How to properly maintain transformers: basic operation rules and safety measures
Operation of Transformer Equipment
The main structural elements of oil-filled transformer installations and automatic transformers are: magnetic cores, windings with taps and insulation components, a tank with a diverter switch. In addition, transformer units are equipped with various auxiliary systems: cooling systems, tap changers, oil protection against environmental influences, monitoring systems, etc., as well as bushings.
The magnetic core of a compact transformer substation (CTS) or a transformer performs the function of a magnetic circuit and serves as its structural and operational base. In the magnetic core construction, a functional part that conducts magnetic flux is distinguished from a non-functional part, which provides mechanical strength and serves as a base for mounting and fixing various components. The active parts of older transformers were made from hot-rolled silicon-electrical steel grades 1511, 1512, 1513.
Modern transformer units use cold-rolled electrical steel grades 3413 and 3416, which have reduced core losses and high permeability. This allows higher magnetic induction and reduces both power losses and electrical current. To minimize eddy current losses, the steel sheets (typically 0.35–0.5 mm thick) are separated by fire-resistant elements, lacquer coatings, or both.
The thickness of insulation coatings on electrical steel is now 4–5 microns, compared to 20–30 microns in the past when paper tapes were used for lamination. The magnetic core structure consists of vertical stacks clamped from top and bottom. During assembly, steel sheets are stacked so that the joints of one layer are overlapped by the sheets of the next. In cold-rolled steel cores, angled sheet edges are used instead of square ones. This skewed stacking reduces magnetic losses in the corners of the core, as it shortens the path of magnetic flux that does not align with the steel rolling direction.
You can buy transformers and CTS units in Moscow from dozens of companies, but we recommend purchasing complex technical equipment only from licensed companies that provide proper installation training and support.