The July / August Issue of the Electrical Insulation Magazine has been released. Use the accordion headings below to explore this issue’s content, and visit the IEEE Xplore for full magazine access.

For a list of upcoming conferences, please visit the conference page or check out the events calendar.

Featured Articles

Dielectric Dissipation Factor Measurements on New Stator Bars and Coils—Results from a Global Survey

M. G. Krieg-Wezelenburg
Xplore Link

Comparative Investigation on Fracture of Suspension High Voltage Composite Insulators: A Review—Part II: Chemical Properties and Criteria System

Yanfeng Gao; Xidong Liang; Yi Lu; Jiafu Wang; Weining Bao; Shaohua Li; Chao Wu; Zhou Zuo
Xplore Link

Compatibility of Materials with Insulating Liquids—Why and How to Test

Ivanka Atanasova-Höhlein
Xplore Link


Howard W. Penrose, PhD, CMRP

President, MotorDoc® LLC

From Green Coils to a Green Economy

As global focus turns to the green economy, the challenges that are presented to manufacturers of rotating machinery and insulation material can be daunting. The application of traditional standards and materials to the new applications and rotating machinery designs will, and have, resulted in serious equipment reliability and monitoring problems. A whole new approach is required for practical applications and the use of those standards in everything from smart grid energy storage, hybrid-electric vehicles to Internet of Things (IoT) devices, and sensors to data interpretation.

When the average person is exposed to media reports about zero emissions and the elimination of fossil fuels, they rarely consider the challenges. From the rotating machinery and materials perspective, it can be exciting as new materials, applications, and aging systems develop, especially as the global focus is on the electrification of almost everything. What is the next generation of insulating materials if we lose access to oil? How do we process the materials? What are the impacts? How do we test them?What is the transition?

Right now, we are managing the impacts of traditional manufacturing and repair techniques in generators, transformers, cabling, and other electrical systems in wind power. As noted over the past decade, small deviations in slot wedges and coil design and stator manufacturing have significant effects on the reliability of wind generation. What would pass on a constant-load, ground-based generator has serious implications when the rotating machine is high on a platform with frequent starts and stops and rapidly varying load conditions.The effects of tolerances and thermal cycling becomes critical in large machines that are manufactured to be as cost effective as possible.

When we look to transportation and heavy equipment electrification, the design engineer must consider how the human operator will manage the system. What limitations must be put on a hybrid or electric vehicle to reduce the chaos associated with varying driver styles in order to achieve the perceived reliability of that vehicle on the market? What is the effect of the cooling medium, such as transmission fluid,especially as it ages and carries other contaminants? Although this may become a simpler issue as vehicles move toward driverless, the acceptance of the newer technologies by the public will determine how quickly we move in that direction.

Sensors and prognostics are also accelerating as machine learning and augmented intelligence (AI) techniques continue to advance.Challenges range from ethical use of AI to the reliability of the sensors themselves and how the data are managed. The effects of a faulty sensor, a defect in programming, or even cyber security failures must be considered as all these advances become more automated and connected. The engineer involved in the design of new or modification of existing rotating machinery systems must now understand the effect of connected faults in a far more complex system and consider the new term“resilience.”

Present State

As the renewable energy portfolio continues to expand in the areas of new technologies such as wind, solar, tidal, geo-thermal, battery storage, flywheel storage, and fuel cells and older technologies, the effects on transmission and distribution systems have increased. While new standards, agreements,and smart grid frameworks are being developed, the effect on existing systems is becoming apparent. At the local level, in such locations as wind farms, oil-filled and dry transformer failures are occurring well above the expected failure rates, as are failures in cable splices and generator components such as coils, wedges, and connections. On the larger scale, as electrification increases, regions struggle with meeting demand, and some systems are operating at peak capacity, leaving the systems vulnerable to weather and equipment failures. The component failures range from legacy systems being exposed to new aging systems and unplanned weather exposures to newer systems made from materials with shorter life-cycles. Maintenance and monitoring techniques have also evolved in an environment where cost reductions are a goal. Some Of the changes have been improvements, such as new monitoring systems, and some have been excessive and have had disastrous results, as have been noted since 2003 in the USA alone. As we add additional electrification, such as with electric vehicle charging stations, the effects on transmission, distribution, and generation will continue to increase even as smart grid and smart charging systems develop.

