Hello guys. First time in this forum.

I have simple question.
I am building 3 Axis CNC Stepper Drive/motor.
Current is about 5A each so total of 15A.
I am using 3Phrase transformer 220V as a way to filter the main power (220V, 3P, 3KW = $150-200)

I have never use other Filter before, but I think it would be a lot cheaper?
More compact? Any advice which one to choose from? And is there downside compare to isolated transformer that I use?
Thank you
Jeff