Evaluation of the Reliability of Distribution Power Systems Considering Composite Customer Interruption Cost

  • Choi Sang-Bong (Underground Power System Group, Power System Division, KERI) ;
  • Nam Kee-Young (Underground Power System Group, Power System Division, KERI) ;
  • Kim Dae-Kyeong (Underground Power System Group, Power System Division, KERI) ;
  • Jeong Seong-Hwan (Underground Power System Group, Power System Division, KERI) ;
  • Lee Jae-Duk (Underground Power System Group, Power System Division, KERI) ;
  • Ryoo Hee-Suk (Underground Power System Group, Power System Division, KERI)
  • Published : 2005.09.01


As the power industry moves towards open competition, there has been a call for methodology to evaluate power system reliability by using composite interruption cost. This paper presents algorithms to evaluate the interruption cost of distribution power systems by taking into consideration the failure source and the composite customer interruption cost. From the consumer's standpoint, the composite customer interruption cost is considered as the most valuable index to estimate the reliability of a power distribution system. This paper presents new algorithms that consider the load by customer type and failure probability by distribution facilities while calculating the amount of unserved energy by customer type. Finally, evaluation results of unserved energy and system interruption cost based on composite customer interruption cost are shown in detail.


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