1000kV特高压交流变电站铝管母线末端屏蔽方式研究  

Study on Terminal Shielding Way of Aluminum Tubular Bus in 1 000 kV UHV AC Substations

作　　者：李禾[1] 王闯[1] 刘鹏[1] 彭宗仁[1] 

机构地区：[1]电力设备电气绝缘国家重点实验室(西安交通大学),陕西省西安市710049

出　　处：《电网技术》2014年第9期2562-2569,共8页Power System Technology

摘　　要：管型母线因其良好的载流性能与可靠的机械连接特性被广泛应用于高压电站中,在特高压交流电站中,管形母线末端的屏蔽方式问题日渐突出,研究其屏蔽结构对特高压交流电站的设计具有重要意义。针对1 000 kV特高压交流长治站在带电试运行过程中硬铝管母线高压并联电抗器侧末端出现的电晕问题,使用有限元方法建立三维仿真模型,仿真计算了管母末端的电位和电场分布,找出了引起电晕放电的原因,并在此基础上研究了几种屏蔽方式的效果和可行性,提出了管母末端采用直径250 mm的半球形封盖板结构和于管母上方加装管径300 mm的均压环相结合这一合理的屏蔽方式。该屏蔽方式明显改善了管母末端的电场分布,使管母高压电抗器侧末端附近的场强最大值降低至1 390 V/mm,较原结构场强最大值降低了44.4%,满足局部控制场强的要求,有效抑制了管母末端的电晕放电。研究方法已经成功应用于特高压交流长治站中,并对类似结构电力设备的设计具有借鉴意义。As a result of its good current-carrying performance and reliable mechanical connection property the tubular bus is widely used in HV substations. In UHVAC substations the terminal shielding of the tubular bus becomes more and more serious, so the research on the shielding structure for tubular bus terminal is of significance to the design of UHVAC substations. In allusion to the corona appeared at the terminal of aluminium tubular bus connected to the top end of the HV shunt reactor during the trial operation of 1 000 kV UHVAC Changzhi substation, a tri-dimensional simulation model is built by finite element method and both distributions of potential and electric field at the terminal of the aluminium tubular bus are simulated and the reasons causing the corona discharge are found; on this basis the effects and feasibilities of several kinds of shielding ways are researched, and then a reasonable way, which is composed of two parts： one is a semi-spherical sealing cover plate with a diameter of 250mm connected to the tubular bus terminal and the another is a grading ring with diameter of 300mm added above the tubular bus, is proposed. Using the proposed shielding way, the distribution of electric fired at the tubular bus terminal is obviously improved and the maximum electric field intensity near the top end of HV shunt reactor connected to the tubular bus terminal is reduced to 1390V/mm, so this maximum electric field intensity is reduced by 44.4% than that of the original structure, thus the demand of locally controlling the field intensity is met and the corona discharge at the terminal of tubular bus is effectively suppressed. The proposed shielding way is successfully applied in UHVAC Changzhi substation.

关 键 词：特高压交流变电站 铝管母线 电晕 有限元 电场强度 屏蔽方式 

分 类 号：TM721[电气工程—电力系统及自动化]