Re: rotary jacobs ladder(was Magnetic quenching.)

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

Original poster: Ed Phillips <evp-at-pacbell-dot-net> 

Tesla list wrote:
 >
 > Original poster: "Virtualgod" <mike.marcum-at-zoomtown-dot-com>
 >
 > I was referring to the synchronous mechanical rectifier referred to in the
 > previous links. It seems like if there's any significant load on the output
 > the arcs will just simply be stretched out (like a climbing arc on a JL)
 > until the next electrode presentation where the process would repeat, unless
 > the motor was perfectly synchronous. I always thought that exactly 1800/3600
 > (or some multiple of 60 for 60Hz) rpm = 0 torque, so no such thing as a
 > perfectly synch motor. Maybe I'm overlooking something.

	You are.  An induction motor has to work with slip (speed less than
synchronous) to generate torque through current induced in the rotor,
but a true synchronous motor does not.   At zero torque the rotor is
locked to the line frequency at some reference phase angle and as the
torque increases it's phase lags that angle but the speed remains the
same. In other words, there is such a thing as a perfectly synchronous
motor.  Synchronous machines have other interesting properties.  For
example, there are devices called synchronous condensers (probably
synchronous capacitors these days) which can draw current at a leading
power factor, depending on the field current. They are used (or at least
have been) for power factor correction on transmission lines.

Ed