Permanent magnet motors
e30bc009.11
Line-to-line back
EMF in RMS value
at 1000 RPM
speed (mech)
Illustration 3.7 Machine Parameter Denitions of Back EMF of
PM Motors
1-38 q-axis Inductance (Lq)
Range: Function:
Size related* [0.000 - 1000
mH]
NOTICE
This parameter cannot be
adjusted while the motor is
running.
Set the value of the q-axis
inductance. See the motor
datasheet.
1-39 Motor Poles
Range: Function:
Size
related*
[2 -
132 ]
NOTICE
This parameter cannot be adjusted
while the motor is running.
Enter the number of motor poles.
Poles ~n
n
@ 50 Hz ~n
n
@ 60 Hz
2 2700–2880 3250–3460
4 1350–1450 1625–1730
6 700–960 840–1153
Table 3.7 Pole Counts and Related
Frequencies
Table 3.7 shows the pole numbers for normal
speed ranges of various motor types. Dene
motors designed for other frequencies
separately. The motor pole value is always an
even number, because it refers to the total
pole numbers, not pairs of poles. The
frequency converter creates the initial setting
of parameter 1-39 Motor Poles based on
parameter 1-23 Motor Frequency and
parameter 1-25 Motor Nominal Speed.
1-40 Back EMF at 1000 RPM
Range: Function:
Size
related*
[ 10 -
9000 V]
Set the nominal back EMF for the motor
when running at 1000 RPM. This
parameter is only active when
1-40 Back EMF at 1000 RPM
Range: Function:
parameter 1-10 Motor Construction is set
to [1] PM, non-salient SPM.
1-44 d-axis Inductance Sat. (LdSat)
Range: Function:
Size
related*
[0 -
1000 mH]
Enter the inductance saturation of L
d
.
Ideally, this parameter has the same
value as parameter 1-37 d-axis Inductance
(Ld). If the motor supplier provides an
induction curve, enter the induction
value at 200% of the nominal value.
1-45 q-axis Inductance Sat. (LqSat)
Range: Function:
Size
related*
[0 -
1000 mH]
This parameter corresponds to the
inductance saturation of L
q
. Ideally, this
parameter has the same value as
parameter 1-38 q-axis Inductance (Lq). If
the motor supplier provides an induction
curve, enter the induction value at 200%
of the nominal value.
1-47 Torque Calibration
Option: Function:
Use this parameter to optimize the torque estimate
in the full speed range. The estimated torque is
based on the shaft power, P
shaft
= P
m
- R
s
x I
2
. Make
sure that the R
s
value is correct. The R
s
value in this
formula is equal to the power loss in the motor, the
cable, and the frequency converter. When this
parameter is active, the frequency converter
calculates the R
s
value during power-up, ensuring
the optimal torque estimate and optimal
performance. Use this feature in cases when it is
not possible to adjust parameter 1-30 Stator
Resistance (Rs) on each frequency converter to
compensate for the cable length, frequency
converter losses, and the temperature deviation on
the motor.
[0]
*
O
[1] 1st
start
after
pwr-
up
Calibrates at the rst start-up after power-up and
keeps this value until reset by a power cycle.
[2] Every
start
Calibrates at every start-up, compensating for a
possible change in motor temperature since last
start-up. The value is reset after a power cycle.
[3] 1st
start
with
store
The frequency converter calibrates the torque at the
rst start-up after power-up. This option is used to
update motor parameters:
Parameter Description
VLT
®
AQUA Drive FC 202
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