Field oriented control of a motor with a single shunt

摘要

A method for driving a motor is provided. Pulse width modulation (PWM) signals are generated from a voltage signal and a commanded angle signal, which drives a motor with multiple phases. A motor current from a motor is measured with a single shunt and converted into a digital signal. Based on the digital signal and the commanded angle signal, direct-axis and quadrant-axis currents for the motor can be determined, and the voltage signal and the commanded angle signal can be adjusted based at least in part on the direct-axis and quadrant-axis currents.

主权项

1. An apparatus comprising:
an inverter; a motor that is coupled to the inverter; a shunt that is coupled to the inverter; a voltage generator that generates a voltage signal from a reference signal; an integrator that generates an angle signal from the reference signal; a feedback loop that is coupled to the shunt, wherein the feedback loop is configured to measure a motor current from the shunt, to determine direct-axis and quadrant-axis currents from the motor current and the commanded angle signal, and to generate a control signal; a first adder that adds the voltage signal to the control signal; a second adder that subtracts the control signal from the commanded angle signal; and a PWM controller that is coupled to the inverter and that generates a plurality of PWM signals in response to outputs from the first and second adders.