Methods and apparatus are provided for an electric vehicle embodying an
axial flux traction motor directly coupled to a wheel thereof. The
fraction motor includes a stator having coils for producing a magnetic
field, an annular rotor magnetically coupled to the stator and
mechanically to an output shaft Permanent magnets of alternating polarity
are mounted on the annular rotor. Magnetic shunts bridge a portion of the
stator slots above the coils. The magnets are arranged in groups with
group-to-group spacing exceeding magnet-to-magnet spacing. Adjacent edges
of the magnets diverge. The method comprises, looking up d- and q-axis
currents to provide the requested torque and motor speed for the
available DC voltage, combining at least one of the d- and q-axis
currents with a field weakening correction term, converting the result
from synchronous to stationary frame and operating an inverter therewith
to provide current to the coils of the motor.