Suitable ac drive for multi-motor application

Zako, that was the first idea that I had. Perhaps some chokes could do the job. Using 4 inverters could do thing even worse not to mention that it would be very hard to set up, droop, etc...with high risk.

What are the cable lenghts?

Perhaps the best thing is to use 4 large chokes (4% voltage drop) and single inverter, like old school linearization.  Chokes will eliminate the cable capicitance current - if 4 cables in parallel, longer than 10m, this could be the enigma of broken IGBT. Further, they will stabilize the dynamic change of current and establish equal current flow to all motors. Chokes will last for ever - its not a money wasted.

Of course, the cable lengths and motos are equal.

https://www.automation.siemens.com/cd-static/material/info/e20001-a920-p302-v1-7600.pdf?HTTPS=REDIR

Try to google inverter parallel motor dV/dT filter, etc... There is no need to have multiple filters/reactors a single one would do the job.