If memory serves those motors were classified as being compatable for "inverter" duty .You could probably find out on Google .VFD's are kind of neat ,single phase,rectify that and spit out variable frequency three phase .I've installed them,changed them but never did any repair on them .A box with a bunch of goobley gook with no theory of operation or wiring diagram making them kind of an OEM contraption .
At work when a unit failed I'd try to glean some info via the internet or sic a controls engineer on it .More times it just got changed out and the bones shipped off to the manufacture .
