FLEXIBLE CONTROLLED SYSTEM FOR DC CURRENT TRANSMISSION: PROSPECTS FOR APPLICATION IN RAO 'EES' ROSSII Co.

摘要

Problems of major concern for the United Energy System of Russia (RAO "EES Rossii" Co.) have been and continue to be: 1. Insufficient capability of the interconnection lines and network-forming lines, which puts limitations on the electric energy exchange under free market conditions. At present, there are problems with the parallel operation of the Regional United Energy System (RUES) Siberia and RUES European Region and the transmission of electrical energy from the Tyumen' Power System to the Ural Region; insufficient capabilities for power transmission between the RUES Center and the North Caucasian RUES North Caucasus and Trans-Caucasian RUES, lack of parallel operation for the RUES Siberia and the RUES East, etc. In the near future, cross-section limitations may emerge for the RUES Center, RUES Middle Volga, and RUES East-West. There are limitations on the power output from a number of hydropower plants (Pechorskaya HPP, Kol'skaya HPP, etc.). 2. Poor control exerted over power networks and the limited availability of facilities for voltage and reactive power control and, as a consequence, hazardous voltage levels in the network during the periods of diurnal and seasonal load drop. Not infrequently, in order to stabilize the voltage level, it becomes necessary to switch off the 370 - 750 kV interconnection lines, which is detrimental to the operation of the EES Rossii. 3. Inefficient power distribution over parallel lines of different voltage class and, as a consequence, the underuse of existing electrical networks, excessive line losses, and increased cost of electrical energy transmission. For example, such situations have occurred in 330/220/110 kV networks (RUES East-West) and 500/220/110 kV networks [RUES Center (Mosenergo)].