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Modern hybrid technologies, especially mild and micro-hybrids with auto start/stop feature, demand a starter with higher power, better performance and longer life than conventional brush-type starters. In this paper, a new starter design using a brushless motor is proposed. This improves the engine crank performance during autostarts due to lower inertia, higher torque and wider power band capability of the brushless motor, especially at higher speeds. The overall integrated system includes the motor, inverter and controller all packaged in the same form factor of the original starter housing as a “drop-in replacement”. The prototype starter motor is designed to operate at 48V with a peak power of 4kW but can be designed to operate at the standard 12V. This paper will describe in detail the functionalities of the overall system and the simulation and experimental results of the prototype that was tested on a 4-cylinder engine in a production crossover vehicle.

In this paper, a low-cost means to improve fuel economy in conventional vehicles by employing ultracapacitor based Active Energy Recovery Buffer (AERB) scheme will be presented. The kinetic energy of the vehicle during the coast down events is utilized to charge the ultracapacitor either directly or through a dc-dc converter, allowing the voltage to increase up to the maximum permissible level. When the vehicle starts after a Stop event, the energy stored in the capacitor is discharged to power the accessory loads until the capacitor voltage falls below a minimum threshold. The use of stored capacitor energy to power the accessory loads relieves the generator torque load on the engine resulting in reduced fuel consumption. Two different topologies are considered for implementing the AERB system. The first topology, which is a simple add-on to the conventional vehicle electrical system, comprises of the ultracapacitor bank and the dc-dc converter connected across the dc bus.

This paper describes a Magneto-Rheological coupling based Hydraulic Power Steering (MRHPS) system developed for improving fuel economy in conventional vehicles. The MRHPS system reduces the parasitic losses associated with the power steering pump and improves fuel economy in full-size trucks (and SUVs) by up to 3%, while maintaining the production hydraulic power steering system performance. The MRHPS is a low cost alternative to electric power steering and electro-hydraulic power steering systems and requires significantly less electric power while resulting in similar fuel economy gains. With the MR coupling the power steering pump is run at optimum speeds depending on the steering angle, angle rate and vehicle speed, and the pump is run in closed loop speed control mode so that factors like temperature, manufacturing tolerances, aging, etc. will not degrade the steering performance.