By Topic

American Institute of Electrical Engineers, Part II: Applications and Industry, Transactions of the

Issue 4 • Date Sept. 1959

Filter Results

Displaying Results 1 - 14 of 14
  • Evaluation of transient system response

    Page(s): 177 - 186
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2367 KB)  

    FREQUENCY-RESPONSE techniques are among the most powerful tools in the hands of the feedback control systems engineer. Perhaps of greatest use today are the attenuation and phase-angle plot techniques developed by Bode. These techniques are particularly effective in analysis and synthesis of stable systems in establishing the relative stability of a system.1 Although it is possible to estimate the transient response of a system whose open-loop frequency response is known, the accurate prediction of this transient response by analytical means involves obtaining the roots of the characteristic equation for the closed-loop system. Knowing the system's closed-loop factored transfer function, the transient response of the system may then be obtained analytically by means of Laplace transform methods. Thus, if View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Improved D-C high-potential testing of insulation systems in low- and medium-voltage D-C equipment

    Page(s): 186 - 199
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (6889 KB)  

    Elimination of unexpected breakdowns in d-c high-potential testing is made possible by observing the electrical noise caused by ionization. (The terms ionization and ionization discharges are used as common terminology to refer to charge redistributions as a result of gaseous breakdowns in the insulation systems; see Appendix I. However, it will be more appropriate for the purposes of this paper to include in this term the charge redistributions taking place whenever a minute conducting path on the insulation surface is broken down.) The relative severity of ionization discharges is easily detected by picking up a voltage drop proportional to the current in the test circuit. The high-frequency discharges can then be observed on an oscilloscope screen or measured by other means. It is found that: View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A recommended program for resistance-welding instrumentation

    Page(s): 199 - 209
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (9633 KB)  

    THE PROBLEM of developing a practical method of instrumentation for production use at the Westinghouse Electric Corporation has been advanced by the combined interest and efforts of research, development, and manufacturing people within the company. The use of instrumentation for resistance welding involves wide economic considerations in product quality and production costs and has thereby greatly stimulated this interest. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Electrical features of the four corners pipe line

    Page(s): 209 - 223
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (12708 KB)  

    THIS PAPER discusses generally the electric power distribution systems, control schemes, supervisory control, telemetering, and communication means employed on a crude-oil pipe line constructed by The Shell Pipe Line Corporation. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The life expectancy of class a random-wound motor insulation as determined by AIEE standard no. 510 test procedure

    Page(s): 224 - 228
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1835 KB)  

    TEST PROCEDURES for determining the relative life expectancies of different insulation systems for random-wound machines, using either complete motors or models, called motorettes, are provided for by AIEE no. 510.1 The procedure calls for subjecting the motorettes to successive periods of high temperature in ovens, followed by vibration and exposure to moisture, and an overvoltage check. The cycle is repeated until the test unit fails under voltage. The tests are conducted at three or more temperatures, and are made on a sufficient number of samples to obtain the desired statistical accuracy. The tests on motors are similar, but the heating, vibration, and voltage exposures are all obtained at the same time by operating the motors on a frequent starting or reversing cycle. The results of the tests are given in the form of a life-temperature chart, as in Fig. 1. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A relay-type feedback control system design for random inputs

    Page(s): 228 - 233
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1917 KB)  

    EARLIER literature has suggested the design of the so-called optimum relay control system, where the term ¿optimum¿ is based on the system having the fastest possible response in terms of reducing the error to minimum following a step or ramp input.1¿4 It has been pointed out that these systems are optimum only in this special sense, and that their response to other types of input may be undesirable.5 View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Detector car history and new developments

    Page(s): 233 - 239
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (15101 KB)  

    THE rail detector car is an assemblage of specialized test equipment mounted on self-propelled railroad cars and is used for the detection of all types of defects that develop in railroad rails. The story of detector cars should start a few years before there were any such cars. Before 1926, the railroads were faced with a serious and fast-growing menace to their very life: the breaking of rails. The source of this menace was the transverse fissure, a very thin crack which would start within the rail and develop outwardly until it caused the rail to break. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Aluminum bus for shipboard application

    Page(s): 239 - 247
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (7075 KB)  

