特高压半波长输电系统绝缘配合研究

Insulation Coordination of UHV Half-wavelength Power Transmission System

特高压半波长输电技术具有输送距离长而不需要建设中间开关站等优点,但沿线路的运行电压、工频过电压和操作过电压特征以及过电压限制措施与传统的特高压输电技术有明显不同之处,因此需要对半波长输电线路的沿线稳态运行电压、工频过电压、操作过电压、绝缘配合等进行研究。绝缘配合研究主要包括:确定变电站电气设备绝缘水平和空气间隙距离、确定线路绝缘子配置和空气间隙距离,为设备制造和工程设计提供参考。将特高压半波长线路的绝缘配合方案与晋东南—荆门—南阳1 000 kV特高压试验示范工程的绝缘设计进行比较。结果表明,特高压半波长输电工程设备和线路的绝缘配置基本上可以直接沿用特高压示范工程。

One of outstanding advantages of ultra-high voltage half-wavelength AC transmission （UHV HWACT） technique is that the intermediate switching station does not need to built under long transmission distance. However, its operation voltage along transmission line, power frequency overvoltage and characteristic of switching surge as well as the measures to suppress overvoltage are evidently different from those of traditional UHV power transmission, thus it is necessary to research steady state voltage along the line, power frequency overvoltage, switching surge and insulation coordination of UHV HWACT. The researches on its insulation coordination include following items： to determine insulation level of power equipments in substations and the distances of air gaps, to determine insulation configuration for transmission line and related distances of air gaps to offer reference for equipment manufacture and engineering design. Comparing the insulation coordination scheme for UHV HWACT with the insulation design for 1 000 kV AC power transmission pilot project from Southeast Shanxi via Jingmen to Nanyang, comparison results show that the equipments and insulation configuration for 1 000 kV AC power transmission pilot project can be directly applied to UHV HWACT.