LCS701 - transformer is too hot
Posted by: Jan Stejskal
on
I have got a design with LCS701 for power 160W. PI designer has counted the transformer on core EFD25. PIXLS is attached.The power supply works and switching frequency is 198kHz. I have got a problem with temperature of transformer. Secondary winding has got a temperature 112oC after 15 minutes. Primary winding is hot too. Can you help me with this problem?
Thanks for your time
Files
| Attachment | Size |
|---|---|
| HiperLCS 150W_40_4_efd25_PI.pixls | 43.82 KB |
Hi,
Are you using Litz wire or magnet wire.
In high frequency designs using single strand magnet wire can cause higher winding loss because of higher ac resistance.
K Ratio on your design is 2.4. Generally a lower K ratio can cause higher circulating currents and it can increase winding loss. Try to get Pixls suggested value (Lpri and Lres).
Can you enter the core loss density data from the datasheet of the core that you are using in order to findout what the core loss is?
Please go through the HiperLCS appnote in order to get better understanding to design with PIxls tool.
you can find the app note at following location
http://www.powerint.com/sites/default/files/product-docs/an55.pdf
Could you please send me the transformer document so that I can review the document.
Regards,
PI-NANO