A sensitivity based simplified model for security constrained optimal power flow

With the grid scale expansion and the network structure becoming more complex, how to keep the large power system reliable and secure is a great challenge. The security constrained optimal power flow (SCOPF) model is an effective way to consider economy and security coordinately. But due to the characteristic of SCOPF model itself, the model is very hard to solve when consider the security under a large number of contingencies. This paper proposes a simplified model based on partly linearized sensitivity to solve the SCOPF problem. The sensitivities between the variables under pre-contingency configuration and post-contingency configurations are used to establish the mew model. Some numerical results of IEEE 9-bus system show that the optimal solutions obtained from the new model can meet the demand in terms of economy and security, and solving with the new model is much faster than the traditional SCOPF model.