Danfoss VLT AQUA Drive FC 200 Programming Manual page 48

Parameter Description
1-30 Stator
Resistance (Rs)
(Line to common)
3 3
1-37 d-axis
Inductance (Ld)
(Line to common)
1-40 Back EMF at
1000 RPM
RMS (Line to Line
Value)
Table 3.6
NOTICE!
Motor manufacturers provide values for Stator resistance
(1-30 Stator Resistance (Rs)) and d-axis Inductance (1-37 d-
axis Inductance (Ld)) in technical specifications as between
line and common (starpoint) or between Line-Line. There is
no general standard. The different setups for Stator
Winding Resistance and Induction are shown in Figure 3.6.
Danfoss inverters always require the line to common value.
The back EMF of PM motor is defined as `Induced EMF
developed across any of two phases of stator winding of
free running Motor'. Danfoss inverters always require the
Line to Line RMS value measured at 1,000 rpm, mechanical
speed of rotation. This is shown in Figure 3.7)
Line to common (starpoint)
Figure 3.6 Motor parameters are provided in different formats.
Danfoss adjustable frequency drives always require the line to
common value.
3-22
®
VLT
This parameter gives stator winding
resistance (R ) Similar to Asynchronous
s
Motor Stator resistance. The Stator
resistance is defined for line to common
measurement. That means for line-line
data (Where stator resistance is measured
between any two lines you need to divide
it with 2).
This parameter gives direct axis
inductance of the PM motor. The d-axis
inductance is defined for phase to
common measurement. That means for
line-line data (Where stator resistance is
measured between any two lines divide it
with 2
This parameter gives back emf across
stator terminal of PM Motor at 1,000 rpm
mechanical speed specifically. It is defined
line to line and expressed in RMS Value
Line to line values
Rs and Ld
Rs and Ld
MG20O622 - VLT
AQUA Drive Programming Guide
Permanent magnet motors
Figure 3.7 Machine parameter definitions of Back EMF of
permanent magnet motors
1-39 Motor Poles
Range:
Size [2 -
related 100 ]
*
NOTICE!
This parameter cannot be adjusted while the motor is
running.
1-40 Back EMF at 1000 RPM
Range:
Size related
*
®
is a registered Danfoss trademark
Line to Line Back
Emf in RMS Value
at 1000 rpm
Speed (mech)
Function:
Enter the number of motor poles.
Poles ~n @ 50 Hz
n
2 2,700–2,880
4 1,350–1,450
6 700–960
Table 3.8
The table shows the number of poles for
normal speed ranges of various motor types.
Define motors designed for other
frequencies separately. The motor pole value
is always an even number, because it refers
to the total number of poles, not pairs of
poles. The adjustable frequency drive creates
the initial setting of 1-39 Motor Poles based
on 1-23 Motor Frequency Motor Frequency
and 1-25 Motor Nominal Speed Motor Nominal
Speed.
Function:
[ 10 - 9000 Set the nominal back EMF for the
V] motor when running at 1,000 RPM.
This parameter is only active when
1-10 Motor Construction is set to PM
motor [1] (Permanent Magnet Motor).
~n @ 60 Hz
n
3,250–3,460
1,625–1,730
840–1,153