A methodology of secure and optimal operation of a power system for dynamic contingencies

Just as in static security constrained optimization of power systems, there is need to do preventive scheduling if the system state is found to be insecure through dynamic contingency analysis. Current work in this area based on energy functions and sensitivity considerations only computes another feasible and normal operating point either through the controlling u.e.p or the potential energy boundary surface method. In this paper we use the hybrid method which involves integration of the system equations only once till the controlling u.e.p is reached to compute the energy margin. Based on the sensitivity of the energy margin to generation powers, rescheduling is done through an OPF algorithm resulting in a secure but optimal solution. Results on a 3 machine, 9 bus system are very encouraging. This methodology could form a basis for integrating current OPF packages into the DSA package.