Source: PJM Interconnection
The Smart Grid is taking a big step forward with a program to extend the digital intelligence of North America's largest electric transmission system, the PJM Interconnection. With the aid of a U.S. Department of Energy stimulus grant, PJM and 12 member transmission owners are installing more than 80 additional high-tech monitoring units called phasor measurement units or synchrophasors.
The results will improve operators' visibility of the grid and strengthen reliability.
"It's like moving from an old black-and-white TV to a wide screen HD TV," said Terry Boston, PJM president and CEO. "A more detailed, clearer picture of the system at any given moment allows us to more easily detect over a wide area and avoid problems on the transmission system so that we can move the maximum amount of market transactions safely."
Synchrophasors provide more precise data at a much faster rate. Voltage and current at a given location can be measured more than 30 times per second. Traditional technology takes measurements every four seconds. Data are 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.
Under the new program, 12 PJM transmission owners will install phasor measurement units in substations in 10 different states (Delaware, Illinois, Indiana, Maryland, Michigan, New Jersey, Ohio, Pennsylvania, Virginia and West Virginia). The PJM system has just under 20 phasor measurement units in place already.
The $27.8 million program will be completed over a three-year period. Each of the 12 transmission-owner companies will receive a portion of the $14 million Department of Energy matching funds grant to install and configure the phasor measurement units at their sites. The department and PJM recently executed the final agreement for the grant.
The transmission owners who are part of this project are: Allegheny Power, American Electric Power, Baltimore Gas & Electric Company, Commonwealth Edison, Dominion Virginia Power, Duquesne Light Company, FirstEnergy Corp., PECO, Pepco Holdings, Inc., PPL Electric Utilities, Public Service Electric & Gas, and Rockland Electric. Collaborating on the project are Virginia Tech, Quanta Technology and the Electric Power Group.
PJM Interconnection, founded in 1927, ensures the reliability of the high-voltage electric power system serving 51 million people in all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and the District of Columbia. PJM coordinates and directs the operation of the region's transmission grid, which includes 6,038 substations and 56,500 miles of transmission lines; administers a competitive wholesale electricity market; and plans regional transmission expansion improvements to maintain grid reliability and relieve congestion.