使用第一原理和马库斯理论计算电荷传输现象和隔热油中的移动性分析
Yuqi Chen1, Dayou Liu1, Mrutyunjay Maharana1
1State Key Laboratory of Electric Insulation and Power Equipment, Xi'an Jiaotong University, Xi'an 710049, China.
The journal of physical chemistry. B
|February 2, 2024
概括
这项研究调查了电力变压器绝缘油中的电荷转移. 由于分子轨道定位,电子转移明显比孔转移快,影响绝缘可靠性.
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:
- 油纸绝缘对于功率变压器的可靠性至关重要.
- 在老年绝缘油中,在分子水平上理解电荷传输是有限的.
- 石油绝缘的介电性质对于电力设备的运行至关重要.
研究的目的:
- 为了阐明在绝缘油中电荷传输的微观机制.
- 研究分子电子结构和电荷分布 (孔和电子).
- 为了确定电荷载体在各种条件下在绝缘油中的移动性.
主要方法:
- 对分子电子结构的第一原则计算.
- 马库斯理论的应用来计算合和重组能量.
- 蒙特卡洛模拟电荷移动性和电场下的电荷转移.
- 对自由能量计算的极化性和导电性的分析.
主要成果:
- 电子转移积分比孔转移积分大两个数量级.
- 最低的未被占用分子轨道 (LUMO) 定位解释了更快的电子转移.
- 电荷转移与马库斯跳跃和亚亚巴特模型保持一致.
- 在电场下模拟电荷移动性和传输图像.
结论:
- 这项研究提供了对绝缘油中电荷传输的分子层次理解.
- 这些发现提供了对油纸绝缘材料的介电性质和可靠性的见解.
- 识别的机制和移动性值对于预测绝缘性能和老化至关重要.
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