Reliability and quality comparisons of electric power distribution systems

The design and operating parameters of seven common distribution systems are examined to compare their performances in terms of reliability and power quality. Field experience is matched with theoretical calculations for frequency and average duration of outages in order to predict relative reliability levels that can be expected from each type of system. The systems are then ranked by reliability and their ability to supply what has come to be known as clean power. The result provides a basis of comparison for the distribution engineer when choosing the system design suitable for the particular type of load to be served