Patent ID: 7258183
Filing Date: 2007-08-21
Classification: B60K,B60L,B60W,Y02T,Y10S

Abstract:
1. A method for operating a vehicle having a first electrical bus for providing power to accessory loads and a second electrical bus electrically coupled to the first electrical bus, the second electrical bus including an ultracapacitor and at least one electric motor/generator for providing electric motor traction assist to wheels of the vehicle, the method comprising: providing electric motor assist by powering the electric motor/generator with energy from the ultracapacitor; regulating a voltage of the first electrical bus within a predefined voltage range while the electric motor provides the electric motor traction assist; wherein regulating the first electrical bus within the predefined voltage range includes controlling a DC/DC converter electrically coupled between the first and second electrical buses to prevent electric energy to flow from the second to the first bus during the electric motor traction assist; and providing energy from the first to the second electrical bus if an ultracapacitor voltage of the ultracapacitor is below a predefined voltage limit by controlling the DC/DC converter such that electric energy flows from the first to the second electric bus while still regulating the first electric bus within the predefined voltage range, the electric motor traction assist provided based on the electric energy flow from the first to the second electric bus.