Compact electric range extender for an electric vehicle

摘要

An electric vehicle includes a transmission, motor, rechargeable energy storage system (RESS), auxiliary power unit (APU), and a controller. The APU has a pair of rings, at least one of which rotates with respect to the other. One ring is coaxial with and radially within the other. Ring rotation generates current in windings. A gear element is in driving connection with the rotatable ring. The APU includes an engine disposed radially within the inner ring, and a power takeoff mechanism coupled to the gear element. The controller energizes the APU to rotate a ring. A method includes positioning the APU in a vehicle body compartment, affixing an outer ring of windings to a compartment wall, and positioning a rotatable inner ring having permanent magnets radially within and coaxial with the outer ring. The engine is positioned radially within the inner ring. A power takeoff mechanism connects to the inner ring.

主权项

1. An electric vehicle comprising:
a transmission having an input member; an electric traction motor having a motor output shaft that is mechanically coupled to the input member; a rechargeable energy storage system (RESS) that is electrically connected to the electric traction motor; an auxiliary power unit (APU) having:
a set of induction windings;an outer ring;an inner ring that is coaxial with and positioned radially within the outer ring, wherein at least one of the outer and inner rings is rotatable with respect to the other to thereby generate an electrical current in the set of induction windings;a gear element in driving connection with the outer or inner ring that is rotating;an engine that is disposed radially within the inner ring, and that includes a power takeoff mechanism that is mechanically coupled to the gear element; and a controller in electrical communication with the APU and the RESS; wherein the controller is operable for determining when a level of available energy in the RESS drops below a calibrated threshold, and for selectively energizing the APU to generate electrical power via the rotation of at least one of the outer and inner rings whenever the available energy in the RESS drops below the calibrated threshold.