A brushless DC motor modifies motor commutation events to reduce noise by providing overlapping activation of the switch being deactivated with the switch being newly activated so that three switches are temporarily activated. The newly activated switch is pulse width modulated with a motor torque controlling...http://www.google.com/patents/US6002226?utm_source=gb-gplus-sharePatent US6002226 - Brushless DC motor control method and apparatus for reduced commutation noise
