One way to overcome this situation is by using "magnetically soft" material. Magnetically soft material has atoms that readily reverse polarity (a docile herd?) when exposed to alternating current. Naturally, since the reversing process happens more quickly, there is less wasted energy.
A ferrite sleeve around the three power conductors as they leave the drive will help to reduce common-mode noise current. Take all three conductors two or three times through the core. If it runs hot reduce the number of turns.