风力发电机组塔筒英文-汉语对照翻译

风力发电机组塔筒

高塔是水平轴风力机的必不可少的组成部分，事实上这既是一个优势也是一个劣势。成本将高达整体风力机成本的20%，这当然是不利的。同时塔高度的增加，对运输、装配和塔的安装及其原件的维修也变得日益困难和昂贵。另一方面，转子的能源产量也随着塔高的增加而提高。理论上，最佳的塔高是在建设成本和能源产量的交叉点。不幸的是，这个交叉点不能指定在任何形式上普遍适用。在大型的风力机中，随着塔高度的增加，建设成本比小型风力机增加要快。发挥更大作用的是选择地点。在内地的位置，即在表面粗糙度大的地区，与在岸基的位置相比，风速随高度增加风速增加缓慢。因此，更高的塔，会显示更好的回报比，例如，在海洋应用，会发现相反的效果。在内陆地区，大型风力发电塔的高度为80米，是一个经济使用风能潜力的决定性因素。

塔的第二个重要的设计参数是其刚度。建立第一自然弯曲频率的正确方法是一个重要的设计任务。这决定了所需要的材料和最终建设费用。塔的设计目标是在尽可能最低的建筑成本下实现理想的塔的高度和刚度要求。

运输和安装程序的发展成为最新一代的兆瓦级风机一个日益严重的问题。塔的高度超过100米和塔头重量几百吨需要一个在塔基五米以上的直径，其后果是公路运输将不再方便。这成为一个强大的激励寻求创新的解决塔设计的方案。

材料可用结构钢或混凝土。设计范围从拉索晶格结构或独立的钢管塔到大体积混凝土结构。整个系统可以通过转换满足技术要求，但几乎最佳经济只有通过适当的匹配选定塔设计的要求。这清楚表明，当只考虑塔本身时，虽然风机塔筒可以看作是一个传统结构，但它的设计还需要大量了解整个系统及其应用。

除了这些功能方面不应该忽视外，还要注重风机的外观。因此，预期的注意事项，应与美学一致，即使这意味着一些额外的费用。

1、塔式结构

古老的“风力”风车没有塔，但有磨房屋。这些低高度与转子直径有关，并且大量建设根据其功能作为一个工作空间，从而也提供了必要的机构刚度指标。但是，不久，高度增加的优势被认可，磨房变得更苗条，更像塔。但它是唯一的现代建筑，首先在美国小型风力机和随后在风力发电场的第一次发电，“桅杆”或“塔”的使用，唯一的功能是奠定了支承转子和机械部件的塔头。由于这种开发设计塔的材料

品种的增加。钢和混凝土代替了木结构的磨房.最初几年现代风能源技术的发展，大多不同的塔设计已尝试和测试，但在这过程中，范围已经缩小到独立的设计，主要是钢材和更为罕见的混凝土。

格构式

最简单的方法构建高刚性的塔结构是作一个三维桁架，所谓的格或桁架塔。因此，格塔，首选设计的第一个实验机和早期的风力机也为小商业所用。今天，在某些情况下，格塔再次成为内陆地区大型风力机中替代钢管塔的高塔。

混凝土类型

在30年代，钢筋混凝土塔进行所谓的“飞机发动机”在丹麦。这些塔也是特点较早的大型实验丹麦风力机，在丹麦，钢塔也成为占主导地位的商业风力机。混凝土塔最近获得高度超过80米的塔的青睐。

独立钢管塔

最常见的塔型目前使用的是独立的钢管塔。掌握振动状况，使它更容易使用，因此，非常低的设计刚度可以被实施。它已成为可能降低结构质量，降低成本，因此，大量使用“软”设计。

钢管塔结构

下风型转子有必要使用细钢管塔来保持尽可能小的塔影效应。这些塔被钢缆锚定或在某些情况下用刚性桁架确保所需的弯曲刚度。尽管较低的整体质量，桅杆还是很不划算。塔和附加锚固基础所需的总成本膨胀。此外，塔被认为是农业区的障碍。

