This looks like a variable reluctance stepper motor with 20 steps per rev. The added permanent magnets will cause the variable reluctance stepper motor to behave more like a permanent magnet stepper motor.
Variable reluctance motors have exceptionally low efficiencies. Hence, a boost in magenetic efficiency may make this motor more efficient than its variable reluctance cousins.
Permanent magnet stepper motors place the permanent magnet on the rotor, or between layers on the stator. This motor places the permanent magents on the stator, but in a rather inconvenient place. As such, it is not obvious how this motor is better than other permanent magnet stepper motors.
Conventional induction and brushless DC motors are much more efficient than stepper motors. As such, stepper motors tend to be used only in specialized or low power applications. This motor is probably a special purpose design, only well suited for certain specialized applications.
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Variable reluctance motors have exceptionally low efficiencies. Hence, a boost in magenetic efficiency may make this motor more efficient than its variable reluctance cousins.
Permanent magnet stepper motors place the permanent magnet on the rotor, or between layers on the stator. This motor places the permanent magents on the stator, but in a rather inconvenient place. As such, it is not obvious how this motor is better than other permanent magnet stepper motors.
Conventional induction and brushless DC motors are much more efficient than stepper motors. As such, stepper motors tend to be used only in specialized or low power applications. This motor is probably a special purpose design, only well suited for certain specialized applications.