Components reliability parameters by mid-term deficit of electric energy

Reliability plays important role in rational management of transmission network. It concerns both the current activity of energy enterprise and forecasting of development of network, which cooperates with different kind of power stations and different customers. The required level of reliability results from agreements with customers. Mid-term deficit of power and electric energy occur mainly in winter and summer period. Usually maximum demand takes a stand in winter period and lowest temperatures in year, however in summer request for power and energy is definitely lower but potential of base of power station falls simultaneously. In this period numerous planned disconnections of lines and transformers occur. In addition maximum temperatures as well as numerous storms also and hurricanes are observed. In remaining periods i.e. in autumn or spring the probability of power or energy deficit is small, although can occur because of emergency reasons. The reasons of mid-term deficits can be located in the sector of energetic or outside it. Collected data from period 2005-2008 show on the reality of threat for whole energy system and it smallest part. In the paper the reasons of deficits of energy are analyzed. The reliability parameters of basic network components: transmission lines, transformers and bus systems; which are given from sufficient statistics of disconnections; are presented. Received indices shows the level of reliability and gives information about future period of utilization of elements. The methods of liquidation and moderation of deficit - especially in regional network in the area of commune are presented.