2、独立的钢管塔

今天，独立的钢管塔是目前首选的建筑类型商业风力发电装置，主要原因在现场组装和建造时间短。小型塔高度高达20米可以在制造地组装成一件和在现场和地基连接在一起。更高的超过100米的塔是由几个部分固定在一起，而不必在现场焊接。对钢管塔的偏爱也受到过去20年钢材非常低的价格支撑。

（1）强度与刚度设计

塔的尺寸标注是由一系列的强度和刚度确定。要考虑的因素是断裂强度所需的极端风速，疲劳强度要求20或30年的运作和刚度方面的振动运行状况。

断裂强度

静载荷是由塔头重量，较低的自身重量，和气动转子推力组成。转子推力一般是在其最高水平时，转子运行在其额定速度，风机的叶片间距进行控制。最大弯矩分布在塔与转子叶片间距控制（无失速型风力机）或当最坏的转子叶片位置要求为特定的负载情况。在标准情况下，将降低断裂载荷作用在塔底时刻的问题。

疲劳载荷

动态负荷引起的转子推力在操作过程中对细长的塔疲劳寿命有一定的影响。额外负荷引起的振动也必须加以考虑。因此，一个纯粹的静态应力分析，常用的传统建筑的建筑主管部门的要求，并不适用于所有风力机的塔的设计。

弯曲强度

一个重要的标准，它发挥了作用，至少对低于1激发的薄壁钢管塔具有低自然弯曲频率，抵抗局部弯曲的管壁。作为一个现代钢管塔的增重优化的结果，弯曲强度，往往成为所需壁厚尺寸的决定因素。

塔刚度的特点是几个自然频率，但只有第一、二自然弯曲频率和第一扭转固有频率才具有实际意义。在大多数塔中，第一扭转固有频率远远高于第一自然弯曲频率. 如果其直径/壁厚比在正常范围，独立钢管塔的扭转频率高出约三倍。因此，它是充分利用第一自然弯曲频率获得一个粗略的概述。对于给定的塔的高度和重量，塔的设计必须以这样一种方式，达到所需的第一个自然弯曲频率。

刚性塔的设计始终是一个更简单和更安全的解决振动状况方面的方案，但大规模的塔来实现这一要求很难。因此，在风力机塔高度超过80米，刚性塔设计不可能再在实践中实现。经济方面的原因，其刚度应保持在低技术可行的基础上尽可能低。

（2）制造技术与施工

几乎没有例外，如今，大型风力机的塔有一个圆锥形，从地基到塔顶直径减少。与圆柱几何相比，对于一个给定的刚度要求，这样可以节省重量。

该塔由一个预制节长度可达约30米的部分，是由厚度10 - 50毫米的钢板制成。这些板材宽约2米，卷成圆形形状。从这些部分，塔部分被焊接在一起。在大多数情况下，自动焊接机被用于此。鉴于塔的承载情况，焊接需要被特别关注。

通常质量的检查的方法，如X射线和超声波检查表面裂纹。塔板材由商用st52等级结构钢板，很少用st48。高强度材料大多数用于法兰和基础部分的连接。

在两端各塔节，内部法兰被焊接。它们是由高强度钢和锻钢组成。成形和焊接法兰需要一些经验，因为组件很容易扭曲.后果是，法兰在装配时不匹配。由此产生的差距是一个质量缺陷，经常可以发现在钢管塔上。

作为一项规则，该塔是通过一个所谓的基础部分固定在一起。这是单独制造，并在浇筑时纳入基础混凝土。

该塔是机舱通过方位法兰连接。它可容纳的方位轴承使用滚子轴承。方位角法兰往往是铸造的一部分。

表面处理是关于钢管塔质量的一个重要部分。即便是在一个过度的环境（“海洋空气”）中，几十年内也必须阻止腐蚀。一些破坏后，塔节都覆盖着镀锌涂层。外涂层由至少两个，最多三个不同的油漆涂层。有些国家或地区法规规定塔的颜色。

制造一个直径达4米左右，高度超过90米，塔底直径大于4.5米和所需厚度超过40毫米的钢管塔是一种传统的技术，不会对任何设备厂家有所需求。塑造钢筒，即滚弯，然后需要特殊机器，它并不总是正常钢结构工程。也就是说，由于大直径，下塔节不再通过公路运输。

