ABB ACS880 ESP, Firmware Manual

Page: 348 / 494

348 Parameters
96
97 Motor control
Motor model settings.
97.03 Slip gain Defines the slip gain which is used to improve the
estimated motor slip. 100% means full slip gain; 0%
means no slip gain. The default value is 100%. Other
values can be used if a static speed error is detected
despite having the setting at full slip gain.
Example (with nominal load and nominal slip of 40 rpm): A
1000 rpm constant speed reference is given to the drive.
Despite having full slip gain (= 100%), a manual
tachometer measurement from the motor axis gives a
speed value of 998 rpm. The static speed error is 1000
rpm - 998 rpm = 2 rpm. To compensate the error, the slip
gain should be increased to 105% (2 rpm / 40 rpm = 5%). 100%
0…200% Slip gain. 1 = 1%
97.04 Voltage reserve Defines the minimum allowed voltage reserve. When the
voltage reserve has decreased to the set value, the drive
enters the field weakening area.
Note: This is an expert level parameter and should not be
adjusted without appropriate skill.
If the intermediate circuit DC voltage
U
dc
= 550 V and the
voltage reserve is 5%, the RMS value of the maximum
output voltage in steady-state operation is
0.95 × 550 V / sqrt(2) = 369 V
The dynamic performance of the motor control in the field
weakening area can be improved by increasing the voltage
reserve value, but the drive enters the field weakening
area earlier.
-2%
-4…50% Voltage reserve. 1 = 1%
97.05 Flux braking Defines the level of flux braking power. (Other stopping
and braking modes can be configured in parameter group
21 Start/stop mode ).
See section Flux braking (page 75 ).
Note: This is an expert level parameter and should not be
adjusted without appropriate skill.
Disabled
Disabled Flux braking is disabled. 0
Moderate Flux level is limited during the braking. Deceleration time is
longer compared to full braking. 1
Full Maximum braking power. Almost all available current is
used to convert the mechanical braking energy to thermal
energy in the motor. 2
97.06 Flux reference select Defines the source of flux reference.
Note: This is an expert level parameter and should not be
adjusted without appropriate skill. User flux
reference
Zero None. 0
User flux reference Parameter 97.07 User flux reference . 1
Other Source selection (see Terms and abbreviations on page
101 ).
-
97.07 User flux reference Defines the flux reference when parameter 97.06 Flux
reference select is set to User flux reference .
100.00%
0.00…200.00% User-defined flux reference. 100 = 1%
No. Name/Value Description Def/
FbEq16