Parameter and variable descriptions 6-17 – Rockwell Automation 1557 MEDIUM VOLTAGE AC DRIVE User Manual
Page 73
PARAMETER AND VARIABLE DESCRIPTIONS
6-17
1557-UM050F-EN-P – June 2013
Commutation Inductance [L commutation]
Linear number:
117
Minimum value:
0.00 pu
Maximum value:
0.50 pu
Default value:
0.10 pu
This parameter specifies the commutating inductance of the line converter. This is roughly equal to the
impedance of the supply, including the isolating transformer if present, expressed in the per unit system of the
drive. The commutating inductance is used in the hardware reconstruction of the line voltage to compensate for
commutation notches. It is also used in the calculation of the retard limit for the line converter. This parameter
can be set manually or by autotuning.
DC Current Test Command [Idc command test]
Linear number:
119
Minimum value:
0.000 pu
Maximum value:
1.000 pu
Default value:
0.000 pu
This parameter specifies the value of the dc current command when the drive is operating in dc current test
mode. It is not saved and is initialized to zero at power up.
DC Current Reference Step [Idc ref step]
Linear number:
120
Minimum value:
0.000 pu
Maximum value:
1.000 pu
Default value:
0.000 pu
This parameter specifies the magnitude of the step that is added to the dc current command to demonstrate the
step response of the current loop. It is not saved and is initialized to zero at power-up.
9 Motor Model Parameters
Stator Resistance [R stator]
Linear number:
129
Minimum value:
0.00 pu
Maximum value:
0.20 pu
Default value:
0.00 pu
This parameter specifies the per unit stator resistance of the motor. It is used in the calculation of the stator
voltage and in the hardware reconstruction of the rotor flux. Stator resistance is usually less than 0.01 pu
unless the motor is very small or the motor cables are very long. This parameter can be set manually or by
autotuning.
Warning: An excessively high stator resistance may cause the drive to become unstable at low speed high
load.
Total Leakage Inductance [L total leakage]
Linear number:
130
Minimum value:
0.00 pu
Maximum value:
0.74 pu
Default value:
0.20 pu
This parameter specifies the per unit total leakage, short circuit, or transient inductance (Ls') of the motor. It is
approximately equal to the sum of the stator and rotor leakage inductance’s, and the cable inductance, and has
a typical value of 0.20 pu. The leakage inductance parameter is used in the calculation of the stator voltage
and in the hardware reconstruction of the rotor flux. This parameter can be set manually or by autotuning.
Warning: An excessively high leakage inductance may cause the drive to become unstable at high speed high
load.