Robustness study of dynamic inversion technique used in power system stability analysis

Modern power systems are operating increasingly closer to their control and operational limits. Such stressed conditions can lead a system to become unstable and hence it has become necessary to properly model the effect of such limits on the system. Also, gradual system parameter variations such as load increase, combined with contingencies, lead to system instabilities. The accuracy of power system stability analysis depends on the accuracy of the models used. Use of more accurate models would result in more reliable analysis, in terms of the power transfer capability. In this paper, a single Machine Infinite Bus (SMIB) system has been considered and it has been assumed that the inertia and damping coefficient of the machine is not measured properly and a random variation has been introduced to these parameters. In such a case, the robustness of the nonlinear control law, Dynamic Inversion (DI) has been studied. The control action is achieved using thyristor controlled series capacitor (TCSC).