Study of Drawing Optimum Switch Automation Rate to Minimize Reliability Cost

신뢰도 비용 최소화를 위한 개폐기의 최적 자동화율 도출에 관한 연구

Chai, Hui-seok;Kang, Byoung-wook;Kim, Jin-seok;Moon, Jong-fil;Kim, Jae-chul

  • Received : 2015.11.16
  • Accepted : 2015.11.30
  • Published : 2015.12.01


Replacing a manual switch installed in a feeder for a distribution system with an automatic one increases the reliability of the electric power system. This is because the automatic switch can shorten the duration of a fault the customer experiences by splitting the faulty section faster than the manual one does. However, improving the reliability of the distribution system may increase investment costs. Here, the investment costs include automatic switch cost, replacement work cost and labor cost. For this reason, importance should be attached to the proper balance between the increase of the investment costs and the improvement of the reliability of the distribution system. This article analyzed reliability index and economics when manual switches installed in a feeder (RBTS Bus2 model) was replaced by automatic ones. In addition, it attempted to draw the optimum rate of automation of manual switches by automatic ones using the GRG optimization method, considering the current economic requirements.


Switch;Automation;Automation rate;Optimize;GRG method;Reliability;Reliability cost


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