By Topic

Power Apparatus and Systems, IEEE Transactions on

Issue 8 • Date Aug. 1965

Filter Results

Displaying Results 1 - 13 of 13
  • Ultrasonic Corona Detection in Transformers

    Publication Year: 1965 , Page(s): 647 - 651
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2638 KB)  

    Corona detection in liquid-filled transformers is becoming recognized as a significant means of ascertaining the integrity of the insulation system. One shortcoming of detectors previously used was their limitation in indicating only the presence or absence of corona without regard to physical location. Techniques have been developed now to utilize the grossly different travel times of the electrical and pressure signals produced by a corona discharge to determine the location of the source. The high-frequency electrical signal arrives at the transformer terminals instantaneously and triggers the oscilloscope sweep. Pressure waves, traveling at much slower speeds through the insulation, arrive at the transducer and are converted to electric signals, which are displayed as the vertical deflection on the oscilloscope screen. The time interval between the start of the oscilloscope sweep and the first vertical deflection is a measure of the distance between the corona source and pressure transducer. Triangulation procedures may be required to discern the exact location of the corona source. These procedures may be used during factory insulation tests or on transformers operating in the field. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Transformer Corona Measurement Using Condenser Bushing Tap and Resonant Measuring Circuits

    Publication Year: 1965 , Page(s): 652 - 657
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1238 KB)  

    Analysis of resonant measuring circuits is given for measurement of corona in transformers, using a bushing capacitor tap connection and a narrow frequency band corona meter. The use of the bushing tap connection and an induced test voltage simplify the test setup. They eliminate the need for corona-free high-voltage connections and for the high-voltage coupling capacitor. Furthermore, in most cases it permits corona testing without the facilities of a shielded room. The use of the resonant measuring circuit greatly improves the sensitivity of corona measurement when the bushing tap connection is used. The circuit may be readily calibrated to render the same numerical values of corona microvolts as the standard National Electrical Manufacturing Association test, yet with a greatly simplified test setup. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Simulated Service Aging Tests of Insulating Oils in Transformers

    Publication Year: 1965 , Page(s): 657 - 666
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (4519 KB)  

    Five different oxidation-inhibited oils and one non-inhibited oil were subjected to more than ten years of simulated service aging tests in 10-kVA transformers. The oils were aged in six conservator-type and four sealed gas-blanketed transformers. The purpose of these studies was to determine the performance of these oils in oxidation-protected transformers. All the oils remained serviceable throughout the 10-year aging period, but showed marked differences in quality in the final test period during which six of the transformers were opened and operated as free-breathing transformers. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Corona Measurement on High-Voltage Apparatus Using the Bushing Capacitance Tap

    Publication Year: 1965 , Page(s): 667 - 671
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1001 KB)  

    A method of corona measurement on high-voltage apparatus which uses the capacitance tap of the entrance bushing as a coupling element is described. The advantage of this method is that it produces a 1-to-1 calibration ratio for most cases by the use of compensating elements at the measuring frequency. Since the high-voltage coupling capacitor is eliminated, the test circuitry is simplified, and the time and effort normally required for this type of measurement is reduced. Theoretical and factual data are given to support the use of this method as an alternative to NEMA Standard Publication 107, 1940 and 1964. View full abstract»

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

    Publication Year: 1965 , Page(s): 671 - 684
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3708 KB)  

    To obtain fundamental information concerning distribution transformer load characteristics, a major study was undertaken by the General Electric Company, together with 55 electric utility companies. Monthly readings of load data were obtained in the field, using especially designed test kits installed at distribution transformers serving predominantly residential loads. Significant results, in terms of national average annual data, are summarized in percentages as: power factor, 92.5; load factor, 26.6; loss factor, 10.5; and peak load, 13.2. Load and loss factors are lower than previously estimated; power factors are higher. Values of the standard deviation associated with each of the averages were calculated. It is significant that, for the first time, a degree-of-uncertainty factor associated with load characteristics and with calculations based on load characteristics has been identified on the basis of statistical analysis. The information derived should be useful to the electric industry because it provides greater knowledge of the most fundamental component of the electric system, i.e., the load itself. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Leakage Reactance of Ring-Type Transformer with Rectangular Core Section

