Abstract
The phenomenon of electrical disturbance induced shaft torsional stressing of large turbine-generators has received considerable attention during the last two decades. In most of reported studies in this area, the main concern was to evaluate the effect of network and system components electrical disturbances on turbine-generator shaft torsional system. Fewer studies have, however, investigated the mechanical impact on turbine-generator shaft sections. The main objective of this paper is to extend the evaluation procedure to calculate the expected life expenditure ratio and the expected shaft lifetime of different turbine-generators shaft sections. In this approach, a Monte-Carlo simulation technique is used to evaluate the maximum turbine-generator shaft torsional torques considering the uncertainties associated with system faults and faulty synchronization.