Published in FOREX-IJEER

Impact of System Average Interruption Duration Index Threshold on the Reliability Assessment of Electrical Power Distribution Systems

ABSTRACT

System Average Interruption Duration Index (SAIDI) is one of the parametric indices used for assessment of the performance of electrical power network. It is the ratio of customers’ interruption duration to the total number of customers served. SAIDI threshold is used to determine the calendar days upon which either the system design limits or operational limits are exceeded. This research paper presents the impact of SAIDI threshold on the reliability assessment of electrical power distribution system. Data were collected from ten selected feeders of Ibadan distribution system for a period of five years. The daily SAIDI, natural logarithm of SAIDI, the log-average of SAIDI and the standard derivation of the logarithm of SAIDI were used as input parameters in the development of SAIDI threshold model. The result of the research paper shows that the SAIDI threshold values fluctuate over the years with the least and highest SAIDI threshold values as 2.11596 and 4.62518 respectively which were recorded in the months of September and April. The SAIDI thresholds in the months of January, February, March, April, May and June are 3.18318, 3.32458, 4.22242, 4.62518, 2.71360 and 3.27760 respectively suggesting an indefinite pattern in the SAIDI threshold as a result of unexpected interruptions experienced by customers attached to the distribution feeders. SAIDI threshold forms a basis for power system planning and maintenance strategies.

Keywords: SAIDI, Electrical power distribution systems, Threshold, SAIDI Threshold, Reliability, Interruption, Momentary interruptions.

Author(s): Ganiyu Adedayo Ajenikoko, Ridwan Abiola Oladepo