Page 182 - Automotive Engineering Powertrain Chassis System and Vehicle Body

CH AP TER 7 .1 Hybrid vehicle design

Fig. 7.1-10 Gas turbine hybrid taxi: (a) package; (b) typical steady-state vehicle power consumption; (c) high speed disc alternator;
(d) system diagram of the TETLEI vehicle.

hybrid concept. This eliminates the feasibility of a small alternator which provides a large surface area for cooling
‘battery charger’ IC engine which is often proposed for from a relatively low volume machine, (c). The flux path
hybrid vehicles. is axial and is returned at the rotor ends by high strength
A key requirement of the researchers’ proposal is to steel keeper discs, the retainment ring being of carbon
produce a gas turbine at a price corresponding to an IC fibre. A key factor is that the rotor magnet retaining ring
engine while providing low fuel consumption over the is not between the magnets and the stator; the flux
medium to full power range. Tests are now under way at within the stator is consequently higher and the diameter
Imperial College on gas turbines of 30 and 50 kW; these of the rotor can be greater. This results in a compact shaft
are simple cycle machines but a recuperator is envisaged length suitable for high speeds. An induction motor used
for the larger engine. The generator envisaged is a disc with the system is considered to be the most reliable of

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