By Topic

Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

Cover Image Copyright Year: 2014
Author(s): Stone, G.; Culbert, I.; Boulter, E.; Dhirani, H.
Publisher: Wiley-IEEE Press
Content Type : Books & eBooks
Topics: Components, Circuits, Devices & Systems ;  Fields, Waves & Electromagnetics ;  Power, Energy, & Industry Applications
  • Print

Abstract

A fully expanded new edition documenting the significant improvements that have been made to the tests and monitors of electrical insulation systems

Electrical Insulation for Rotating Machines: Design, Evaluation, Aging, Testing, and Repair, Second Edition covers all aspects in the design, deterioration, testing, and repair of the electrical insulation used in motors and generators of all ratings greater than fractional horsepower size. It discusses both rotor and stator windings; gives a historical overview of machine insulation design; and describes the materials and manufacturing methods of the rotor and stator winding insulation systems in current use (while covering systems made over fifty years ago). It covers how to select the insulation systems for use in new machines, and explains over thirty different rotor and stator winding failure processes, including the methods to repair, or least slow down, each process. Finally, it reviews the theoretical basis, pra tical application, and interpretation of forty different tests and monitors that are used to assess winding insulation condition, thereby helping machine users avoid unnecessary machine failures and reduce maintenance costs.

Electrical Insulation for Rotating Machines:

  • Documents the large array of machine electrical failure mechanisms, repair methods, and test techniques that are currently available
  • Educates owners of machines as well as repair shops on the different failure processes and shows them how to fix or otherwise ameliorate them
  • Offers chapters on testing, monitoring, and maintenance strategies that assist in educating machine users and repair shops on the tests needed for specific situations and how to minimize motor and generator maintenance costs
  • Captures the state of both the present and past “art” in rotating machine insulation system design and manufacture, which helps designers learn from the knowledge acquired b lux 384

    15.30 Rotor Single-Phase Rotation 385

    References 385

    CHAPTER 16 IN-SERVICE MONITORING OF STATOR AND ROTOR WINDINGS 389

    16.1 Thermal Monitoring 390

    16.2 Condition Monitors and Tagging Compounds 395

    16.3 Ozone 398

    16.4 Online Partial Discharge Monitor 400

    16.5 Online Capacitance and Dissipation Factor 415

    16.6 Endwinding Vibration Monitor 417

    16.7 Synchronous Rotor Flux Monitor 420

    16.8 Current Signature Analysis 427

    16.9 Bearing Vibration Monitor 432

    16.10 Stator Winding Water Leak Monitoring 435

    References 435

    CHAPTER 17 CORE TESTING 439

    17.1 Knife 439

    17.2 Rated Flux 441

    17.3 Core Loss 450

    17.4 Low Core Flux (El-CID) 451

    References 461

    CHAPTER 18 NEW MACHINE WINDING AND REWIND SPECIFICATIONS 463

    18.1 Objective of Stator and Rotor Winding Specifications 464

    18.2 Trade-Offs Between Detailed and General Specifications 464

    18.3 General Items for Specifications 465

    18.4 Technical Requirements for New Stator Windings 467

    18.5 Technical Requirements for Insulated Rotor Windings 475

    References 486

    CHAPTER 19 ACCEPTANCE AND SITE TESTING OF NEW WINDINGS 487

    19.1 Stator Winding Insulation System Prequalification Tests 487

    19.2 Stator Winding Insulation System Factory and On-Site Tests 494

    19.3 Factory and On-Site Tests for Rotor Windings 501

    19.4 Core Insulation Factory and On-Site Tests 505

    References 506

    CHAPTER 20 MAINTENANCE STRATEGIES 509

    20.1 Maintenance and Inspection Options 509

    20.2 Maintenance Strategies for Various Machine Types and Applications 515

    Reference 525

    APPENDIX A INSULATION MATERIAL TABLES 527

    APPENDIX B INSULATION SYSTEM TABLES 553

    INDEX 629

  •   Click to expandTable of Contents

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      FrontMatter

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.fmatter
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter contains sections titled:
      Half-Title
      Series Page
      Title
      Copyright
      Contents
      Preface View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Supplemental Images

