Stuff about VFDs and motors

[DIYSwede]

-Good grief, Tony!
A diy-ed 3P yoke LC filter! Excellent approach.
Nice, straight-forward write-up very much appreciated at this receiving end!
Did you mention the cap values - I was a bit eager in reading it...

Is the transformer whine from inter-layer movement in the core laminations?
You could perhaps dunk the whole shebang in varnish?

Keep up the good work, and I'll be somewhat more patient in the future!

Tip: For designing filters, there's a bunch of RF designs that could be applicable even at these freqs:
Search "Butterworth LC filter design" or peek at this random find:
https://rf-tools.com/lc-filter/

ATB
Johan