Author(s)

G. Martinelli, A. Morini & A. Tortella

Abstract

This paper presents the development status of the innovative technologies adopted for urban electric transport systems. The description is mainly focused on the zero emission buses based on fuel cells and energy storage devices such as supercapacitors and batteries. These vehicles are characterised by higher operating range and efficiency than hybrid and battery buses and don’t need an external supply. The features of the on-board supply system, of the control strategy and of the drive configuration are presented with reference to the guidelines developed in a national research project involving four Italian universities. A detailed analysis is given about the choice of the type of electric motor, as it directly affects the vehicle performance and the drivetrain efficiency; in particular, three in-wheel permanent magnet motors are compared in terms of installation requirements, torque production and total weight. Keywords: electric transport systems, fuel cell vehicles, energy storage devices, in-wheel motors, permanent magnet motors. 1 Introduction The increase of the air and noise pollution which has nearly reached and often exceeded the safety limits also in the mid-size cities requires the adoption of new technological solutions for the urban transport systems with low environmental impact. The need to reduce the traffic of private cars calls for the realisation of innovative public transport systems which must ensure a good level of comfort and efficiency with very low emissions and reduced noise and vibrations. The introduction of new fuels (biodiesel, demineralised water emulsions, methane etc.) as partial or complete replacements of diesel fuel for buses propelled by only an internal combustion engine (ICE), leads to a limited decrease of the

Keywords

electric transport systems, fuel cell vehicles, energy storage devices, in-wheel motors, permanent magnet motors.