User Manual V 1-4.XX User guide

13-10 Understanding the Auto-tuning Procedure
To run the inertia test:
1. Set bit 5 in Autotune Dgn Sel (parameter 173).
2. Enable the drive.
The motor should accelerate up to the speed specified in Autotune
Speed (parameter 165) at a rate limited by the torque specified in
Autotune Torque (parameter 164). The motor stops and the drive
updates Total Inertia (parameter 157). The Ki and Kp gains are
adjusted based on the results of the inertia test, the setting of Kf gain,
and the setting of Spd Desired BW (parameter 161), which is the
desired bandwidth setting for the drive’s speed regulator. Bandwidth
is limited based on the results of the inertia tests.
Tuning the Speed Regulator
Tuning the speed regulator refers to setting three regulator gains, Ki,
Kp, and Kf, to get the desired drive response to changes in speed
reference and load. The 1336 IMPACT drive uses a modified PI
(proportional integral) controller for the speed regulator. You can
adjust the setting of the regulator gains either automatically or
manually.
The Kp (proportional) and Ki (integral) gain settings for the speed
regulator affect the stability of the regulator and the response to
changes in speed reference and load disturbances. You can adjust the
Ki and Kp gains automatically by selecting a speed bandwidth. You
can also set these gains manually. The automatic method is
preferable, as it is easier and also sets the Kf Speed Loop
(parameter 160), Fdbk Filter Sel (parameter 65), and Error Filtr BW
(parameter 162) according to the Fdbk Device Type (parameter 64).
To use automatic tuning:
1. Run the inertia test to get the correct value for Total Inertia
(parameter 157). If you cannot run the inertia test, perhaps
because of mechanical limitations, you can manually enter the
inertia value. Total Inertia is defined as the time, in seconds, the
drive takes to accelerate the motor and load from zero to rated
motor speed at rated motor torque. If measurements are made at
less than rated conditions, extrapolate the results to rated
conditions.
2. Following the inertia test, the drive adjusts the maximum range
and present setting of speed bandwidth, Spd Desired BW
(parameter 161). These adjustments are made based on the
measured value of Total Inertia. High inertias imply low
bandwidths, and low inertias imply high bandwidths.
The drive sets six parameters when it completes the inertia test. How
these parameters are set depends on how Fdbk Device Type
(parameter 64) is set.
file:
Autotune
group:
Autotune Results