BASIC POWER-SYSTEM RELIABILITY CONCEPTS

The basic function of an electric power system is to satisfy the system load requirements as economically as possible and with a reasonable assurance of continuity and quality. In order to achieve the required degree of reliability, power system managers, designers, planners and operators have utilized a wide range of criteria in their respective areas of activity. Initially all of these criteria were deterministically based and many of these criteria and associated techniques are still in use today. The basic weakness of deterministic criteria is that they do not respond to nor do they reflect the probabilistic or stochastic nature of system behavior, of customer demands, or of component failures. These factors can be incorporated in a probabilistic approach to electric power system reliability assessment and a wide range of techniques and criteria are available. This paper presents a summary of basic power system reliability concepts and briefly illustrates their application in system planning and design. © 1990.