Power transformer

dryindustrialflyback

In the industrial sector today switched-mode power supplies are almost exclusively used to feed electrical equipment and facilities; they supply one or more output direct currents. The fundamental differences are in the type of converter principle. In most cases one of the three switching modes flyback transformer (up to approx. 500 W), single-ended forward converters (up to approx. 1000 W) or push-pull converter (up to the kW range), is used, depending on the power range. Transformers made of toroidal tape cores based on nanocrystalline "VITROPERM" are recommended for push-pull forward converters. In comparison to ferrites, the much higher induction swing (high Bs) and the low magnetic losses allow the following advantages: lower weight, smaller volume, higher efficiency and an expanded temperature range (up to 120 °C) with negative coefficients. These advantages are all the more pronounced, the higher the power to be transferred. The main areas of application are kilowatt power supplies in traction (battery chargers and on-board converters, 25 … 200 kW, insulation voltages up to 14 kV) and in nearly all areas of industrial power supplies in the kW range, where IGBT technology is increasingly being used. The use of stackable toroidal tape cores with HF litz wires in conjunction with cylindrical cast housings of variable height enables easy-assembly large transformers at interesting prices. Aluminium housings ensure a good heat transfer.