A generator system includes an AC machine including a plurality of armature coils and a rectifier circuit electrically coupled to the armature coils. The rectifier circuit includes a plurality of switches. The generator system additionally includes a sensor device electrically coupled to a control circuit. The sensor device is configured to determine a rotor position of the AC machine. The control circuit determines a desired phase angle between a phase current and an induced voltage of the AC machine and provides a control signal to the rectifier circuit to switch the switches on and off to convert an AC signal to a DC signal and to control the rotor position of the AC machine to achieve the desired phase angle.