Tuning The Controller To The Motor - Curtis 1244 User Manual

Curtis 1244 Manual,
Rev. E

Tuning the Controller to the Motor

➁
The 1244 controller has the flexibility to be tuned to nearly any separately
excited motor from any manufacturer. Parameters in the programmer's Parame-
ters Menu allow full control of the motor's maximum armature current during
driving and braking and full control of the motor's maximum and minimum
field current as well as the field current relationship to the armature current.
This flexibility allows motor performance to be maximized while protecting it
from operating outside its safe commutation region.
In order to properly tune the controller, the following information should
be obtained from the motor manufacturer:
Maximum Armature Current Rating
£
Maximum Field Current Rating
£
Minimum Field Current Rating
£
Field Resistance, hot and cold.
£
The performance of a separately excited motor changes depending on tem-
perature. This is due to the change in field winding resistance as the motor
heats up through use. When the field winding temperature increases, so does
its resistance and therefore the maximum current that can be forced through
the winding is reduced. Reductions in the field current over the motor's typical
operating temperature range can be 10% to 50%. Since the maximum avail-
able field current determines the maximum torque that can be produced by
the motor, the vehicle's performance under load and up inclines will change as
the motor heats up. The change in performance can be limited by tuning the
motor when it is hot rather than cold. Therefore, it is recommended that the
following procedure be performed with a hot motor.
step 1. Using the programmer's Parameters Menu, set the Drive Cur-
rent Limit parameter value in each mode to the smaller of: (a)
the motor's peak armature current rating, or (b) the maximum
controller drive current limit. This value can later be adjusted
to establish the desired vehicle driving feel in each mode.
step 2. Set the Braking Current Limit parameter value in each mode to
the smaller of: (a) the maximum motor armature current rating,
or (b) the maximum controller braking current limit. This value
can later be adjusted to establish the desired vehicle braking feel
in each mode.
step 3. To set the Field Max parameter value, first decide whether you
want to maintain consistent vehicle operation throughout the
motor's temperature range. If you do, proceed to Step 4. If,
however, maintaining operational consistency across motor
temperature is not a concern, but achieving maximum torque
is, proceed to Step 5.
6 — VEHICLE PERFORMANCE ADJUSTMENT
57