Patent ID: 8278861
Filing Date: 2012-10-02
Classification: H02P

Abstract:
1. A system for detecting whether a rotation of a rotor of a motor is disturbed by a force external to the motor, wherein the rotation of the rotor occurs based on application of a voltage or a current to a coil of the motor, the system comprising: a back electromotive force (BEMF) detection module configured to detect, during each rotation of the rotor, a back electromotive force (BEMF) induced in the coil of the motor; a period determination module configured to determine a length of a period between each detection of the back electromotive force (BEMF) induced in the coil of the motor; and a control module configured to, based on the length of the period between each detection of the back electromotive force (BEMF) induced in the coil of the motor, determine whether the rotation of the rotor is disturbed by a force external to the motor.