Schacht, H., Schoegl, O., Bretterklieber, N., Kirchberger, R. et al., "Low Cost Range Extender Technology for Hybrid Electric City Scooters," SAE Technical Paper 2012-32-0083, 2012, doi:10.4271/2012-32-0083.
Electric driving is generally limited to short distances in an emission sensible urban environment. In the present situation with high cost electric storage and long charging duration hybridization is the key to enable electric driving. In comparison to the passenger car segment, where numerous manufacturers are already producing and offering different hybrid configurations for their premium class models, the two wheeler sector is not yet affected by this trend. The main reason for the retarded implementation of this new hybrid technology is its high system costs, as they cannot be covered by a reasonable product price.Especially for the two wheeler class L1e, with a maximum speed of 45 km/h and an engine displacement of less than 50 cm₃, the cost factor is highly important and decisive for its market acceptance, because the majority of vehicles are still low-cost products equipped with simple carbureted 2-stroke engines.Hybridization of this vehicle class is therefore a very cost-sensitive task and enforces low-cost solutions.The present paper (within the framework of the ECO-PowerDrive project conducted at the Institute of ICE, research area design, located at Graz University of Technology) assesses a hybridization concept with range extender. Special emphasis is put on the interaction of the main components - generator and combustion engine - in order to deduce specifications. The application of a simple port-scavenged two-stroke engine is evaluated on the basis of experimental data and simulation results with respect to the principles of economy, emissions and consumption.Part reduction and system simplification are the keys for a suitable cost-efficient hybrid system.