Imagine a World Without E-mail or The World Wide Web — widespread, standardized, fast, robust systems that are ubiquitous in today's modern world. How would you communicate with friends, family and coworkers? How would you keep tabs on what's going on in your world?

Compare the broad level of connectivity that the Internet provides today with the environment of many electric system operators: little visibility outside of their control system; old-style supervisory control and data acquisition, and energy management systems; little advanced warning of pending trouble; little or no contingency analysis.

Imagine what Internet-style connectivity could do for today's electric system and its operators? How much more efficient could the grid be? How many outages might be averted? Given massive visibility, connectivity and information sharing, how much better could system operations be?

Central to this vision is synchrophasor technology that provides electric system operators and planners with a unique view of their electric system. Synchrophasors are literally “synchronized phasors” — a precision time-stamped representation of the magnitude and angle of key voltage and current parameters on the electric system. Given these measurements, we can improve power-system reliability and efficiency through wide-area measurement, monitoring and control.

The mission of the North American Synchrophasor Initiative (NASPI) — a joint venture with the U.S. Department of Energy (DOE) and the National Electric Reliability Corp. (NERC) — is to create a “robust, widely available and secure synchronized data (synchrophasor) measurement infrastructure for the interconnected North American electric power system with associated analysis and monitoring tools for better planning and operation, and improved reliability.”

NASPI is organized into several task teams, each focused on a particular aspect of the overall initiative. The scope of the data and network management task team includes the development of the hardware and software requirements to collect and disseminate the phasor measurement unit (PMU) data. The group is also responsible for defining the communications requirements between equipment, storage arrays, users and administrators.

The NASPI data measurement infrastructure currently involves a number of devices, including PMUs and phasor data concentrators (PDCs). PMUs are the source of synchronized phasor data. They are located in the field at the utility substation, receiving station or generating station. Phasor measurement data is typically transmitted continually from the PMU to a PDC. However, today's PDCs were not designed to support the scalability and flexibility required by NASPI's vision.

NASPI is working with the DOE to fund an effort to develop a data network specification that will provide the industrial-grade, de-centralized, expandable and standardized approach for the synchrophasor infrastructure. This will be accomplished through the introduction of a new component, the phasor gateway, and the synchrophasor data traffic will be carried on the NASPInet Data Bus.

Utilities interested in using this system will need to install a phasor gateway. This will be a utility's portal through which synchrophasor data will be published for use by others and subscribed to by interested parties. A phasor gateway may handle data directly from a PMU, but most likely will send and receive data from one or more PDCs.

The NASPInet data bus will transport data from one phasor gateway to another. The data bus is a single logical entity, but it will be comprised several components throughout, much like the Internet uses network routers and switches deployed everywhere the Internet is accessible. Participation in NASPInet will provide users to access to the entire resources of the network. This will allow utilities to easily monitor points of interest in neighboring areas and also regional entities will be able to easily monitor the their entire area of interest.

To support varying end-user application requirements with different data needs, five classes of synchrophasor data service have been identified with examples of each.

• Class A: Feedback control (small signal stability)

• Class B: Feed-forward control (state estimator enhancement)

• Class C: Visualization (operator visibility)

• Class D: Post Event (post-mortem event analysis)

• Class E: Research (Typical use: testing or R&D)

Well, it should be apparent by now that the future for high-speed movement of synchrophasor data is looking bright, thanks to the hard work and dedication of the many volunteers that make up the North American Synchrophasor Initiative and the continued support of NERC and the DOE.

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Paul Myrda (pmyrda@epri.com) is currently a technical executive at the Electric Power Research Institute, responsible for transmission smart grid, protection, synchrophasors and asset management.