【作者】 赵智亮；

【导师】 舒立春；

【作者基本信息】 重庆大学 ， 电气工程， 2003， 硕士

【摘要】 高海拔地区相对空气密度较低，绝缘子和空气间隙的放电特性与低海拔地区有很大的差异。这种差异一直是电力系统外绝缘设计的关键问题之一。海拔2000 m以下地区的大气参数对外绝缘放电电压的影响在GB/T16927.1和IEC60.1中规定了校正方法。目前国内外标准中尚未建立海拔2000～4000 m地区大气参数对放电电压影响的标准校正方法，但许多研究者根据各自的试验条件提出了不同的校正方法。而到目前为止，对海拔4000 m以上地区大气参数对外绝缘放电影响的研究国内外尚未见报道。因此，结合西部大开发的重点工程建设需要，论文选择海拔4000 m以上大气条件下空气间隙和绝缘子放电特性作为研究课题，具有重要的工程应用价值和学术意义。在国内外研究的基础上，论文以青藏铁路27.5kV和35kV系统为目标，在人工气候室内模拟海拔4000 m以上地区的大气条件，对小于500 mm的“棒－板”典型空气间隙和绝缘子短串的工频、雷电和操作冲击放电特性进行了试验研究。根据试验研究结果分析了海拔4000 m以上大气条件下“棒－板”短空气间隙和绝缘子短串分别在三种电压作用下放电特性，并提出了放电电压的校正方法。论文的研究工作和成果主要有：“棒－板”典型间隙和绝缘子短串的放电电压均随海拔的升高而降低，且其降低的趋势与海拔高度的范围有关，海拔越高降低的速度越缓慢。气压的变化反映了海拔高度的变化及其相应海拔下空气温度、湿度和相对密度的变化。气压可作为表征海拔高度对外绝缘放电电压影响的特征参数；高海拔地区空气间隙和绝缘子串的放电电压U均可表示为相应海拔下气压的幂函数，即U=U0(P/P0)n，其中气压对放电电压影响的特征指数n与电压类型和放电间隙的结构类型以及绝缘子类型等有关。论文还初步分析了高海拔大气条件下“棒－板”短空气间隙和绝缘子短串放电电压随气压降低而降低的基本机理。论文的研究结果为正在建设中的世界上海拔最高的青藏铁路供电系统的建设以及其它海拔4000 m以上地区外绝缘的设计提供了试验数据和理论支持。更多还原

【Abstract】 The relative air density decreases with the increasing of altitude. Therefore, the discharge performance of air-gap and insulator string at high altitude regions is different from that of the referring standard conditions. This difference is one of the key question in the design of the external insulation. It is put forward that the correction of external insulation discharge voltage for the region 2000 m and below in GB/T16927 and IEC60.1. In spite that there is no unanimous voltage correction method in the region between 2000 m and 4000m, a number of investigators both at home and abroad have put forward some voltage correction method of external insulation, which should be applied in corresponding conditions. Up to new, it is no report that the correction of effect of atmospheric condition on discharge voltage of external insulation is studied in the region 4000 m and above. So, based on the important project, the discharge performance of short rod-plane air gaps and short insulator strings has been researched in this dissertation, which there is not only very important value of engineering application but also very important value of learning.Based on the result of study both at home and abroad, aimed at 27.5 kV and 35 kV power supply system of on-going Qinghai-Tibet railway, this learns the AC、lightening impulse and switching impulse discharge performance of short rod-plane air gaps below 500 mm and short insulator strings in the air condition of altitude over 4000m simulated in the cylindrical artificial climate chamber. And based on the result of test, the dissertation analyzes the discharge performance of short rod-plane air gaps and short insulator strings in the air condition of altitude 4000m and over, and put forward the correction formula of short rod-plane air gaps and short insulator strings in the air condition of altitude over 4000m. The study works and conclusion of the dissertation is followed as:The discharge voltage of short rod-plane air gaps and short insulator strings will also decrease with the altitude increasing or atmospheric pressure decreasing, but the decreasing trend is relative to the scale of altitude, the decreasing speed of discharge voltage is slower in the high altitude region. The change of atmospheric pressure reflect the change of the altitude and the change of the temperature、humidity and relative air density in the different altitude region, So the atmospheric pressure is able to be use for the characteristic parameter of token the effect of the altitude on external<WP=6>insulation voltage; the discharge voltage of short air gaps and short insulator strings is the power function of atmospheric pressure ratio, as equation U=U0(P/P0)n, the factor index n is relative to the voltage type and gap forms or insulator structures. The dissertation also analyzes the discharge basic principle of short air gaps and short insulator strings in the high altitude regions. The study result of the dissertation provide the test data and theory reference for power supply systems of on-going Qinghai-Tibet railway and the design of other external insulation in the region 4000 m and above,更多还原