
Parameters 285
97
Switching frequency; slip gain; voltage reserve; flux
braking; anti-cogging (signal injection); IR compensation.
Defines the switching frequency of the drive that is used
as long as the drive does not heat too much. See section
on page
.
Higher switching frequency results in lower acoustic
noise.
In multimotor systems, do not change the switching
frequency from the default value.
4 kHz
4 kHz.
4
8 kHz
8 kHz.
8
12 kHz
12 kHz.
12
Lowest switching frequency that is allowed. Depends on
the frame size.
1.5 kHz
1.5 kHz. In some larger frame sizes 1 kHz is used instead. 1.5
2 kHz
2 kHz.
2
4 kHz
4 kHz.
4
8 kHz
8 kHz.
8
12 kHz
12 kHz.
12
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%
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%
No.
Name/Value
Description
Default
FbEq 16
ACS180 FW.book Page 285 Tuesday, March 9, 2021 2:25 PM