Two series capacitors each rated at 372 Mvar supplied by Hitachi Energy are in operation in the North China Power Group´s 500 kV power transmission network west of Beijing. The purpose of the installation is to enhance the power transmission capability and availability of this 500 kV grid, essential for safe energy supply to the country´s capital.
The series capacitors came on line in 2001, after a record breaking project time, less than nine months from awarding of the contract.
North China Power Group (NCPG) runs and operates North China Power Network (NCPN). It supplies an area of close to 1,5 million square kilometres and a population of about 140 million people with electric energy, including the Beijing municipality. By the end of 1997, the installed capacity of NCPG amounted to nearly 28.000 MW, with an annual production of over 140 TWh.
Particularly the capital area is undergoing rapid development, and electric power demand is growing at a steady pace. This also puts demands on development at an equal pace of the power grid on which the capital is relying for its energy supply. In this context, series compensation is an attractive as well as a very efficient means for grid reinforcement. That means, series capacitors are constructed and put into operation in the transmission corridor already existing. From a project implementation point of view, this is not only faster, but also less expensive than building new lines. Plus, of course, much less of an impact on the environment.
|Rated system voltage:||500 kV|
|Rated current per phase||2100 A|
|Rated phase reactance:||28.4 Ω|
|Degree of compensation:||35%|
|Rated reactive power:||372 Mvar|
|Rated ZnO varistor energy:||90 MJ/3-phase|