Abstract: A single-stage AC/DC converter includes a boost PFC AC/DC converter and a half-bridge split-capacitor DC/DC converter. The boost PFC AC/DC converter includes a boost inductor, and the half-bridge split-capacitor DC/DC converter includes an inductor in series with a primary winding of a transformer. A method of operation of a single-stage AC/DC converter that includes a boost PFC AC/DC converter and a half-bridge split-capacitor DC/DC converter includes modulating a switching frequency of at least one switch. The method may further include maintaining a constant duty cycle, for example a duty cycle of 0.5. An implementation of the boost inductor in a boost PFC AC/DC converter of a single-stage AC/DC converter includes a variable boost inductor, such as two inductors of approximately equal inductance, and a boost inductor switching circuit, such as two single-pole, double-throw relays.

Abstract: An apparatus and method employs a rectifier, switches, and power converter that comprises a first stage, a second stage and a direct current (DC) bus between the first and second stages, to: in a first state supply rectified DC current to the first stage and a voltage adjusted current from the second stage to a load, for example a power storage device (e.g., secondary battery, ultra-capacitor(s)) at a relatively high voltage (e.g., 48 V for traction motor), and in a second state supply DC current to the first stage from the power storage device and supply a voltage adjusted current from the second stage, for example to a lower voltage DC bus or load (e.g., 12 V). The rectifier can, for example, receive grid or mains AC power.

Abstract: A single-stage AC/DC converter includes a boost PFC AC/DC converter and a half-bridge split-capacitor DC/DC converter. The boost PFC AC/DC converter includes a boost inductor, and the half-bridge split-capacitor DC/DC converter includes an inductor in series with a primary winding of a transformer. A method of operation of a single-stage AC/DC converter that includes a boost PFC AC/DC converter and a half-bridge split-capacitor DC/DC converter includes modulating a switching frequency of at least one switch. The method may further include maintaining a constant duty cycle, for example a duty cycle of 0.5. An implementation of the boost inductor in a boost PFC AC/DC converter of a single-stage AC/DC converter includes a variable boost inductor, such as two inductors of approximately equal inductance, and a boost inductor switching circuit, such as two single-pole, double-throw relays.

Abstract: An apparatus and method employs a rectifier, switches, and power converter that comprises a first stage, a second stage and a direct current (DC) bus between the first and second stages, to: in a first state supply rectified DC current to the first stage and a voltage adjusted current from the second stage to a load, for example a power storage device (e.g., secondary battery, ultra-capacitor(s)) at a relatively high voltage (e.g., 48 V for traction motor), and in a second state supply DC current to the first stage from the power storage device and supply a voltage adjusted current from the second stage, for example to a lower voltage DC bus or load (e.g., 12 V). The rectifier can, for example, receive grid or mains AC power.