THE ABSORPTION CHARACTERISTICS OF THE PHASE AND ZONE PAPER-IMPREGNATED INSULATION OF POWER CABLE AT DIRECT VOLTAGE
Journal Title: Електротехніка і Електромеханіка - Year 2015, Vol 0, Issue 5
Abstract
Introduction. The moral and physical deterioration of medium voltage power cables with phase and zone paper-impregnated insulation requires implementation of quality systems and reliable nondestructive electric diagnostic. Informative indicator of the insulation is the time decay curve of the charging current. It reflects the processes of accumulation of space charges (absorption). The measurements are carried out the 15th since the second direct voltage supply, then – on the 30th and the second on the 60th second. The ratio of the parameters measured in these times gives the dimensionless criteria – absorption coefficients. Three measurements are made at different times, provide a more complete picture of the state of insulation than the measurement of the value of steady leakage (conduction-through), adopted in conventional prevention trials. Purpose. Research and testing methods of diagnostics of power cables with paper-impregnated insulation by absorption and phase characteristics of the belt insulation based on the total measurements. Methodology. A procedure for determining the individual characteristics of phase and zone paper-impregnated insulation based realized on the use of the equivalent circuit of a three-core cable in the metal shell and solved of an over determined system of linear algebraic equations by least squares. Results. The proposed method allows determining the absorption characteristics of the individual phase and zone insulation medium voltage power cables in the overall metal shell at a direct voltage. Individual characteristics reflect the characteristics of cables and allow a greater degree to assess the degree of aging of each of the components of paper-impregnated insulation. Originality. Regardless of the cable connection diagrams probing electric field grabs as the phase, and zone insulation. The cumulative nature of the measurement leads to the fact that the differences in the properties of insulation components are smoothed: the aggregate results of the measurements do not differ for the different schemes of the same type. The individual characteristics of isolation, defined on the basis of the proposed method are more differences than total, indicating that non-symmetrical modes of operation of the cable. Practical value. The values of individual characteristics power cables 6 kV are 3 times more total, because of what their direct measurement may be a problem. The total resistance of several insulation spaces connected in parallel, behind the individual. Smaller values of insulation resistance are measured more easily, especially on short samples cables.
Authors and Affiliations
G. V. Bezprozvannych, E. S. Moskvitin, A. G. Kyessaeyv
Keywords
Related Articles
- EP ID EP298271
- DOI 10.20998/2074-272X.2015.5.09
- Views 82
- Downloads 0
DETERMINATION OF THE RATIONAL GEOMETRICAL PARAMETERS OF PLATE TYPE ELEMENTS OF MAGNETIC MATRIX OF THE POLYGRADIENT SEPARATOR
DETERMINATION OF THE RATIONAL GEOMETRICAL PARAMETERS OF PLATE TYPE ELEMENTS OF MAGNETIC MATRIX OF THE POLYGRADIENT SEPARATOR
A TECHNIQUE OF EXPERIMENTAL INVESTIGATIONS OF LINEAR IMPULSE ELECTROMECHANICAL CONVERTERS
Purpose. Development of a technique of experimental studies linear pulse electromechanical converters parameters, which are used as shock-power devices and electromechanical accelerators, and comparing the experimental r...
A CHOICE OF SECTIONS OF ELECTRIC WIRES AND CABLES IN CIRCUITS OF DEVICES OF HIGH-VOLTAGE HIGH-CURRENT IMPULSE TECHNIQUE
Purpose. Implementation of calculation choice of sections of electric wires and cables in circuits of devices of high-voltage high-current impulse technique (HHIT), characterized flowing of pulsed current ip(t) with diff...
ESTIMATING THE LIMIT POSSIBILITIES OF THE STEP CHARGING SYSTEM FOR CAPACITIVE ENERGY STORAGE
The aim of the article is to estimate the limit possibilities of step-by-step charging the capacitive energy storage which are caused by the achievement of a balance among the processes of the receiving and losing of ele...
EXPERIMENTAL APPROBATION OF AN ELECTRODYNAMIC DIRECT ELECTRIC SYSTEM FOR EXTERNAL AUTOMOBILE BODY REPAIR
The article presents results of experimental research on an electrodynamic system with direct current flow for external automobile body repair. A possibility of specifying the direction of increasing magnetic pulse attra...