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ins
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      The color illustrations for Chapters 8, 13, 15, 16 and 17 are included, as follows:
      Figures 8.7, 8.8, 8.18, 8.20
      Figures 13.7
      Figures 15.6, 15.9, 15.11
      Figures 16.14, 16.15
      Figures 17.20, 17.21 View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Rotating Machine Insulation Systems

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch1
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      Electrical machines rated at about 1 HP or 1kW and above are classified into two broad categories: (i) motors, and (ii) generators. The stator winding and rotor windings consist of several components, each with its own function. Different types of machines have different components. Stator and rotor windings are discussed separately in this chapter. The stator winding insulation system contains several different components and features, which together ensure that electrical shorts do not occur, that the heat from the conductor I2R losses is transmitted to a heat sink, and that the conductors do not vibrate in spite of the magnetic forces. Electrical insulation is present on the salient pole and round rotor types of synchronous motors and generators, as well as wound rotor induction motors and generators. The rotor windings in synchronous motors and generators are subject to relatively low DC voltage, unlike the high AC voltage on the stator. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Evaluating Insulation Materials and Systems

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch2
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes the practical aspects and limitations of accelerated aging tests used to determine the capability of winding insulation systems. There are many different stresses that can affect the rate of insulation deterioration in stator and rotor windings. The chapter describes thermal, electrical, ambient, and mechanical stresses, the so-called TEAM stresses. Each insulating material has its characteristic breakdown strength. Elaborate methods have been developed for measuring the short-term (voltage is applied for less than a few minutes) breakdown strength of insulation. The notion that some failure processes in rotor and stator windings do not occur as a result of a single stress or factor but, in fact, depend on two or more stresses/factors. Thus, to reasonably duplicate some failure processes in an accelerated aging test, more than one stress needs to be applied at the same time. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Historical Development of Insulation Materials and Systems

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch3
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes the chronological development of insulation materials and systems, together with some of the key innovations in manufacturing. It describes the historical development of all the main materials used in rotor and stator windings. For lower voltage form-wound stator coils, a varnish made with drying-oil based paints was applied to the coil surface to give some protection against contaminates in service, such as lubricating oils and cleaning materials. In 1950, insulation engineers started to investigate the proliferation of new materials made with synthetic plastic films and later, polymer-fiber-based nonwovens, being offered by suppliers as slot, turn, and phase insulations for random-wound induction motors. One of the major developments was the replacement of thermoplastic solvent-borne natural and synthetic resins with solventless synthetic resins. The Russian mica became known as muscovite, the term still used to describe white or India mica. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Stator Winding Insulation Systems in Current Use

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch4
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter reviews the state of the art in the manufacturing of random- and form-wound stator coils, and presents the known characteristics of the major commercially available form-wound coil and bar insulation systems. A review of some very recent developments is also presented. One of the interesting trends of the past decade or two has been the merging of many motor and generator manufacturers; accordingly the chapter provides an indicative list of the mergers. In addition, some major brands routinely use other manufacturers to make certain sizes of machines. The insulation systems in current use by most random-wound motor stator suppliers are usually not differentiated by trade names. Instead, most manufacturers use similar materials, although of course manufacturing processes may be different in detail. The chapter describes the main features of current random-wound stators such as magnet wire insulation, phase and ground insulation, and varnish treatment and impregnation. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Rotor Winding Insulation Systems

