RE: LED at 60 HZ? (was RE: Radio Shack Strobes)

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

Original poster: "Steve Conner" <steve.conner-at-optosci-dot-com> 

 >does anyone on the list know if the peak
 >synchro point at 60 Hz falls at the 4 square corners of the rotor or does
it
 >fall in the center of the flat??

The rotor field lags the stator field by between almost 0 and almost 90
electrical degrees, depending on how heavily the motor is loaded. So let's
say 45. The rotor field should be aligned with the square corners of the
rotor at all times (because these are the easiest paths for flux)

The stator field rotates, but can be thought of as aligned with the stator
pole pieces whenever the stator current is at its peak. Stator current
probably lags line voltage by about 30 degrees because of the stator
inductance.

So overall, the corners of the rotor are probably about 75 degrees away from
the stator pole pieces (measured centre to centre) at line voltage peaks.
Those are electrical degrees. On a 1800rpm motor with four poles, it would
be 37.5 mechanical degrees. Which I suppose is pretty close to the centre of
the flat ::)

Steve C.