substations have been modularized for many years, the HV GIS substations have not caught up with the construction industry. The modularized HV GIS substations are significantly different compared to other electrical MV or LV substations. This paper addresses the modern philosophy and approach to modularization and how the end-user can benefit, in terms of design flexibility, cost-effectiveness, reduced lead times, premium quality, and accelerated site execution in an operating facility. It describes the technological developments, design concepts, and environmental impact in delivering complete solutions based on site conditions.

This paper explores the various standards and requirements for the certification, selection, use, and installation of cables and cable glands used in explosive gas atmospheres throughout the world. International and North American requirements for cables and cable glands will be examined and compared. In North America, the National Electrical Code (NEC) and Canadian Electrical Code, Part I (CEC) define the requirements for the types of cable that are permitted to be used in different hazardous (classified) locations. In North America, standards exist for certifying cables for use in hazardous locations. These standards have now evolved to allow for additional cable types beyond metal clad (MC) and TECK 90 cables that are primarily used. In Canada, a new edition (2018) of the Hazardous Location Cable and Cable Gland standard has been published, and this should help to clarify the intended range of cable types that could potentially be approved for hazardous locations in Canada. In the United States (US), the NEC defines the types of cables that can be used in hazardous locations, and UL 2225 provides the means to approve Hazardous Location (HL) cables for the US. The International Electro-Technical Commission (IEC) on the other hand does not require cables to be specifically approved for explosive gas or dust atmospheres and instead only provides guidance within IEC 60079–14 on the selection of cables. In all jurisdictions, cable glands for use in explosive gas atmospheres are required to be approved for the location they are being installed in or with a method of protection suitable for the location that they are being installed in, but there are differences in the various standards and requirements.

Sparks and hot surfaces are the most common sources of ignition encountered in hazardous locations. However, there is a struggle with how to deal with electronic devices such as medical devices, cell phones, tablet computers, hand-held devices, etc. in a classified area or “Explosive Atmosphere”. It is quite simple to limit the use of cell phones in an explosive atmosphere, but there is much more to consider for the use of other electronic devices. This issue has become a common concern amongst petrochemical companies. While sparks and hot surfaces bring the main risks associated with the operation of equipment in explosive atmosphere, there are also risks derived from static electricity, lightning, stray currents, radio-frequency radiations, electromagnetic waves produced by radio-frequency (RF) transmitters, and optical radiations such as laser radiation. To aid with a potential solution for this problem, this paper will explore the sources, effects, equipment, protection, and standards in Class I, Division 1 (Zone 1) or Division 2 (Zone 2) locations.

Transformer protection schemes commonly use percentage restrained differential elements for winding protection, often delayed or desensitized by 2nd and 4th harmonic elements during inrush of LV and MV transformer banks. Differential relays are now commonly applied to smaller transformers and the zone of protection can now include cables, bus duct, circuit breakers, and other components. Harmonic controlled differential relays are seeing wider use for arc flash mitigation, and other harmonic-controlled schemes have also been proposed. Preliminary observations suggest that the harmonic spectra of arcing fault currents can differ substantially, which begs the question - when can harmonic-supervised protection be employed with harmonic restraints set to avoid operation for inrush while still operating quickly for arcing faults? This paper explores this topic by analyzing relay responses to real arcing faults using relays from multiple vendors that employ different harmonic detection algorithms.

A new concept of an electric off-shore platform, sized to 55 MW, which is powered from shore via a 161-km subsea cable is currently being commissioned in the North Sea. Only electrical motors drive the rotating equipment such as the compressors and the pumps. The first part of this paper overviews the selected global architecture of electric compression based on three variable speed direct drive solutions for gas exports in term of flexibility, operability, efficiency, compactness of integration and environmental impact. The second part focuses on the motor-compressor technology including the 250 Hz Voltage Source Inverter drive with compact filter and robust control, the gearless rotating equipment combining a TEWAC induction motor and a compressor on active magnetic bearings operating up to 7 MW @ 14500 rpm. The gas string test results are presented validating the system performance and compactness. The conclusion is dedicated to the next generation of mature solutions using standalone and integrated topside or subsea machine improving the system reliability and operability.

Many end users of rotating machinery equipment rely on coast-down and run-up vibration monitoring tests to analyze the vibration characteristics of a machine. However, if the user does not have a full understanding of these tests, the results can be misunderstood. This paper discusses, in depth, what these tests indicate and more importantly, what they do not indicate. It shows how a fundamental understanding of rotordynamics (natural frequencies and forced response vibration) is needed to make practical evaluations of rotating machine design and field performance.

