Lenze i550 - Page 139

V Voltage U
A
C
Mains voltage
f Frequency f
rated
Rated frequency
M Torque
VFCeco
The VFCeco mode has a special eect in the paral load operaonal range. Usually, three-
phase AC motors are supplied there with a higher magnesing current than required by the
operang condions. The VFCeco mode reduces the losses in the paral load operaonal
range so that savings up to 30 % are possible.
f
U
U
N
U
AC
f
N
f
max
VFCeco
V Voltage f Frequency
U
A
C
Mains voltage f
rated
Rated frequency
U
rated
Rated voltage f
max
Max. frequency
Sensorless vector control (SLVC)
In vector control, an inverted voltage model is used for calculaon. The parameters are detec-
ted via a parameter idencaon. The inverter determines the angle between current and
voltage. This imposes a current on the motor”.
Compared to the V/f characterisc control, the vector control serves to achieve improved
drive characteriscs thanks to:
•
higher t
orque throughout the enre speed range
•
higher speed accuracy and higher concentricity factor
•
higher
eciency
n
N
n
M
M
N
U/f
Vector
M Torque M
r
ated
Rated torque
n Speed n
rated
Rated speed
Applicaon areas are for instance:
•
Single driv
es with changing loads
Appendix
Good t
o know
Motor control types
139