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Guided Tour

By Jeanne Nichols,2014-12-05 05:10
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Therefore, alternative techniques had to be developed in order to break through the cost barrier, as we shall see on the next pages.

    Guided Tour

    风电入门

     ——Danish Wind Industry Association

     ——丹麦风电工业协会风电指导用书

    Wind .................................................................................................................................... 5

    Whence wind? 风是从哪里来的, ............................................................................... 5 The coriolis force 克里奥利力 ...................................................................................... 7 Global winds 全球风 ...................................................................................................... 8 Geostrophic wind 地转风 ............................................................................................ 10 Local winds局域风 ....................................................................................................... 11 Mountain winds山地风 ................................................................................................ 13 Energy in the wind 风能 .............................................................................................. 14 Wind deflection 风的偏转 ......................................................................................... 16 Anemometers 风速计 .............................................................................................. 21 Measurement in practice 实际测量 ......................................................................... 24 The wind rose 风玫瑰图 ............................................................................................ 26 Draw a wind rose 画风玫瑰图 .................................................................................. 31

    Turbine sitin 风机选址 .......................................................................................................... 34 Roughness & shear 粗糙度与风剪切 ...................................................................... 34

    Speed calculation 速度计算 ....................................................................................... 38 Escarpments 陡坡 ..................................................................................................... 42 The roughness rose 粗糙度玫瑰图 ......................................................................... 44 Variable winds 可变风 ............................................................................................... 46 Turbulence 湍流 ......................................................................................................... 48 Wind obstacles 风障碍物 .......................................................................................... 49 Wind shade 风影 .......................................................................................................... 52 Calculator guide 计算器指南 .................................................................................... 54 Shade calculator 风影计算器 ................................................................................... 61 Wake 尾流 ................................................................................................................... 63 The park effect 风场效应 .......................................................................................... 65 The tunnel effect 风洞效应 ....................................................................................... 67 The hill effect 山丘效应 ........................................................................................... 69 Turbine siting风机选址 ........................................................................................... 71

    选择一处风机场址 ........................................... 71

    Offshore winds 海上风能 ............................................................................................ 74 Wind map Europe 欧洲风图 ....................................................................................... 77 Wind map Denmark 丹麦的风图.............................................................................. 80

    Energy output 能量输出 ...................................................................................................... 84 The Weibull distribution 威布尔分布 ....................................................................... 84 Distribution plotting 分布绘图 ..................................................................................... 87 The average bottle fallacy 平均的瓶形谬误 ........................................................... 88

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Mean power of the wind 平均风功率 ...................................................................... 90

    Betz' law 贝兹定律 ..................................................................................................... 92 Power density 功率密度 ............................................................................................ 94 Power curves 功率曲线............................................................................................. 97 The power coefficient 功率系数 ........................................................................... 101 Calculator guide 计算器指南 .................................................................................. 103 The power calculator 功率计算器 .......................................................................... 112 Annual energy output 年度能量输出 ..................................................................... 116

    How does it work? 风力发电机是如何工作的, ............................................................... 120

    Components部件 ....................................................................................................... 120 Lift 升力 ....................................................................................................................... 120 Stall and drag失速和阻力 ......................................................................................... 122 Sum of wind speeds风速的总和 .............................................................................. 123 Rotor aerodynamics 转轮空气动力学 ..................................................................... 125

    Rotor blades 转轮叶片 .............................................................................................. 127 Power control功率控制 ............................................................................................. 129 The yaw mechanism 偏航机构 ................................................................................ 135 Towers 塔架 ................................................................................................................ 137 The size of turbines 风机尺寸 .................................................................................. 142 Turbine Safety 风机的安全 ....................................................................................... 146 Labour safety 职业安全............................................................................................. 150

    Generators发电机 ................................................................................................................ 152 Generators发电机 ...................................................................................................... 152 Synchronous machines同步机 ................................................................................ 155 No. of poles极对数 .................................................................................................... 159 Asynchronous machines异步机 .............................................................................. 161 Changing no. of poles改变极数 ............................................................................... 166 Variable slip可变滑差 ................................................................................................ 169 Indirect grid connection间接电网连接..................................................................... 173

    Gearboxes齿轮箱 ...................................................................................................... 177 Controllers控制器 ...................................................................................................... 179 Power quality电能质量 .............................................................................................. 182

    Turbine design涡轮机设计 .................................................................................................. 185 Load considerations载荷考虑 .................................................................................. 185 Horizontal/vertical水平/竖直 ..................................................................................... 189 Upwind/downwind上风向/下风向............................................................................. 192 No. of rotor blades转轮叶片数量 ............................................................................. 194 Optimising turbines优化涡轮机 ................................................................................ 197 Low mechanical noise低机械噪声........................................................................... 199 Low aerodynamic noise低气动噪声 ........................................................................ 202