Starting back with deregulation in the 1990s, in the USA, the power-generation landscape changed drastically. From the larger base-loaded plants with spinning reserves, we have moved to a more distributed network of peaking plants and energy storage systems. A natural gas plant, solar or wind farm, geo-thermal facility, or hydro plant can come online from a cold stop far faster than a coal-fired plant or nuclear power. With varying load requirements, the larger coal-fired plants are brought on and removed from production more than in the past, with load variations designed to match customer needs. Although the older plants are operating outside of their original design context, the newer types of facilities are operating with equipment and machines designed with the same standards used to develop the older rotating machines and transformers. The problems become more complex when you add in newer material technology in which limited application experience exists, especially in a variable-demand environment, coupled with the effects of power and home electronics on power quality and homeowners and businesses becoming power producers.

Because wind power is one of the larger utility-scale renewable technologies, and a significant area of material and reliability research, it should receive a little extra consideration. The materials that make up the blades,generator, controls, cabling, and transformers all require attention, with the blades beingsubjected to direct environmental conditions such as weather and location. While off-shore and on-shore wind power have some specific differences, there are some definite similarities. These include wedge issues in the stators and DFIG (doubly fed induction generators) rotors, connections, and coils, which are normally form wound. The ambient conditions are global to the components because the machine is suspended in air, resulting in more drastic thermal cycling with load changes and outages driven by power demand and wind conditions. This affects rotor connections as well as components such as magnetic wedges that are not keyed properly and coil fits in the slots, which can result in grounds. Depending on the design, these three conditions will often rank in the top five reasons for extended turbine outages, with blades and gearbox failures also ranking near the top.

Transportation is having a significant impact as plug-in hybrid-electric and electric vehicles increase in market share, in addition to fuel-saving techniques built into other personal vehicles. For instance, with the use of the autostop function for in-town driving, where a vehicle’s engine turns off at stops (traffic lights and stopped traffic), most of the previous engine and belt-drive components are now electric motor driven. The traction motors in hybrid and electric vehicles vary in type but are generally cooled with transmission fluid and are usually developed as motor generators with permanent magnet rotors. Theinsulation systems used in these technologies are not much different from those used in other commercial or industrial applications but are subjected to rapid changes in operating temperature and load, depending on driving conditions and the operator. Improvements in materials are often implemented, such as the increase in nano-dielectric materials and other specialty wire insulation systems.

The most severe mobile equipment application is hybrid-electric construction machinery with more constant changing loads and variable operation. The studies associated with the insulation system for one large loader with two generators and four switched reluctance machines went about two years. The reliability goals generated completely new materials testing techniques with the goal of accurately determining risk of failure within specific parameters and length of time. Resulting improvements had significant effects on the rotating machine manufacturer’s original designs and material selection. As this sector grows, opportunities for improved insulation material design will be critical, for chemical resistance and thermal aging.

Commercial and industrial electric machines are experiencing changes in design and materials applications. The US Department of Energy has been funding novel approaches to electric machine designs for higher efficiencies including high-speed and high-horsepower compressor motors to reduce powertrain losses. Smaller smart motors are being developed with variable frequency drives being built into the motor frame, with several European fan manufacturers moving from induction motors to brushless DC. A significant consideration in every case is the power quality changes in most facilities as electronics from personal computers to IoT sensors and systems are installed.The need to understand the effect of True Power Factor, in addition to the harmonic conditions and related heating, on the electrical insulation system is second only to the effect of ground“noise” on the insulation systems. Fast-rise-time faults on across-the-line machines that are seeing impulses in the ground system from nearby large variable frequency drives have been confounding technicians at a growing rate.