（3）攀登助手和内部安装

塔必须提供一个安全上升到到机舱的装置，也包含一定的电气安装，特别是在电力传输电缆引下到塔底。这需要一定的内部安装。根据不同的高度，通常安装一些中间平台，通常是一个塔节一个平台。用于攀登高度约60-70米简单的垂直梯攀登保护。如果工作需要，塔高超过80米，可安装简单的所谓“登山电梯”。

对于某些应用和内部的设备，即变压和控制系统，塔的内部气候必须被控制。特别是海上应用，空调可以除湿，过滤进气是必要的，以避免对电气和电子设备腐蚀问题。

小型风力发电机组塔施工简单得多。高度约为15米的塔，塔是从外面爬。在一些国家，特殊劳动保护和保险业的要求，必须遵守关于外部提升的相关规定，以至于即使相对小的发电机，也提供一个安全的内部提升。

3、基础

塔基的大小是由风力机和局部场地条件决定的。在这方面，必须考虑最高的荷载作用下的风力机停滞条件。这里决定因素是最高的假定风速，所谓的生存风速。然而，风机的技术概念也起到了一定的作用。轮机失速控制不仅提供羽状叶片，而

且用这样的设计可发生较高的停滞荷载作用，这对标注的基础和成本上具有重要意义。

负荷的情况下，在最高负荷状况必须检查.在运行中，最大倾斜的时刻为基础由转动推力决定.可控转子叶片推力的风力机在额定功率达到其高峰期，而在失速型风力机，尽管滞后的功率已达到，它会继续增加。

被官方要求的设计审批和安全认证在大多数情况下是基于这些静载荷。考虑到动态载荷疲劳寿命的计算通常不要求。这些计算是制造商的责任。

根据不同的地质条件，要求是板式基础或桩基础.决定性因素是埋在将吸收施加载荷的土壤层的深度。

板式基础

板式基础，通常被称为标准的基础，为圆形或矩形多边形基脚。钢管塔扎根的一个基础部分加入到钢筋混凝土中。要求的质量和直径的板是由倾覆的结构决定的。这是依靠风力机，塔，基础本身抵抗的。离心铸造预制混凝土塔是“投”到基础的。

桩基础

薄弱土壤的桩基础有放在一堆的木板，可将负荷转移到承重地面层上。为此使用预制“羊桩”。桩基础是必要的。例如，在德国北海附近沿海沼泽地区，在这些地区，固沙层的大陆架在一些情况下位于深达20到25米。一个桩高达20米中型风力机，需要有相应的长度，保证承载能力，增加了基础成本的30%到50%。

作为一项规则，根据德国的分类，其所在公司的风力机基础由B类水泥构成。这是常见的做法，一个模架建立在基坑内，并且在混凝土浇入坑之前进行钢筋编织。

整合与底部法兰连接基础的部分，而需要一些经验。法兰的基础部分必须放置在水平并且水平位置只有一个很小的公差来防止斜塔倾斜。在建立基础部分法兰直径大约3.6米的一个500千瓦风力机，最大允许偏差的水平范围在2毫米。

很明显，在地面上，土壤的一致性或更准确地说，塔的“夹紧刚度”对自然弯曲频率有一定影响。然而对于非常松散的土壤，这并不适用于每一种情况。

The tower

The high tower is an essential component of the horizontal-axis turbine, a fact which can be both an advantage and a disadvantage. The costs, which can amount to up to 20 % of the overall turbine costs, are, of course, disadvantageous. As the height of the tower increases, transportation, assembly and erection of the tower and servicing of the components also become increasingly more difficult and costly On the other hand, the specific energy yield of the rotor also increases with tower height. Theoretically, the optimum tower height lies at the point where the two growth functions of construction cost and energy yield intersect. Unfortunately, this point of intersection cannot be specified in any generally applicable form. In larger turbines, construction costs rise more rapidly with increasing tower height than in small turbines. An even greater role is played by the choice of site. At inland sites, in regions with a high degree of surface roughness, the wind speed increases more slowly with height than at shore-based sites. Higher towers will, therefore, show better returns here than, for example, in offshore applications where the reverse effect is found. In inland regions, large wind turbines with tower heights of 80 m and more are a decisive factor for the economic use of the wind potential.

