| 摘要 |
A commutation and velocity control system of a brushless DC motor receives a velocity command signal and provides command signals to drive the brushless DC motor. The system includes a summer that receives the velocity command signal and a velocity feedback signal, a velocity loop compensator, a magnitude sensing circuit, and a polarity sensing circuit. The system also includes an integrated circuit having: (i) a velocity calculation circuit that receives first and second sampled digitized signals indicative of resolver position at a first and a second time, respectively, and determines velocity based upon the difference between said first sampled digitized signals and provides a sensed digitized velocity signal indicative thereof; (ii) a commutation logic circuit that receives said first sampled digitized signal, a velocity magnitude signal and a velocity polarity signal, and provides said command signal; and (iii) a counter that receives a signal indicative of said sensed digitized velocity signal and provides a PWM output signal indicative thereof. A filter receives said PWM output signal and generates said velocity feedback signal. |
