1 / 0

ECE 530 – Analysis Techniques for Large-Scale Electrical Systems

ECE 530 – Analysis Techniques for Large-Scale Electrical Systems. Lecture 2: Power Systems Overview. Prof. Tom Overbye Dept. of Electrical and Computer Engineering University of Illinois at Urbana-Champaign overbye@illinois.edu. About Me. Professional

marged
Download Presentation

ECE 530 – Analysis Techniques for Large-Scale Electrical Systems

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. ECE 530 – Analysis Techniques for Large-Scale Electrical Systems

    Lecture 2: Power Systems Overview Prof. Tom Overbye Dept. of Electrical and Computer Engineering University of Illinois at Urbana-Champaign overbye@illinois.edu
  2. About Me Professional Received BSEE, MSEE, and Ph.D. all from University of Wisconsin at Madison (83, 88, 91) Worked for eight years as engineer for an electric utility (Madison Gas & Electric) Have been at UI since 1991, doing teaching and doing research in the area of electric power systems Developed commercial power system analysis package, known now as PowerWorld Simulator. This package has been sold to about 600 different corporate entities worldwide DOE investigator for 8/14/2003 blackout
  3. About Prof. Tom Overbye Nonprofessional Married to Jo Have three children Tim age 18 Hannah age 16 Amanda age 14 Live in country by Homer We’ve homeschooled ourkids all the way through, with Tim now startingat UIUC!
  4. My Kids
  5. Course Syllabus Course mechanics and topics Introduction Analysis of nonlinear electrical systems, with detailed coverage of power flow and related issues Data and computational issues associated with large-scale systems including sparsity and visualization Nonlinear parameter estimation in electrical systems Modeling for dynamic analysis including time scale separation and modal analysis Dynamic performance analysis including solution of differential-algebraic systems
  6. Graduate School Sources of Info: Books, journals, conferences, and real-life How to read a paper
  7. Simple Power System Every power system has three major components generation: source of power, ideally with a specified voltage and frequency load: consumes power; ideally with a constant resistive value transmission system: transmits power; ideally as a perfect conductor
  8. Complications No ideal voltage sources exist Loads are seldom constant Transmission system has resistance, inductance, capacitance and flow limitations Simple system has no redundancy so power system will not work if any component fails
  9. Notation - Power Power: Instantaneous consumption of energy Power Units Watts = voltage x current for dc (W) kW – 1 x 103 Watt MW – 1 x 106 Watt GW – 1 x 109 Watt TW – 1 x 1012 Watt Installed U.S. generation capacity is about 900 GW ( about 3 kW per person) Maximum load of Champaign/Urbana about 300 MW
  10. Notation - Energy Energy: Integration of power over time; energy is what people really want from a power system Energy Units Joule = 1 Watt-second (J) kWh – Kilowatthour (3.6 x 106 J) MWh – One MW for one hour TWh – One million MWh Btu – 1055 J; 1 MBtu=0.292 MWh U.S. electric energy consumption is about 4000 TWh kWh (about 12,500 kWh per person, which means on average we each use 1.4 kW of power continuously)
  11. Notation and Voltages The IEEE standard is to write ac and dc in smaller case, but it is often written in upper case as AC and DC. Three-phase is usually written with the dash, also as 3-phase. In the US the standard household voltage is 120/240, +/- 5%. Edison actually started at 110V dc. Other countries have other standards, with the European Union recently standardizing at 230V. Japan’s voltage is just 100V.
  12. Power System Examples Electric utility: can range from quite small, such as an island, to one covering half the continent there are four major interconnected ac power systems in North American, each operating at 60 Hz ac; 50 Hz is used in some other countries. Airplanes and Spaceships: reduction in weight is primary consideration; frequency is 400 Hz. Ships and submarines Automobiles: dc with 12 volts standard Battery operated portable systems
  13. North America Interconnections
  14. Electric Transmission System
  15. Electric Systems in Energy Context Class focuses on electric power systems, but we first need to put the electric system in context of the total energy delivery system Electricity is used primarily as a means for energy transportation Use other sources of energy to create it, and it is usually converted into another form of energy when used About 40% of US energy is transported in electric form Concerns about need to reduce CO2 emissions and fossil fuel depletion are becoming main drivers for change in world energy infrastructure
