Smart Grid

MISO uses smart grid technology to improve reliability

Carmel, Ind., September 27, 2012 — MISO and its transmission owners reached two milestones in implementing the U.S. Department of Energy’s goal of revitalizing the nation’s electric grid through smart grid technology.

MISO, the regional grid operator for much of the Midwest, deployed into production today use of synchrophasors, or high-tech monitoring devices, 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 devices known as phasor measurement units or PMUs.

MISO 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.

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.

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.

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

In 2009, MISO was among 100 recipients of the DOE‘s Smart Grid Investment Grant awards. MISO received a $17.3 million grant to fund the development and deployment of PMUs as part of the DOE’s effort to modernize the power grid and is well ahead of original predictions for installation. MISO members received a one-year extension to install additional synchrophasors at no extra cost, further improving grid reliability and predictability.