Motor Drive Query

Usually I approach control systems design as custom solution -- to date
my customers have all had requirements that pointed to custom boards, or
at least to custom software.

I'm working with a customer who has a square box with plenty of room, so
it makes sense to use off the shelf components and rope them together
with appropriate cables and glue software, and this is what I'm doing.

My problem is that the motor drive (Teknic) that the customer chose has
a very high maximum current value, and we're running into weight
constraints in the power supply.  Because of the drive's occasional
current demands, any switching supply would need to be seriously
oversized, expensive, and none too light.  The customer currently has a
linear supply in there which is better at absorbing the occasional
current transient, but it weighs a ton.

I could alleviate many of the power supply constraints if I could get a
motor drive that could be configured to drive at a specified current and
no higher.  Even better would be a drive that can be configured to
_consume_ no more than a specified current.

Are there any such critters out there that you know of?  The motor is a
low-voltage unit; it requires 12-24V or so to operate, so the drive
needs to correspond.  The drive we're currently using works with a
brushless motor with an encoder, and takes a pulse and direction command
from the controller -- I'd prefer something similar, but I'd be willing
to use a different interface if it meant finding a drive with my desired
current control properties.

Thanks in advance.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

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