Motor vibrations are tested as a part of Factory Acceptance Testing (FAT), normally on a massive foundation. In 2-pole motors there are two main sources of vibration: rotor unbalance and electrical twice-line frequency excitation. Low vibration implies that the natural frequencies of the motor are separated from the corresponding excitation frequencies. Usually, if the site foundation is rigid, the vibration levels repeat the FAT values with minor changes and are well within the initial limits for condition monitoring. However, if the foundation is flexible, the motor vibration may produce unexpected results. The aim of this paper is to introduce a procedure to help ensure low vibration on site conditions in these cases. The procedure relies on the early cooperation between the motor manufacturer and system integrator based on the horizontal and vertical stiffness of the foundation. The most cost-effective solution can be reached by incorporating proper motor design features in conjunction with the design of the mounting base.

The internet of things (IoT) or industrial internet of things (IIoT) has incredible benefits and potential for much more. It promises vast improvements in operational efficiencies and reduction of catastrophic failure. The full benefits of such technology may be limited by incompatibilities due to manufacturer protocol and device differences. These challenges will be passed on to the user resulting in diminished benefits and frustration if not anticipated and mitigated accordingly. This paper will explore available technologies and address guidelines for future standard and specification development while providing parallels to similar technology introductions in large scale industrial facilities for the review of lessons learned.

Reliably detecting the ignition of an arc flash inside low-voltage metal enclosed switchgear using an arc flash detection system presents a number of technical challenges and requires careful system design to provide maximum equipment and personnel protection. The proper placement of sensors throughout the switchgear is critical to ensuring reliable arc flash detection. Given the large number of potential switchgear design variations, the best way to ensure reliable arc flash detection is through verification of sensor placement by creating true arcing events at a high power test lab using worst-case switchgear configurations in which the detection system will be applied. This paper will briefly discuss the tradeoffs between fiber optic and wired point sensors and will provide extensive treatment of methods to determine sensor placement, sensitivity and quantity within a given low-voltage switchgear design as well as strategies to avoid nuisance operation of the arc flash detection system.

The Runout of a shaft is defined as the deviation of the measured surface from an ideal circle rotating around its rotational axis. The total runout can be split into two main components: the mechanical and the electrical runout. The electrical runout depends on the metallurgical state of the shaft which can only be altered to a certain degree after the forging and heat treatment processes are finished. Especially large shafts for electric motors are prone for high electrical runout, because material imperfections are moved to the center of the shaft by the forging process. As there is an unfavorable ratio between bearing diameter and the largest diameter of the shaft, these imperfections will be in the area of the new shaft surface after machining. Statistics have proven that material inhomogeneity generating an electrical runout occurs in almost all kinds of steel. This paper will provide some information about how to eliminate uncertain material properties causing the electrical runout. One measure will be presented in detail including test results.

Low-impedance generator differential protection is commonly used for detecting stator phase and ground faults in medium-voltage applications. An offshore platform started experiencing sporadic generator differential protection trips during start-up of newly commissioned large water injection pump (WIP) motor rated 4100 kW. The main power sources on the platform are three 16.25 MVA gas turbine generators (GTGs). The GTGs are connected to the 11 kV main electrical distribution system switchgear which also supplies the low-inrush WIP motor started direct-online (DOL). The differential relay trips happened under various loading conditions with one or more GTGs supplying the platform power demand. Site checks and subsequent successful motor starts ruled out any internal fault in the differential protection zone or equipment failure. This paper describes the operating conditions, analysis methods, investigation findings, and proposed solution for the differential relay trip events. In addition, it also provides recommendations for new projects and existing facilities that utilize generator differential protection systems.

Tying a large greenfield plant to an existing and fully operational brownfield facility requires complex planning and modeling. Protection, load shedding, turbine load sharing, synchronization, and other key functionalities must be tested during all phases of the cutover sequence to successfully merge the greenfield and brownfield systems. To validate the effectiveness of these functionalities, a real-time, hardware-in-the-loop, digital simulation can be applied using actual control systems. This paper describes the design, technology, model development, and overall validation of such a hardware-in-the-loop simulation at the largest oil and gas project in the world. This project includes a 1 GW power system distributed over a large geographic region that must run in an islanded configuration when not connected to the local utility of equivalent size. Lessons learned and results from recent hardware-in-the-loop testing are shared.

Through a joint standards development process between the Institute of Electrical and Electronic Engineers (IEEE) and the Canadian Standards Association (CSA), two new standards are now completed. These new standards include a certification standard, IEEE Std 844.1 ™-2017/CSA C22.2 No. 293.1-17 (Standard for Skin Effect Trace Heating of Pipelines, Vessels, Equipment, and Structures-General, Testing, Marking, and Documentation), and an application guide standard, IEEE Std 844.2™-2017/CSA C22.2 No. C293.2-17 (Standard for Skin Effect Trace Heating of Pipelines, Vessels, Equipment, and Structures-Application Guide for Design, Installation, Testing, Commissioning, and Maintenance). Requirements are detailed that have been added or clarified in the skin effect trace heating system certification process. This paper summarizes new applications as well as new recommended installation practices in the application guide. Reflections on the path taken in this joint standard development as well as a look forward at future developments are shared.