The trend of the electric power consumption shows growth in Hungary. The capacities of the transmission and distribution system and power plants must follow the growing demands in order to provide safe and uninterruptible service. The MAVIR Ltd. as the owner and operator of the Hungarian transmission system is obligated to make the necessary improvements . The development of the 400 kV voltage level system elements are required in order to reduce the loss and ensure the sufficient transmission capacity.
Five new substations and about 1200 km of transmission lines have been put in operation since 2004. Such a huge development can be performed efficiently with the standardization of the most important sections (planning, licensing, construction) of network. Developing similar plans for the similar requirements along with reducing the costs can lead to a transparent transmission system design. The standardized substations are outdoor designed, air insulated with tube busbar, one and a half circuit breaker configuration switchgear (at 400 kV level) and double busbar configuration switchgear (at 120 kV level), installed with two 250 MVA 400/120 kV level transformer and two 70–72 Mvar 18 kV level tercier shunt reactor.
Because of several issues, it is not possible to standardize all parts of the substations. Experience has shown that the best solution is the standardization only the functional parts of the substation and not the whole. It is necessary to find the optimal rate of standardization for the long-therm economical establishment by comparing its cost with the induced savings. It is suggested to prepare the standardized plans for connections to elements that are not part of the system yet, but in the near future it will be necessary to integrate them.