Rockwell Automation 7000 PowerFlex Medium Voltage AC Drive (B Frame) Commissioning - ForGe Control User Manual
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Rockwell Automation Publication 7000-IN012B-EN-P - June 2014
Chapter 4 Commissioning the Drive
Flux Regulator
Set Flux Regulator Bandwidth to the default value for almost all applications. Lm
Rated, Lmd, T Rotor and Total Inertia are usually unknown and must be
measured. Although these motor parameters change with different operating
conditions, the variations do not significantly affect the operation of the flux
regulator.
The other aspect of flux control is the variation of motor flux with speed. This is
determined by two parameters:
• Base Speed in Flux Control
• FlxCmd RatedLoad in Flux Control
In most applications, the motor runs at constant flux below rated speed and
constant voltage above rated speed. The motor flux is normally set to a level that
provides rated voltage at rated speed and full load. The flux level required to
achieve this is a function of the motor parameters. The flux regulator auto-tuning
determines a value of rotor flux that should provide rated motor voltage at full
load and rated speed and sets the flux command parameter to this value.
Speed Regulator
For more details, refer to
Speed Regulator Manual Tuning (Induction Motor) on
.
If a position encoder is fitted to the motor, the FluxSpeed regulator auto-tuning is
performed with the encoder feedback turned off because it is assumed that the
encoder has not been aligned with the rotor axis yet. Since less starting torque is
produced with the encoder feedback off, this test should be performed with
reduced load. The encoder offset measurement is also most accurate with no load
on the motor.
Flux Speed Regulator Auto-tuning (Synchronous Motor)
Tune the Flux Speed Regulator, with the motor running at constant speed, using
the following procedure:
1.
Ensure that the analog reference for the field current has been set up as
described previously, and that parameter L Total Leakage has been set to
the correct value.
2.
Set parameter Autotune Select in Autotuning to FluxSpeed Reg.