Possible Future State

Advances in insulating material sciences and research appear to be rising to the challenge. New concepts in self-healing and self-diagnostic systems are in various stages of research and development due to investments in hybrid technology and green-economy rotating machinery and the distribution systems that support them. As we look to a carbon-neutral future, greater political and public pressure will be put on research and development to identify solutions to the electrification of the economy. For rotating machinery there are several directions of research from MEMS (microelectromechanical systems) sensors to materials self-sensoring and new testing technologies to older technologies being applied in new ways.

Although some discuss self-maintaining and self-repairing technologies, tradespeople are working with decades old technology for the prognostics and quality control of in-place and manufacturing process equipment. The challenges relate to the application of these technologies, and their advancement, through the life-cycle of rotating machinery in new environments. For the growing number of smaller electric machines (<700 volts), which include wind turbine generators, traditional testing, such as vibration analysis, has yielded troublingly few findings prior to failure. Older testing methodologies, such as electrical signature analysis, have yielded greater prognostics than expected once they are viewed in a new way. For larger machines (>1,000 volts), the situation is similar in that the noisier environment during operation and the application of traditional technologies becomes more challenging by system. In all cases, offline testing will need to be tailored to the potential operating environment, including the power supply and grounding system.Overall, the ability for AI to assist reliability engineers in modeling and trending a specific machine location and its operation will be critical in providing remaining useful life, or time-to-failure, estimation.

For the rotating machinery and insulating materials industry, the future is electrifying.Although standard technologies will continue, the general trend is toward specialized technologies for many new applications. This means a broader base of rotating machine technologies, the need for faster manufacturing of those technologies, rapid repair turnaround, and earlier fault detection will be required.

Peter Morshuis

Interim Editor-in-Chief
[email protected]

By now, most of us have probably gotten used to communicating with flat faces on screens. In the May-June issue of the Magazine, the Editorial focused on online meetings and conferences. There are definitely positive elements in these online meetings, and we arranged an online survey for DEIS members to share with us their thoughts on conferences, before, during, and after COVID-19. In one of the next issues, we will publish the results of the survey, together with an analysis of what could be the direction for future DEIS conferences.

This issue of the Magazine starts with the results from a global survey on dielectric dissipation factor measurements on new stator bars and coils and continues with the second part of an extensive review on composite suspension insulators. The third article discusses the compatibility between insulating liquids and various materials used in transformers.

The first article in this issue, authored by Monique Krieg-Wezelenburg of High Energy B.V. , the Netherlands, on behalf of Cigré WG A1.39, is titled “Dielectric Dissipation Factor Measurements on New Stator Bars and Coils—Results from a Global Survey.” Dielectric dissipation factor (DDF) measurement is a diagnostic test method used to assess the

manufacturing quality of individual stator bars/coils, and the dielectric behavior of the electrical insulation system of a stator winding is widespread and standardized in IEEE and IEC documents. The requirements specified in the new IEC 60034-27-3 document are viewed by some as too restrictive and by others as overly lenient. Therefore, a CIGRE working group organized an international survey with the aim of collecting worldwide information and data on DDF testing of newly manufactured stator bars and coils. The survey contained questions concerning the use of internal quality standards and limits, the use of international standards, used equipment, and the use of statistical evaluation of DDF results, including the request for measurement results of new bars or coils provided with information such as used guarding technique, applied stress grading, rated voltage, core length, and insulation system. A total of 167 responses were obtained, comprising 119 data sets containing more than 20,000 bar/coil dielectric dissipation factor records. The article provides the key findings of this global survey among owners/users and manufacturers of rotating machines.

