确定变压器更换策略的机会成本方法

An Opportunity Cost Method Based on Replacement Strategy for Transformers

准确评估变压器的经济寿命,不仅对于适当安排其运行方式进而实现其安全与经济运行具有重要作用,也是确定变压器更换策略的依据。针对变压器全寿命周期内的故障率的特征,以常用于描述变压器温升老化失效的Arrhenius-Weibull模型为基础,提出了模拟其故障率浴盆曲线损耗故障期的新方法,并引入变压器役龄回退因子来表征变压器检修的效果。接着,通过综合考虑检修和更换变压器的经济要素,可求得相应的机会成本。最后,以检修和更换变压器的机会成本作为判据来确定变压器的最佳更换时机,并用算例结果说明了所提出的方法的基本特征。

Accurately evaluating the economic life of a transformer not only plays an important role in appropriately scheduling its secure and economic operation, but also provides the basis for determining its replacement strategy.Considering the characteristics of the transformer failure rate in its life cycle,the Arrhenius-Weibull model which is widely employed for describing the transformer temperature aging failure is firstly presented to model the loss failure stage in the failure rate bathtub curve. And a transformer age reduction factor is introduced to characterize the effect of transformer maintenance. Then,the opportunity costs are calculated through comprehensively considering the economic factors of the transformer maintenance and replacement. Finally,the opportunity costs of the transformer maintenance and replacement are used as the criteria for determining the optimal replacement timing of the transformer. A sample example is served for demonstrating the essential features of the presented method.