Rockwell Automation 7000L PowerFlex Medium Voltage AC Drive (C-Frame) - ForGe Control User Manual
Page 247
Rockwell Automation Publication 7000L-UM301D-EN-P - June 2014
247
Commissioning
Chapter 4
Regulator Limit
- indicates that the torque command was greater than
Trq Limit
Motoring or Trq Limit Braking. The measured inertia value is invalid. Parameter
Autotune Trq Stp or parameter Autotune Spd Cmd must be set to a lower value
and the test repeated.
Tuning abort
- indicates that the deviation in motor speed was greater than
10 Hz. The measured inertia value is invalid. Parameter
Autotune Trq Stp must be
set to a lower value and the test repeated.
Inertia high
- indicates that the measured total inertia is greater than 20 seconds.
This warning is intended to draw attention to an unusually high inertia value. For
a very high inertia load such as a large fan, this may be a valid result and parameter
Total Inertia should be manually set equal to Autotune Inertia. However, a high
inertia measurement could also be produced by a value of
Autotune Trq Stp which
is too low.
Flux Regulator Manual Tuning [Induction Motor]
1.
Adjust the reference command to a value between 20 and 30 Hz.
2.
Start the drive and wait for it to accelerate to the commanded speed.
3.
Record the value of parameter
Lm Measured (134) in Motor Model.
4.
Stop the drive.
5.
Set parameter
Lm Rated in Motor Model to the recorded value of
Lm Measured.
6.
Calculate an approximate value of the rotor time constant using the
following formula:
Where
Set the parameter
T Rotor in Motor Model to the calculated value.
Speed Regulator Manual Tuning [Induction Motor]
If it is not possible to tune the speed regulator using the auto-tune function, then
the step response of the speed regulator can be tuned manually using the
following procedure. To obtain accurate results, the load torque must be steady.
1.
Set parameter
SpdReg Bandwidth in Speed Control to 1.0 rad/sec.
T
rotor
LmRated
RatedSlip
--------------------------
=
Rated Slip
2
Freqmotor
Sync RPM
Rated RPM
–
Sync RPM
---------------------------------------------------------------
=