1100 kV特高压交流变电站开关设备低温应对措施

随着特高压交流工程建设的不断开展,越来越多特高压变电站将建设在低温地区。由于特高压开关设备普遍采用SF_6气体绝缘,在低温地区使用会存在低温液化问题,降低设备运行稳定性,提升电网运行风险,需采取措施提高设备耐受低温能力。基于设备重要性的考虑,对于1 100 kV GIS,宜采用户内布置方式。对于户外使用的1 100 kV出线套管和分支母线可采用降低气压的方法降低气体液化温度。对于其他电压等级的GIS设备,可在设备外壳加装加热装置,按一定程序对设备气室加热,保证绝缘和灭弧介质SF_6的状态稳定。上述低温应对措施均通过了低温试验考核,试验结果将为后续低温特高压站的建设和运行提供指导。

Countermeasures on Low Temperature for Switchgear in 1 100 kV UHVAC Substation

As the UHVAC power project develops, more and more UHV submission will build at low temperature area. As the insulating medium of UHVAC switchgear, SF6 is likely to liquefy at low temperature, which may reduce the stability of the switchgear and increase the operation risk of the state grid. It is necessary to take measures to improve the cold-resistant ability of the switchgear. Based on the importance of different switchgear, it is appropriate to carry out indoor installation for 1100 kV GIS. To some outdoor 1 100 kV busing and bus, reduce the SF6 pressure can make the liquefaction temperature lower to accommodate the cold environment. To 126 kV GIS and 550 kV GIS, it is effective to add heating devices around the switchgear, and heat it at certain procedure, which can keep the SF6 stable. All the measures have been tested by low temperature test. And the result can provide guidance for the latter construction and operation of UHV submission.