±1100kV直流输电工程换流变压器阀侧套管的设计

换流变压器阀侧套管作为换流变压器的关键组成部分,长期以来依靠进口,对其进行设计具有重要意义。为此,基于GB/T 22674—2008《直流系统用套管》及国家电网公司2011年5月份颁布的《±1 100千伏特高压直流输电工程设备研制技术规范-换流变压器册》技术规范,对准东-重庆±1 100kV特高压直流输电工程换流变压器阀侧套管结构型式、外绝缘、性能及关键技术进行了研究。结果表明:换流变压器阀侧套管结构比较复杂,采用充SF6式型式比较好;绝缘水平比换流变压器绕组绝缘水平要提高不等系数,其中雷电冲击耐受和操作冲击耐受提高1.05倍,直流耐受、极性反转和工频耐受试验水平提高1.15倍。根据研究结果给出了准东换流站换流变压器阀侧套管的技术参数,对±1 100kV特高压直流输电工程换流变压器阀侧套管的研制具有重要指导作用。

Bushings Design of Converter Transformer’s Valve Side of UHVDC Transmission Project

On the basis of IEC GB/T 22674—2008 standard "Bushings for d.c.application" and the technical specifications of "±1 100 kV UHVDC transmission project equipment development specification for converter transformer" issued by the State Grid Corporation in May 2011,we investigated the structure type,external insulation,performance and key technology of the bushings of converter transformer’s valve side of the Zhundong-Chongqing ±1 100 kV UHVDC transmission project.The results show that,due to the complex structure of bushings of converter transformer’s valve side,it is better to adopt filling SF6-type,due to strict insulation level of the bushings,it is necessary to increase specification ratios as follows: for the DC voltage withstand type tests,the ratio is 1.15;for the DC polarity reversal type test,the ratio is 1.15;for the AC voltage withstand type tests,the ratio is 1.15;for BIL tests,the ratio is 1.05;for SIL tests,the ratio is 1.05.Moreover,the technical parameters of the bushings of converter transformer’s valve side of Zhundong converter station are provided.