    Publication Year: 1965 , Page(s): 684 - 691
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1090 KB)  

    The ring-type transformer (or reactor) built with an iron core of rectangular cross-sectional area is, by a very considerable margin, the most widely used ring-type electromagnetic device because of its simplicity. An exact formula is derived for computing its leakage reactance. Computation can easily be carried out by an IBM 1620 digital computer. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A New Static Magnetic Constant-Current Transformer

    Publication Year: 1965 , Page(s): 691 - 699
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2739 KB)  

    A new static magnetic constant-current device is described. Its output may be ac or dc, according to connection. Very good results have benn obtained for various loads. Experimental results are given. The performance of dc and ac motors with this devices is described. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Five Years' Experience with Transformer Total Combustible Gas Fault Detector Tests

    Publication Year: 1965 , Page(s): 700 - 706
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2528 KB)  

    Results of incipient fault tests of several thousand power transformers are described. The tests were made with the first practical method and a new instrument for measuring total combustible gas (TCG) in the gas space above the oil in transformers. Useful up-to-date information is presented on instrument sensitivity and calibration, effect of gas contaminants, reading reproducibility, sampling methods, classification and interpretation of TCG readinigs, and comparison of the TCG method with separate analysis of gas components. A tabular report of a field survey of TCG tests on transformers is made. A comprehensive bibliography is given. Recent data on application of the method to vented or free-breathing transformers are also presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Power Transformers and Corona Testing

    Publication Year: 1965 , Page(s): 707 - 714
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3578 KB)  

    There is an increased interest among transformer users in radio influence voltage measurements during routine commercial testing. This paper describes a procedure for determining the presence of corona under oil for transformers. An oscillographic record taken in conjunction with conventional radio influence voltage tests distinguishes between corona in oil which causes progressive deterioration of insulation and corona in air which does not. The data also shows that for high-voltage transformers, the transformer bushing with its capacitance tap provides a suitable coupling capacitor for radio influence voltage tests. View full abstract»

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

    Publication Year: 1965 , Page(s): 714 - 724
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2711 KB)  

    An economic overhead electric power transmission system which produces no radio influence is beyond the present state of the art. However, sound engineering and attention to relevant aspects of design can produce a system having an acceptable (or tolerable) influence level. Such criteria as have been proved by research or experience together with accepted practices in instrumentation and measurement of radio influence fields are presented as an aid in planning extra-high-voltage lines. Because of the many variables and parameters that influence radio noise from power lines, and because the level of a line varies with location and time, it is not presently possible to submit specific desigin criteria. Revisions in thinking in some aspects of the problem may be anticipated as operating experience is gained at the new extra-high-voltage levels. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Application of Statistical Methods in the Design and Uprating of Wood-Pole Transmission Lines

    Publication Year: 1965 , Page(s): 725 - 732
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1620 KB)  

    The electrical insulation design of a proposed Northern States Power Company 345-kV wood-pole transmission line was examined, using statistical methods employed in the METIFOR program [1], introduced in 1964. These techniques, when incorporated with other methods of analysis, gave a predicted outage performance evaluation for this new line, which would interconnect Minneapolis-St. Paul, Minn., with Milwaukee, Wis., and Chicago, Ill. The techniques employed also afford a more comprehensive analysis of the performance of existing lines when uprated to a higher voltage class. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Correction [to "Differential Displacement and Dynamic Conductor Strain"]

    Publication Year: 1965 , Page(s): 732
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (189 KB)  

    R.L. Swart, co-author with J.C. Poffenberger of the paper "Differential Displacement and Dynamic Conductor Strain," a discussion of which appeared on pp. 508-513 of the June 1965 issue of these Transactions, has called the following to the attention of the Editor. In regard to Figs. 5 and 6, the captions are in the correct place, but the figures should be interchanged. In Fig. 7, the test tension was 30 percent rather than 15 percent. View full abstract»

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

    Publication Year: 1965 , Page(s): 733 - 735
    Save to Project icon | Request Permissions | PDF file iconPDF (2723 KB)  
    Freely Available from IEEE

Aims & Scope

This Transactions ceased production in 1985. The current retitled publication is IEEE Transactions on Energy Conversion and IEEE Transactions on Power Delivery, and IEEE Transactions on Power Systems.

Full Aims & Scope