MISO deploys synchrophasors to improve reliability


Richard Doying,
VP Operations,
Carmel, IN, U.S.A. — (METERING.COM) — October 1, 2012 – MISO, the regional grid operator for much of the U.S. Midwest, has deployed into production use of synchrophasors into two critical aspects of grid analytics – system modeling and after-the-fact event analysis.

With 161 synchrophasor measurement devices installed and now operating along the 50,000-mile interconnected system in the MISO 11-state region, MISO’s grid operators have a new, highly sensitive measurement for grid diagnostics using phasor measurement units (PMUs).

MISO has also implemented a dynamic model enhancement process using measurement results from these PMUs. This process will allow MISO to more accurately determine transfer limits on the system. Improving the precision of dynamic models will also result in more reliable and efficient operations by enabling safe operation of the bulk electric system closer to its maximum limits.

With synchrophasors, voltage and current at a given location can be measured more than 30 times per second, compared with current technology, which records measurements every two seconds. Synchrophasor data are also time-stamped with signals from global positioning system satellites, enabling measurements from different locations to be time-synchronized and combined to create a detailed, comprehensive view of the transmission system.
After-the-fact analysis includes the study of specific grid activity or disturbances to determine whether changes are needed to prevent larger threats to regional reliability. Using synchrophasor data to conduct event analysis helps MISO and its transmission owners more rapidly determine an accurate sequence of events and accurate picture of how equipment responded, resulting in more timely and accurate evaluations of disturbances.
“Synchrophasor data provides a powerful analytical tool to help us better understand system activities and observed abnormalities,” said Richard Doying, vice president of Operations. “Analyzing that data after-the-fact is crucial to better understanding the impact of events on the power system. At the same time, incorporating this new-found knowledge into our models means being able to test for conditions ahead of time and improving our operating guidelines to ensure long-term grid reliability.”

In 2009, MISO received a U.S. Department of Energy Smart Grid Investment Grant award of $17.3 million towards the project, which is well ahead of original predictions for installation.

MISO expects to make available synchrophasor data to its real time system operators in April 2013.