    THERE is special interest in aluminum for shipboard use because of the savings realized in weight and because of shortages in copper that occur especially in times of national emergency when shipbuilding is at its peak. Although aluminum has been considered for cable conductors for shipboard use it is generally without over-all advantage because the larger conductor size results in a greater volume and weight of insulating and sheathing materials. These factors involving insulation are not imposed in applying aluminum to electrical bus. In utilizing aluminum bus for switchgear application problems arise that are mostly but not entirely confined to the making of satisfactory electric connections. The literature on the subject contains a large body of information. Much effort is devoted to coping with a particular environmental stress or material property considered to predominate in the reliability of a specific system. Some of the work stresses the advantage of a proprietary material or a particular method. Instances of controversy are attributed largely to differences of conditions of evaluation and as such appear best capable of resolution by re-evaluation on the same basis. The rather extreme conditions and their wide variety in shipboard service justify additional evaluation. A comprehensive experimental investigation was therefore carried out to determine the optimum means of utilizing aluminum bus in switchgear with the primary objective of long-term service reliability. Measurements taken on large numbers of specimens determine the extent to which different types of aluminum joined by various bolting methods, and with joint surfaces prepared with various joint compounds, are affected by prolonged load cycling, overload, weathering, vibration, and high impact shock; similarly tested is the extent to which silver platings are affected. Measurements on an actual marine installation after 20 years of service are correlated with the results of experimental labora- ory work. In addition, information is provided which is useful in the design of bus supports needed to withstand fault currents. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Predicting the performance of a wind tunnel regulating system using an analog computer

    Page(s): 248 - 252
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1437 KB)  

    THE USE of an analog computer, particularly one of the electronic differential analyzer type, in the analysis and design of feedback control systems has been well established in the past few years. Quite often, however, a detailed computer investigation of a control system is not necessary. For example, in some instances the control system may contain only a few components which can be represented by linear transfer functions, in which case the familiar methods of linear servomechanism analysis may be employed. It is also possible in some cases that it is just as economical to optimize a design on the test floor without benefit of a computer study. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A new chart relating open-loop and closed-loop frequency responses of linear control systems

    Page(s): 252 - 255
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1283 KB)  

    CONTROL ENGINEERS generally adhere to the use of frequency response as the fundamental tool for feedback control systems. Through the use of the Nichols chart,1 the open-loop characteristics can be quickly converted to the closed-loop characteristics. The performance of control systems can be estimated according to the gain and phase margins and the magnitude of peak M. Although actual performance may be quite different from that predicted by a certain value of a particular specification, yet by means of Meerov's method2 it should not be difficult for engineers to determine the limits of applicability and to evaluate its effectiveness. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Generator insulation systems development for hypersonic aircraft

    Page(s): 255 - 259
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2800 KB)  

    PRESENT and future aircraft requirements for electric power are constantly increasing, with operational requirements of speed, altitude, and equipment imposing greater loads on the electric generating systems. The need therefore exists for generators capable of operating at higher temperatures than those presently available. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Battery impedance: Farads, milliohms, microhenrys

    Page(s): 259 - 262
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1139 KB)  

    THE ELECTRICAL RESISTANCE of storage batteries is important to two groups of people. Designers of telephone equipment need to know the resistance to alternating current in order to evaluate the cross talk between simultaneous telephone conversations which must pass through the central station battery. They must also be able to evaluate the amount of filtering required to remove hum, noise, and switching pulses from the output of the charging and switching equipment. In addition, designers of central power stations need to know the resistance of the battery which must supply short pulses of power to operate electric switches. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The effect of variable high-altitude humidity on the wear of nondusting brushes

    Page(s): 263 - 267
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2642 KB)  

    THE important effect which water vapor has on the performance of carbon brushes has been recognized for many years. Prior to 1935,1 cases of excessively short brush life were found to be due to the low humidity of the cold air of midwestern United States winters. Early in World War II, when bombers began flying at altitudes above 20,000 feet, this low-humidity problem was more spectacularly demonstrated when it was found that the brushes on the dc generators were wearing out completely during flights as short as one hour. Tests in simulated high-altitude atmospheres showed, conclusively, that the extremely rapid wear, or ¿dusting,¿ of carbon brushes was caused by the inability of the brushes to maintain lubricating films on commutators in the extremely low atmospheric humidities which were found to exist at high altitudes. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Development of fuses and terminals for high-temperature applications

    Page(s): 267 - 272
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2022 KB)  

    COMPONENTS TO BE developed under the Hotelec program include fuses, terminals, and splices. The most significant new requirement of this program as it affects these components is the extension of the temperature level to 850 F (degrees Fahrenheit) for terminals and splices, and to 600 F for fuses; these are ambient temperatures with conductor temperatures reaching 1,000 F. Other significant requirements are for the devices to withstand vibration to 20 g (gravitational acceleration) at a frequency of 80 to 2,500 cps (cycles per second); acoustic noise of 150 decibels, as well as shock of 50 g for 11 milliseconds. The altitude of 80,000 feet demands resistance to ozone, and requires consideration of the effects of corona. Similarly, the significant increase of temperature makes it necessary to limit thermal voltages at junctions to 0.1 millivolt. View full abstract»

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

Aims & Scope

This Transaction ceased production in 1963. The current retitled publication is IEEE Transactions on Industry Applications.

Full Aims & Scope