New Math Tools Developed to Monitor Power Grid

(Brookhaven National Lab)

University and company engineers have developed new mathematical tools for monitoring and measuring electrical power grid performance. The team that developed the tools — from North Carolina State University in Raleigh, Rensselaer Polytechnic Institute in Troy, New York, and Southern California Edison in Los Angeles — published their results in the online issue of IEEE Transactions on Smart Grid (paid subscription required).

The team, led by NC State engineering professor Aranya Chakrabortty, adapted synchrophasors, which are real time, high-resolution power-system measurements of voltages and currents. They provide a detailed view of complex events taking place in a power system. Synchrophasors are recorded by sophisticated digital devices called phasor measurement units (PMUs).

It’s the PMUs, says Chakrabortty, that give synchrophasors the ability to measure and model the complex behavior of a large, geographically distributed power system, such as the North American power grid, especially taking into account the  system’s interconnected nature.

He explains that understanding the propagation behavior of major disturbances across the North American power system calls for highly reliable and rigorous mathematical models that capture the dynamics of its various clusters, as well as the way those dynamics will evolve when the clusters are connected to each other in the overall system. “We need to have a better understanding of how a disturbance entering one generation cluster, or localized group of nodes,” adds Chakrabortty, “may spread across the entire system, creating havoc in its neighboring clusters.”

Chakrabortty notes, “Traditional measurement methods in power systems are too slow and, therefore, incapable of capturing these dynamics, which can change dramatically in fractions of a second. With the synchrophasor technology today, such models are possible.”

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