SINUS PENTA
PROGRAMMING GUIDE
266
/
486
34.1.4.
V/
F
P
AT T ERN
(IFD
O
NLY
)
This group of parameters which is included in the
Motor Control
Menu
defines the V/f pattern trend of the drive when it
is used as an IFD control algorithm. When setting the type of V/f pattern (e.g.
C013
for motor 1), the following curves
can be used:
•
Constant torque
•
Quadratic
•
Free setting
The diagram below illustrates three types of programmable curves compared to the theoretical V/f curve.
If
C013 = Constant Torque,
Preboost parameter
C034
allows changing the starting voltage value if compared to the
theoretical V/f curve (this allows torque compensation for losses caused by the stator impedance and a greater torque at
lower revs).
If
C013 = Quadratic,
the drive will follow a V/f pattern with a parabolic trend. You can set the starting voltage value
(
C034
), the desired voltage drop if compared to the relevant constant torque (use
C032
) and the frequency allowing
implementing this torque reduction (use
C033
).
If
C013 = Free Setting,
you can
program the starting voltage (
C034 Preboost
), the increase in voltage to 1/20 of the
rated frequency (
C035 Boost0
), and the increase in voltage (
C036 Boost1
) at programmable frequency (
C037
Frequency for Boost1
).
Figure 43: Types of programmable V/f curves
The voltage produced by the drive may be changed also by setting the
Automatic increase in torque curve
parameter
(
C038 for motor 1)
.
For the description of the parameters used in the figure above, see table below.
