Abstract:
A method and apparatus for determining a motor fault in an electric motor (50) determines a calculated rotor position (nullcalc) of the electric motor. The calculated rotor position (nullcalc) is compared to a measured rotor position (nullmeas) of the electric motor (50) to determine a rotor position error (nullerr). A motor fault in the electric motor (50) is determined when the rotor position error (nullerr) exceeds a predetermined maximum rotor position error (nullerrnullmax).