In single-phase voltage transformer 6 to 10 kV mainly be applicable molded insulation. Cast resin transformers in whole or in part (one winding) are filled insulating compound (epoxy resin). These transformers are intended for indoor use, compares favorably to the oil: have smaller mass and dimensions, and almost maintenance-free operation. Three-phase double voltage transformers have the usual trehsterzhnevye magnetic circuits, and triple-wound – Single-armor. Three-phase winding transformer is a group of three single-phase single-pole units, the windings are connected to the respective scheme. Three-phase winding voltage transformers in the old series (until 1968-1969).
Bronesterzhnevye have magnetic cores. Three-phase transformer less weight and dimensions than the group of three single-phase transformers. If you are working three-phase transformer for a reserve is necessary to have another transformer at full capacity in oil-immersed transformers main insulating and cooling medium is transformer oil. Transformer oil is composed of a magnetic circuit, windings, tank, lid with vvodami.Magnitoprovod collect isolated from each other (for reduce losses to eddy currents) cold-rolled electrical steel sheets. The windings are made of copper or aluminum wire. To regulate the voltage HV winding has branches that connect to switch. In transformers are two kinds of switching branches: load – LTC (load control) and no-load, after disconnecting the transformer from the network – WSP (without switching the excitation). The most common method of second voltage regulation as the most simple. In addition to these oil-cooled transformers (TM) vypuskayutsyatransformatory in hermetically sealed (TMG), in which the oil is not communicates with the air and, therefore, excluded its rapid oxidation and hydration.