EV Battery Charger DC/DC Bidirectional Converter with Hybrid Resonant Frequency and Phase Shift Modulation Charge Mode Control and Dual Active Bridge Discharge Mode Control

A bidirectional series-resonant power converter comprising:

• a transformer;
• an asymmetrical resonant tank electrically coupled to the transformer;
• a primary side inverter electrically coupled to a primary side of the transformer;
• the resonant tank including at least a resonant capacitor (Cr) exclusively at the primary side, and
• a secondary side rectifier electrically coupled to a secondary side of the transformer,
• wherein the resonant tank further comprises at the secondary side of the transformer, a coupling inductance to facilitate energy storage enabling soft switching and bidirectional power flow and a sensor configured to measure both AC and DC components, thereby eliminating the need for DC blocking capacitors on the secondary side.

A method of operating a bidirectional series-resonant power converter, the converter comprising a transformer;

• an asymmetrical resonant tank electrically coupled to the transformer;
• a full-bridge primary side inverter electrically coupled to a primary side of the transformer;
• the resonant tank including at least a resonant capacitor (Cr) exclusively at the primary side, and a secondary side rectifier electrically coupled to a secondary side of the transformer, wherein the resonant tank further comprises at the secondary side of the transformer, a coupling inductance to facilitate energy storage enabling soft switching and bidirectional power flow, the method comprising:
• operating the full-bridge primary side inverter and the full bridge secondary side rectifier at a nominal 50% duty cycle with a transistor dead-time td introduced between complementary gate signals to facilitate zero voltage switching (ZVS).