Porcelain and glass string insulators have been widely used in suspension applications on UHV DC projects in China due to their mechanical and electrical properties and also the depth of local operating experience.

In the past, the main options for support insulators at air-insulated HVAC substations were either solid core porcelain or composite insulators up to 245 kV. In addition, RTV coatings have at times been applied to solid core porcelain post insulators to improve their pollution performance.

South Bohemia abounds with wonders, including medieval towns with cobblestone streets and fairy tale castles. But what is truly unique in this pastoral region of the Czech Republic has nothing to do with baroque villages.

It has long been known that corona can lead to insulation failure. However not all aspects of the problem are fully understood and are still being researched, including magnitude and duration of corona to initiate degradation, best detection methods and development of suitable tests to predict performance in its presence.

Because of increasing difficulties in securing approvals for new transmission corridors, various new technologies for line uprating have been developed and are now being implemented. The basic idea is to use existing line corridors to transfer more power.

Powerlink Queensland is an Australian government owned network service provider whose extensive transmission network operates at 110 kV, 132 kV, 275 kV and 330 kV.