    Manufacturing制造业 .......................................................................................................... 206 Nacelles机舱 .............................................................................................................. 206 Blade testing叶片测试 ............................................................................................... 206 Towers塔架 ................................................................................................................. 211

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    Welding towers焊接塔架........................................................................................... 214 Installing towers安装塔架 ......................................................................................... 215 Offshore foundations海上基础 ................................................................................. 217

    R & D研究与开发 ............................................................................................................... 220 R & D in wind风力的研究与开发 .............................................................................. 220 Research in offshore海上研究 ................................................................................. 222 Foundations at sea海上基础 .................................................................................... 225 Concrete caissons混凝土沉箱 ................................................................................. 227 Steel gravitaty foundations钢重力基础 ................................................................... 229 Monopile foundations单桩基础 ................................................................................ 232 Tripod foundations三脚架基础 ................................................................................. 234

    Electrical grid电网 ............................................................................................................... 236 Variations in energy能量变化 ................................................................................... 236 Seasonal variations季节性变化 ............................................................................... 238 Power quality电能质量 .............................................................................................. 239 Offshore wind and grid海上风力和电网 .................................................................. 245

    Environment环境 ................................................................................................................. 249 Landscape and turbines景观与风力机 ................................................................... 249 Aerial markings航空标志 ............................................................................................ 252 Sound from turbines风力机的声音 ............................................................................. 258 Sound measurement声音测量 ..................................................................................... 262 Sound map calculator 声音图计算器 ........................................................................ 268 Sound calculator 声音计算器 ...................................................................................... 269 Energy balance 能量平衡 ............................................................................................ 271 Birds and wind turbines 鸟类和风力机....................................................................... 273 Birds and offshore wind鸟类和海上风力 ................................................................... 275 Shadow casting 投影.................................................................................................... 278 Shadow calculation阴影计算 ...................................................................................... 281 Better calculations更好的计算 ................................................................................... 283 Shadow variations阴影变化 ........................................................................................ 287 Guide to calculator计算器指南 ................................................................................... 290 Shadow calculator 阴影计算器 ................................................................................... 301

    Economics 经济性 ............................................................................................................... 308 Turbine costs 风力机成本 ........................................................................................... 308 Turbine installation 风力机安装,................................................................................. 310 O & M 运行和维护 ..................................................................................................... 312 Income from wind energy 风能的收入 ....................................................................... 315 Tariffs 价目表 .............................................................................................................. 317 Investment in wind power 风电的投资 ....................................................................... 321 Economics of wind energy 风能经济学 ...................................................................... 325 Traps in analyses 分析中易犯的错误 ......................................................................... 328 Guide to the calculator 计算器指南 ............................................................................ 339 Economics calculator 经济学计算器 .......................................................................... 344 Economics of offshore wind 海上风力的经济性 ........................................................ 348

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    Employment 就业 ........................................................................................................ 350

    History of wind energy 风能的历史 .................................................................................... 354 Introduction 前言 .................................................................................................... 354 Charles F. Brush 查尔斯弗朗西丝布拉什?Charles Francis Brush? ......... 355

    Poul la Cour 保罗?拉?库尔?Poul la Cour? ................................................. 364

    1940-1956.................................................................................................................... 367 Johannes Juul 约翰内斯?尤尔 ........................................................................... 368 1980s 20世纪80年代 .......................................................................................... 371 The great wind rush 浩大的风能潮...................................................................... 375

    Modern wind turbines 现代风力机 ....................................................................... 377 Offshore wind turbines 海上风力机 ..................................................................... 378

    Megawatt turbines 兆瓦级风力机 ........................................................................ 385 Multi mega machines 多兆瓦级风力机 ............................................................... 387

    Wind energy manual 风能手册 ....................................................................................... 390 Index 索引 ............................................................................................................... 390 Wind energy concepts 风能概念 ......................................................................... 393 Energy and power 能量和功率 ............................................................................ 400 Proof of Betz' law 贝兹定律的证明 ...................................................................... 405 Wind turbine acoustics 风力机声学 ..................................................................... 407

    Electricity ............................................................................................................ 411 3 phased electricity 3相交流电 ........................................................................... 415 3 phased connection 3相连接形式 ..................................................................... 416

    Electromagnetism 1 电磁效应1 .......................................................................... 418 Electromagnetism 2 电磁效应2 .......................................................................... 419 Induction 1 感应1 .................................................................................................. 419 Induction 2 感应2 .................................................................................................. 420 Environment and fuels 环境与燃料 ..................................................................... 421

    Bibliography 参考文献 ........................................................................................... 423 Glossary 词汇表 ..................................................................................................... 427

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Wind

    Whence wind? 风是从哪里来的,

    风是从哪里来的,

    All renewable energy (except tidal and geothermal power), and even the energy in fossil fuels, ultimately comes from the sun. The sun radiates 174,423,000,000,000 kilowatt hours of energy to the earth per hour. In other

    17 1) words, the earth receives 1.74 x 10 watts of power .

