Advice from someone with the knowledge on electric motors please..

[northwest]

How did you not blow the inverter, or at least get a phase loss fault?

I have no idea and it was a cheap Chinese unit too. I did mention it on here at the time and IIRC someone else chipped in and they too had done this.

 

[m_c]

You can get single phase VFDs.

However in this application, I doubt running the motor faster will help, as it's a continuous load, so the additional inertia isn't going to help.

 

[Agroshield]

What grade of wheel is on it?

You might be able to gain a little bit by using a more open, more freely-cutting abrasive.

If you are planning to semi-automate it, what does it matter if it takes twice as long with a narrower wheel? The extra time will allow to to foul up two other things instead of just one.