Transformer Laminations Wikipedia

Laminations are provided to reduce eddy currents.

Transformer laminations wikipedia.

Eddy currents are loops of electric current induced within conductors by a changing magnetic field in the conductor due to faraday s law of induction. From initial transformer lamination production in 1927 to serve the infant radio industry thomas skinner s ei transformer lamination operation led the way pioneering large three phase wide window and thin gauge laminations. The insulated laminations minimizes eddy current losses in the iron core. Lamination is the technique process of manufacturing a material in multiple layers so that the composite material achieves improved strength stability sound insulation appearance or other properties from the use of the differing materials such as plastic a laminate is a permanently assembled object created using heat pressure welding or gluing.

High permeability and low distortion 80 and 49 nickel alloy and cobalt iron standard material thickness of 0 35 mm 0 20 mm and 0 15 mm. The insulation materials used in transformer construction varies but are mainly the finish applied to the laminations varnish or coated insulation on the wire paper fish paper crepe paper etc or plastic film for the coil cardboard or plastic for the bobbin and the varnish that the completed transformer is dipped into at the end of construction. Electrical steel is usually manufactured in cold rolled strips less than 2 mm thick. This is the most common type of transformer widely used in electric power transmission and appliances to convert mains voltage to low voltage to power electronic devices.

Electrical steel lamination steel silicon electrical steel silicon steel relay steel transformer steel is an iron alloy tailored to produce specific magnetic properties. They are available in power ratings ranging from mw to mw. Wikipedia defines eddy currents as. Again look at large line frequency power transformers and you will sometimes be able to see a spiral of thin layers instead of parallel flat layers as.

Laminating the core greatly reduces eddy current losses one common design of laminated core is made from interleaved stacks of e shaped steel sheets capped with i shaped pieces leading to its name of e i. Thin laminations are generally used on high frequency transformers with some of very thin steel laminations able to operate up to 10 khz. That s often called a wound core. Now the transformer core looks like a secondary winding but since the ends aren t connected it is always open circuit and therefore not present electrically.