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The end goal of the FNET project is to develop a low cost, quickly deployable
synchronized PMU platform, the FDR. The deployed FDRs are time synchronized and
have high dynamic accuracy. Also, the installation costs for these units have been kept to
virtually zero. To this end, GPS is used for time synchronization, standard 120 V voltage
levels, such as those found in a typical office or home, are used for the power signal, and
proprietary frequency algorithms are used. With a system like the FNET, it has been
demonstrated that power system frequency can be accurately measured, given accurate
time synchronization, and sampling of signals at distribution voltage levels [6].
Eventually, the FNET will offer the possibility of enhancing monitoring, protection, and
control functions for electric power systems [7]. A diagram of the FNET system can be
seen below in Fig. 1.
Figure 1 – Diagram of the overall FNET system
FDR units execute frequency calculations using algorithms of phasor analysis and signal
resampling techniques. Frequency estimation algorithms developed for FNET have
virtually no algorithm error in the frequency range of 52 Hz to 70 Hz. In the current
generation FDR, the complexity of the frequency calculations is minimized to allow the
onboard microcontroller time to complete its other tasks, such as network data output and
servicing interrupts, in order to prevent data overflow. The current version of the FDR
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