Enhanced inductive sense using mutual inductance

摘要

Methods and apparatus for determining rotor position in a motor including a rotor and stator windings. The method includes measuring inductive sense values for each pair of the stator windings by performing an inductive sense routine on the motor, measuring stator winding voltage values, induced by mutual inductance between windings, for each of the stator windings by performing a mutual inductance sensing routine on the motor, and determining the rotor position based on the inductive sense values and the stator winding voltage values.

主权项

1. A method for determining rotor position in a motor including a rotor and stator windings, comprising:
driving a first pairing of the stator windings in a dummy cycle until a threshold current is exceeded; for each pairing of the stator windings,
driving the pairing of stator windings,measuring an inductive sense value for the pairing of stator windings by determining a time for a current through the pairing of stator windings to reach the current threshold, andmeasuring a stator winding voltage value, induced by mutual inductance between the pairing of stator windings, for a third stator winding by performing a mutual inductance sensing routine on the motor; anddetermining the rotor position by accessing an entry in a table based on the inductive sense values and the stator winding voltage values.