The second article is part two of a review in two parts, titled “Comparative Investigation on Fracture of Suspension High Voltage Composite Insulators,” focusing on the chemical properties of all known fracture modes of suspension composite insulators and proposing a novel criterion for discerning fracture modes. It is authored by professor Xidong Liang, Shaohua Li, and Zhou Zuo from Tsinghua University; Yanfeng Gao and Yi Lu from the State Grid Jibei Electric Power Co.; Jiafu Wang from the National Institute of Metrology in Beijing; Weining Bao from China Electric Power Planning & Engineering Institute; and Chao Wu from the University of

Connecticut, USA. This second part of the review focuses on the use of chemical analytical techniques [i.e., Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and thermal gravimetric analysis (TGA)] to study the fracture mechanism. A comprehensive criteria system for abnormal fracture of composite insulators is proposed, based on macroscopic fracture features, microscopic fracture features, and chemical analysis. The authors claim that compared with existing criteria, their novel proposed system is more accurate and systematic, and lays the foundation for accurately discriminating between different fracture types.

The third article is titled “Compatibility of Materials with Insulating Liquids — Why and How to Test,” authored by Ivanka Atanasova-Höhlein of Siemens Energy, Germany. In this article, the need for rigorous compatibility testing of different construction materials and liquid insulation is stipulated, and the consequences are described when this is not being done correctly. Existing standards are discussed, as well as the requirements for compatibility testing. Recommendations are given on the practical compatibility testing, based on procedures that were used successfully for many years. It is concluded that compatibility testing after aging tests should not be restricted to the insulating liquid but also involve the construction materials. The author further suggests that the selected properties shall be chosen in relation to corresponding standards or to required design values. In certain cases, long-term testing can be necessary. Apart from the liquid insulation values, it is advised to also test the gassing behavior of the construction material, to prevent interference with applied diagnostic criteria.


John J. Shea

Handbook of Large Hydro Generators: Operation and Maintenance

G. Mottershead, S. Bomben, I. Kerszenbaum, G. Klempner

IEEE Press/John Wiley and Sons Inc. 111 River Street

Hoboken, NJ 07030

ISBN 978-0-47-094757-9 672 pp., $175, 2021

Hydro generators have been an essential part of the world’s electrical supply for over 100 years and have a power output up to about 1,000 MW. To our knowledge, this is the first book that is specifically focused on how to operate, test, and maintain such machines. This book has a similar format to the well-regarded book Handbook of Large Turbo Generator Operation and Maintenance, written by two of the authors of the hydro generator book (Kerszenbaum and Klempner). This book will be of interest to readers of this magazine because there is a significant focus on the electrical insulation used in hydro generator rotor and stator windings. The main authors are Mottershead and Bomben, who have extensive experience in hydro generator design and operation, respectively. These authors are well known from published papers and their work on IEEE standards working groups. Bomben is currently the chair of the Board of Governors for the IEEE Electrical Insulation Conference.

Handbook of Large Hydro Generators: Operation and Maintenance is a practical handbook for engineers and maintenance staff responsible for the upkeep of large salient-pole hydro generators and pumped-storage generators. It first presents the physics and design of large vertical salient-pole generators. The book then offers readers real-world experience, problem description, and solutions, while teaching them about the design, modernization, inspections, maintenance, and operation of salient-pole machines. One of the best aspects are the explanations of what to look for when doing inspections of the rotor and stators. The book also covers generator protection and auxiliary systems inspection. The final two chapters are dedicated to maintenance and testing, and maintenance philosophies, upgrades, and uprates. Perhaps in a future version of this book they will discuss how to repair hydro generators in more detail.

The handbook includes over 420 full color photos and 180 illustrations, forms, and tables to complement the topics covered in the chapters. Every hydro generating plant in the world should have a copy of this book.

Heat Transfer—Principles and Applications

C. H. Forsberg

Academic Press an Imprint of Elsevier 50 Hampshire Street, 5th Floor Cambridge, MA 02139


ISBN 978-0-12-802296-2

560 pp., $120 (Softcover), 2021

Heat transfer is a fundamental physical phenomenon that is important in many mechanical, electrical, chemical, and civil engineering applications. Understanding heat transfer fundamentals is critical in the design of many applications. Being able to set up and solve heat transfer problems is a valuable skill that can be used by designers and engineers. This book is intended to be for a one-semester course in engineering. The author uses this book to teach a course in heat transfer. It uses Excel and MATLAB programs for numerically solving heat transfer problems that cannot be solved analytically.

