We study auxiliary signal-based fault detection in static linear systems with quadratic constraints. Auxiliary signals are perturbations that make faults easier to detect, at the cost of some disruption to normal operation. In this paper, we find minimally disruptive auxiliary signals that guarantee detection under set-based uncertainty. Our motivation is distance protection in inverter-dominated power systems, wherein small fault currents can go undetected by traditional schemes. We focus on static systems because distance protection is based on phasors. We formulate a general auxiliary signal design problem with constraints imposed by system operational requirements, and additive and multiplicative noise. We use a relaxation and duality to reformulate the problem as a semidefinite bilinear program. In the special case of additive uncertainty and no constraints, we obtain an analytical lower bound on the magnitude an auxiliary signal must have to guarantee detection. We solve the optimizations in an example based on distance protection, in which the auxiliary signal is negative sequence current. |
Josh Taylor received the B.S. from Carnegie Mellon University in 2006 and the Ph.D. from the Massachusetts Institute of Technology in 2011, all in Mechanical Engineering. From 2011 to 2012, he was a postdoctoral researcher at the University of California, Berkeley. He was an assistant and then associate professor at the University of Toronto from 2013 to 2023. He is currently an associate professor of Electrical and Computer Engineering at the New Jersey Institute of Technology. His research focuses on control and optimization of energy and water infrastructure. |
