VIBRATION ANALYSIS FOR THE DESIGN OF A HIGH-SPEED GENERATOR FOR A TURBO-ELECTRIC HYBRID VEHICLE

The project relates to the design and development of a prototype high- speed turbo-generator as the thermal engine in a series hybrid vehicle . The substantial benefit of the turbo-generator against a diesel gene rator lies in the very high power-weight, power-volume ratio and rende rs itself particularly attractive for use in hybrid vehicle applicatio ns. However, to achieve a 50 kW power output, the turbo-generator has to have an operating speed of 60 000 r/min and thus important mechanic al problems have to be solved. The core of this study addresses the re quirement for an adequate understanding of rotor-dynamic behaviour by combining the results from both analytical and practical techniques. T he assessment of modal testing, finite element analysis and vibration- condition monitoring, their feedback within the design-make-and-test p rocedure and the practical compromises and design constraints are pres ented and a design methodology is formulated. It is concluded that, un der certain conditions, the prototype generator can be directly couple d to a small gas turbine, can operate safely and can produce the requi red power output.