The book begins by introducing basic equations for the three modes of heat transfer: conduction, convection, and radiation. It continues with developing heat transfer conduction equations in differential form for rectangular, cylindrical, and spherical coordinates including boundary conditions. One-dimension heat transfer with the analogy to resistance and electric current flow is introduced. Extending these concepts to transient conduction problems is done using a lumped method, the Heisler method, and conduction in semi-infinite solids.

Numerical methods are then presented for both steady-state and transient problems showing how finite difference equations are set up and solved for using Excel or MATLAB. Forced convection and natural (free) convection problems for various geometries are introduced with more specific applications that cover heat exchangers.

The third heat transfer mechanism, radiative heat transfer, is then described. Specific information includes blackbody emission radiation properties, radiation shape factors, radiation shields, and heat transfer between surfaces of an enclosure.

While the previous methods deal with one mode of heat transfer at a time, the author introduces multi-mode problems that involve more than one mode of heat transfer such as conduction and convection. These examples provide practice with more realistic problems because most real-world applications involving transfer of heat include more than one mode.

Mass transfer is also covered in this book. This includes discussion on concentrations and properties of gas mixtures. These solutions would be more applicable to chemical engineers dealing with diffusion, evaporation, venting from containers, and mass transfer through walls and membranes. Other special topics cover thermal contact resistance created by the interfacial connection of two bodies, condensation and boiling heat transfer, and energy usage in buildings.

While there are many heat transfer books that have been published, this one provides clear and concise information and solutions, for both numerical and analytical problems, and can be very useful for setting up numerical problems with a well-known, widely available software—Excel, making solutions to fairly complex problems accessible to nearly anyone with a modern computer rather than only those with access to expensive modeling software packages. This alone makes this book a good choice to learn about heat transfer basics.

Renewable Energy in Power Systems

D. Infield and L. Freris

John Wiley & Sons Inc.

111 River Street

Hoboken, NJ 07030

ISBN 978-1-118-64993-0

346 pp., $60 (Hardcover), 2020

An increasing number of renewable energy sources continue to be connected to existing AC power grids throughout the world, primarily to reduce the dependency on fossil fuels and to reduce greenhouse gas emissions. These sources can produce instabilities and undesired behavior in a power system, especially as the percentage of renewables integrated into the grid increases. By understanding the characteristics of certain renewable energy sources and their associated power conversion equipment, designers and developers can provide more robust grid topologies and controls to insure grid stability, selectivity, protection, and continuity of service.

The main focuses of this book are individual renewable sources [e.g., photovoltaic (PV) arrays and wind generators] and the characteristics of their associated power conditioning equipment including inverters and converters and how these can affect a power distribution network. This includes insights and comparisons between conventional synchronous generation (i.e., mechanical systems with a high inertia) and power electronics with very low equivalent stored inertia. The book also covers network power flow analysis when both renewables and conventional energy sources are tied to the power network. Economic comparisons between renewable and conventional sources, worked examples, and insightful views on future power systems with demand side management are also covered.

Virtually all of this book pertains to AC power transmission and distribution networks. Only a few mentions of DC grids and DC wind power systems are made, so those interested in an all DC distribution system may not find the desired information. But, engineers working in the power sector involved with incorporating renewables into existing AC power systems as well as students wanting to learn more about the challenges of incorporating renewables into the grid will find this book to be especially useful because it contains the necessary background material to understand the technical details behind these combinations of energy sources.

Noise in Radio-Frequency Electronics and Its Measurement

F. Fouquet

John Wiley & Sons Inc.

111 River Street

Hoboken, NJ 07030

ISBN 978-1-78630-532-9

183 pp., $135 (Hardcover), 2020

Wireless communication is a key enabling technology becoming ubiquitous with ever-growing applications of connected devices. However, the performance of wireless communication devices is fundamentally limited by noise sources related to the electronic components used to create these sys-tems. Having a firm understanding of the origins and sources of noise inside radiofrequency (RF) circuits and their effect on telecommunications is vitally important. This book addresses the theoretical aspects of RF noise and its measurement in RF circuits.

