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1、Wind Power Presentation:1. Climate Change & Renewable Energy2. Historical Developments3. Modern Technology4. Penetration of Wind EnergyDr. Dharshana MuthumuniSeptember 20091. Climate Change & Renewable EnergyCLIMATE CHANGE AND RENEWABLE ENERGYExtract from a ENGLISH HERITAGE reportThe Earths climate

2、is changing. The average global temperature has risen by 0.6 degrees Celsius since the beginning of the 20th century, taking the northern hemisphere outside the range of average temperatures it has experienced over the last 1,000 years. Globally, all of the 10 warmest years on record have occurred s

3、ince the beginning of the 1990s, and the effects of recent warming can be seen in an increased incidence of heat-waves, storminess and flooding, the retreat of glaciers and ice sheets, and altered responses in plants and animals.Although climate change is a natural and constant process, there is a s

4、trong scientific and political consensus, internationally and within the UK, that the current increase in average temperatures results mainly from increasing atmospheric concentrations of carbon dioxide and other greenhouse gases and that these increasing concentrations are the result, in part at le

5、ast, of human influences. There is also general agreement that average temperatures are likely to rise even faster, particularly in the second half of this century, unless action is taken to limit and reduce greenhouse gas emissions. Under the terms of the Kyoto Protocol, the UK pledged to reduce gr

6、eenhouse gas emissions by 12.5 per cent below 1990 levels by 200812, with a further undertaking to reduce CO2 emissions by 20 per cent by 2010. The European Union has also endorsed the need to reduce carbon dioxide levels in order to limit future temperature rise to 2 degrees Celsius.CLIMATE CHANGE

7、AND RENEWABLE ENERGYThe Earths climate is changingGlobally, all of the 10 warmest years on record have occurred since the beginning of the 1990sClimate change is a natural and constant process, but, increasing atmospheric concentrations of greenhouse gases has influenced the processThe need to reduc

8、e carbon dioxide levels in order to limit future temperature riseWIND ENERGYConverting wind energy into electricity reduces the environmental impact of power generationWind is currently the most developed of renewable energy technologiesWIND TURBINES Rapidly advancing in technology Ratings increased

9、 from 200 kW to 3 MW (% MW emerging) in the last decade Over 30 m blade radius Close to 100 m tower heights Wind farms integrated to the main grid Land sites and off shore sites Technology is advancing2. Historical Developments May have been in use for over 3000 years Water pumping Grain grinding Fi

10、rst proof of use: Persia in around 500-900 A.D. Wind tracking done from very early days Automated tracking in the 1700s Variable speed operation in 1700sAmerican wind mill of late 1800s The first use of a large windmill Ohio,1888 Rotor 17 meters in diameter Large tail hinged to turn the rotor out of

11、 the wind First windmill to incorporate a step-up gearbox (ratio 50:1) DC generator operated at 500 rpm1888: Brush wind turbineHowever:By 1920s air plane industry influenced the wind blade designs Aircraft wing profiles considered for wind turbine blades Variable speed operation in 1700s1977 design

12、with pitch mechanismsEarly 20th century: Electricity affected wind developments Bulk power generation: 100 kW unit in Russia in 19311.25 MW unit in USA in 1941Horizontal axis2 Bladeover 50 m rotor diameter16 ton rotor28 rpm, Synchronous machineFailed in 1945: Blades broke off due to metal fatigue1.2

13、5 MW Smith-Putnam machine In North America the wind turbine developments slowed down after the 1930s European developments continued at an much elevated rate Oil crisis in the early 1970s injected new life into wind power research and development Lessons and knowledge from the long past was not all

14、lostProposed 1970s GE turbineDifferent designs were considered in R&DMulti Mega-Watt Units: Developments started in the late 1980s but almost died by early 1990s. The need for Green power :Developments resumed in the late 1990s. A Colorado Wind Farm3. Modern TechnologyLarge turbines of 5 MWOver 100

15、m DiameterOver 150 m tallSophisticated aerodynamic designAdvanced technology for off-shore installationsEnergy cost is decreasingAdvanced materialLightweight, strongerGenerator conceptsDFIGPM MachineControl methodologyP and Q controlPitchingWind predictionTransportation and constructionMain componen

16、tsGE 3.6 MWWind speed: 3.5 14 25 m/sDFIG :IGBT basedSpeed : 8.5 15.3 rpmBlade Dia:111 m GE 3.6 MWVestas V90Vestas V90 3 MWWind speed: 4 15 25 m/sDFIG :Opti-speedSpeed : 8.6 16.1 -18.4 rpmBlade Dia:90 m Gamesa - G90Blade Dia:90 m Gamesa - G90Aerodynamic primary brake by means of full-feathering blade

17、sHydraulically-activated mechanical disc brake for emergencies690 V Stator4 pole machineGear ratio - 1:120.5 material: Pre-impregnated epoxy glass fibre with carbon fibberEnercon E82 Direct drive synchronous generator Pitch control Back- to- back converter grid coupled 6- 19.5 rpm Storm control feature4. Penetration of