基于瞬时电位加载法的±800kV特高压阀厅金具表面电场求解  

Surface Electric Field Calculation of Fittings Inside ±800 kV Valve Hall Using Electrostatic Field Instantaneous Load Method

作　　者：杜志叶[1] 朱琳[1] 阮江军[1] 金硕[1] 胡龙飞[1] 常林晶 

机构地区：[1]武汉大学电气工程学院,武汉430072 [2]平高集团有限公司,平顶山467000

出　　处：《高电压技术》2014年第6期1809-1815,共7页High Voltage Engineering

基　　金：国家重点基础研究发展计划(973计划)(2011CB209404)~~

摘　　要：换流站阀厅内部结构复杂,各部位的电位呈现非正弦周期性变化,通过瞬态场进行电场求解计算量过大,难以实现金具表面电场计算。为此,通过对阀厅主设备电位波形的分析,结合厅内电磁场的特点,提出了基于静电场的瞬时电位加载法。通过简单2维模型验证了该方法的正确性。以某±800 kV特高压阀厅为例,建立了3维有限元模型,实现了阀厅内部金具表面电场的准确求解。计算结果表明:所选阀厅内部最大电场强度为1.267MV/m,出现在D侧C相换流变压器套管均压球上,参考对应的试验值和裕度值,该值仍小于对应的起晕电场强度控制值1.589 MV/m,说明裕度充分,符合安全运行的要求。该方法解决了阀厅模型瞬态场计算量大,难以实现金具表面电场计算的问题,对于阀厅的内部电场的计算以及金具的设计具有重要的指导意义。It is hard to calculate the surface electric field of fittings inside a valve hall in a converter station through transient analyses, since the complex structure of the valve hall results in non-sinusoidal periodical filed distribution. To overcome this problem, after analyzing the voltage waveforms of the main equipment, and taking the features of the electromagnetic field inside the valve hall into account, we proposed an instantaneous load method of the electrostatic field and verified it with a simple 2-D model. Then we were able to accurately solve the surface electric fields of the fittings in a 3-D valve hall model, which was built according to a ±800 kV UHVDC valve hall. The results reveal that the maximum surface electric field intensity of the fittings is 1.267 MV/m, and it appears on the shielding ball at the top of phase C lower bushing in D side. According to the corona experiment data and a certain margin, the corona control electric field of the shielding ball is 1.589 MV/m, higher than the maximum value. This indicates that the fittings are free from corona under working condition. The proposed method overcomes the problem of over-large computing amount in transient analyses, and it is of guiding significance to the field calculation and the fitting design of valve halls.

关 键 词：特高压直流 阀厅 电位波形 电场计算 有限元法 瞬时电位加载法 

分 类 号：TM721.1[电气工程—电力系统及自动化]