""If you have such a thing try a large inductance (choke) in the dc line, it works wonders with single phase, I have never seen any advantage for polyphase but lengthening the conduction period may reduce the exciting forces. Unfortunately a decent very low resistance choke will cost the earth so if you don't have one dismiss this option.""

     My electronics knowledge is just enough to enable me to ask silly questions, but here goes. I have an old blown inverter that contains a nice heavy transformer. Is it at all conceivable to use half the transformer as an inductor?