Fluxspeed regulator [induction motors – Rockwell Automation 7000L PowerFlex Medium Voltage AC Drive (C-Frame) - ForGe Control User Manual
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Rockwell Automation Publication 7000L-UM301D-EN-P - June 2014
Chapter 4
Commissioning
L Leakage Low
- indicates that the measured leakage inductance is less than 0.10
pu. Possible causes are:
1.
The motor is much larger than the drive and the motor nameplate
parameters do not correspond to the actual motor ratings.
2.
Because of the design of the motor, this method of measuring leakage
inductance does not produce a valid result. The leakage inductance will
have to be obtained from the motor data sheet, or if this is not possible,
parameter
L Total Leakage should be set to its default value of 0.20 pu.
L Leakage High
- indicates that the measured leakage inductance is greater than
0.35 pu. Possible causes are:
1.
The inductance of long motor cables is increasing the apparent leakage
inductance of the motor. In this case, the measured leakage inductance is
probably correct.
2.
The motor is very small (leakage inductance generally increases with
decreasing motor size).
3.
Because of the design of the motor, this method of measuring leakage
inductance does not produce a valid result. The leakage inductance will
have to be obtained from the motor data sheet. If this is not possible,
parameter
L Total Leakage should be set to its default value of 0.20 pu.
3. FluxSpeed Regulator [INDUCTION MOTORS]
This method combines the auto-tuning of the Flux and Speed regulator in a
single step. It calculates parameters,
Lm Rated (P131), T Rotor (P132) in Motor
Model Group and Total Inertia (82) in Speed Control group.
Flux Regulator
The tuning of the flux regulator for an induction motor is determined by three
parameters:
1.
FlxReg Bandwidth in Flux Control
2.
Lm Rated in Motor Model
TIP
For synchronous motors, please refer FluxSpeed Regulator for Synchronous
motor.
TIP
During this auto-tune step the motor will run at speed set in
Autotune Spd Cmd. The default setting is 30Hz. Make sure the motor rotates
during this auto-tune. Motor rotation must be verified either physically or
monitoring FlxFbk VoltModel (342). It is possible that stall condition may
calculate wrong tuning parameters. If it happens, make sure the tuning
parameters Lm Rated, T Rotor, Total Inertia are set to default before starting this
tuning again.