Maximum loadability of an isolated system considering steady-state and dynamic constraints

An optimization model to calculate the maximum loadability of a system when subjected to a severe fault is proposed. The model simultaneously considers steady-state and dynamic constraints, with the dynamics of the generators explicitly included in the formulation. The armature current and the field current heating limits of the synchronous generators are also taken into account. The model is solved using a conventional solver based on the primal-dual interior point algorithm, and tested in a real system with three generators. The results show that the dynamic constraints can significantly affect the maximum loadability of the system. The effect on the solution of the maximum allowed rotor angle deviation is studied over a wide range of angle limits. Finally, the effect on the loadability of increasing the generation capability of certain plants is studied.