Detailed analysis of the technology of planar transformers in switching power supplies
Detailed analysis of the technology of planar transformers in switching power supplies
The design of magnetic components is an important part of switching power supplies, and because planar transformers have great advantages in improving the characteristics of switching power supplies, they have been widely used in recent years.
For an ideal transformer, the flux generated by the primary coil passes through the secondary coil, i.e., there is no leakage flux.
For an ordinary transformer, the flux generated by the primary coil does not pass through the secondary coil, thus creating a leakage inductance, and the tight electromagnetic coupling requirement cannot be met.
In contrast, a planar transformer has only one turn of mesh secondary winding, and this turn winding is also different from the traditional enameled wire, but a piece of copper skin, which is pasted and wound on the surface of multiple stamped ferrite cores of the same size. Therefore, the output voltage of the planar transformer depends on the number of cores, and the output current of the planar transformer can be expanded by parallel connection to meet the design requirements
. Therefore, the characteristics of the planar transformer are obvious: the tight coupling of the planar windings makes the leakage inductance greatly reduced; the special structure of the planar transformer makes its height very low, which makes the idea of making the converter on one board come true. However, the planar structure has problems such as high capacitive effects, which greatly limit its large-scale use, although these disadvantages may be converted into an advantage in some applications.
In addition, the planar core structure increases the heat dissipation area and facilitates transformer heat dissipation.
BON
Contact Us
0755-26064466
13424154652
