Efficient Networks Siemens Sinamics S120 - Manual (Page 99)

Servo control
3.13 Pole position identification
Drive Functions
Function Manual, (FH1), 07/2007 Edition, 6SL3097-2AB00-0BP4
99
● Hall sensor
● Resolver with a multiple integer ratio between the motor pole pair number and the
encoder pole pair number
● Incremental encoder with a multiple integer ratio between the motor pole pair number and
the encoder pulse number
The pole position identification is used for:
● Determining the pole position (p1982 = 1)
● Determining the angular commutation offset during commissioning (p1990 = 1)
● Plausibility check for encoders with absolute information (p1982 = 2)
WARNING
When the motors are not braked, the motor rotates or moves as a result of the current
impressed during the measurement. The magnitude of the motion depends on the
magnitude of the current and the moment of inertia of the motor and load.
Notes regarding pole position identification
The relevant technique can be selected using parameter P1980. The following techniques
are available for a pole position identification routine:
● Saturation-based 1st+ 2nd harmonics (p1980 = 0)
● Saturation-based 1st harmonics (p1980 = 1)
● Saturation-based, two-stage (p1980 = 4)
● Saturation-based (p1980 = 10)
The following limitations/constraints apply for the saturation-based motion technique:
● This technique can be used for both braked and non-braked motors.
● It can only be used for a speed setpoint = 0 or from standstill.
● The specified current magnitudes (p0325, p0329) must be sufficient to provide a
significant measuring result.
● For motors without iron, the pole position cannot be identified using the saturation-based
technique.
● For 1FN3 motors, no traversing with the 2nd harmonic should take place (p1980 = 0,4).
● With 1FK7 motors, two-stage procedures must not be used (p1980 = 4). The value in
p0329, which is set automatically, must not be reduced.
For the motion-based technique, the following constraints apply:
● The motor must be free to move and it may not be subject to external forces (no
hanging/suspended axes)
● It can only be used for a speed setpoint = 0 or from standstill.
● If there is a motor brake, then this must be open (p1215 = 2).
● The specified current magnitude (p1993) must move the motor by a sufficient amount.