Systems and methods for control of nonisolated bidirectional power converters

A non-isolated power converter system, the system comprising:

• an N-phase power converter stage having to an alternating current (AC) side and a direct current (DC) side, with N≥1;
• an N-phase LC filter comprising one or more capacitors, wherein respective one or more neutral points of the one or more capacitors are electrically connected to a DC negative terminal of a DC source;
• and
• a control system configured to drive power switching elements of the N-phase power converter stage to convert received power and to output converted power, the control system configured to drive the power switching elements using variable frequency soft switching at a frequency of at least 20 kHz,
• where the control system is a cascaded control system comprising:
• a central controller including a processing unit, the central controller configured to:
• determine rotational reference frame targets, and
• generate N control reference targets;
• and
• at least one local controller, each of the at least one local controller including a local processing unit, each of the at least one local controller configured to:
• receive a control reference target of the N control reference targets, and
• drive a portion of the power switching elements, associated with the local controller, in accordance with the control reference target.