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch5
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter outlines where insulation is needed and the stresses that act on the insulation for the various rotor winding components such as windings, slip rings, retaining rings, end winding banding, etc. Rotor winding insulation is exposed to stresses that are different from those in the stator winding. Most types of rotors in motors and generators, except the SCI type, have both ground and turn insulation. Collector rings are also needed for wound induction rotor motor windings. The retaining ring insulation is inserted between the radial outer (or top) of the field coils and the retaining rings. A number of materials have been used for retaining ring insulation. More complicated designs for direct-cooled rotors for the largest generators utilize hollow sections of copper for the slot sections of the coils and partially for the copper under the retaining rings. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Rotor and Stator Laminated Cores

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch6
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter discusses rotor and stator cores and, in particular, steel lamination and insulation on these laminations, as well as how the laminations are fabricated into cores. It restricts the materials, processes, and insulation of laminated stator and rotor cores, that is, electromagnet application. Magnetic fields are characterized by the magnetic flux, the magnetic flux density or B, and the magnetic field intensity or H. The latter is called the magnetomotive force or mmf when the field is generated by an electromagnet. Laser cutting is also used for limited new production and prototypes, for modifications of laminations from existing dies or punched stock, and to replace damaged laminations during core repairs. The annealing is carried out in an inert atmosphere to prevent oxidation of the metal surface. Burr removal is often done by a grinding or sanding operation that also leaves some bare metal where the burrwas removed. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      General Principles of Winding Failure, Repair and Rewinding

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch7
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes why there are so many failure processes and what causes one process to dominate, eventually leading to failure in a particular machine. It presents information on how to select an appropriate repair method from all the possible options. Some machine failures, which are identified by a stator ground fault, rotor ground fault or extremely high vibration, occur as a result of a catastrophic event, regardless of the original condition of the insulation. Form-wound stator windings that experience localized damage during maintenance, or fail in service, can sometimes be repaired in a short outage/turnaround, and returned to service in a few days. When one or a small number of coils or bars have been damaged as a result of manufacture, maintenance or an in-service fault, it is often not possible to repair the coil/bar. Rewinding implies that the core will be reused. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Stator Failure Mechanisms and Repair

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch8
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter presents the main aging and failure mechanisms of stator windings, as well as the options associated with each mechanism for repairing the stator or altering its operation to extend winding life. The only failure mechanisms discussed here are those that are due to gradual aging of the winding. Some of the failure mechanisms will only occur on form-wound stators, and some only in random-wound stators. However, many of the failure processes can occur in either type of stator. The chapter discusses the relevance of the failure process for both random-and form-wound stators. The symptoms for each failure mechanism are also described. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Round Rotor Winding Failure Mechanisms and Repair

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch9
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes the aging processes and failure mechanisms affecting rotor winding insulation and, where appropriate, the winding conductors of round rotors in turbine generators and high speed synchronous motors. The repairs covered in it tend to be common for all types of deterioration processes. Thermal degradation of these materials may be treated as a chemical rate phenomenon and includes loss of volatiles, oxidation, depolymerization, shrinkage, surface cracking, and embrittlement. Peaking units are more susceptible to thermal cycling damage compared to base-loaded units because of the higher number of start-stop cycles. Repetitive voltage surges can result in turn-to-turn shorts. The first such short may not be evident during operation unless the generator is fitted with a flux monitor. The effects of centrifugal forces are a function of the design of winding bracing system, the properties of the materials used, and the frequency of start and stop cycles. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Salient Pole Rotor Winding Failure Mechanisms and Repair

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch10
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      Modern salient pole winding designs use aramid paper ground and turn insulation in strip-on-edge windings, resin-bonded glass laminate pole washers DacronTM and glass-covered high-temperature enamel turn insulation in wire wound poles, and thermosetting bonding resins. Insulation aging from thermal cycling occurs mainly in synchronous motors and generators that are started and stopped frequently. Salient pole rotor windings, especially strip-on-edge types, are generally susceptible to failure from contamination by conducting materials because they rely on adequate creepage distances between bare copper conductors to prevent shorts. Abrasive dust from the surrounding atmosphere carried into the interior of a motor or generator by cooling air will abrade the rotor winding insulation surfaces. Among the most common causes of failure in salient pole rotor windings are the continuous centrifugal forces imposed on them by rotation and the cyclic centrifugal forces induced by starting and stopping. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Wound Rotor Winding Failure Mechanisms and Repair

