Sensorless switched reluctance motor control

摘要

A method for controlling a motor and a circuit for implementing the method are provided. The method includes the steps of providing current to a first phase coil of a motor and measuring the time for the current to rise between two predetermined levels. Because current rise time is proportional to phase inductance, and therefore, rotor position, the measured current rise time can be compared to a desired current rise time to determine whether conduction intervals in the motor phases are in-phase with the position of the rotor or are lagging or leading the position of the rotor. The method finally includes the step of supplying current to one of the first phase coil and a second phase coil responsive to the measured rise time in order to bring subsequent conduction intervals into phase with the position of the rotor.