Preventive maintenance scheduling in power generation systems using a quantitative risk criterion

Consideration of maintenance scheduling of generating units is an important aspect in the development of an optimum generation system expansion plan. This consideration will become even more important as the move towards large fossil and nuclear units continues. Maintenance scheduling should permit the required work to be accomplished but not create excessive risk to the system. The problem can therefore be considered in terms of levelizing the system risk throughout the year and this approach is designed as the risk levelization technique. Another way of considering the problem of generating unit maintenance scheduling is to levelize the amount of reserve throughout the year. This technique therefore, is, designated as the reserve-levelizing approach. Both techniques are used in this paper and a comparison between them is presented. The effect on maintenance scheduling of changing the system hourly peak demands and the availability of generating units have been studied and are also presented. These studies are based on the Gram Charlier series of Edgeworth Form.