The distribution grid is quickly evolving into a real-time system that dynamically changes instantaneously. As connected loads continuously vary, component failures necessitate changes in the interconnected system of feeders and substations. These system changes typically happen extremely fast, such as when a failed piece of equipment is isolated by the protection systems. When these high-speed dynamic changes take place, a true smart grid control system must react in symphony with these changes to provide consumers with alternative power sources.

Conventional supervisory control and data acquisition (SCADA) systems are historically more static in nature and not necessarily able to keep up with the increased need for real-time reactions in the power grid. Measured field status information is slowly communicated up to an operations center, and the measured information could take minutes before it reaches the operator screens. Because of this delay, true real-time synchronous operations cannot be accomplished. Operators are forced to wait for stable system conditions or run possible simulated sequences before actual switching sequences can be executed to provide alternative power to consumers.

Advances in intelligent grid technologies promise to close this gap by providing faster-acting or real-time systems, and utilities already are making vast improvements to achieve success. One example of a utility making these advances is Wake Electric Cooperative.

Faster, Faster

To date, the board of Wake Electric has approved the deployment of advanced metering infrastructure (AMI), an outage management system (OMS) and, most recently, a real-time distribution feeder automation project. The cooperative is continuously looking to implement and test new technologies that could improve operations. These systems were once considered “nice to have,” but the investments are now mission critical for Wake Electric’s grid to become truly smart.

Established in 1940, Wake Electric is trusted to serve more than 37,000 members in parts of seven counties of North Carolina, U.S. It operates more than 3,100 miles (4,989 km) of transmission and distribution lines, and, for a cooperative, its density is relatively high with an estimated 12 meters per mile. To optimize its network infrastructure decisions, Wake Electric chose the services of the Siemens Smart Grid. Siemens first communications modeling and simulations using its Smart Grid Communications Assessment Tool (SG-CAT) to determine where Wake Electric would benefit most in terms of expanding its communications infrastructure.

Wake Electric Cooperative, WiMAX installation