電気推進船における多数決待機冗長系の信頼性評価

抄録

Diesel-electric propulsion ship has attracted notice recently because the "QE2" was successfully modificated from steam-turbine. Diesel-electric propulsion has demerits such as heavier weight, more initial cost and fuel in comparison with diesel-geared. However diesel-electric propulsion is capable of wide ranged operation power, supplying both of propulsion and hotel survice power with one "power station", easy vibration isolation and the greatest reliability because of redundancy. In this article, we estimate availability of majority decision stand-by redundancy system on diesel-electric propulsion ship assuming stopped generators sets by troubles are not restored during a voyage. We could realise a ship of which diesel-electric propulsion system constructed by multi-generators sets were possible to supply normal power (85% of maximum power) for 30 days with availability more than 95% without restoration, if failure rate of a generator set were not more than 2×10^<-4> (event/hour). Of course, there are causes of machinery troubles on ship, such as low quality heavy fuel oil, that differ from contingent origins we consider in this paper.