Coordinated Design of PSSs and WADC to Tolerate Communication Failures

Abstract

In power systems, damping controllers are widely used to improve the damping ratios of oscillation modes of systems and avoid loss of angular stability. Wide-Area Damping Controllers (WADCs) are controllers that use remote data from Phasor Measurement Systems (PMUs) to mitigate low frequency oscillation modes of power systems with low damping ratios and are mainly effective in inter-area modes. Power System Stabilizers (PSSs) are effective in improving the damping rates of local modes but have limited effects in inter-area modes. PSSs and WADCs are damping controllers that present distinct benefits and design challenges. A concern in the operation of the WADC is the susceptibility of communication channels to failures or cyberattacks that could affect the proper operation of the WADC in the power system. This work proposes a PSS and WADC coordinating design method to improve the damping rates of the oscillation modes of the system and be tolerant to permanent communication failures at the same time. The coordinated design method was evaluated in the IEEE 68 bus system by modal analysis techniques and dynamic simulations. The obtained results showed that the system with both types of damping controllers provided well-damped angular responses and there are guarantees of good dynamic performance even with communication failures and contingencies. Furthermore, the proposed method can be solved by different techniques and the application of the Gray Wolf Optimizer showed good results.