Misoperation Reduction and Fault Detection/Localization by Distributed Signal Analysis

The increasing presence of distributed energy resources on the grid means that fault current can be drawn from sources other than the substation. Such reduction in fault current supplied by the substation can cause the substation protective-relaying equipment to fail to trip, leaving dangerous faults energized. In response, the U.S. Departmentof Energy is fostering the development of new technologies and tools that will advance protective-relaying capabilities to meet such challenges. By implementing a network of small, electronic devices that operate on the service side of the distribution grid, particular characteristics will be derived and securely-communicated to the substation. At the substation, digital signal processing and artificial intelligence will be used to operate on the information detect and localize faults, identify the protective-relaying equipment to be informed, and inform it, reducing misoperation. In Phase I, design, simulation, implementation, and testing will be conducted to build essential, math-based software. The software elements will enable: 1) extraction of the targeted, grid characteristics; 2) accurate identification of which protective-relaying equipment the information should be used to inform; 3) authentication by an on-grid message that uses a new method to prevent eavesdropping and tampering. A variety of simulations and on-grid tests will be used to verify the performance objectives set for each software element are met and demonstrating the effectiveness of the approaches. The capabilities provided by the system will enable a new generation of advanced, protective-relaying equipment. The technology can also be gracefully retrofitted into existing systems, without the need to interrupt the delivery of energy. Prompt awareness of faults and damage to the power grid are essential to rapidly protecting the public safety, minimizing revenue losses to utilities, and minimizing costs to rate-payers. The information provided by the system can also be used to make operational adjustments to the grid and optimize deployment of repair resources. Other benefits, such as grid-stabilization, can be provided through this technology, by application to the management of distributed energy resources.