A hybrid model for quantifying different operating states of composite power systems

The two most popular approaches for power system reliability evaluation, namely contingency enumeration and Monte Carlo simulation, have been combined to form a hybrid model to analyze different system operating states to provide a quantitative assessment of system risk. Both annualized and annual indices obtained using a seven-step load model are presented for two test systems. Selection methods are used to detect problem creating contingencies. A linear programming model for generation rescheduling, minimization of the amount of load shed, and correction of the voltage problem and Q-load curtailment is utilized with the hybrid model. Variance reduction techniques were investigated in order to reduce the computation time and to improve the simulation results