Results 221 to 230 of about 1,020 (264)
Some of the next articles are maybe not open access.
Heat Damage Assessment of Oil Immersed Transformer
Journal of Performance of Constructed Facilities, 2000An outdoor distribution oil immersed transformer on the premises of a factory was exposed to intense heat due to a fire that occurred at a neighboring factory. The licensed electrical worker for the premises where the affected transformer was installed informed his client, the owner, that the affected transformer was subjected to a high-temperature ...
openaire +1 more source
Mechanism of Gas Movement and Convergence in Oil-immersed Transformer
2021 International Conference on Electrical Materials and Power Equipment (ICEMPE), 2021As a transformer main protection, light gas protection responds to transformer failure solely based on the gas volume within its collection chamber. Such single protection criterion failed to reflect the actual transformer working condition accurately, which have led to protection malfunction or refusal-operation and caused several transformer ...
Yucheng Zhang +5 more
openaire +1 more source
Oil-Immersed Power Transformer Overload Calculations by Computer
IEEE Transactions on Power Apparatus and Systems, 1969Application of overload ratings to power transformers is considered in the light of 30 years of operating experience. A comprehensive description is given of the philosophy of overloading, methods of calculation, transformer life curves, and a working computer program which incorporates these factors with increased accuracy and reduced engineering time.
John Blake, Edward Kelly
openaire +1 more source
The Development of an Oil-Immersed Surge Arrester for Distribution Transformers
IEEE Power Engineering Review, 1985The recent development of an oil- immersed, zinc oxide surge arrester meets a need for distribution transformer protection that is immune to environmental factors that frequently cause premature failure of conventional external arresters. This paper describes the design philosophy used to determine the requirements for this device and the tests ...
C. McMillen +3 more
openaire +1 more source
Temperatures produced by overloading oil-immersed transformers
Electrical Engineering, 1944TRANSFORMERS have thermal capacity; furthermore, they frequently show lower temperature rises during test than the guaranteed rise. Load factors are usually under 100 per cent and rarely are ambient temperatures continuously 40 degrees centigrade. For these reasons it usually is possible to get out of them more than is indicated by their name-plate ...
openaire +1 more source
THERMAL ANALYSIS OF LARGE OIL-IMMERSED TRANSFORMER WINDINGS
Electric Machines & Power Systems, 1983ABSTRACT A method of numerical thermal analysis of large oil-immersed transformer windings is presented. The analysis consists of two steps: first, the leakage magnetic field is solved in the windings; second, the basic and additional losses distribution is calculated simultaneously with temperature rise distribution in the cross-sections of individual
V. PREININGEROVA, V. KAHOUN, I. DOLEŽEL
openaire +1 more source
Cooling of Oil-Immersed Transformer Windings after Shut-Down
Transactions of the American Institute of Electrical Engineers, 1917The 1916 A. I. E. E. Rules require that the temperature rise of transformer windings be observed by the resistance method. Since the measurement of resistance usually requires considerable time, there is always a drop in temperature between the instant of shut-down and the time of observing this resistance measurement.
openaire +1 more source
Thermal evaluation and loading of oil-immersed distribution transformers
1971 EIC 10th Electrical Insulation Conference, 1971Manufacturers must continually investigate new materials to stay competitive. Users must load transformers to their thermal limit in order to realize operating economies. The test procedures and loading guides discussed in this paper offer means by which both can affect substantial savings.
openaire +1 more source
Coupled Thermal and Flow Analysis for Oil-immersed Transformers
2006 12th Biennial IEEE Conference on Electromagnetic Field Computation, 2006In this paper, a 3D thermal model that couples thermal and flow fields of a high-power high-frequency oil-immersed transformer was presented. The thermal model including a set of conservation equations was solved using the finite volume method.
openaire +1 more source
Thermal Hydrodynamic Model of Oil-Immersed Power Transformers
Fluids Engineering, 2001Abstract A lower hierarchy model of an oil-immersed – transformer was used to calculate the heat transfer in transformer windings. Contrary to the approach of other investigators, who considered a global network, this approach has the merit of focusing on the main body of the transformer.
openaire +1 more source