Lenze EVF9383 User Manual
Page 175
Operating mode
Vector control
6.8
6.8.2
l
6.8−11
EDSVF9383V EN 7.1−04/2012
In general the vector control can be operated without any further measures.
The vector control must only be optimised in case of the following drive
behaviour:
Drive behaviour
Remedy
Operation without feedback:
l
The current consumption in idle
state differs widely from the
rated magnetising current (I
mR
»
I
N
× sin
j) . Calculate sin j from
the cos
j of the motor
nameplate.
l
The drive has an uneven starting
performance
1. Optimise setpoint for the motor magnetising
current. (
^ 6.11−9)
2. Stator inductance (C0092) must be adapted after
motor parameter identification.
The calculation of the stator inductance by the
motor data identification is based on the motor data
entered before and does not consider the physical
leakage of the motor and the inductive reactance of
the motor cable.
0,37
22
90
C0092
C0092
-15 %
+15 %
0
400 P [kW]
N
9300vec040
Tendency of the correction of C0092
PN: rated motor power
Lack of speed stability at high load
(setpoint and motor speed are not
proportional anymore)
Use C0021 (slip compensation) to change the influence
of the rotor resistance (C0082) proportionally:
l
Reduce the value in C0021 at an increasing speed
(negative values)
l
Increase the value in C0021 at a decreasing speed
Note: If you activate the vector control (C0006 = 1),
C0021 is automatically set to 0 %.
Unstable control at higher speeds
l
Reduce the gain of the speed controller (C0070) (if
required, speed−dependent adaptation via function
block CURVE1 and MCTRL−VP−ADAPT)
l
Control value in C0092 by comparing the current
consumption in no−load operation with the rated
magnetising current (I
mR
» I
N
× sin
j).
l
Optimise oscillation damping (C0234 ... C0236)
Unstable control at higher speeds
and high torque at high power
(> 55 kW)
l
Reduce gain of the I
max
controller (C0075) or reduce
gain and influence of the oscillation damping (at a
power of 55 ... 90 kW).
l
For operation with feedback, deactivate oscillation
damping with C0234 = 0.
Unstable control in field weakening
range for operation with speed
feedback
l
Reduce integral−action time of the field controller via
C0077
l
Increase gain of the I
max
controller (C0075)
Error messages OC1 or OC3 with
short acceleration times (C0012)
compared with the load (controller
cannot follow the dynamic
processes).
l
Increase gain of the I
max
controller (C0075)
l
Reduce integral−action time of the I
max
controller
(C0076)
l
Increase acceleration time (C0012)
Mechanical resonances at certain
speeds
The function block NLIM1 serves to suppress those
speed ranges in which resonances occur (see chapter
"Function library").
Speed oscillations in no−load
operation at speeds >
1
/
3
rated
speed
The oscillation damping minimises speed oscillations
(see "Optimising operational performance" in chapter
"Commissioning")
Optimising vector control