| 摘要 |
<p>Methods and apparatus for controlling a polyphase brushless DC motor in implantable medical device applications are provided. The back emf of a selected phase (440) of the motor is sampled while a drive voltage of the selected phase is substantially zero (400, 430). Various embodiments utilize sinusoidal (400) or trapezoidal (430) drive voltages. The sampled back emf (440) provides an error signal indicative of the positional error of the rotor. The error signal is provided as feedback to control (650) a frequency of the drive voltage. A speed control (660) generates a speed control signal corresponding to a difference between a commanded angular velocity and an angular velocity inferred from the frequency of the drive voltage. The speed control signal is provided as feedback to control an amplitude of the drive voltage.</p> |
