摘 要

我国高电压等级电力系统的改造和扩建正处于高速发展时期，直流输电技术兴起，且正在逐步取代交流输电的地位，拥有广阔的应用前景，但目前其发展受到直流偏磁危害的限制，急需高效的抑制方案以及科学的监测手段。平波电抗器在电力系统中承担整流滤波的功能，同时受直流偏磁影响升温现象明显。就目前的研究现状而言，国内外对平波电抗器的温升监测以及温度场计算的研究较少，而其中干式平波电抗器对外界环境产生的污秽较敏感，且在工程应用中，对发热点和红外的测温也较为困难。因此，电抗器绕组温升的仿真建模具备一定的研究意义。本文在介绍直流输电技术发展现状、直流偏磁相关危害及计算方法的同时，以某500KV干式平波电抗器为主要研究对象，分析了干式平波电抗器的基本结构，并依照结构建立简化模型，借助建模软件Comsol，利用有限元法，模拟了直流偏磁的环境，并对包封绕组部分进行了仿真建模，以研究其在直流偏磁情形下的温升表现是否符合规定。通过观察温度场、流体场的分布情况，对该款干式平波电抗器进行了分析总结，研究结果表明，该款电抗器即使在直流偏磁情况下也能保持正常运转，但缺乏一定裕度，需依据有关条件进行改进。

最后，论文根据计算结果以及相关文献内容进行归纳，提出了一些电抗器的改进建议和未来应该重点研究的方向，具有一定参考价值。

关键词：电抗器；直流偏磁；变压器；直流输电；温度场

Abstract

High voltage grade of power system reform in our country and expansion in the period of rapid development, dc transmission technology, and is gradually replaced the status of the ac power, has broad application prospects, but at present, the development is limited by dc bias hazard, inhibition in urgent need of efficient and scientific means of surveillance. The flat wave reactor has the function of rectifying the rectifier in the power system, and it is obvious that the effect of the dc deflection is obvious. In terms of the present research status at home and abroad of the flat wave reactor monitoring of the temperature rise and the temperature field of study is less, and the dry flat wave reactor produces filthiness is more sensitive to the external environment, and in engineering application, to send hot and infrared temperature measurement is also more difficult. Therefore, the simulation modeling of the windings of reactor windings has certain research significance. Dc transmission technology development present situation, this paper introduces the dc bias related harm and at the same time, the calculation methods of taking a 500 kv dry-type hollow flat wave reactor as the main research object, the basic structure of dry flat wave reactor are analyzed, and the simplified model is established according to the structure, using modeling software Comsol, using the finite element method, simulates the dc bias of the environment, and the coating winding part has carried on the simulation modeling, to study its performance in the rise of temperature of the dc bias case is in line with the regulations. By observing the distribution of temperature field, fluid field, in the dry flat wave reactor are analyzed and summarized, the research results show that the reactor is even in the case of dc bias can maintain normal operation, but the lack of a certain margin, improvement should be carried out according to relevant conditions.

Finally, the paper according to the calculation results, summarized the content and related literature, puts forward some Suggestions for improvement of reactor and the future should focus on the research direction, has certain reference value.

Key Words：reactor；DC magnetic blasing；transformer；Dc power transmission；The temperature field

目 录

摘 要 I

Abstract II

第1章 绪论 1

1.1 选题的背景与意义 1

1.2国内外研究现状 2

1.2.1一些抑制直流偏磁方法的研究 2

1.2.2平波电抗器的开发与应用 3

1.3课题的研究内容 6

第2章 直流偏磁影响下的分析计算 8

2.1 研究概况 8

2.2偏磁实验 8

2.3 计算分析 9

2.3.1迭代法 9

2.3.2 EMD分解与Hibbert变换 10

第3章 电抗器温度场的建模仿真 12

3.1介绍 12

3.2 模型定义 12

3.2.1 数学模型 13

3.2.2 假设条件 13

3.2.3边界条件 13

3.2.4 网格模型 15

第4章 分析与讨论 18

4.1 结果分析 18

4.1.1温度场分析 18

4.1.2流体场分析 19

4.2 进一步研究方向 19

第5章 结论 21

参考文献 22

致 谢 25

第1章 绪论

1.1 选题的背景与意义

直流输电技术的发展已有百余年历史，可以说伴随电力系统的产生，直流输电技术的概念就被人提出，但因受当时工业水平所限，直流电机的串接运行十分复杂，直流输电技术的发展受到制约，无法与后来出现的交流输电技术展开竞争。而随着电力行业的发展，以及人民日益增长的电力需求，具有输送距离长、成本低这些优势的直流输电技术，自二十世纪九十年代再度发展起来，至今国内外已取得了一系列研究进展^[1~4]， 但现今常规的直流输电技术依然被一些难以完全解决的问题、如直流偏磁现象所困扰^[5~6]，电抗器作为直流输电技术中，电力系统的重要组成部分，因直流偏磁影响所发生的温升现象，本文主要探讨的研究内容^[7]。