Rockwell Automation 7000 PowerFlex Medium Voltage (B Frame) Commissioning - ForGe (PanelView 550) - Manual (Page 105)

Rockwell Automation Publication 7000-IN006B-EN-P - May 2013 101
Commissioning the Drive Chapter 5
• Regulator Limit - indicates that the torque command was greater than Trq
Limit Motoring or Trq Limit Braking. The measured inertia value is
invalid. Set the Autotune Trq Stp or Autotune Spd Cmd parameter to a
lower value and repeat the test.
• Tuning abort - indicates that the deviation in motor speed was greater than
10 Hz. The measured inertia value is invalid. Set Autotune Trq Stp to a
lower value and repeat the test.
• Inertia high - indicates that the measured total inertia is greater than 20
seconds. This warning indicates an unusually high inertia value. For a very
high inertia load such as a large fan, this may be a valid result; set Total
Inertia manually to equal Autotune Inertia. However, a high inertia
measurement might also indicates that the Autotune Trq Stp value 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
tune the speed regulator’s step response manually using the following procedure.
To obtain accurate results, the load torque must be steady.
Slip Rated
LmRated
T
rotor
=
RPM Sync
RPM Rated RPM Sync
Freqmotor Slip Rated
) (
) 2 (
−
× = π