Statistical trend tests for resilience of power systems

Through applications of relevant trend tests in the context of resilience analysis, this study conducts an empirical evaluation on the resilience of the U.S. power grid based on the database of the Electric Disturbance Events. To assess trends in systems resilience, we look into three key components associated with each black-out and recovery of power systems, i.e., the time between disruptions, the performance loss of each disruption and the time needed for recovery. We present a combined measure that takes into account all the three components. A modified Lewis-Robinson test is then developed for trend detection in this combined measure. To support the trend analysis of this combined measure, we further perform trend test for the performance loss and the recovery time. It is found that, among various North American Electric Reliability Corporation (NERC) regions of the U.S. power grid, the resilience in the Northeast Power Coordinating Council (NPCC) region has become better. Empirical evidence from the government financial support is used to substantiate these statistical findings.