中文摘要：

根据特高压输电系统对深度降低操作过电压水平的迫切需求及操作过电压常规限制方法在经济性和运行可靠性方面存在的不足,提出了操作过电压柔性限制方法的概念,阐述了可控金属氧化物避雷器（简可控避雷器）的原理。以我国目前正在建设的晋东南—南阳—荆门特高压交流试验示范工程为例,仿真计算了采用可控避雷器降低操作过电压的效果,结果表明,断路器无合闸电阻时,仅用可控避雷器可将系统相对地最大操作过电压倍数限制至1.6p.u.。对特高压输电系统操作过电压柔性限制方法的研究具有理论和工程应用价值,需要开展深入细致的研究。

英文摘要：

A concept of flexible measures is put forward to depress the switching overvoltage, on the basis of insistent demands of the UHV transmission system to lower switching overvoltage deeply and shortcomings of the existing measures on both economics and operation reliabilities. Working mechanism of the controllable zinc oxide arrester （the controllable arrester, shortly） is mainly discussed, Effect of the controllable arrester on depress the switching overvoltage can be demonstrated by the pilot UHV AC experimental project built in China, The results indicate that the controllable arrester is very useful. It can lower the maximum phase-to-ground switching overvoltage to 1.6 p. u. , even with those circuit breakers without closing resistors. The study on the flexible measures to depress the switching overvoltage has both academic and enfineering values in the UHV transmission system.