RELIABILITY AND COST ANALYSIS OF INTERCONNECTED POWER SYSTEMS WITH JOINTLY OWNED GENERATING UNITS OPERATING IN A MARKET ENVIRONMENT

摘要

The application of the competitive electrical energy market in many countries worldwide has increased the use of interconnections among different areas due to the high interest of market parties for economical and efficient cross-border power exchanges [1, 2]. The interconnections among utilities also improve operating reliability and flexibility and reduce the installed generation reserves. Usually, utilities construct new power plants for meeting the increasing load demand or for replacing old plants, which need large investments. However, interconnected utilities may jointly install a generating unit in which the utilities may have different or similar shares or one of the interconnected utilities may buy a certain percentage of the output of a generating unit, which already exists in the other utility. This means that the failure of a jointly owned generating unit will cause a decrease in the available capacities of all the sharing utilities simultaneously. Because of this correlation, the conventional reliability model of a generating unit cannot be used to represent jointly owned generating units. One of the most important areas that needs an increased attention is the reliability assessment of the transmission networks of all interconnected utilities by taking into account both their generation and transmission facilities. The impact of interconnections and the jointly owned generating units can be quite significant on both the load-point and the system reliability performance. The reliability evaluation techniques at Hierarchical Level Two (HLII) [3] can be utilized to assess the impact of jointly owned generating units on the interconnected systems adequacy. Such studies have been published using analytical techniques [4, 5].