Diagnostic of power transformers are in service long time
Journal Title: Вісник Національного технічного університету "ХПІ". Серія: Проблеми удосконалювання електричних машин і апаратів. Теорія і практика - Year 2018, Vol 32, Issue 1308
Abstract
Purpose. Improvement of power transformer condition diagnostic being in service long time. Methodology. The theoretical aspects of the paper are based on theory fundamental statements of electrical apparatus and material engineering. Experimental investigations were real-ized by monitoring data incisive analysis of capacitor (С) and approximate power factor (tgδ) of autotransformer bushing 550 kV on operating equipment. Results. Results and observational analysis are given. They show that power transformer diagnostic recommended methods in operation do not be able to in full detect defects with accumulative character appearing during a continuous exploitation peri-od. Originality. In addition to the existing methods of power transformers diagnostic to use a technique based on the registration of par-tial discharges is proposed. It allows detecting insulation defects at early stages of development. Due to the fact that current value of parti-cle discharges is not large especially in the initial stages, it make sense for studding of partial discharges in transformer insulation to fix electrical field and acoustic signals generating partial discharges. Practical value. Practical value for electrotechnical branch is improve-ment diagnostic and enhancement of safety of substation equipments exploitation.
Authors and Affiliations
O. G. Volkova, L. B. Zhorniak, I. V. Lyevyenkov
Multiphysical model calculation of boundary current welding contact vacuum circuit breakers
A multiphysical model of alteration of the strength bodies’ contact area as a function of the contact surface temperature is considered. Mathematical formulation of the problem is described, an example of the welding sus...
Requirements for contact materials of switching devices
It is proposed to move from use in the construction of high-current electrical apparatus of copper alloys as electrical contact materials to powder materials. An analysis of the composition of the powder material is pres...
To the question of improving the quality of internal insulation of high-voltage measurement transformers
In this paper, the issues of increasing the reliability of electrical insulation of high-voltage measuring transformers, which are in operation in various power supply systems, and methods for increasing the service life...
Use of diagnostic data of the main drives of the rolling mills in automatic measurement systems of products length measurement
The study of measuring system was carried out in rolling shop. The complex was proposed based on a mathematical model of the rolling process and 650 mill diagnostic data. The paper describes mathematical modeling of a co...
The calculation of the motion of charged particles in crossed fields
The results of the calculation of the motion of charged particles in crossed electric and magnetic fields in particle approximation are shown. The parameters of magnetic and electric fields of installation for charged pa...