Cores for 400Hz sine inverters.

[dick_freebird]

An interesting article on this subject hit my inbox today:

**broken link removed**

It appears that a 50/60Hz transformer is usable at higher
frequency, and then at a higher voltage than rated. The
downside is losses (winding resistance and eddy current).

Good collection of basic formulae in the article.

 

[FvM]

At first sight, the formulas are applicable to the discussed problem. Looking into it more thoroughly, it seems like the author doesn't understand his own formulas and jumps into conclusions.

According to my literature, the exponents in the core loss equation
P = k * f^m * B^n
can be ususally ordered like this 1 < m < n < 2.

This means, that the utilizable power increases with frequency, but possibly not very much. To get full advantage of the high Bmax of silicon iron and iron alloy cores at higher frequency, you need to refer to special low loss alloys.

 

[ALERTLINKS]

Some relevant links.

**broken link removed**
https://users.encs.concordia.ca/~pillay/c28.pdf
https://nipponcore.en.alibaba.com/product/405873538-211855049/400HZ_transformer_core.html
https://nipponcore.en.alibaba.com/product/401190489-211985083/400Hz_transformer_core.html