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AbsPhasePosOffset Documentation Inconsistency
#1
Hello,
We are using hall-effect sensors for power-on phase referencing of a BDCM. When 'manually' determining the value of AbsPhasePosOffset using hall-sensors, the Power PMAC User Manual states:

Quote:Note the value of PhasePos when this transition occurs. If the direction sense of the Halls matches that of the commutation cycle, assign this value to Motor[x].AbsPhasePosOffset. If the direction senses do not match, assign the negative of this value plus or minus 1024 (1/2-cycle) to Motor[x].AbsPhasePosOffset.

However, the PPMAC Software Reference Manual documentation for AbsPhasePosOffset states:

Quote:If the direction senses of the sensor and the commutation cycle match (so Motor[x].AbsPhasePosOffset is positive), put this value in Motor[x].AbsPhasePosOffset. If the direction senses do not match (so Motor[x].AbsPhasePosOffset is negative), put the opposite of this value in Motor[x].AbsPhasePosOffset.

In the reverse direction sense - these do not result in the same phase offset value and it is difficult to know which is correct without knowing the exact calculation done by the Power PMAC under the hood. Any clarification would be appreciated.
Thank you, ~Andy
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#2
Note these two techniques differ in phase offset by 180 degrees in the commutation cycle.
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#3
For what it's worth the description in the PPMAC Software Reference Manual worked for me. I didn't try the technique described in the User Manual as the Software Reference Manual technique made the most sense ostensibly.
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