The industry is already working for quite a while on the issue
of measuring the phasors of the quantities in the electrical
power system. A first standard on this issue, IEEE 1344 [6]
was available since 1995.
Phasor Measurement Units (PMUs) were already available
in 2003, when the big blackouts in the north-east of the USA
and in Italy gave this technology a big boost. The PMUs
became recognized as an effective tool for observing the
status of the power network and ensuring its stability. Shortly
after the dramatic events, the Eastern Interconnect Phasor
Project (EIPP) [4] was founded with the focus to apply wide
area measurement, monitoring and control for improving the
reliability of the power system. The activities of the EIPP will
be continued by the North American SynchroPhasor Initiative
(NASPI) [8]. In Europe, the UCTE is also using wide area
monitoring with PMUs for observing the status of the network
[10].