Blackouts EE 521 Analysis of Power Systems Chen-Ching Liu Boeing Distinguished Professor Washington State University
Catastrophic Power Outages
Sabotage OkC Oak Creek kwisconsin i October 11 th 2004 American Transmission Company- Two transmission towers were toppled by removing bolts in the support legs and their cross members. This resulted in Mitchell International Airport & 17,000 area residents losing power.
North East Power Grid November 9 th, 1965 Blackout 5:16 p.m. 1 of 5 230-kV lines supplying power to Ontario trips due to a incorrectly set backup over current relay. Generators at Beck and dniagara speed up due to rapid unloading and are soon out of phase with the rest of the system. The East Coast Interconnect t separates into 4 areas with massive load loss. 30 million people lost power. The readjustment of power to the other 4 230- kv lines causes their backup relays to operate. Tie lines to neighboring systems are severed because of instability. Approx. 1800 MW was flowing East and South through the NW system. 1.33 seconds after the initial load separation the 2 230-kV lines connecting the PANSY plant with the 345-kV trunk lines feeding New York and New England are tripped. MN VT ME Approx. 1500MW of power that had been flowing into Ontario, surges into the NY system creating instability. 5 additional generators trip due to the loss of trunk lines. This initiates the separation of the East Coast Interconnect. KS OK IA MO WI IL MI IN KY TN OH WV NH NY MA CT RI PA NJ DE MD VA NC AR SC MS AL GA LA FL
North East Power System July 13 th, 1977 Blackout 8:37:17 p.m. initial iti lighting strikes remove the W97 and W98 345-kV lines from service, additionally this isolated the Indian point no. 3 Nuclear Plant. 8:55:53 p.m. additional lighting strikes remove the W93/W79 and W99/W64 345-kV lines from service. 9:19:11 p.m. due to overloading the 345-kV line 92 from Niagara sags and contacts a tree isolating 1,202 MW of generation. 92941Th 9:29:41 The Consolidated dedison system becomes isolated from the rest of the Eastern Interconnect. At the time of separation the total Con Edison load was 5,981MW while generation was only 4,282 MW, a deficiency i of 1,680 MW. Immediate load shedding and generation increase was needed. Under frequency load shedders operated automatically at three levels; 59.3, 58.8, and 58.3 Hz. This shed 2,230.6 MW of load. With the loss of the Ravenswood No.3 Generator, and its 844 MW of output, the entire Con Edison system collapsed. 9 million people lost power. MN IA WI IL IN MI OH PA NY NJ DE MD VT NH MA CT RI ME 9:19:53-9:29:41 a series of equipment malfunctions and operator errors lead to the isolation of the Consolidated d Edison system. Once the load was shed, voltage rapidly increased due to extensive underground 138- kv and 345-kV lines resulting in the tripping of the Ravenswood No. 3 Generator. KS OK MO AR LA MS TN AL KY WV VA NC SC GA FL
Western Electric Coordinating Council (WECC) system - July 2 nd, 1996 Blackout 224 2:24 p.m. Jim Bridger-Kinport Bid 345-kV line is tripped due to sag. Due to a faulty relay the parallel Jim Bridger-Goshen also trips. 2 of the 4 generators at the Jim Bridger disconnected by a Remedial Action Scheme. Mill Creek-Antelope 230-kV line trips due to a faulty Zone 3 relay. Voltage in the Boise Idaho area as well as voltage on the COI began to rapidly collapse. Within 8 seconds of the initial iti event, 5 asynchronous islands had been formed. 2 million people lost power. The loss of 2 parallel lines was considered a single contingency event, and as such the system was able to handle the loss of 2 345-kV lines and the associated loss of generation. For approx. 23 seconds the system seems to handle the events properly despite minor voltage fluctuations. Then a faulty relay destabilized the system. Due to collapsing voltages 4 230-kV lines between Boise and the Brownlee substation tripped. Further, protective devices at the Malin and Captain Jack substations in southern Oregon automatically disconnected the COI. Disconnecting i the COI interrupted 4,000 MW of power flow and separated the WECC. CA WA OR NV ID AZ UT MT WY CO NM
Western Electricity Coordinating Council (WECC) system stem - Aug 10 th, 1996 Blackout 15:48 p.m. Keeler-Allston 500-kV line contacts a tree due to inadequate right-of-way maintenance. Additionally the Pearl-Keeler line is forced out of service due to the Keeler 500/230-Kv transformer being OOS. Mild.224 Hz oscillations were seen throughout the system and began to appear on of the PDCI. Shunt capacitor banks were switched in to raise the voltage but the oscillations were not bi being damped. d The WECC broke into 4 asynchronous islands with heavy loss of load. 7.5 million people lost power. With the loss of these 2 lines, 5 lines are now out of service, removing hundreds of MVAR. 15:48:51 p.m. Oscillations on the POI reached 1000MW and 60-kV peak-to-peak. WA MT Lines throughout the system begin to experience overloads as well as low voltage conditions. Additional lines trip due to sagging. PDCI Remedial Action Schemes (RAS) began to actuate. Shunt and series capacitors were inserted. CA OR NV ID UT WY CO 15:47:40-15:48:57 p.m. Generators at the McNary power house supplying 494 MVAR trip. The system begins to experience mild oscillations. AZ NM
Eastern Interconnection h August 14 th, 2003 Blackout 1:07 p.m. FE turns off their state estimator for troubleshooting. 4:05:57 p.m. The loss of 138-kV lines overloads the Sammis-Star line. 265 power plants tripped off line and 50 million people are without power. 1:31 p.m. Eastlake 5 generation unit trips and shuts down. 2:02 p.m. Stuart-Atlanta 345-kV line tips off due to contact with a tree. 4:08:59 p.m. Galion-Ohio and Central- Muskinghun 345-kV lines trip on Zone 3 causing major power swings through New York and Ontario and into Michigan. 2:14 p.m. FE s control room lost alarm functions followed by a number of the EMS consoles. 2:54 p.m. The primary and secondary alarms servers failed. Low voltage/ high load conditions and system disturbances propagate through the system tripping transmission lines and generators. KS MN IA MO WI IL MI IN KY OH WV ME VT NH NY MA CT RI PA NJ DE MD VA 3:05:41-3:57:35 p.m. 3 345-kV lines trip due to contact with trees. This overloads the underlying 138-kV system and depressed voltages. 4:13 p.m. most of the North East and parts of Canada blacked out. There are only a few islands which remain operating. OK AR LA MS TN AL GA NC SC FL 3:39:17-4:08:59 p.m. 16 138-kV lines trip due to overloading.