Integrated power conversion systems and methods for use in an electric vehicle having an electric motor, a primary high-voltage energy source, and an auxiliary energy source including a traction inverter module operable for converting a DC current generated by the high-voltage energy source into an AC current capable of powering the electric motor, and a DC/DC converter operable to step-down a voltage of the high-voltage energy source or step-up a voltage of the auxiliary energy source, wherein the traction inverter module and the DC/DC converter may share one or more common components, such as a common high-voltage DC bus capacitor, a common DC bus bar, and/or a common high-voltage transistor.