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch11
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      In a wound rotor induction motor or generator, there is a transformer coupling effect between the stator and rotor windings. Unbalanced stator winding power supply voltages will induce negative sequence voltages and currents in the rotor winding. If a joint between two conductors has been poorly soldered/brazed or the compression clip joint poorly made, it will present a high resistance to the current flowing through it under load and this will produce overheating of the joint insulation. Application of banding over the rotor end windings is required to brace them against the high centrifugal forces imposed on them during operation. The three slip rings in a wound rotor motor must be separated from the shaft by a layer of insulation applied between the two. The spacing between the rings must be sufficient to provide an adequate electrical creepage distance and in some designs insulating barriers are used to achieve this. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Squirrel Cage Induction Rotor Winding Failure Mechanisms and Repair

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch12
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      Although most squirrel-cage rotor windings are not insulated, they can fail due to various aging mechanisms, which can be thermal, electrical, or mechanical in nature. Their susceptibility to failure is dependent on the type of winding construction, the motor application, operating duty, winding geometry, and the materials of construction. Although motors used in centrifugal pump applications very seldom experience winding failures, those used in high-inertia drive systems such as power station induced-draft fans are most susceptible, especially if they are frequently started directly-on-line. There are a number of contributors to cyclically induced stresses in squirrel cage rotor windings and these can cause failures due to low-cycle fatigue. There are a number of design and manufacturing deficiencies that can cause failure on their own, accelerate the failure mechanisms and/or give unacceptable motor performance. Squirrel-cage winding repair techniques are very much dependent on the type of winding. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Core Lamination Insulation Failure and Repair

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch13
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter discusses the most common causes of stator and rotor core failures in both induction and synchronous machines, together with proven repair methods. Degradation of the core condition due to the effects of thermal aging can occur in all rotating machine laminated cores. Electrical aging occurs when the voltage across the lamination insulation induced by magnetic fluxes, electromagnetic forces, or high ground-fault currents causes deterioration. The most common causes of mechanical degradation in cores are inadequate core pressure applied in manufacture, core pressure reduction in service due to relaxation of the core support structure, core vibration, back-of-core looseness, and mechanical damage causing smearing of the core surface at the bore. A number of different core insulation defects can be introduced during manufacture and these may not be detected if adequate quality assurance (QA) checks are not performed. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      General Principles of Testing and Monitoring

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch14
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes on-line and off-line tests and monitors that can be used on rotor and stator windings, as well as stator and rotor laminated cores. It discusses several issues that are common to all of the tests and monitors. There are over 40 different tests and monitors that can be used to diagnose motor and generator winding condition. Therefore, before the individual tests and monitors are discussed, the reasons why testing is done are reviewed and the concepts for selecting which tests and monitoring should be done are discussed. A visual inspection of the winding done by an expert is usually the most powerful tool for assessing the winding condition and determining the root cause of a developing problem. Expert system computer programs attempt to recreate the reasoning processes that an expert uses to interpret test results, as well as other relevant information. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Off-Line Rotor and Stator Winding Tests

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch15
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes the main tests that are commercially available for assessing the condition of rotor and stator windings. It describes the purpose of each test, together with the types of machines and/or windings it is useful for. The chapter describes the theory of the test and compares with other similar tests. Practical information is given on how to apply the test, including the state the winding must be in to do the test and the normal time it takes to do the test. A practical guide is given on interpreting the results which reflects the experience of test users. To aid in test selection, a summary of the most common off-line tests for stator and rotor windings, respectively. Many of the tests are described in IEEE and IEC standards. In addition IEEE Standards 56 and 62.2 give overviews of the tests used for rotating machine windings. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      In-Service Monitoring of Stator and Rotor Windings

