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The answer to this question is a very “qualified” yes.

We have built such filters and they are not particularly economical or efficient. The problem with designing a filter for a system to meet CE101 is the low frequency of the noise signals involved.  Typically, the 3rd , 5th and 7th harmonics are the problem frequencies.  This means that for 60 Hz power the filter must attenuate 180, 300.and 420 Hz at a minimum.  In the case of 400 Hz power, attenuation of 1200, 2000 and 2800 Hz will be necessary.

These filters will involve large components and some damping may be necessary, resulting in power loss. The best approach is to select a power supply which incorporates active harmonic attenuation. The harmonic attenuation will, indeed, add noise back on the incoming power lines.  This noise will need to be attenuated but the frequencies are much higher, and the filter components required are much smaller.

The cost of filtering the active harmonic attenuation is considerably lower and the efficiency does not drag down the overall power factor. Our recommendation is to avoid trying to meet CE101 without harmonic attenuation built into the power supply.

This approach allows standard design approaches for the power supply and filter with reasonable size and cost.