Next to its height, the second most important design parameter of a tower is its stiffness. Establishing the first natural bending frequency in the right way is an important task in the design. This determines the material required and, ultimately, the construction costs. The goal of the tower design is to achieve the desired tower height with the required stiffness at the lowest possible construction cost.

The transportation and the erection procedure is developing; into an increasing problem for the latest generation of multi-megawatt wind turbines. Tower heights of more than 100m and tower head weights of several hundred tons require a diameter at the tower base on more than five meters, with the consequence that road transportation will

no longer be leasable. This becomes a strong incentive to find innovative solutions in the tower design.

The materials available for the construction are steel or concrete. Designs range from lattice construction to guyed or free-standing steel tubular towers up to massive concrete structure. The technical requirements posed by the overall system can be met by almost my variant but the economic optimum is only achieved by appropriately matching the selected tower design to the requirements set. This shows clearly that, although the tower of a wind turbine can be seen as a conventional structure when considered by itself, its design also requires a considerable amount of understanding of the overall system and its application.

Apart from these functional aspects, it should not be overlooked that the tower, even more so than the nacelle, determines the outward appearance of a wind turbine. Due attention should, therefore, be accorded aesthetics, even if this implies some additional costs.

1.Tower configurations

The oldest types of "wind turbines", the windmills, had no towers but millhouses. These were low in height in relation to the rotor diameter and of voluminous construction in accordance with their function as a work space, thus also providing for the necessary stiffness. Soon, however, the advantage of increased height was recognized and the millhouses became more slender and more tower-like. But it is only in modern-day constructions, first in the small American wind turbines and then later in the first power-generating wind power stations, that "masts" or "towers" were used, the sole function of which lay in supporting the rotor and the mechanical components of the tower head. As a consequence of this development, designs and materials for towers increased in variety. Steel and concrete took the place of the wood construction of the millhouses. In the early years of the development of modern wind energy technology, the most varied tower designs were tried out and tested but in the course of time, the range

has been narrowed down to free-standing designs, mainly of steel and more rarely of concrete.

Lattice Type

The simplest method of building high and stiff tower constructions is as a three-dimensional truss, so-called lattice or truss towers. Lattice towers were, therefore, the preferred design of the first experimental turbines and in the early years also for smaller commercial turbines. Today, the lattice tower has again become an alternative to the steel tubular tower in the case of the very high towers required for large turbines sited in inland regions.

Concrete Type

In the thirties, steel-reinforced concrete towers were used for the so-called "Aeromotor" in Denmark. These towers were also characteristic of the earlier large experimental Danish turbines Later, steel towers became dominant also in the commercial turbines in Denmark. Concrete towers have recently gained favor again for tower height of more than 80m.

Free-standing steel tubular towers

the most common tower type currently in use is the free-standing steel tube tower. Mastery of the vibrational behavior has made it easier to use this type so that steel tubular towers with very low design stiffness can be implemented. It has thus become possible to lower the structural mass, and thus the costs of the towers, considerably by using "soft" designs.

Guyed steel tubular towers

Down-wind rotors made it necessary to use slender steel tubular towers in order to keep the tower shadow effect as small as possible. These were anchored with steel cables or in some cases with stiff trusses to ensure the required bending stiffness. Despite their comparatively low overall mass, guyed towers are not very cost-efficient. The guys and the additional anchoring foundations required inflate the total cost. Moreover, the guys

are considered a hindrance in agricultural areas.

2.Free-Standing Steel Tubular Towers

Today, free-standing steel tubular towers are by far the preferred type of construction for commercial wind turbine installations, the main reason being the short on-site assembly and erection time. Small towers with a height of up to 20m can be fabricaled of one piece at the manufacturer's and bolted to the Foundation at the site. Higher towers of up to 100m height are made of several sections which are bolted together so that no on-site welding is required. The preference for steel tubular towers is also buoyed by the very low steel prices in the last twenty years.

（1）Strength and Stiffness Design

The dimensioning of a tower is determined by a number of strength and stiffness requirements. Factors to be considered are the breaking strength required for surviving extreme wind speeds, the fatigue strength required for 20 or 30 years of operation and the stiffness with respect to the vibrational behavior.

