GridSweep
This project is developing a new class of measuring instrument called the GridSweep probe to reveal subtle dynamics that can threaten electric grid stability. Although widely recognized, these dynamics have never before been directly observable. This type of probe should advance bulk grid reliability, security, resilience, and the capability to operate grids securely with high contributions from inverter-based generation.
Background
The electric grid has incipient instabilities that are known or suspected, but not easily measured. These include reduced system inertia, vulnerability to forced oscillations, and adverse interactions from inverter controls. Grids are also vulnerable to time-synchronized dispersed load changes, whether intentional or unintentional. This project will develop a new type of probe to provide visibility of grid frequency response behavior, with the goal of mitigating the risk of blackouts and supporting intelligent decision making for critical infrastructure.
Objectives
- Create a completely new class of active grid instrumentation for situational awareness of bulk grid and connected resources.
- Apply data techniques from seismology for ambient noise analysis and small-signal extraction.
- Characterize bulk grid inertia, generator control loop parameters, frequency-specific grid response and location-specific load dynamics live in situ.
- Demonstrate a synchronized GridSweeper network with geographic correlation.
Project Description
This project builds on prior work funded by DARPA, the Grid Thumper, which injected a precisely timed 1-MW impulse and observed it, tens of miles away, using high-precision microPMUs with a measurement resolution of 10 PPM. The graphic illustrates the observation in San Rafael, CA, of a regular "thump" injected in Alameda, CA. GridSweep probes will be much smaller and portable than the GridThumper, made possible by new techniques for injecting a recognizable signal, along with new hardware and algorithms for measuring that signal miles away at 100 PPM resolution. One approach for making such a tiny signal observable will be an ambient noise correlation algorithm borrowed from seismology. After testing the prototype and algorithms in the lab setting, the project will deploy GridSweep probes and characterize the frequency-specific response of the grid in different geographies. In the future, this will inform strategies to protect power systems from certain types of threats, and to design inverter control systems that help stabilize the grid.
Funding
This project is funded by the 2019 Grid Modernization Lab Call, Topic Area 3: Advanced Sensors and Data Analytics, Subtopic 3.4.2: Monitoring for Critical Infrastructure Interdependencies.
Team Members
Principal Investigator: Alexandra von Meier, Berkeley Lab
Co-PI: Philip Top, LLNL
Senior Personnel: Dan Arnold (Berkeley Lab), Kristina Hamachi LaCommare (Berkeley Lab), Alex McEachern (Lead at McEachern Laboratories), Eric Matzel (LLNL)
Partners
Lawrence Livermore National Laboratory
McEachern Laboratories
Idaho Power
Hawaiian Electric Co.
Links
gridsweep.com