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Why are Synchrophasors Important? Here’s All You Need to Remember Average Power Flow P Through a Mostly Inductive Transmission Line (138kV and above). + ─. + ─. ground. Charles Steinmetz, developed phasor theory to analyze AC circuits. For small x, sin(x) = x. These are about 1pu.
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Why are Synchrophasors Important? Here’s All You Need to Remember Average Power Flow P Through a Mostly Inductive Transmission Line (138kV and above) + ─ + ─ ground Charles Steinmetz, developed phasor theory to analyze AC circuits For small x, sin(x) = x These are about 1pu Stability limit is when the angle difference reaches 90 degrees
Western and Eastern Nebraska • Two in Kansas City area • Little Rock • N.E. Texas (Eastern Grid) • Washington D.C. area • Texas Panhandle (Eastern Grid) • Idaho National Lab • Colorado Springs • Los Alamos Nat. Lab • Cloudcroft, NM (near White Sands Nat’l Monument) BAYLOR 410 miles McDONALD OBSERVATORY Waco Brazos Electric Coop 370 miles • Austin – 3M • DFW area • Houston 460 miles UT PAN AM
PMU Station Equipment Three 50 ft. (or two 75 ft.) pieces of RG-6 coax with TNC male connectors. A mail-to-mail TNC-TNC adapter is on one end of two of the cables. SEL2890 Internet transceiver screwed to Port 3 Terminated T-BNC fits on left BNC jack 120V hot and neutral are jumpered over to phase A inputs. SEL2401 satellite clock receives RG-6 from GPS antenna, and connects to SEL421 through a small coax. 15 ft. RG-6. One end connects to GPS antenna, the other end to a lightning arrestor. Ground the arrestor. Power supply for satellite clock. GPS antenna screws onto ¾” threaded male-to-1” smooth PVC adapter, which in turn slides into a 1” coupling. A 1” PVC pipe slides into the other end of the coupling. You may want to use a longer pipe to get a good sky view.
This is probably the world’s first electricity market-induced grid oscillation! 12 hour window ERCOT’s graph of West-to-North P flow Price went down, then wind gens responded, then price went up, then wind gens responded, • • • Texas Synchrophasor Network’s graph of West-to-Central ERCOT Voltage Angle Candidate for Ripley’s Believe It or Not? 12-hour window
ERCOT SPP Omaha, NE, area. Lost signal on Wednesday WECC Internet dropouts at the Cloudcroft, NM, mountain cabin cause the sparse appearance of this graph All Three Grids Had Problems This Week