This book demonstrates how to calculate noise behavior in a system, modify systems to improve noise performance, and make noise factor measurements. These are done based on a black-box, system approach. Specific practical recommendations are not illustrated, such as PCB board layout or specific electronic component selection, but rather, S-parameters are used to define the system.

The topics begin by covering the fundamentals of electrical noise in general. This covers the origins of background noise (i.e., thermal noise, shot noise) and noise factor measures as related to telecommunications. Next, the Friis formula is introduced. This formula is fundamental to noise measurements and, as such, is thoroughly reviewed and explained to ensure the reader fully appreciates and understands the formula and its use.

The remainder of the book presents examples of noise factor measurements under various conditions that apply to typical RF communication circuits. Some of these include calculating Y and S parameters, using Bosma’s theorem, making noise measurement on a two-port 50-Ω circuit, and characterizing noise in any device. There are also exercises with answers used to apply the methods presented to help reinforce the reader’s understanding and provide worked out examples.

There is also an extensive appendix of supporting materials to help make the necessary calculations. These include admittance parameters and S-parameters for two-port networks, Mason’s rule, and noise power wave concepts.

Although a minimal background in communications theory is needed to fully appreciate this book, it presents a purely theoretical approach to noise characterization in RF circuits with few links to practical methods. Nonetheless, this book is useful for those who need to understand noise theory and develop system methods used to calculate noise factors in RF circuits and options to reduce noise.

Polymers in Organic Electronics

S. Khalifeh

Chemtec Publishing

38 Earswick Drive

Toronto, Ontario M1E 1C6


Distributed by: Elsevier

50 Hampshire Street, 5th Floor Cambridge, MA 02139


ISBN 978-1-927885-67-3

616 pp., $300 (Hardcover), 2020

This book presents key data, recommendations, and methods for designing organic electronic systems using various types of polymers with the intent of helping the reader select an appropriate polymer/polymer chemistry for their organic electronic application. Polymers are classified by family, complexes, composites, nanocomposites, compounds, and small molecules. Some of these include piezoelectric and pyroelectric, optoelectronic, mechatronic, and organic complexes, covering sensors, electro-optics, as well as polymers for packaging.

This is the ultimate book for those who want to get a broad view of the many different types and applications of polymers and electro-active polymers. The basics of polymers are first introduced with specific focus on electronic polymer-based materials. This is very basic but sets the stage for the various uses for each type of polymer.

Electrical conductivity theory is then explained for various classes of polymers used for microelectronics, nanoelectronics, and optoelectronics followed by a broad list of polymers for a variety of applications, some of which include electro-optic, shape memory polymers, light emitting polymers, robotic, and self assembled. Electrical and electro-optic properties are reviewed—transparency, refractive index, absorption, polarization, and luminescence. Polymeric printed circuit boards are reviewed including single-side, double-sided, and multilayer boards; flexible boards; and textile fabricated boards. Polymeric structures made from active organic polymers are detailed covering semiconductors such as diodes and transistors as well as batteries, fuel cells, and piezoelectric devices. Passive organic components, for example, resistors, capacitors, magnets, fiber-optic sensors, antennas, and flexible actuators, are also described.

The book continues to discuss optimizing optical polymers by exploring the chemistry for improving the optical performance of an organic LED and other types of opto-polymers.

The last part of the book discusses various organic electronic packaging options with a focus on enclosing and protecting polymer-based electronic, microelectronic, and nanoelectronic systems from mechanical damage, cooling, RF noise emission, electro-static discharge, moisture, and other environmental conditions. Various different packing types are included such as dual-inline package, through-hole, surface mount, and custom packing techniques.

This book provides material scientists and electro-optic and electronic engineers with a broad selection of ideas for optimizing organic polymerics for a variety of electronic applications. It has just enough technical depth to allow the reader to decide if they want to pursue the methods presented. It is loaded with references for more in-depth study as needed.

