Three-phase inverter control for electrified vehicles

A method, comprising:

• determining, at a controller of an electrified vehicle (EV), the controller including one or more processors, three-phase AC currents at an electric motor of the EV, wherein the EV includes a three-phase inverter configured to convert a direct current (DC) from a battery system of the EV to the three-phase AC currents for the electric motor of the EV;
• determining, at the controller, a rotational position of a rotor of the electric motor;
• converting, at the controller, the three-phase AC currents to a stationary reference frame to obtain stationary currents;
• converting, at the controller, the stationary currents to a synchronous reference frame based on the rotational position of the rotor of the electric motor to obtain synchronous currents;
• determining, at the controller, synchronous voltages based on the synchronous currents and reference currents using current regulators, wherein the reference currents are based on a torque request for the electric motor, a speed of the electric motor, and a DC voltage of the battery system;
• converting, at the controller, the synchronous voltages to the stationary reference frame based on the rotational position of the rotor of the electric motor to obtain stationary voltages;
• converting, at the controller, the stationary voltages from the stationary reference frame to three-phase AC output voltages;
• selecting, at the controller, one of two zero-voltage vectors for the three-phase inverter based on the three-phase AC output voltages;
• generating, at the controller, discontinuous pulse-width modulation (DPWM) duty cycles based on the three-phase AC output voltages, the three-phase AC currents, and the zero-voltage vector;
• and
• controlling, by the controller, switching of the three-phase inverter using the DPWM duty cycles.