Dry and resin transformers
Description
ELETRAFO builds, repairs and modifies M.T. and b.t. from the power of 160 KVA to 2.5 MVA and a maximum operating voltage of 24KV.
The magnetic circuit is made with silicon sheet with low loss 45 ° oriented crystals in order to minimize noise AND LEAKS
The ditching system of the pack is sized in such a way as to resist the electrodynamic stresses of the windings in the event of a short circuit.
The windings of M.T. they are made with aluminum or copper tape or wire insulated with interwound polyester film. The thermal expansion coefficient of aluminum, close to that of resin, allows the structure to respond homogeneously to temperature variations due to frequent load changes, thus avoiding dangerous stresses that would damage the transformer over time. The different nuts of the medium voltage winding are stacked and connected in series to each other to form a phase coil which is subsequently ENCLOSED IN RESIN. IT IS SUBSEQUENTLY TESTED TO CHECK the insulation and the absence of partial discharges.
The low voltage windings are normally made of aluminum or copper sheet insulated with materials in class F or H.
They are protected by class H oven-dried paint which forms a compact mass resistant to radial short-circuit stresses to obtain with a reduced percentage of additional losses. The axial stresses are very low thanks to the conductor in a single sheet.