THe last two days I have broke my inverters, 2.2 kw (with 2.2kw watercooled spindle) and 1.5 kw (with 1.5kw aircooled spindle). Both times the endmill smasched into the material. The spindle stops rotate and I swithed of the machine at once. No smoke anywhere. I powered up again and it looks fine. No errors on the display. Started the inverter and the motor sounds like spinning but it doesn't. When turning the rotor with my fingers it start to rotate but very weak torque. I meassured the phases out and found that one of them have no or very little voltage and amperes compared to the two others.
My first question is is there an internal protection against powerpeaks? I assume it was a powerpeak when the rotor retards from 16000 rpm to just zero rpm. I have meassure the motor phases and it seems to be okay.
Does someone have had a similar issue? I intend to see if I can repair the inverters by myself but would like to have some advice where to start. Maybe it is enough to replace the IGBTs at the faulty phase?
Any suggestions will be appreciated.

Now I have ordered a 3kw Huanyang inverter and are looking for some advice to setup the parameters to work with the 2.2 kw spindle. Maybe this will be the last inverter I have to buy.

Thanks in advance.