Re: Sync Motor Wanted

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>

Hi,

At 07:04 PM 4/17/2004, you wrote:
>Thanks very much. Yes a microwave oven fan motor won't have enough torque 
>I think. I was just experimenting :) I plan to use 50 watt motors from 
>pedestal fans, that should have enough torque.
>What sorts of induction motors does this grinding flats technique work for?

As far as I know, others correct me if not,  grinding flats in the rotors 
of just about any AC induction Tesla type motor will make it salient pole 
synchronous.  If you grind too much, currents get high due to the lowered 
inductance and overheating is a concern.  Note that torques goes down and 
currents go up with ground rotor motors.  John Freau has mentioned that 
grinding does not do be too dramatic at all to achieve our goal.  Be 
interesting to take it off layer by layer and measure all the parameters to 
find the sweet spot.

Also grinding is best done to get to 1800 RPM.  3600 RPM motors may need a 
bit more TLC to be sure the balance is not messed up too bad.

Cheers,

         Terry