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch16
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      The monitors in this chapter measure thermal, chemical, mechanical, and electrical phenomena, and together they can detect most of the important stator and rotor winding failure processes that are likely to occur. The chapter reviews how to make better use of the existing temperature monitors in motors and generators, to extract diagnostic information. Other online temperature monitoring such as infrared thermography is also discussed. Condition monitors, sometimes also called core monitors, are essentially smoke detectors. As they are applied to large hydrogen-cooled generators, they are called generator condition monitors (GCMs). Ozone, or O3, is a gas that is a by-product of partial discharge (PD) in air. Stator endwinding vibration is an important cause of failure in two- and four-pole machines, and it is a very important failure mechanism in large turbine generators. Periodic bearing vibration monitoring is common on most important rotating machines. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Core Testing

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch17
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes the main tests that are commercially available for assessing rotor and stator core tightness and stator core insulation condition. All of the conventional forms of these tests require the motor or generator to be taken out of service. The tests covered are: 1) knife test; 2) rated flux test; 3) core loss test; 4) low flux (El-CID) test. For each test, the purpose is described, as well as the types of machines it is useful for. The theory of the test and its advantages and disadvantages are also covered. Finally, practical guidelines on performing the test and interpreting the results are given. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      New Machine Winding and Rewind Specifications

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch18
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      One of the most important factors to achieve long rotor and stator winding life is the purchase specification of the machine, or in the case of an older machine, the specification of the rewind. This chapter focuses on what could also be considered for inclusion in a purchase specification to achieve the desired life and reliability. Technical specifications for new stator and rotor windings and for the refurbishment/repair of existing stator and rotor windings should have some basic content other than technical requirements. The specific requirements that could be included in a technical specification for a new form-wound stator winding rated 3.3 kV and above, which should give assurance of reliable service over the required life is discussed in the chapter. It talks about the possible requirements for inclusion in technical specifications for new and replacement round rotor and salient pole rotor windings. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Acceptance and Site Testing of New Windings

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch19
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter describes the main tests that are available for prequalifying manufacturer's insulation systems and assessing the quality of insulation in new windings, both in the manufacturer's plant and on-site. All of these tests are designed to help give assurance that stator and rotor windings in new machines and new replacement windings will give reliable service. For stator winding insulation systems rated at 3 kV and above, it is important to gain some assurance that an insulation system provided by the manufacturer will give a long life. The chapter deals with appropriate factory and on-site tests for all insulated rotor windings. It also covers tests for specific types of windings. It provides details on when the tests should be performed and how easy it is to perform them on-site. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Maintenance Strategies

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.ch20
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      This chapter discusses results of visual inspections, can be applied to maintenance strategies to assess the insulation condition in any particular rotating machine. It first provides a review of the maintenance strategies possible. The chapter then presents guidelines on procedures to assess the insulation and indicate the relative condition of any particular machine. The extent of an inspection and maintenance program should be geared to a machine's application, consequences of failure, redundancy, complexity, and value. The inspection and maintenance options are as follows, and, in practice, a cost-effective strategy for an entire plant would contain a mixture of these options: breakdown or corrective maintenance, time-based or preventative maintenance and condition-based maintenance. The chapter also discusses turbogenerators, salient pole generators and motors and squirrel cage and wound-rotor induction motors. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Appendix A: Insulation Material Tables

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.app1
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      No abstract. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Appendix B: Insulation System Tables

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.app2
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      No abstract. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      Index

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.index
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      No abstract. View full abstract»

    • Full text access may be available. Click article title to sign in or learn about subscription options.

      IEEE Press Series on Power Engineering

      Stone, G. ; Culbert, I. ; Boulter, E. ; Dhirani, H.
      Electrical Insulation for Rotating Machines:Design, Evaluation, Aging, Testing, and Repair

      DOI: 10.1002/9781118886663.scard
      Copyright Year: 2014

      Wiley-IEEE Press eBook Chapters

      No abstract. View full abstract»