基于分子动态的液晶改性天然绝缘油的介电性能的微机理研究
Yizhou Jiang1, Zhengyong Huang1, Jian Li1
1State Key Laboratory of Power Transmission Equipment & System Security and New Technology, School of Electrical Engineering, Chongqing University, Chongqing 400044, China.
The Journal of chemical physics
|April 22, 2025
概括
液晶通过提高分解强度和抑制电气问题来增强天然绝缘油的介电性能. 这种新的方法为修改电力设备中绝缘油提供了一种稳定,有效的方法.
科学领域:
- 材料科学 材料科学 材料科学
- 电气工程 电气工程
- 物理化学 物理化学
背景情况:
- 天然 (NE) 绝缘油是电力设备的首选选择,因为它的高点燃点和生物降解性.
- 提高NE的介电性质对于先进的高压电力系统至关重要.
- 纳米粒子提供介电增强,但分散稳定性差,限制了实际使用.
研究的目的:
- 调查液晶作为修改NE绝缘油的新型功能材料的使用.
- 分析液晶对NE介电性质增强背后的微观机制.
- 评估液晶对交流电断裂强度和NE部分放电抑制的影响.
主要方法:
- 用不同的液晶质量分数修改的NE的实验测试.
- 分子动力学模拟用于在修改前后对油分子进行建模.
- 密度函数理论原理用于分析微观相互作用和机制.
主要成果:
- 液晶的0.3%质量分数显著增加了16.7%的NE的交流分解强度.
- 观察到液晶分子减少了系统的自由体积,并通过结合阻碍了水的扩散.
- 液晶有效捕获自由电子,减少载体的移动性,抑制部分放电和电化学反应.
结论:
- 液晶代表了一种有希望的功能材料,用于增强NE绝缘油的介电性质.
- 微观机制涉及自由体积减小,阻碍水的扩散,并通过液晶捕获电子.
- 这种修改提供了一种稳定有效的策略,用于提高高压应用中NE的性能.
相关概念视频
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When an electric field passes from one homogeneous medium to another, crossing the boundary between the two mediums imparts a discontinuity in the electric field. This results in electrostatic boundary conditions that depend on the type of mediums the field propagates through.
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Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.


