Position sensor fault tolerant control for automotive propulsion system

A control system for a motor including a rotor, comprising:

• a sensorless sensor module that includes:
• a saliency-based estimator module that generates a first rotor position signal using a saliency-based approach;
• a back electromotive force (emf) estimator module that generates a second rotor position signal using a back emf-based approach;
• and
• a selector that selects said first rotor position signal for rotor speeds below a first rotor speed and said second rotor position signal for rotor speeds above said first rotor speed;
• a rotor position sensor that senses a position of said rotor and that generates a third rotor position signal;
• a fault detection module that senses faults in said rotor position sensor and that outputs said third rotor position signal when a fault is not detected and one of said first and second rotor position signals when said fault is detected;
• and
• an indirect field oriented control (IFOC) system that controls said motor based on a selected one of said first, second and third rotor position signals.

A method for controlling a motor including a rotor, comprising:

• generating a first rotor signal using a first sensorless approach;
• generating a second rotor signal using a second sensorless approach;
• selecting said first rotor signal for rotor speeds below a first rotor speed and said second rotor signal for rotor speeds above said first rotor speed;
• sensing at least one of a position and/or speed of said rotor using a rotor position sensor and generating a third rotor signal;
• sensing faults in said rotor position sensor;
• and
• selecting said third rotor signal when a fault is not detected and one of said first and second rotor signals when said fault is detected.

A method for controlling a motor including a rotor, comprising:

• generating a first rotor position signal using a sensorless saliency-based approach;
• generating a second rotor position signal using a sensorless back electromotive force (emf) based approach;
• selecting said first rotor position signal for rotor speeds below a first rotor speed and said second rotor position signal for rotor speeds above said first rotor speed;
• sensing a position of said rotor using a rotor position sensor and generating a third rotor position signal;
• sensing faults in said rotor position sensor;
• selecting said third rotor position signal when a fault is not detected and one of said first and second rotor position signals when said fault is detected;
• and
• using an indirect field oriented control (IFOC) approach to control said motor based on a selected one of said first, second and third rotor position signals.