The Low Emission Turbogas Hybrid Vehicle Concept-Preliminary Simulation and Vehicle Packaging

The paper presents a comprehensive review of the gas turbine hybrid vehicle (GTHV) under development at the University of Roma "Sapienza." A GHTV is an electric vehicle (traction entirely electric on 1 or 2 axles) equipped with a small turbogas operating as a range extender and -when needed- as a recharger for other auxiliaries. After a brief review of the history of the GTHV technology, a few configurations proposed in the past by different Authors are described and critically analyzed. Then, a complete feasibility assessment of a prototype configuration of a GTHV is presented and discussed in detail. Two possible implementations are studied: one for a small city car (peak power 4-8 kW) and one for a sport GT or passenger sedan (50-100 kW). All issues related to the system and component design, packaging, identification of the "optimal" hybridization ratio, performance of the conversion chain (gas turbine+batteries+electrical motor), kinetic energy recovery systems (KERS), mechanical and electric storage devices (flywheels, capacitors, advanced batteries), monitoring and control logic, compliance with the European vehicular ECE emission regulations, are explicitly addressed. One of the most important results of this analysis is though that there are several "nearly optimal" solutions and the final choice for a possible future industrialization would be dictated by manufacturing, commercial or marketing considerations. It because not only the system performance, but also the absolute and relative sizes (i.e., nameplate power) of the turbines and of the battery package depend substantially on the type of driving mission the car is required to perform. In the paper, both theoretical and practical issues are addressed, and on the basis of the analysis of the existing state of the art, it is argued that the GTHV is an environmentally friendly, technically and economically feasible product based on mature components.