In article ,
Rich Grise wrote:

I just had a thought - I'm not that conversant with induction
alternators, but I've heard the term "slip" - which, driving
the shaft mechanically, faster than the synchronous speed, will
generate power - now, my quesion is, if, say, you're on a
windmill, the amount of slip will increase as the RPM increases,
right? Is there some kind of formula or graph - I'd think that
if the "slip" gets up to, like, 90 or 120 degrees, that your
generator efficiency would go back down somewhere, or am I
letting the drugs interfere with my common sense?

Speed= 0 Speed= Sync Speed= 2xSync
Slip = 1 Slip = 0 Slip = -1
| | |
| |
+Torque | |
| _ \|/ |
| / \ | |
| / \ | |
|_____/ \ | |
|____________\|_____________|
| \ ______
| |\ /
| | \ /
| | \_/
-Torque

/|\ /|\ /|\
|---Motoring--|--Generating-|

Plot a normal Torque-Speed curve from 0 to Sync Speed.

If the shaft is then driven faster than Sync then the
Torque-Speed is a mirror image of the first quadrant.

--
Tony Williams.