Patent ID: 7053583

Claim:
A method to control a brushless DC motor to a position, comprising: monitoring actual position of the brushless DC motor; monitoring energy used by the brushless DC motor; determining a commanded position of the brushless DC motor; determining an amount of change in commanded position per unit time; employing a zero torque commutation method to control the brushless DC motor to the commanded position only when all of the following conditions are met: the amount of chance in commanded position per unit time is less than a first threshold, a difference between the commanded position and actual position is less than a second threshold, and, the monitored energy used is less than a third threshold; and, employing a peak torque commutation method to control the brushless DC motor to achieve the commanded position when any one of the following conditions are met: the amount of change in commanded position per unit time is greater than the first threshold, the difference between the commanded position and actual position is greater than the second threshold, the monitored energy used is greater than the third threshold.