Phasor Measurement Unit

Definition
Popularly referred to as the power system’s “health meter,” Phasor Measurement Units (PMU) sample voltage and current many times a second at a given location, providing an “MRI” of the power system compared to the “X-Ray” quality available from earlier Supervisory Control and Data Acquisition (SCADA) technology.

Overview
Offering wide-area situational awareness, phasors work to ease congestion and bottlenecks and mitigate &mdash; or even prevent &mdash; blackouts.

Typically, measurements are taken once every 2 or 4 seconds offering a steady state view into the power system behavior. Equipped with Smart Grid communications technologies, measurements taken are precisely time-synchronized and taken many times a second (i.e., 30 samples/second) offering dynamic visibility into the power system.

Adoption of the Smart Grid will enhance every facet of the electric delivery system, including generation, transmission, distribution and consumption. It will energize those utility initiatives that encourage consumers to modify patterns of electricity usage, including the timing and level of electricity demand. It will increase the possibilities of distributed generation, bringing generation closer to those it serves (think: solar panels on your roof rather than some distant power station). The shorter the distance from generation to consumption, the more efficient, economical and “green” it may be. It will empower consumers to become active participants in their energy choices to a degree never before possible. And it will offer a two-way visibility and control of energy usage.