風力發(fā)電機畢業(yè)論文英文文獻翻譯

1、風力發(fā)電機畢業(yè)論文英文文獻翻譯附錄一 英文文獻Wind Energy Introduction1.1 Historical DevelopmentWindmills have been used for at least 3000 years, mainly for grinding grain or pumping water, while in sailing ships the wind has been an essentia

2、l source of power for even longer. From as early as the thirteenth century, horizontal-axis windmills were an integral part of the rural economy and only fell into disuse with the advent of cheap fossil-fuelled engines

3、and then the spread of rural electrification.The use of windmills (or wind turbines) to generate electricity can be traced back to the late nineteenth century with the 12 kW DC windmill generator constructed by Brush in

4、the USA and the research undertaken by LaCour in Denmark. However, for much of the twentieth century there was little interest in using wind energy other than for battery charging for remote dwellings and these low-powe

5、r systems were quickly replaced once access to the electricity grid became available. One notable exception was the 1250 kW Smith–Putnam wind turbine constructed in the USA in 1941. This remarkable machine had a steel ro

6、tor 53 m in diameter, full-span pitch control and flapping blades to reduce loads. Although a blade spar failed catastrophically in 1945, it remained the largest wind turbine constructed for some 40 years (Putnam, 1948)

7、.Golding (1955) and Shepherd and Divone in Spera (1994) provide a fascinatinghistory of early wind turbine development. They record the 100 kW 30 m diameterBalaclava wind turbine in the then USSR in 1931 and the Andrea E

8、nfield 100 kW 24 m diameter pneumatic design constructed in the UK in the early 1950s. In this turbine hollow blades, open at the tip, were used to draw air up through the tower where another turbine drove the generato

9、r. In Denmark the 200 kW 24 m diameter Gedser machine was built in 1956 while Electricite´ de France tested a 1.1 MW 35 m diameter turbine in 1963. In Germany, Professor Hutter constructed a number of innovative,

10、lightweight turbines in the 1950s and 1960s. In spite of these technical advances and the enthusiasm, among others, of Golding at the Electrical Research Association in the UK there was little sustained interest in wind

11、 generation until the price of oil rose dramatically in 1973.The sudden increase in the price of oil stimulated a number of substantialGovernment-funded programmes of research, development and demonstration. In the USA

12、 this led to the construction of a series of prototype turbines starting with the 38 m diameter 100 kW Mod-0 in 1975 and culminating in the 97.5 m diameter 2.5 MW Mod-5B in 1987. Similar programmes were pursued in the U

13、K, Germany and Sweden. There was considerable uncertainty as to which architecture might prove most cost-effective and several innovative concepts were investigated at full scale. In Canada, a 4 MW vertical-axis Darrie

14、us wind turbine was constructed and this concept 風力發(fā)電機畢業(yè)論文英文文獻翻譯considerable state support, were constructing much smaller, often simpler,turbines for commercial sale. In particular the financial support mechanisms in Ca

15、lifornia in the mid-1980s resulted in the installation of a very large number of quite small(<100 kW) wind turbines. A number of these designs also suffered from various problems but, being smaller, they were in ge

16、neral easier to repair and modify. The so-called 'Danish' wind turbine concept emerged of a three-bladed,stall-regulated rotor and a fixed-speed, induction machine drive train. This decep-tively simple architectu

17、re has proved to be remarkably successful and has now been implemented on turbines as large as 60 m in diameter and at ratings of 1.5 MW. The machines of Figures 1.1 and 1.2 are examples of this design. However, as the

18、 sizes of commercially available turbines now approach that of the large prototypes of the 1980s it is interesting to see that the concepts investigated then of variable-speed operation, full-span control of the blades,

19、 and advanced materials are being used increasingly by designers. Figure 1.3 shows a wind farm of direct-drive, variable-speed wind turbines. In this design, the synchronous generator is coupled directly to the aerodyna

20、mic rotor so eliminating the requirement for a gearbox. Figure 1.4 shows a more conventional, variable-speed wind turbine that uses a gearbox, while a small wind farm of pitch-regulated wind turbines, where full-span con