摘要
电力变压器绕组故障诊断是保证电力变压器安全运行的关键技术。文中通过建立变压器有限元模型和高频等值电路模型,提出了基于"结构参数—电气参数—试验结果"诊断思路的变压器绕组故障诊断方法,可以有效提高电力变压器绕组故障诊断的可靠性。文中基于Ansoft Maxwell仿真平台建立变压器三维有限元模型,计算了变压器主要电气参数(对地电容、饼间电容等),分析了不同故障类型及故障程度下电气参数的变化。运用求解的电气参数搭建了高频等值电路模型,并由高频等值电路模型仿真对应试验结果。文中以轴向位移故障为例,仿真了不同轴向位移程度下变压器的频率响应试验曲线。建立了200~250 k Hz频率带上频率响应试验结果变化与轴向位移故障程度的拟合函数关系,通过该特征频率带上谐振峰的变化可以实现对轴向位移故障程度的诊断。提出的故障诊断方法为实现通过试验结果直接诊断变压器故障类型及其程度提供了参考。
Winding fault diagnosis of power transformer is the key technology to ensure the safe operation of power transformer. Combining the finite element method and the high-frequency equivalent circuit, a transformer winding fault diagnosis method is proposed in this paper. It can effectively improve the reliability of fault diagnosis based on the ideas of building a relationship betWeen structural faults, electrical parameters, and test results. Based on the finite element model built in Ansoft Maxwell, the main electrical parameters of the transformer, such as the frequency response analysis （FRA） under different fault degrees. The results of simulation shows that the change of the FRA curves at the selected frequency band （200~250 kHz） are by a cubic function and a parabolic function, respectively. It should tendency of FRA curves caused by axial displacement. Therefore, transformer winding fault diagnosis, and directly bridge the types and arranged along a curve which can be described be regarded as a diagnostic band to predict the the proposed diagnosis method can guide the degrees of the faults with the test results.
出处
《高压电器》
CAS
CSCD
北大核心
2018年第1期123-130,共8页
High Voltage Apparatus
关键词
电力变压器
有限元
绕组故障
径向形变
轴线位移
power transformer
finite element method
structural faults
radial deformation
axial displacement
