闫志强,雷 霞,何建平,周卫华,叶会生,赵莉华.三相不平衡对配电变压器带负载能力的影响研究[J].电测与仪表,2018,55(8):51-57. Yan Zhiqiang,Lei Xia,He Jianping,Zhou Weihua,Ye Huisheng,Zhao Lihua.Study on the influence of three-phase unbalance on the load capacity of distribution transformer[J].Electrical Measurement & Instrumentation,2018,55(8):51-57.
三相不平衡对配电变压器带负载能力的影响研究
Study on the influence of three-phase unbalance on the load capacity of distribution transformer
In distribution network, three-phase unbalanced operation are widespread. This will cause the problem of single-phase overload about distribution transformer, and then lead to the increase of loss and rise the hot-spot temperature. As a result, the aging rate of insulation is accelerated and has a great influence for the life of the transformer and the load capacity. In this paper, the calculation model of hot-spot temperature under off-center operation of distribution transformer is deduced. Then the overload capacity of the distribution transformer is evaluated based on the limit of hot-spot temperature and the allowable overload factor. Finally, the constraint conditions of each load type are given. This paper provides a reference for the safe and economical operation of oil immersed distribution transformers in power grid.
