并列运行配电变压器分接开关异位时引发的事故分析

Analysis of Fault Due to Different Grades of Tap-changers for Distribution Transformers in Parallel Operation

为保证并列配电变压器的安全运行,杜绝并列运行配电变压器分接开关异位情况的出现,笔者对其分接开关异位时产生的环流及电流异常情况作了理论计算,分析引发的事故。对并列运行配电变压器分接开关异位,使配电变压器线圈产生循环电流,造成负载分配不匀,甚至会使变压器烧毁,提出了具体的防范措施,为防止发生配电变压器烧毁事故提供借鉴。

To guarantee parallel distribution transformers working safely and prevent tap-changers from different grades, theoretical calculation of the circulation current and the abnormal current due to different grades of tap-changers is conducted, and fault analysis is performed. The results show that different grades of tap-changers in parallel distribution transformers lead to circulation current in transformers coils to unbalance the load allocation, or even burn the transformers. Some measures to avoid the different grades are suggested.