    所有可再生能源?潮汐能与地热能除外?(即使是矿物能源(最终都来自于

    太阳。每小时太阳辐射174,423,000,000,000KWh的能量到地球上来。换句话

    171说(地球接受1.74?10W的功率

    About 1 to 2 per cent of the energy coming from the sun is converted into wind energy. That is about 50 to 100 times more than the energy converted into

    2) biomass by all plants on earth.

    来自太阳的能量(大约有1-2%转换成风能。约为地球上所有植物将太阳能

    2转换成生物质能的50-100

    温差驱

    动空气流动

    The regions around equator, at 0? latitude are

    heated more by the sun than the rest of the globe.

    These hot areas are indicated in the warm colours, red, orange and yellow in this infrared picture of sea surface temperatures (taken from a NASA satellite, NOAA-7 in July 1984).

    在赤道地区(即0?纬度地区(太阳加热超过地球上的其他地区。下图给出

    了海洋表面温度的红外照片?取自NASA的卫星图片, NOAA-7,19847月?(

    暖色(红色、橘黄色和黄色(表明了受热区域。

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    Hot air is lighter than cold air and will rise into the sky until it reaches approximately 10 km (6 miles) altitude and will spread to the North and the South. If the globe did not rotate, the air would simply arrive at the North Pole and the South Pole, sink down, and return to the equator.

    热空气比冷空气轻(将升上天空(直到升至大约10公里?6英里?的高度(

    然后向南北半球扩散。如果地球不旋转(空气就会简单地到达北极和南极(然后

    下降(最后又回到了赤道。

    2 1) The power emission from the sun is 1.37 kW/m on the surface of

    the sphere, which has the sun as its centre and the average radius of

    the earth trajectory. The power hits a circular disc with an area of of

    14 2 17 1.27 x 10 m . The power emitted to the earth is thus 1.74 x 10 W.

    2太阳发射至地球表面的功率密度为1.37 kW/m(这是以太阳为圆心(以地球轨

    142迹的平均半径计算的。发射功率投射到面积为1.27 x 10 m。因此(发射到地球上的功

    17率为1.74 x 10 W

    6 2) On average, plant net primary production is about 4.95 x 10 calories per

    square metre per year. This is global NPP, Global net primary production , i.e. the amount of energy available to all subsequent links in the food/energy chain.

    14 2 The earth's surface area is 5.09 x 10 m . The net power output stored by

    13 plants is thus 1.91 x 10 W, or 0.011% of the power emitted to earth. You may find the conversion factor between the energy units calories and Joule in the reference manual.

    6平均说来(植物的初始净产能(NPP)约为每平方米每年4.95 x 10 卡。这是全

    球的NPP,也就是以后可利用的食品/能源链的总量。地球表面积是于是5.09 x 10

    13 14 2m (植物所储存的净功率输出为1.91 x 10 W,或者为发射到地球上的功率

    0.011%。在参考手册中(你可以找到能量单位卡路里和焦耳的转换因子。

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The coriolis force 克里奥利力

    Since the globe is rotating, any movement on the Northern hemisphere is diverted to the right, if we look at it from our own position on the ground. (In the southern hemisphere it is bent to the left). This apparent bending force is known as the Coriolis force. (Named after the French mathematician Gustave Gaspard Coriolis 1792-1843).

    因为地球是旋转的(因此(从我们自己所在地球上的位置来看一个运动(北

    半球的任何运动都会向右偏移?在南半球它就会向左弯曲?。这种显而易见的弯

    曲力就称为克里奥利力。?在法国数学家古斯塔夫?盖斯帕德?克里奥利

    ?1792-1843?故去后命名的?

    It may not be obvious to you that a particle moving on the northern hemisphere will be bending towards the right.

    一个质点在北半球运动的时候会向右偏移(你看起来可能不明显。

    Consider this red cone moving southward in the direction of

    the tip of the cone. The earth is spinning, while we watch the

    spectacle from a camera fixed in outer space. The cone is

    moving straight towards the south.

