-
Technical analysis of planar transformer in switching power supplyRelease time:2018-4-4 16:10:10
The design of magnetic components is an important part of the switching power supply, because the planar transformer has a great advantage in improving the characteristics of the switching power supply, so it has been widely used in recent years. For an ideal transformer, the flux produced by the primary coil passes through the secondary coil, that is, no leakage flux. For ordinary transformers, the flux generated by the primary coil does not all pass through the secondary coil, thus causing leakage, and the tight requirements of the electromagnetic coupling can not be satisfied. But the plane transformer has only one turn of the reticular secondary winding, which is also different from the traditional enameled wire, but a piece of copper skin, which is attached to the surface of a number of the same size stamped ferrite cores. Therefore, the output voltage of a planar transformer depends on the number of cores, and the output current of the planar transformer can be expanded in parallel to meet the requirements of the design. Therefore, the characteristic of the planar transformer is obvious: the tight coupling of the plane winding makes the leakage sense greatly reduced; the special structure of the plane transformer makes its height very low, which makes the assumption of a converter on a board. However, there are many problems, such as the high capacitive effect of the plane structure, which greatly restrict its large-scale use. However, these shortcomings may also be converted into an advantage in some applications. Besides, the magnetic core structure of the plane increases the heat dissipation area, and is conducive to the heat dissipation of the transformer.