Patent ID: 8907611
Filing Date: 2014-12-09
Classification: H02P

Abstract:
1. A method for driving a motor having a plurality of phases, the method comprising: generating first, second, and third intervals for a pulse width modulation (PWM) period from first and second voltage commands, wherein the first and second voltage commands correspond to a voltage vector for the motor, and wherein the voltage vector has an associated sector; determining a conversion formula for the first, second, third intervals based on the associated sector for the voltage vector; generating fourth, fifth, and sixth intervals from the conversion formula and the first, second, and third intervals; generating a set of PWM signals for the PWM period from the fourth, fifth, and sixth intervals; and driving the motor with the set of PWM signals, wherein the associated sector is one of a first, second, third, fourth, fifth, and six sectors, and wherein the motor has three phases, wherein the associated sector is the first sector or the fourth sector, and wherein the step of determining the conversion formula further comprises: if the voltage vector is in proximity to the sixth sector or third sector, dividing the sum of the PWM period and the second interval by two to generate the fourth interval; if the voltage vector is in proximity to the sixth sector or third sector, dividing the sum of the PWM period, the first interval, and the negative of the third interval by two to generate the fifth interval; and if the voltage vector is in proximity to the sixth sector or third sector, equating the inverse of the fourth interval to generate the sixth interval.