A Robust Communication-Based Special Protection System

This article investigates the application of an exponential weighted moving average (EWMA) scheme to a previously introduced communication-based special protection system (SPS). The EWMA adds buffering to increase the robustness of the SPS in the presence of network congestion and other forms of communication disruption. The EWMA-enhanced SPS compensates for the network layer's lack of a communication guarantee to provide for increased stability and integrity under transient instabilities. The performance of the proposed SPS is evaluated using the electric power and communication synchronizing simulator (EPOCHS) simulation platform, which combines the PSS/E electromechanical transient power system simulator with the NS2 network simulator. The SPS is evaluated in terms of its ability to properly calculate a disturbance size and to react to the disturbance before the system reaches the minimum frequency threshold of 58.8 Hz and before 0.5 seconds have passed. Experimental results indicate that the proposed SPS with EWMA can help ensure power grid stability in the face of heavy competing network communication traffic.