Siemens Sinamics S120 Function Manual page 150

Vector control
4.1 Sensorless vector control (SLVC)
Figure 4-5 Zero point in closed-loop operation down to zero speed
Note
Only open-loop controlled operation is permitted when using a sine-wave filter.
Note
1FW4 torque motors
Siemens 1FW4 torque motors can be started from standstill and operated in the closed-loop
torque controlled mode. The function is activated with parameter p1750.5 = 1.
Third-party motors must be checked on a case-for-case basis.
Basic conditions for the use of third-party motors
● Experience shows that this method is extremely well suited for interior permanent magnet
● The ratio of stator quadrature reactance (Lsq): Stator direct-axis reactance (Lsd) must be
● The asymmetrical reactance ratio (Lsq:Lsd) is maintained in the motor up to a certain
The following parameter input is prerequisite for optimal performance:
● Input of the saturation characteristic: p0362 to p0369
● Input of the load characteristic: p0398, p0399
Commissioning sequence for closed-loop controlled operation down to zero speed:
148
synchronous motors (IPMSM).
> 1 (recommendation: minimum > 1.5).
current; this determines the possible operating limits of the method. If it you want to be
able to operate the method up to the rated motor torque, the reactance ratio must be
maintained up to the rated motor current.
Function Manual, (FH1), 01/2012, 6SL3097-4AB00-0BP2
Drive functions