一起变压器故障追踪分析

Tracing Analysis of Transformer Faul

电力变压器是输变电设备中的重要设备之一,变压器故障将直接影响电网安全稳定运行。通过一起变压器层压木内部存在气隙引起的绝缘击穿故障,采用长时感应电压带局部放电试验、绝缘油色谱分析、绝缘材料组分检测、模型试验验证等试验检测手段,结合MAXWELL和MPCCI模拟仿真技术,研究分析了层压木内部存在气隙(气泡)的大小、位置和形状与电场强度和电压分布间的关联性。研究结果表明:气泡的体积越大对其周围电场畸变的影响越严重,气隙(气泡)距离电极越近,电场强度畸变越大。

The power transformer is one of the important equipment in the power system,and the failure of transformer will directly affect the safe and stable operation of power grid.Through a case of breakdown failure caused by the existence of air gaps in the laminated wood of transformers,the correlation between the size,location and shape of the air gap(bubble)existing inside the laminated wood and the electric field strength and voltage distribution is studied and analyzed by using test and inspection means such as long-time induced voltage with partial discharge test,insulating oil chromatog-raphy analysis,insulation material component detection and model test verification,com-bined with MAXWELL and MPCCI simulation technology.The results show that the larger the volume of the bubble the more serious the effect of the electric field distortion around it,and the closer the air gap(bubble)is to the electrode,the greater the elec-tric field intensity distortion.