摘要
±1100 kV/12 GW特高压换流阀为目前世界上电压等级最高、输送容量最大的换流阀产品,为了确保外绝缘设计的可靠性,对±1100 kV/12 GW特高压换流阀屏蔽结构开展全新设计,并对换流阀外绝缘放电特性进行全面研究。首先引入有限元分析方法,将电场的场域问题转换成边界值问题,离散化后进行插值得到分布解,然后迭代出最优屏蔽结构。其次建立阀塔仿真模型进行电场仿真研究,结果表明采用的屏蔽结构使电场强度由原来的1.89 kV/mm减小到1.64 kV/mm,场强减小13.2%,电场分布效果更好。同时,对该屏蔽结构也开展了操作冲击U_(50)试验,验证了换流阀外绝缘电气强度。试验结果表明12 GW换流阀屏蔽罩结构设计合理,阀塔对墙的最小空气净距为6 m,满足该距离即可达到要求的绝缘水平,实际阀厅的空气净距有较大的安全裕度。
±1100 kV/12 GW UHV converter valve is a product which possesses the world′s currently highest voltage level and largest transmission capacity.In order to ensure the reliability of external insulation design,the present work conducted a thorough redesign of the shielding structure of±1100 kV/12 GW UHV converter valve,and a comprehensive study on the discharge characteristics of external insulation of converter valve.Firstly,the finite element analysis method was employed to transform the field problem of the electric field into a boundary value problem.After discretization,the distribution solution was obtained by interpolation,and then the shielding structure was iteratively optimized.Secondly,the valve tower simulation model was established for electric field simulation research.The simulation results showed that the electric field intensity of the shielding structure used in this paper is reduced from 1.89 kV/mm to 1.64 kV/mm(reduced by 13.2%),and the electric field distribution effect is better.Moreover,the shielding structure also passed the U_(50) test to verify the electrical strength of the external insulation of the converter valve.The test results showed that,with respect to the proposed shielding cover of 12 GW converter valve,the structural design is reasonable,the minimum air clearance between valve tower and wall is 6 m,above which the required insulation level can be readily satisfied.Therefore,for practical valve halls,a large safety margin of air clearance can be ensured.
作者
马元社
雒偲立
姚舒
MA Yuanshe;LUO Sili;YAO Shu(Xi′an XD Power Systems Co.,Ltd.,Xi′an 710065,China)
出处
《电工技术》
2023年第15期206-210,共5页
Electric Engineering
