ABSTRACT
Present-day power system is invariably supplied by a number of power plants. There is a growing complexity as the more flexible generation technologies like renewable sources are feeding into the system. To achieve good quality of service with minimum cost per unit of energy supplied, it is necessary to have a judicial mix of different sources. The purpose of economic operation of power system is to reduce the operating cost of generation to the minimum. The system control engineer has to consider a number of factors while interchanging energy from one power station to another station. Hydrothermal scheduling plays an important role in the operation planning of power system satisfying constraints related to the two systems. Power systems must always have some amount of operating reserve that can instantly respond to a sudden increase in the electric load or a sudden decrease in the renewable power output. Operating reserve provides a safety margin that helps ensure reliable electricity supply despite variability in the electric load and the renewable power supply. This chapter deals with these aspects including power system reliability. System Average Interruption Frequency Index (SAIFI), System Average Interruption Duration Index (SAIDI) and Customer Average Interruption Duration Index (CAIDI) including Loss of Load Probability (LOLP), Loss of Load Expectation (LOLE), Expected Frequency of Load Curtailment and Expected Duration of Load Curtailment are all narrated in this chapter. Further contingency analysis is also narrated in this chapter.