    考虑一个红色的锥体(它的锥尖方向朝南运动。地球是旋

    转的(这是固定在外太空的照相机所观察到的景象。锥体直接朝南运动。

    Note that the red cone is veering in a curve towards the right as

    it moves. The reason why it is not following the direction in

    which the cone is pointing is, of course, that we as observers

    are rotating along with the globe

    注意到红色椎体当它运动的时候向右弯曲。为什么它不遵循锥体原来指定的

    方向(原因在于观察者随地球在旋转。

    Here we show the same image with the camera locked on

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to the globe.

    当照相机锁定在地球上的时候(我们会看到同样的图象。

    Here we show the same image,with the camera fixed in outer

    space, while the earth rotates.

    当照相机固定在外太空(而地球在旋转的时候(我们也会

    看到同样的图象。

    The Coriolis force is a visible phenomenon. Railroad tracks wear out faster on one side than the other. River beds are dug deeper on one side than the other. (Which side depends on which hemisphere we are in: In the Northern hemisphere moving particles are bent towards the right).

    克里奥利力是一种可视现象。铁轨的一侧比另一侧磨损快。河床的一侧比另

    一侧冲刷得深。?到底那一侧取决于我们所在的半球)在北半球运动质点向右偏?。

    In the Northern hemisphere the wind tends to rotate counterclockwise (as seen from above) as it approaches a low pressure area. In the Southern hemisphere the wind rotates clockwise around low pressure areas.

    在北半球(风倾向于逆时针旋转进入低压区域。在南半球(风倾向于顺时针

    旋转进入低压区域。

    On the next page we shall see how the Coriolis force affects the wind directions on the globe.

    下一节我们将看到克里奥利力如何影响全球风向的。

    Global winds 全球风

    风能资源全球风

    克里奥利力如何影响全球风向的

    The wind rises from the equator and moves north and south in the higher layers of the atmosphere.

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    风在赤道上升并在大气的高层向南北移动。

    Around 30?; latitude in both hemispheres the Coriolis

    force prevents the air from moving much farther. At

    this latitude there is a high pressure area, as the air

    begins sinking down again.

    在南北半球30?纬度处(克里奥利力对空气运动的

    阻力迅速增强(在这一纬度形成一个高压区域(空气开始沉降

    As the wind rises from the equator there will be a low pressure area close to ground level attracting winds from the North and South.

    因为赤道的风上升(在近地表面就形成了一个低压区域(这一区域将吸引南

    北方向的来风。

    At the Poles, there will be high pressure due to the cooling of the air.

    在极地(由于空气的冷却将形成冷高压。

    Keeping in mind the bending force of the Coriolis force, we thus have the following general results for the prevailing wind direction:

    记住克里奥利力的弯曲效应(对于主风向我们会导出下列的普遍结果)

    主风向

    Latitude 90-60?N 60-30?N 30-0?N 0-30?S 30-60?S 60-90?S 纬度

    Direction NE SW NE SE NW SE 风向

    The size of the atmosphere is grossly exaggerated in the picture above (which was made on a photograph from the NASA GOES-8 satellite). In reality the atmosphere is only 10 km thick, i.e. 1/1200 of the diameter of the globe. That part of the atmosphere is more accurately known as the troposphere. This is where all of our weather (and the greenhouse effect) occurs.The prevailing wind directions are important when siting wind turbines, since we obviously

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    want to place them in the areas with least obstacles from the prevailing wind directions. Local geography, however, may influence the general results in the

    table above, cf. the following pages.

    在上述图片中?由NASA GOES-8卫星拍摄的照片?(大气的尺度做了夸

    大。实际上大气只有10KM厚(即为地球直径的1/1200。那部分大气更精确地

    应称为对流层。这就是我们所说的天气以及温室效应所发生的地方。当风机选址

    时(主风向是非常重要的。因为我们显然希望把风机放在具有最少障碍物的主风

    向区域。但是(局部的地形可能影响上表中的普遍结果(请参阅下一节。

    Geostrophic wind 地转风

    地转风

    大气对流层

    The atmosphere around the globe is a very thin layer. The globe has a diameter of 12,000 km. The troposphere, which extends to about 11 km (36,000 ft.) altitude, is where all of our weather, and the greenhouse effect

    occurs.

    绕地球的大气是很薄的一层。地球直径为1200公里。对流层扩展到11

    里高处(这就是我们所说的天气以及温室效应所发生的地方。

    On the picture you can see a stretch of

    islands 300 km (200 miles) across,

    and the approximate height of the

    troposphere. To look at it at a different

    scale: If the globe were a ball with a

    diameter of 1.2 metres (4 ft.), the

    atmosphere would only be 1 mm

    (1/25") thick.

    在图片中你可以看到延伸300KM的岛屿以及同温层的近似高度。按不同的

    比例看它(如果地球是一个直径1.2m的球体(大气层只有1mm厚。

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