Estimation For Life Cycle Cost Of Overhead Lines

With the development of theoretic studies in life cycle cost management, its application fields are extended from the military area to the civilian and other areas. The present power system in our state the concept of life cycle cost management was introduced by Shanghai Power Grid Company since 2004. The estimation and analysis for life cycle cost is the very core of life cycle cost management. Therefore, it is significant to study on the theories and methods of life cycle cost estimation of power grid assets.First, the paper elaborates on the concept and domestic and overseas research status and application of life cycle cost. Research status of life cycle cost estimation theory is elaborated in succession, and methods of estimation for life cycle cost are examined.With the breakdown of product structure, costs structure and life cycle for power grid assets, the paper establishes a three dimensional cost estimation model of life cycle cost. Based on the characteristics of overhead lines, the model used to estimate for life cycle cost of overhead lines is established, and is applied to LineⅠof GuNan in Hebei Power Grid. With accumulation of cost element in the life cycle cost model of overhead lines., target costs are obtained. The result shows that the main costs of life cycle cost for overhead lines occur in the operation and maintenance phase, where the line loss cost is the main cost, and the reliability of overhead lines should be determined by comprehensive consideration between initial cost and operation and maintenance cost.By the method of probability analysis, the paper also analyzes the uncertainties in the result of the estimation for life cycle cost of overhead lines.Monte Carlo simulations are made for the cost estimation with the tool of Crystal Ball, from which the probability distributions and statistical characteristics of the simulation results are obtained, showing the reliability for the estimation result.The main conclusions and some questions for further research are proposed at the end of the paper.