Patent ID: 7095194

Claim:
A method for operating an EC motor ( 2 ) which has a primary part having a coil and a secondary part having magnet segments that are magnetized in directions opposite one another, a measuring sequence being determined that has a plurality of measured value combinations that are a function of the relative position between secondary part and primary part and each include a number of measured values that correspond to the number of magnetic fields sensors (H 1 , H 2 , H 3 ) used for the determination that are mounted on the primary part and cooperate with the magnet segments, and the coil being supplied current as a function of the measured value combinations in such a manner that the secondary part moves relative to the primary part, the absolute position of the secondary part relative to the primary part being determined via positioning of the secondary part at a reference position, and an absolute value being tracked, starting from a reference position value, at each change of the measured value combination, wherein a reference sequence—which comprises a plurality of setpoint value combinations to be cycled through in succession, each of which has a number of setpoint values corresponding to the number of magnetic field sensors (H 1 , H 2 , H 3 )—is determined and stored in memory, the setpoint value combination assigned to the absolute position value is determined based on the reference sequence of the measured value combination occurring at the reference position and the number of changes in the measured value combination that have occurred since the determined reference position was reached, this setpoint value combination is compared to the measured value combination determined for the relevant absolute position value, and a fault condition is detected when a deviation occurs between the setpoint value combination and the measured value combination.