变压器有载分接开关故障案例分析及缺陷模拟试验研究

Fault Case Analysis and Defect Simulation of On load Tap changer in Transformer

摘要:

有载分接开关（OLTC）是实现变压器带载电压调节的关键设备，其可靠运行对于电网安全稳定具有重要意义。首先，以双过渡电阻组合式OLTC为例介绍了有载分接开关的典型结构和工作原理；然后，分析了3起典型故障案例，其中机械缺陷是导致OLTC故障的重要原因；最后，搭建了OLTC机械缺陷模拟平台，采用振动法开展了机械缺陷检测研究。结果表明不同状态下振动信号特征值变化，为后续OLTC状态评估提供了重要支撑。

Abstract:

On load tap changer (OLTC) is a crucial equipment for regulating the voltage of transformers under load, and its reliability is of great significance to the safe and stable operation of power grid. Firstly, the typical structure and working principle are briefly introduced by taking double transition resistance OLTC for example. And then, three typical accident cases are analyzed, which indicates that mechanical fault is an important cause of OLTC failure. Finally, a mechanical fault model for OLTC of 110 kV transformer is established, and vibration analysis method is adopted to study the mechanical fault. The results show that the vibration signal changes significantly under different conditions, which provides important supports for the subsequent state detection and evaluation of OLTC.