Transient Analysis of Power Systems

J. A. Martinez-Velasco, editor John Wiley & Sons Inc.

111 River Street

Hoboken, NJ 07030

ISBN 978-1-119-48053-2

617 pp., $135 (Hardcover), 2020

The Alternative Transients Program (ATP) is a powerful simulation software package for steady-state and transient analysis of power systems. ATP is a version of the Electromagnetics Transients Program developed by the Bonneville Power Administration. Users must sign a license agreement before downloading the software, but otherwise, it is free to use. A number of programs are used to generate, simulate, and analyze ATP cases but are all controllable under one shell program. Uses for this program generally cover time domain simulation including switching transients; circuit breaker transient recovery voltage; capacitor, reactor, transformer, and line switching; statistical performance; faults and series capacitors; overvoltage protection; lightning; relay settings; control systems; frequency scans; sub-synchronous resonance; and harmonic resonance.

This book provides the reader with a clear understanding of the types of studies that can be carried out using the ATP software. The studies presented are considered at an intermediate level for small to medium-size power systems. Beginners could still find this book useful because there is a chapter introducing ATP. However, this book does not show you how to use the ATP program itself; for that purpose, readers should refer to the ATP “Rule Book” which is available online. This book provides practical recommendations for modeling power systems, including models for many electromechanical components such as vacuum interrupters, air circuit breakers, and solid-state switches.

This book can be broken down into two sections. The first section is dedicated to the introduction of the transient analysis of power systems and the ATP capabilities. The remainder of the book covers a large number of some of the most common applications that demonstrate the use of the ATP software tool. There are also a number of complementary collections of data files available on the website for this book by using either the website URL or the QR code available in the book. It does, however, lack examples of distributed energy resources, now beginning to be used in many power systems today. However, that does not mean these systems cannot be modeled; it just means that there are no examples included in this book. Although the ATP can be used for any single or three-phase system, the book is mainly focused on medium and high-voltage application examples with guidance for the methods used to model components typically used in these systems. For example, models for arc interruption processes of a circuit breaker are presented along with many references for additional research. Models for specific components can also be developed by the user if they are not already available in the book or companion database or from online user groups for ATP and related programs.

This book would be of great interest to power engineers or power engineering students who need to analyze power systems, either single-phase or three-phase. Once mastered, the software has very powerful capabilities for in-depth engineering analysis of power systems that can incorporate the electrophysical behavior and statistical nature of many components commonly used in a power system that cannot be modeled in other circuit simulation programs.

Lens Design Basics—Optical Design Problem-Solving in Theory and Practice

C. Gerhard

IOP Publishing Ltd.

Temple Circus, Temple Way

Bristol, BS1 6HG, UK

Phone: +44 (0)117 929 7481

USA Office:

190 North Independence Mall West,

Suite 601

Philadelphia, PA 19106 Phone: +01 215 627 0880 ISBN 978-0-7503-2240-9

62 pp., $159 (eBook), 2020

This is a book on optical lens design, mainly covering the basics of optical system design. Theory is discussed along with practical approaches for solving particular imaging situations. Several case studies also help to illustrate the fundamentals. The reader will gain an understanding of the purposes for many different types of lenses and how to use them to design an optical system.

There are many questions presented in each chapter to reinforce comprehension and help to reflect on the basic phenomena of optical imaging. Info boxes point to exercises in chapter eight where the theory can be applied in hands-on exercises. A list of references provides an overview on additional literature for further study.

The last chapter contains a series of exercises—sorted by subject areas or topics—that represent typical tasks in lens design and optical system design.Different aspects (i.e., the definition of start systems; the creation, evaluation, and optimization of lenses and systems; and the simulation of manufacturing errors and tolerances) are covered. Detailed step-by-step solutions to the exercises are provided in the appendix. The software used for solving the exercises is introduced, and additional information and resources are given.

Finally, the appendix contains a formulary of the most important lens design equations as well as a list of recommended literature.

This book would interest those wanting to learn how to design optical lens systems. It contains the fundamentals to get a beginner designing their own system. The related software is very helpful to get started.