Page 12 - excerpts ELP

Phasor Measurement Units, GPS, and Wide Area Management Systems
Phasor measurement units, also called syncrophasors, are strategically located in substations that interconnect the generators and transmission systems together. They can check the phase angle on the voltage and current waves, as often as 30 times per second, and automatically trigger the operation of key substation equipment such as capacitors and reactors to operate when there are disturbances to the phase angles. They can also be networked with phasor measurement units from other substations through global positioning systems, allowing all phasor measurement units in the network to operate in unison. This is referred to as a Wide Area Management System, and results in much more e cient and uniform transmission grid.
FOSSIL FUEL GENERATION
500 kV
500 kV
AC-DC-AC Back-to-Back Tie
TRANSMISSION SUBSTATION
Phasor measurement units (PMUs) communicate via satellite to work in unison.
PMU
INTRODUCTION TO SMART GRID | CHAPTER THREE
PMU (inside control house)
PMU (inside control house)
23
30 kV
13
230 kV
1
8 8
V V
SUBTRANSMISSION SUBSTATION
Satellite
NORTHWEST LINEMAN COLLEGE 69
1
V
38
8k
k
V
1
3
k
3
k