Enhancing Trust in the Smart Grid by Applying a Modified Exponentially Weighted Averages Algorithm.

摘要

The main contribution of this thesis is the development and application of a modified Exponentially Weighted Moving Algorithm (EWMA) algorithm, and its ability to robustly function in the face varying numbers of bad (malicious or malfunctioning) Special Protection System (SPS) nodes. Simulation results support the use of the proposed modified EWMA reputation based trust module in SPSs within a smart grid environment. This modification results in the ability to easily maintain the system above the minimum acceptable frequency of 58.8 Hz at the 95% confidence interval, when challenged with test cases containing 5, 10 and 15 bad node test cases out of 31 total load nodes. These promising results are realized by incorporating the optimal modified EWMA strategy, as identified by Receiver Operating Characteristic (ROC) techniques, where an optimal strategy is revealed. The optimal strategy maximizes true positives while minimizing false positives. Implementation of a modified EWMA within a reputation based special protection system does not account for each scenario that an electrical power engineer may face in the field. Instead, this research demonstrates that such an algorithm provides a robust environment to test within, in the hope of successfully meeting challenges and/or opportunities of the future.