scholarly journals Destruction of polymer insulation and threshold amplitudes of current pulses of different temporal shapes for electric wires and cables in the low- and high-current circuits of pulse power engineering, electrical engineering and electronic devices

Author(s):  
M.I. Baranov ◽  
S.G. Buriakovskyi ◽  
V.V. Kniaziev

Goal. Development of engineering method for settlement of threshold amplitudes Impk of single-pulse current ip(t) of different temporal shapes for electric wires and cables with polyethylene (PET), polyvinylchloride (PVC) and rubber (R) half-length insulation, used in modern pulsed power engineering, electrical engineering and electronics in their low- and high-current circuits. Methodology. Basis of the theoretical and applied electrical engineering, electrical power engineering, electrophysics bases of technique of high-voltage and large pulsed currents, bases of low- and high-current electronics, measuring technique, electromagnetic compatibility and standardization. Results. Development of engineering method is executed on close calculation determination of threshold amplitudes Impk of single-pulse axial-flow current ip(t) of different temporal shapes for electric wires and cables with copper (aluminum) current-carrying parts and PET, PVC and R half-length insulation, used in the ow- and high-current circuits of pulsed electrical power engineering, electrical engineering and electronics. Electrothermal resistibility of half-length insulation of the examined cable and wire products (CWP), proper maximum to the possible temperatures of heating of current-carrying and insulating parts of the probed wires and cables and shutting out the offensive of the phenomenon destruction in the indicated insulation of CWP, was fixed based on this method. Calculation analytical correlations are obtained for finding in probed CWP of threshold numeral values of Impk amplitudes of pulses of current ip(t), time-varying both on aperiodic dependence of type τf/τp with duration of their front τf and duration of their pulses τp and by law of exponential attenuation sinewave. It is shown that at Imp>Impk destruction of their half-length insulation, resulting in the decline of service life of CWP, will come from the thermal overheat of current-carrying parts of the examined electric wires and cables. The examples of practical application of the offered method are resulted upon settlement for a radiofrequency coaxial cable RC 50-4-11 with middle sizes is easily soiled with continuous PET insulation of threshold amplitudes of Impk of standard aperiodic pulses of current ip(t) from nano-, micro- and millisecond temporal ranges of shape of τf/τp=5 ns/200 ns, τf/τp=10 μs/350 μs and τf/τp=7 ms/160 ms. It is shown that with the proper growth of parameter τp>>τf for flow on a continuous copper tendon and split copper shell of radiofrequency coaxial cable RC 50-4-11 with middle sizes is easily soiled indicated homopolar pulses of current ip(t) substantial diminishing of their threshold amplitudes of Impk (with 531,2 кА for the nanosecond pulse of current of type 5 ns/200 ns to 1.84 кА for the millisecond impulse of current of type of 7 ms/160 ms takes place). Originality. An engineering method is first developed for close settlement of threshold numeral values of Impk amplitudes of single-pulse axial-flow current ip(t) of arbitrary peak-temporal parameters for electric wires and cables with copper (aluminum) current-carrying parts and PET, PVC and R half-length insulation. Practical value. Application in electrical engineering practice of the offered engineering method for determination of threshold amplitudes Impk of the indicated pulses of axial-flow current ip(t) for the probed electric wires and cables will allow considerably to increase service life of examined CWP.

2019 ◽  
Vol 73 (5) ◽  
pp. 161-173
Author(s):  
Viktor V. Oliynyk ◽  
Olekandr M. Samoylenko ◽  
Ilona V. Batsurovska ◽  
Nataliia A. Dotsenko ◽  
Olena A. Gorbenko

The article presents an experimental model of training future engineers in specialty“Electric Power Engineering, Electrical Engineering and Electromechanics”in conditions of massive open online courses (MOOC). The article reveals the concepts of modeling, designing and validity in pedagogy. The stages of construction of the pedagogical model are presented. Four blocks of the model of training the students in specialty”Electric Power Engineering, Electrical Engineering and Electromechanics”for educational and scientific activities in the conditions of MOOC are presented: motivational, content and procedural, technological and productive. The motivational block is characterized by the definition of the main goals of the introduction of pedagogical technology: the preparation of a highly qualified specialist. The content and procedural block is based on the implementation of pedagogical conditions of educational and scientific training. The technological block consists of three stages: motivational, cognitive-procedural and control-evaluation. The productive block provides monitoring of educational and scientific training of students in the specialty "Electrical power, electrical engineering and electromechanics".It is determined that there is feedback between all blocks of the model, which allows to make changes in the content, forms and methods of teaching. The principles of construction and the main structural elements of each of the blocks are analyzed. The general principles for the training of future engineers in specialty ‘Electric Power Engineering, Electrical Engineering and Electromechanics” are determined in conditions of MOOC; forms, methods and means of instruction are described. It is considered that educational and scientific training is implemented through such forms of teaching as lectures, video lectures, webinars, workshops, video conferences, discussion in forums, participation in scientific conferences and seminars. It is determined that the result of the developed model is readiness of the students majoring in ‘Electric Power Engineering, Electrical Engineering and Electromechanics” for research and study.


1993 ◽  
Vol 209 (1-3) ◽  
pp. 291-294 ◽  
Author(s):  
G.O. Zimmerman ◽  
Y.Z. Negm ◽  
M.Z. Tahar ◽  
S. Buczkowski ◽  
R.E. Powers ◽  
...  

1987 ◽  
Vol 33 (3) ◽  
pp. 206
Author(s):  
J.F. Gamlin

Author(s):  
V. V. Arutyunov

The paper analyzes the importance of power engineering for solving a wide range of practical problems. The purpose of this study is to evaluate the results of the research of scientists and specialists in 2013–2019 in power engineering, electrical engineering, electronics and radio engineering on the basis of RSCI databases (Russian Science Citation Index). The analysis was carried out taking into account a number of scientometric indicators: the publication activity of researchers – the annual number of their publications, as well as the citation of these publications and the demand for the results of their work. Features of dynamics of formation of indicators of publication activity are revealed: its high values are typical for electronics and radio engineering and minimum values (more than three times smaller) – for electrical engineering. For all three industries analyzed the number of publications increased in 2013–2018. It is noted that the citation indicators for the three industries have been continuously decreasing since 2014. At the same time, in the field of electronics and radio engineering in 2013–2017, citation rates are three or more times higher than similar indicators for energy and electrical engineering. The results of research in the field of electronics and radio engineering are the most popular, while the results of research in the energy sector are the least popular. At the same time, the annual demand for research results in electronics and radio engineering exceeds similar indicators for energy by about 1.4 times. The low demand indicators for all areas of research in 2019 are obviously due to the same reason as for small citation indicators this year: the slow “response” of the scientific community to this year's publications.


Sign in / Sign up

Export Citation Format

Share Document