Hybrid Electric Turbocharger For Exhaust Energy Recovery and Transient Lag Reduction

The U.S. economy and the American way of life rely heavily on transportation by cars and trucks. This transportation is dependent almost entirely on oil, which creates vulnerability to supply chain disruptions, potential for fuel price shocks, and exposure to emissions of air pollutants. Reducing vehicular fuel consumption is critical for sustaining U.S economic and environmental wellbeing. Mainstream Engineering is proposing a hybrid electric turbocharger (HET/C) that incorporates an integrated motor/alternator onto the turbocharger shaft capable of generating electrical power at high speed/load conditions, improving transient response (turbo lag) during acceleration events, and broadening the effective range of the turbo. The HET/C leverages multiloop control and advanced motor/alternator/shaft design to overcome thermal, lubrication, and rotor dynamic challenges. The overall objective is to demonstrate a productionready prototype at the conclusion of Phase II that exceeds DOE targets for fuel economy, operating range, and cost. Commercial Applications The market size for automotive turbochargers is large and growingthe global market size was approximately $1.9B in 2010 and is expected to grow to $2.9B by 2015. Taking advantage of the trend towards downsized turbocharged engines, Mainstream Engineering seeks to provide a nextgeneration experience.