Smart Grid

October 01, 2012

MISO Deploys Synchrophasor Monitoring Devices onto Electric Grid

MISO, a regional grid operator for much of the U.S. Midwest, said it reached some important milestones in smart grid technology recently. The company has deployed into production synchrophasors, or high-tech monitoring devices, into two critical aspects of grid analytics – system modeling and after-the fact event analysis. 

MISO (Midwest Independent Transmission System Operator, Inc.)  is an independent system operator (ISO) and the regional transmission organization (RTO) that provides open-access transmission service and monitors the high voltage transmission system throughout the Midwest and Manitoba, Canada. 

The company operates one of the world’s largest real-time energy markets and has 93,600 miles of transmission lines under its direction.

A phasor measurement unit (PMU) or synchrophasor is a device used to measure the electrical waves on an electricity grid, using a common time source for synchronization. This time synchronization allows synchronized real-time measurements of the grid. These synchrophasors are considered one of the most important measuring devices in the future of power systems.

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 devices known as Phasor Measurement Units or PMUs, said the company.

This will allow for  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.

"Today's incorporation of synchrophasor technologies into our grid analytics is the equivalent of introducing a new modern-day app to provide us with a more precise picture of system conditions on the grid, resulting in increased reliability and more efficient operations," said Richard Doying, Vice President of Operations for MISO, in a statement.

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.

"Synchrophasor data provides a powerful analytical tool to help us better understand system activities and observed abnormalities. Analyzing that data after-the-fact is crucial to better understanding the impact of events on the power system. This enables predicting when and why these situations take place so we can prevent them in the future.   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," said Doying.

The company said the data from the synchrophasor technology should be available by April of next year. 

Edited by Stefania Viscusi