采用全寿命周期成本与风险分析的 农村配电变压器更换投资策略
Replacement and Investment Strategy for Distribution Transformers in Rural Area Based on Life Cycle Cost Theory and Risk Assessment

农村现有的10 kV配电变压器由于老化问题已经难以满足逐年增长的用电需求,变压器更换已成为农村配网改造中亟待解决的重要问题。为此,提出了一种基于全寿命周期成本与风险分析的老化变压器更换决策新方法。该方法在分析变压器全寿命周期各项成本的基础上,综合考虑服役时间、供电可靠率、重载负荷等因素对变压器经济寿命的影响,并结合投资风险评估思想安排老化变压器的更换次序,弥补了传统决策方法中仅以服役时间作为主要投资依据的不足。以陕西南部地区某农村配网中9台变压器的更换为例进行了计算,结果表明:所提方法能够在变压器更换方案中反映低供电可靠率、重载负荷对变压器经济寿命的负面影响,较仅以服役时间为依据的传统方法更为科学有效;此外,采用文中提出的变压器更换投资决策方法减少了2.93％的更换成本,显著提高了变压器更换投资的经济效益,能够为农村配电变压器的投资规划提供参考。
The current 10 kV distribution transformers in rural area can hardly satisfy the gradually increasing power demand due to the aging？？failure. Facing this challenge, a novel decision approach for the replacement of aged transformers is developed with life cycle cost theory and risk assessment. The proposed approach considers the impacts of operating time, supply reliability and heavy load to transformer economic life, which remedies the limitation of the conventional approach. Furthermore, the methodology based on risk assessment is also utilized in the final investment strategy. A replacement order for nine aged transformers of a rural distribution network in southern Shaanxi is arranged. The numerical results indicate that the proposed approach enables to make a more reasonable investment decision and to reflect the adverse impacts of poor reliability and heavy load on the economic life of transformers. This approach improves the cost？？effectiveness of transformer replacement by reducing 2.93％ of the total cost