Motor drive for permanent magnet synchronous motor

摘要

A pulse-width modulation (PWM) inverter controller compensates for harmonics in the output current provided by a PWM inverter to permanent magnet (PM) motor. The PWM inverter controller includes a field-oriented controller (FOC) that monitors output currents provided by the PWM inverter to the PM motor and employs the monitored output currents in a current loop feedback that generates control signals. A harmonic compensator transforms monitored phase currents into rectangular waveforms having magnitudes modified based on detected harmonics within the monitored phase currents to generate compensation signals. The compensation signals generated by the harmonic compensator are summed with the control signals generated by the FOC to generate compensated control signals. A PWM signal generator generates PWM signals for controlling the PWM inverter based on the compensated control signals.

主权项

1. A pulse-width modulation (PWM) inverter controller for controlling operation of a PWM inverter connected to drive a permanent magnet (PM) motor, the PWM inverter controller comprising:
a field-oriented controller (FOC) that monitors output currents provided by the PWM inverter to the PM motor, the FOC employing the monitored output currents in a current loop feedback that generates control signals; a harmonic compensator that transforms monitored phase currents into modified rectangular waveforms having magnitudes modified based on detected harmonics within the monitored phase currents to generate compensation signals, wherein the compensation signals generated by the harmonic compensator are summed with the control signals generated by the FOC to generate compensated control signals, and wherein the harmonic compensator comprises:
a synchronous notch filter that rejects a fundamental frequency associated with the monitored output currents;a synchronous detector that isolates particular harmonics within an output of the synchronous notch filter;a proportional-integral (PI) controller that generates an output based on a magnitude of the particular harmonics isolated by the synchronous detector;a zero-cross detector that transforms the monitored phase currents into rectangular waveforms; anda plurality of multipliers that multiply the rectangular waveforms with the output of the PI controller to generate modified rectangular waveforms having a magnitude modified based on detected harmonics within the monitored phase currents to generate the compensation signals; and a PWM signal generator that generates PWM signals for controlling the PWM inverter based on the compensated control signals.