Design and evaluation of a turbo-generator as an auxiliary power unit for hybrid vehicles

Hybrid powertrain technology is developing day by day and is proving more valuable than electric and fuel cell vehicles. The main focus of the paper is to understand the parametric design of the turbogenerator. The turbogenerator uses waste energy from the exhaust gases and converts it into electrical energy which is stored in the battery. The design strategy is developed in two phases and explained. The first phase is the turbine design in which the engine thermodynamic calculations for engine exhaust are performed. Based on the calculations, a new exhaust manifold is designed to optimise the performance of the turbogenerator. The second phase comprises the permanent magnet synchronous generator design in which the sizing of the hybrid powertrain is the primary aspect which also later becomes the boundary condition for the generator design. The turbogenerator is designed for a parallel hybrid powertrain which is compared to a turbocharged gasoline engine. This main aim for comparison of two engines is to illustrate the significance of hybrid technology having an auxiliary power unit.