On Thu, 28 Aug 2003 16:56:10 -0400, Ned Simmons
wrote:

Every brushless motor I've worked with has had a PM
armature--no excitation required. Else why would it be
called brushless?

Separate issues. No field excitation is required because it's PM.

I thought that's what I said?

I only meant that not requiring field excitation is not why it's
called brushless. Some PM motors do have brushes.

Though I've never tried it, I'd expect one would make a
very good 3-phase generator. They certainly do a good job
of pumping up the bus voltage on the servo amp when
delivering negative torque to an overhauling load.

I agree, but it may be necessary to substitute diodes for the internal
elex.

I assume you're talking about substituting diodes for the
output stage of the amp here. Obviously if you're using the
motor as a generator, there's no need to actively commutate
the motor windings, but you do need to rectify the motor's
output if you want DC.

If the brushless motor has internal commutation electronics they may
need to be circumvented with diodes. Maybe some use external amps?