Torsional dynamics of generator-units during autonomous operation

The main objective of this paper is to analyse dynamic behavior of diesel-generator units due to electrical loads and due to torsional strains on the shaft cable. A flexible coupling between generator rotor and rotating mass of diesel engine allows masses to rotate at a different speed in transient. In order to investigate the dynamic behavior of synchronous generator as well as torsional strains in the shaft line a unique mathematical model of integral motor drives has been developed. The model involves a prime mover, a synchronous generator with its electrical and mechanical properties and optionally, generator´s control system. Mechanical coupling of a prima mover and a synchronous generator is considered a rotating system with two concentrated masses allowing thus the analysis of the torsional dynamics in the coupling.