Generating Unit Maintenance Scheduling for Single and Two Interconnected Systems

Probability methods have been applied to schedule generating unit maintenance in single systems. Many utilities are now firmly interconnected with neighbouring utilities and generating capacity planning is conducted on a fully or semi-integrated basis. This paper presents a method based on the Gram-Charlier expansion for evaluating maintenance schedules in two interconnected power utilities using a levelized reliability criterion. This paper also investigates the effect of changing one utility peak demand on the maintenance schedule of the other utility. It also investigates the influence of tie capacity on the maintenance schedule of both utilities. An extention to the concept of the effective load carrying capability (ELCC) of a unit from single to two interconnected systems has been illustrated in this paper. Although the method has been applied to two interconnected systems, there are no conceptual difficulties in extending it to multi-interconnected systems.