Sensitivity analysis of power system reliability indices under emission constraints

This paper utilizes the concept of the shadow prices to perform sensitivity analysis of composite system reliability under the constraints of CO₂, SO_x and NO_x emissions. From the dual solution of a linear programming problem, shadow prices of the components of a system can be calculated. Shadow prices are then used to evaluate the sensitivity of the reliability indices and to rank system components from risk prospectives. The emission limits are considered as additional constraints to the linear programming optimization problem. After performing the sensitivity analyses, the ranking is evaluated again for emission limit violation and the components are ranked again in accordance. In this analysis, power system networks are modeled by incorporating the DC load flow with the linear programming with the objective function of minimizing load curtailment. Generating units and transmission lines are considered to have two states, up and down states. Generation capacity limits, emission limits and transmission lines power carrying capability limits are used as constraints. State enumeration technique was utilized in searching for failure states with ignoring events that have low probabilities. This method was applied on the 230 kv section of the IEEE RTS-79.