User`s guide

97
CHAPTER 6 - DETAILED PARAMETER DESCRIPTION
Range
[Factory Setting]
Parameter
Unit
Description / Notes
CompensationZone
Maximum
(P142)
Output Voltage
Output
Frequency
Field
Weakening (P145)
4 Hz
0
Figure 6.8
- V/F curve with automatic torque boost
(automatic IxR compensation)
P138
(2)
0.0 to 10.0
Slip
[0.0]
Compensation
0.1 %
The parameter P138 is used in the motor slip
compensationfunction.
This function compensates the drop of the motor speed
due to load, which is a inherent characteristic relating to
the operation principle of the induction motor.
This speed drop is compensatedbyincreasing theoutput
frequency (and voltage) (applied to the motor) as a
function of the increase of the active motor current, as
shown in the block diagram and in the V/F curve below.
P137
(2)
0.00 to 1.00
AutomaticTorque
[
0.00
]
Boost
-
(AutomaticIxR
Compensation)
Theautomatic torque boostcompensates for the voltage
drop in thestator resistance in functionof the activemotor
current.
The criteria for setting P137 are the same of the
parameter P136.
Figure 6.7
- Block diagram of the automatic torque boost function
Slip
Compensation
OutputActive
Current (I
a
)
Frequency
Reference (F*)
Ramp Input
Frequency (Fe)
F
Filter
P138
Figure 6.9
- Block diagram of the slip compensation function
Speed
Reference (F*)
Output
Active
Current (I
a
)
Filter
Automatic
Torque Boost
P137
Manual
Torque Boost
P136
P007
Motor
Voltage