In article , jim beam wrote:
On 03/25/2013 05:57 PM, Jamie wrote:
jim beam wrote:

Another way to do this, is to have an inductor on board with the
speed control circuit. You would PWM that inductor in series to a filter
cap
on the output which will then give you a clean variable DC. THe inductor
will be doing all variable voltages.

ok, as i understand it, and as i said to scott earlier, this is a
problem because it mungs low speed motor start and low speed torque.

Not really, it's feeding the motor with variable DC from that integrator
stage. It's not much different than a big rheostat in terms of starting
torque. It's just more expensive and less reliable and quieter.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."