with High-Precision GPS Time
For most of us, the
only time we think about the systems that supply our electrical power is when they fail
us. Street lights winking off, the VCR flashing 12:00, or flicking a switch with no result
are a few ways we're reminded that there's a fallible organization responsible for
providing our energy.
Given the amount of power a power company supplies, the number of customers they
service, and the high-precision timing that the generation and transmission of electricity
requires, it's surprising that power doesn't fail more often. Increasingly, GPS is
becoming the tool that is used to provide that timing.
Since 1988, the Bonneville Power Administration in the U. S. Pacific Northwest has been
integrating GPS technology into its operations. As an integral part of any electrical
operations system, timing is the technology on which many of its functions are based.
Generation and power transfers are planned in advance. Utilities coordinate with each
other by making adjustments on a GPS timed schedule. Outages for maintenance are scheduled
to ensure that they do not interrupt reliable power delivery. Disturbance records are
aligned with recorded GPS time tags for analysis and comparison with related information.
Price varies with demand, so even billing is based on time. Advanced applications like
locating power line faults (short circuits) and real-time phase measurement require
continuous timing with high precision. And bad timing can throw a monkey wrench into all
BPA administrator, Kenneth Martin puts it all in perspective. "With help from GPS
we are finding ways to develop a comprehensive system that meets the needs of new
applications while continuing to serve existing systems. In short, we have found that GPS
is the universal answer for power system timing, meeting all requirements of accuracy,
reliability, coverage, and cost."