35kV并联干式电抗器故障缺陷分析

Fault Analysis of 35 kV Shunt Dry⁃type Reactor

通过诊断试验发现正常运行的35 kV并联电抗器存在匝间绝缘缺陷,处于带病运行状态。在现场、厂内分别对该电抗器进行直流电阻、电抗值、工频损耗、匝间绝缘、雷电冲击等试验,透过数据分析匝间绝缘缺陷逐步劣化的过程。并对缺陷电抗器进行解体,发现第8⁃3层存在典型湿污放电痕迹,与试验结论相吻合,分析外观爬电、击穿产生缺陷的原因。现有试验项目对发现匝间绝缘缺陷的灵敏性及原因分析。结合干式电抗器的运行环境、缺陷特征等因素,对其生产工艺、日常维护、检修试验项目选择等提出相关建议,确保能够及时发现干式电抗器潜在缺陷,防止带病运行,保障电网安全稳定运行。

In this paper,it is found through the diagnosis test that the 35 kV shunt reactor in normal opera⁃tion has inter⁃turn insulation defect and is in operation state with fault.Such tests as DC resistance,reac⁃tance,power frequency loss,inter⁃turn insulation and lightning impulse are performed on the reactor respec⁃tively at site and factory,and the gradual deterioration process of the inter⁃turn insulation defects is ana⁃lyzed through data analysis.It is found after the disassembly of the reactor with defect that there are typical wet contamination discharge traces on the 8⁃3 layer,which is consistent with the test results.The causes of appearance creepage and breakdown are analyzed.The sensitivity and cause analysis of the existing test items to find inter⁃turn insulation defects is displayed.In combination with such factors as the operating en⁃vironment and defect characteristics of the dry⁃type reactor,relevant suggestions for its production process,routine maintenance,maintenance and test item selection are proposed as to ensure that the potential de⁃fects of the dry⁃type reactor can be found in time,prevent the operation with defects,and assure safe and sta⁃ble operation of the power grid.