Science and Technology
M.K. Kamensky, Cand. Sc. (Engineering), Deputy Division Director;
A.A. Kryuchkov, Cand. Sc. (Chemistry), Bedding researcher;
D.V. Savin, Junior researcher;
T.A. Stepanova, Researcher;
G.A. Troitskaya, Researcher;
A.A. Frik, Team Manager;
M.Yu. Shuvalov, Dr. Sc. (Engineering), Division Director;
Mathematical simulation and experimental investigation of the processes developing during burning of halogen-free polymer compounds used in flame retardant cable constructions
The paper describes the mathematical model of physical and chemical processes taking place in the noncharring polymer material exposed to fire, taking into consideration non-stationary heating of the material by burning gases and its thermal decomposition (pyrolysis) followed by the specimen mass reduction and thickness variation. Experimental determination of parameters required for the model implementation (activation energy, rate constant for two pyrolysis stages, thermal effect) was carried out using thermal analysis methods. The model was evaluated by comparison of the simulation data with the results of measurement by thermal analysis and cone calorimetry methods. The comparison confirmed that the 1st generation model provides an acceptable fit with the experimental data.
Halogen-free compound, burning, pyrolysis, mathematical model
A.V. Korzhov, Cand. Sc. (Engineering), Associate Professor of Electric Power Plant, Grid and System Department; South-Ural State University (National Research University)
Investigation of the influence of the electromagnetic field magnetic component on the rate of partial discharges in cables with paper impregnated and polyethylene insulation
Electric and magnetic field patterns of a 6 (10) kV cable under different loads were simulated with the use of ANSYS program in order to estimate the influence of the magnetic component of the cable electromagnetic field on the processes developing in the insulation. Tests were carried out on the operating paper impregnated cable lines and on the developed experimental assembly with cross-linked polyethylene insulated cable. The investigation results demonstrated the dependences of the partial discharge rates on the alternating magnetic field induction value.
In the course of statistical treatment of the obtained data the following hypothesis was proved: the experimental results of the change in partial discharge rate increment with each value of the magnetic field induction obey the Gauss distribution law.
Partial discharges, magnetic field, electric field, laminated insulation models
E.V. Bykov, Cand. Sc. (Physics and Mathematics), Technical Director; ZAO “Electroneftemash”
Cable as a random process. Strength assessment
The paper discusses statistical aspects of the cable product strength and its dependence on length.
Margin of safety, cable, aging treatment, statistics, analysis, reliability function
Jorma Leppanen, Maillefer
Additional cross-linking to enhance the speed of catenary vulcanization lines – a patented method
The paper is based on the results obtained in the Hellenic Cable plant. The preheating tests were carried out on the EPL 50 catenary continuous vulcanization line delivered by Maillefer in 2008 for the production of medium, high and extra high voltage cables. The tests were aimed at increasing the overall line speed by way of accelerating the vulcanization of the semiconducting layer using additional preheating of the conductor.
Power cable, CCV line, cross-linking, vulcanization