Pole Position Adaptation; Pulse Number Correction For Faults - Siemens SINAMICS S120 Function Manual

Hide thumbs Also See for SINAMICS S120:

Table of Contents

Pole position adaptation

For example, for a dirty encoder disk, the drive adds the missing pulses to the pole position

using the zero mark that is cyclically received in order to correct the pole position error. If, for

example EMC interference causes too many pulses to be added, then these will be

subtracted again every time the zero mark is crossed.

Commissioning

1. Set parameter p0430.22 = 1 to activate the "pole position adaptation" function.

Principle of operation

When the pole position adaptation is activated, the incorrect pulses on the A/B track are

corrected in the pole position for commutation. The tolerance bandwidth for the zero mark is

±30° electrical. The rate of correction is ¼ of an encoder pulse between two zero marks; this

means that sporadically missing or superfluous pulses are corrected.

When the function "Commutation with zero mark" (p0404.15 = 1) is activated, then the

system waits until fine synchronization has been completed before making a correction

(r1992.8 = 1).

Interference currents or other EMC faults can falsify encoder evaluation. However, it is

possible to correct the measured signals using the zero marks.

Commissioning

1. Set p0437.2 = 1 to activate "Pulse number correction for faults".

2. Define the permissible tolerance (encoder pulses) for the zero mark distance (p4680).

3. Define the limits of the tolerance window, up to which the drive corrects the pulse number

4. Using p4686, define the minimum zero mark length.

1. This function completely corrects encoder pulse errors up to the tolerance window

Drive functions

Function Manual, (FH1), 01/2013, 6SL3097-4AB00-0BP3

(p4681, p4682).

(p4681, p4682) between two zero marks. The rate of correction is ¼ encoder pulses per

current controller cycle. As a consequence, it is possible to continually compensate for

missing encoder pulses (for example, if the encoder disk is dirty). Using the two

parameters, set the tolerance for the deviating pulse number.

Basic functions

6.19 Tolerant encoder monitoring