DIAGNOSTICS FACILITY FOR EFFECTIVE CONTROL OF WINDING CONDITION OF HIGH VOLTAGE TRANSFORMERS

Abstract

The importance of the research is driven by the fact that all stages of production and processing of geological resources include a large-scale technological complex, in which the dominant role is played by electric power systems that ensure the operation of all the main components and assemblies. A significant class of high-voltage equipment of such systems is distribution power transformers and shunt reactors. Failure of transformer equipment causes a rapid shutdown of the technological cycle, an emergency and financial losses. This can be avoided by ensuring the reliable operation of electrical equipment by conducting quality diagnostics to assess the residual life of a transformer or reactor. Standard technologies, such as measurements of direct current resistance, absorption coefficient and dielectric loss tangent do not allow detecting a winding defect at an early stage of development, and therefore cannot be considered effective. In almost all world energy systems, the FRA technological complex is considered to be promising and recommended for use, which is a technical implementation of the method of analyzing frequency characteristics. However, this technology encounters difficulties of a technical and organizational nature when implemented in Russian energy systems. The instrument base and software do not always meet the requirements and standards for testing electrical equipment of the grids of the Russian Federation. As a result, there are a high percentage of bad conclusions about the results of monitoring. The issue is complicated due to the fact that the patent for the use of FRA technology belongs to the institutes of the USA, Canada and several European countries. Taking into account the unfriendly political situation, a number of sanctions and restrictions on the export of machinery and technologies, further use of FRA technology may be problematic. Modern technology corresponding to the requirements does not exist in the Russian Federation. In this regard, the development of a reliable diagnostic complex that takes into account the technical, climatic and other features of the electric power systems of the Russian Federation and allows effective monitoring of the state of the windings taking into account the specifics of domestic transformer equipment is an urgent task. The main goal of the work is to research the effectiveness of the diagnostic complex based on probing pulses of nanosecond duration on real transformer equipment. To conduct a comparative analysis of the results, monitoring the status of the transformer windings of the developed complex and the FRA technological complex. Object of the research is real transformer TM-160/10, fails such as short-circuited turns and mechanical displacement of the windings were created. Methods: experimental measurements of probing pulses and response in both technologies – pulsed and FRA. Comparison of condition control efficiency for both methods. Using Tektronix electronic oscilloscopes of the TDS-1012 type, a probe and a response pulse were recorded. The measurements were carried out for the same defective states of the winding using the FRA complex. Results. On a real transformer, the efficiency of the developed diagnostic complex for monitoring the status of transformer windings based on nanosecond probe pulses was experimentally studied. It is shown that the efficiency of monitoring the status of transformer windings with the help of the developed complex is no worse, and in some cases exceeds the efficiency of the FRA complex.

Keywords

• winding condition control
• pulsed method
• probing impulse
• winding fail
• control efficiency