Pole Position Identification - Siemens SINAMICS G115D Operating Instructions Manual

Advanced commissioning
6.17 Motor control
6.17.2.6

Pole position identification

The pole position of a synchronous motor
The pole position of a synchronous motor is the deviation between the
magnetic axis in the rotor and the magnetic axis in the stator.
The image below shows you the pole position of a synchronous motor
in a simplified cross-section.
The converter must know the pole position of the rotor in the motor in order to be able to
control the torque and speed of a synchronous motor.
Pole position identification
The converter must measure the pole position for motors not equipped with an encoder, or
for encoders, which do not supply the information regarding the pole position.
If you are using a Siemens motor, then the converter automatically selects the appropriate
technique to determine the pole position, and when required starts the pole position
identification.
Motor without an encoder
Each time the motor is switched on (ON/OFF1 command), the
converter measures the pole position.
As a result of the measurement, the motor responds to an ON
command with a delay of up to 1 second. The motor shaft
can rotate slightly during the measurement.
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Identifying the pole position
Operating Instructions, 09/2020, FW V4.7 SP13, A5E48681219B
using a measurement
SINAMICS G115D distributed drive