SHEMAR’s Substation Composite Insulators Made Great contribution for Middle Tibet Power Grid Coonection Project （Nyingchi to Qamdo）Release Time：2017-06-07 Publisher：Eric Zhu
After the construction of Geermu in Qinghai to Lhasa in Tibet 750/±400kV AC/DC power grid connection project and Batang in Sichuan to Changdu in Tibet AC power grid connection project, SHEMAR substation composite insulators are applied again in the middle Tibet power grid connection project.
It is reported that the Northwest China has the environmental characteristics of high attitude, high UV intensity, strong sandstorm and atrocious weather, which poses a big challenge for SHEMAR substation composite insulators. However, SHEMAR innovative silicone rubber coat can meet the demands of 40 years’ service life under the most severe environment.
Actually, the first SHEMAR substation composite insulators being used in the Northwest China can trace back to 1999, which has being used in Toksun country in Xinjiang for about 18 years. And now it is still in a good condition under such an area with high UV intensity and strong sandstorm. No defects happened in these 18 years without any maintenance, including cleaning, sweeping and PRTV painting. And SHEMAR chose some samples from these composite hollow insulators to have the test, and the results showed that these composite hollow insulators still kept good electrical performance, sealing performance and mechanical performance, especially the silicone rubber coat because the elongation at break still kept around 260% almost same as the data tested in 1999.
In 2007, three SHEMAR composite hollow insulators were applied in GIS equipment in 750kV Guanting substation with the attitude of 2500 meters, which was located in Tibetan Plateau reported as one of the most harsh environment area. In the following 6 years, the 750kV switchgear equipment bushing in Shaanxi, Gansu, Qinghai, Ningxia, Xinjiang all adopted composite bushing, and SHEMAR provided 99.9% composite hollow insulators for these bushings.
In 2010, the State Grid conducted the Geermu in Qinghai to Lhasa in Tibet 750/±400kV AC/DC power grid connection project, and quantities of SHEMAR substation composite insulators were applied in substation converter station of this project. Meanwhile, in DC transmission line, SHEAMR line composite insulators had better performance compared with other suppliers for the good performance of SHEMAR silicon rubber materials.
Since 2013, the Northwest China had started the construction of all-composite insulator substation, which was treated as a milestone event in the revolution of substation insulation materials. In the construction of AIS substation and GIS substation, all equipment with all voltage level adopted substation composite insulators. The reason why the power grid used composite insulators was that with lower purchasing price and operation cost composite insulator had better performance compared with porcelain insulator in the aspects of preventing pollution flashover, explosion and fracture accident.
In 2014, Batang in Sichuan to Changdu in TibetAC power grid connection project started, and there were 4 AC substations needed to be built, including two 500kV substations and two 220kV substations. The State Grid also built four composite insulator substations to transmit power to Tibet.
In 2017, the construction of middle Tibet power grid connection Project will connect the Qinghai-Tibet power grid project and Sichuan-Tibet power grid project, which is expected to ease power shortages and improve living standards in Tibet. Based on the previous good performance under the severe environment in the Northwest China, SHEMAR is the main supplier for the construction of the five composite insulator substations. In its total life cycle, SHEMAR composite insulators will make great contribution for middle Tibet power grid connection without any maintenance.