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On the basis of the advantages of heat efficiency and
mechanicals principles , the turbine generator is more
adapted to large power system than other kinds of generators.
The advances of apparatus and production techniques result in
the production of larger generator set with a lower
construction and operation cost per unit .However, limited
to the material development difficulty, each essential factor
no longer keeps up safety factor as it did before. The blades
of shafts and low pressure turbine section have sustained
great stress in normal operation . If the generator set is
in electrical distribution or resonance conditions , the
increasing stress might cause material fatigue. The loss of
accumulated fatigue will cause shafts' damage and even
severe incidents and disadvantages . This dissertation
begins with the theories of the combination of each field and
relative records, and sets up a complete model by combining
power system , control systems, and mechanical system .
Generally , shaft vibration analysis restricted only to
single set or double set power system can not completely
explain practical complicated power system phenomena. In order
to realize the influence caused by the interaction among
generators during , when the incidents take place, we expect
the established multimachines system model could arouse more
practical reflection in system analysis. The analysis
principles mentioned in this dissertation can offer an
important feature in the assessment of machine system design,
pre-commissioning test appraisals and post-event damage
diagnose . The various breakdown of power system network,
switch operation , generator trip , and load rejection are
included in the simulation . These analysis principles are
effective in system dynamic simulation analysis and offer
strong basis for advanced research.
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