在多物理场下的变压器绝缘油中金属污染物颗粒的运动行为研究
Binbin Wei1, Zhijuan Wang1, Runze Qi1
1School of Electrical Engineering, Shangdong University, Jinan 250061, China.
Sensors (Basel, Switzerland)
|September 14, 2024
概括
变压器绝缘油中的金属杂质颗粒向高电场移动. 粒子大小和油质等因素显著影响它们的运动,有助于故障检测.
科学领域:
- 电气工程 电气工程
- 材料科学 材料科学 材料科学
- 流体动力学 流体动力学
背景情况:
- 变压器绝缘油对于介电性能至关重要.
- 变压器运行的金属颗粒会降低绝缘.
- 颗粒的移动显著影响内部绝缘的完整性.
研究的目的:
- 在各种电场条件下,研究变压器绝缘油中金属杂质颗粒的运动规则.
- 分析影响粒子运动的因素,包括大小,油流和油质.
- 为检测杂质颗粒和定位设备故障提供理论支持.
主要方法:
- 构建了一个多物理场模型,用于单个金属杂质颗粒的固体-液体两相流.
- 模拟不同电场环境中的粒子运动特征,使用动态分析.
- 在不同的粒子大小,油流速度和绝缘油品质下分析了运动特征.
主要成果:
- 金属杂质颗粒向高电场强度区域迁移.
- 粒子轨迹密度和碰撞频率随着电场强度和粒子大小的增加而增加.
- 增加的油流速度减少了粒子电极碰撞和聚合.
- 油的动态粘度下降 (由于温度或质量变化) 会导致更密集的轨迹,更多的碰撞和更高的速度.
结论:
- 电场分布决定了金属杂质粒子的轨迹.
- 粒子大小,油流速度和绝缘油质量是影响粒子动态的关键因素.
- 了解这些运动规则对于有效的变压器故障诊断和维护至关重要.
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