Not quite right.
Many motors, brushless servos being one, can run at any speed indefinitely.
(Stepper motors. )
Example:
I use a 2.5 kW ac servo on my lathe, and it can run at any speed, for
10.000 hours expected lifetime.
It increments, or indexes, at 1/30.000 counts per turn, so can position
to 360 degrees/30.000 == 0.01 degrees accuracy to any position.
Of course, the full power, in this case 2.5 kW, is only available once
you run fast enough.
At lower speeds it has 30 Nm x 3 = 90 Nm (peak) torque. Grin.
A motor like this would actually run a boat really well, probably upto
about a 10 m sailboat, at 4-5 knots.
For example mostly old-technology, relatively inefficient dc motors tend
to overheat.
On 27/02/2016 18:57, dominic.amann@gmail.com [electricboats] wrote:
> Although electric motors produce decent torque at low RPM, they will
> run hot doing so. Your motor is rated at a certain continuous current
> based on its "ideal" RPM - in other words, its ideal effective
> voltage. Running the motor outside its sweet spot in terms of RPM for
> long periods will result in greater heat generation, and lowered
> efficiency.
--
-hanermo (cnc designs)
Posted by: Hannu Venermo <gcode.fi@gmail.com>
| Reply via web post | • | Reply to sender | • | Reply to group | • | Start a New Topic | • | Messages in this topic (7) |
No comments:
Post a Comment