Motor drive with resonance detection and impedance computation

A method to mitigate resonance in a filter of a power conversion system, the method comprising, in a first operating mode:

• turning a single one of a plurality of rectifier switching devices on for a non-zero time period;
• turning the single one of the rectifier switching devices off after the non-zero time period;
• measuring a voltage or current signal associated with the filter circuit while all of the plurality of switching devices are off after the non-zero time period,
• determining a resonant frequency based on a transient response of the measured voltage or current signal;
• and
• selectively adjusting a rectifier control parameter to mitigate filter resonance based on the resonant frequency.

A non-transitory computer readable medium with computer executable instructions for mitigating resonance in a filter of a power conversion system, the computer readable medium comprising computer executable instructions for, in a first operating mode:

• turning a single one of a plurality of rectifier switching devices on for a non-zero time period;
• turning the single one of the rectifier switching devices off after the non-zero time period;
• measuring a voltage or current signal associated with the filter circuit while all of the plurality of switching devices are off after the non-zero time period,
• determining a resonant frequency based on a transient response of the measured voltage or current signal;
• and
• selectively adjusting a rectifier control parameter to mitigate filter resonance based on the resonant frequency.