Performance Benefits of a Portable Hybrid Micro-Gas-Turbine Power System for Automotive Applications

The lower fuel burn and pollutant emissions of hybrid electric vehicles give a strong motivation and encourage further investigations in this field. The know how on hybrid vehicle technology is maturing and the reliability of such power schemes is being tested in the mass production. The current research effort is to investigate novel configurations, which could achieve further performance benefits. This paper presents, an assessment of a novel hybrid configuration comprising a micro gas turbine, a battery bank and a traction motor, focusing on its potential contribution to the reduction of fuel burn and emissions. The power required for the propulsion of the vehicle is provided by the electric motor. The electric power is stored by the batteries, which are charged by a periodic function of the micro gas turbine. The micro gas turbine starts up when the battery depth of discharge exceeds 80% and its function continues until the batteries are full. The performance of the vehicle is investigated using an integrated software platform. The calculated acceleration performance and fuel economy are compared to the ones of conventional vehicles of the same power. The sensitivity of the results to the variation of the vehicle parameters such as mass, kinetic energy recovery and battery type is calculated to identify the conditions under which the application of this hybrid technology offers potential benefits. The results indicate that if no mass penalties are incurred by the installation of additional components the fuel savings can exceed 23%. However, an increase in the vehicle’s weight can shrink this benefit, especially in the case of light vehicles. Lightweight batteries and kinetic energy recovery systems are deemed essential enabling technologies for a realistic application of this hybrid system.