  16. Sources of Energy - US About 40% of our energy is consumed in the formof electricity, a percentagethat is gradually increasing.The vast majority of the non-fossil fuel energy is electric! In 2012 we got about 1.4% of our energy from wind and 0.04% from solar (PV andsolar thermal) About 84% Fossil Fuels 1 Quad = 293 billion kWh (actual), 1 Quad = 98 billion kWh (used, taking into account efficiency) Source: EIA Annual Energy Outlook 2013, Electric Power Monthly, July 2013
  17. US Historical and Projected Energy Usage Projections say we will still be 78% fossil in 2040! Source: EIA Annual Energy Outlook 2013
  18. Worldwide Energy Usage Source: EIA International Energy Outlook, 2013
  19. 1980-2011 Energy by Region million toe Latin America North America Former Soviet Union Asia Middle East Europe Africa
  20. Variation In Electricity Sources
  21. Electric Energy Economics Electric generating technologies involve a tradeoff between fixed costs (costs to build them) and operating costs Nuclear and solar high fixed costs, but low operating costs Natural gas/oil have low fixed costs but high operating costs (dependent upon fuel prices) Coal, wind, hydro are in between Also the units capacity factor is important to determining ultimate cost of electricity Potential carbon “tax” seen as unlikely soon
  22. Ball park Energy Costs Nuclear: $15/MWh Coal: $22/MWh Wind: $50/MWh Hydro: varies but usually water constrained Solar: $120 to 180/MWh Natural Gas: 8 to 10 times fuel cost in $/MBtu Note, to get price in cents/kWh take price in $/MWh and divide by 10.
  23. Natural Gas Prices 1990’s to 2013 Marginal cost for natural gas fired electricity price in $/MWh is about 7-10 times gas price
  24. Key Driver for Renewables: Concerns about Global Warming Value wasabout 280ppm in 1800; in 2013 it is 396 ppm Source: http://www.esrl.noaa.gov/gmd/ccgg/trends/
  25. Worldwide Temperature Graph Baseline is 1961 to 1990 mean Source: http://www.cru.uea.ac.uk/cru/info/warming/
  26. Looking Back a Little Further With lots more uncertainty! Source: http://www.econ.ohio-state.edu/jhm/AGW/Loehle/SupplementaryInfo.pdf
  27. Going Back Further it Was Mostly Cold! http://commons.wikimedia.org/wiki/File:Ice_Age_Temperature.png
  28. natural forcing only anthropogenic forcing only natural +anthropogenic forcing Compelling Evidence? natural (solar + volcanic) forcing alone does not account for warming in the past50 years "With four parameters I can fit an elephant and with five I can make him wiggle his trunk." — John von Neumann adding human influences (greenhouse gases + sulfate aerosols) brings the models and observations into pretty close agreement Source: Prof. Gross Fall 2013 ECE 333 Notes
  29. And Where Might Temps Go? The modelsshow rate of increase valuesof between0.18 to 0.4 C per decade.The rate from1975 to 2005was about 0.2 C per decade. Source: http://www.epa.gov/climatechange/science/future.html#Temperature
  30. Brief History of Electric Power Early 1880’s – Edison introduced Pearl Street dc system in Manhattan supplying 59 customers within a one mile radius 1884 – Sprague produces practical dc motor 1885 – invention of transformer Mid 1880’s – Westinghouse/Tesla introduce rival ac system Late 1880’s – Tesla invents ac induction motor 1893 – First 3-phase transmission line operating at 2.3 kV, 12 km in Southern California
  31. History, cont’d 1896 – ac lines deliver electricity from hydro generation at Niagara Falls to Buffalo, 20 miles away Early 1900’s – Private utilities supply all customers in area (city); recognized as a natural monopoly; states step in to begin regulation By 1920’s – Large interstate holding companies control most electricity systems; highest voltages were 200 kV
  32. History, cont’d 1935 – Congress passes Public Utility Holding Company Act to establish national regulation, breaking up large interstate utilities (repealed 2005) 1935/6 – Rural Electrification Act brought electricity to rural areas 1930’s – Electric utilities established as vertical monopolies
  33. Generation Transmission Distribution Customer Service Vertical Monopolies Within a particular geographic market, the electric utility had an exclusive franchise In return for this exclusive franchise, the utility had the obligation to serve all existing and future customers at rates determined jointly by utility and regulators It was a “cost plus” business
More Related