Breaking Strength

The static load is determined by the tower-head weight, the lower's own weight, and the aerodynamic rotor thrust. In turbines with blade pitch control, rotor thrust is generally at its highest level when the rotor is running at its rated speeds. The maximum bending moment distribution at the tower is obtained with rotors without blade pitch control(stall-controlled turbines) or when the worst rotor blade position is demanded for a particular load case. In the standard case, the question of breaking load will be reduced to that of the bending moment acting on the tower base.

Fatigue loading

The dynamic loading caused by the rotor thrust during operation has a definite impact on the fatigue life of slender tower. Additional loads caused by the vibrational behavior in cases of resonance must also be taken into consideration. Hence a purely static stress

analysis, commonly required by the building authorities for conventional buildings, is not appropriate for all tower designs of a wind turbine.

Buckling strength

One important criterion which plays a role at least for thin-walled steel tubular towers with a low natural bending frequency below the 1 P excitation is the resistance to local buckling of the tube wall. As a result of the increasing weight optimization in modern steel tubular tower, the buckling strength frequently becomes the determining dimensioning factor for the required wall thicknesses.

Tower stiffness is characterized by several natural frequencies, but only the first and the second natural bending frequency and the first natural torsion frequency are of any practical significance. In most towers, the first natural torsion frequency is much higher than the first natural bending frequency. the torsion frequency of free-standing steel tubular towers is approximately three times higher if their diameter/wall thickness ratio lies within normal limits. It is, therefore, sufficient to use the first natural bending frequency for obtaining a rough overview. With a given tower height and head weight, the tower must be designed in such a way that the required first natural bending frequency is reached.

A stiff tower design is always a simpler and safer solution with regard to vibration behavior, but the mass of the tower required to achieve this becomes very high. In wind turbines with tower heights of more than 80m,a stiff tower design can, therefore, no longer be realized in practice. For economic reasons, the stiffness should be kept as low as technically feasible.

（2）Manufacturing Techniques and Construction

Almost without exception, the tower of the large turbines of today have a conical shape, with a diameter that diminishes from the base up to the tower head. Compared with a cylindrical geometry, this saves weight for a given required stiffness.

The towers consist of a number of prefabricated sections with a length of up to about 30m. The sections are produced from sheets of steel plate with a thickness of 10-50 mm. The sheets, which have a width of about 2 m, are rolled into a circular shape on a rolling stand. From these segments, the tower section is welded together. In most cases, automatic welders are used for this. The welding requires special attention in view of the loading situation of the tower. The quality is checked by means of the usual methods such as ultrasonic, X-rays and examination for surface cracks. the tower sheets consist of commercially available St52 grade structural steel plate and, more rarely St48. Higher-strength material is used for most of the forged joining flanges and the foundation section.

At the ends of each tower section, the internal flanges are welded on. They consist of high-strength steel and occasionally of forged steel. Shaping and welding of flanges requires some experience since the components can easily become distorted. the consequence being that the flanges will not match during the assembly. The resultant gaps between the tower sections are a quality defect frequently found in steel tubular tower.

As a rule, the tower is joined to the foundation by means of a so-called foundation section. This is manufactured separately and incorporated in the foundation when the concrete is poured.

The tower is joined to the nacelle via the azimuth flange. It accommodates the azimuth bearing if a roller bearing is used. The azimuth flange is often a cast part.

Surface treatment is an important feature regarding the quality of steel towers. Corrosion must be prevented over decades even in an aggressive environment ("sea air"). After some blasting, the tower section are covered with thermally applied zinc coating. The outer coating consists of at least two and at most three different paint coats. Some countries or regions have regulations regarding the color of the tower.

Manufacturing steel tubular towers with a diameter of up to about 4m is a

conventional technology that does not make any great demands on the equipment of the manufacturers. At heights of more than 90m, the tower base diameter becomes greater than 4.5m and the required thickness of the steel exceeds 40 mm. Shaping the Steel ,i.e. roll-bending them, will then require special machines which are not always available in normal structural steel works. To this is added that, due to the large diameter, the lower tower sections can no longer be transported by road.

（3）Climbing Aids and Internal Installation

The tower must provide for a safe ascent to the nacelle and also contain certain electrical installation, particularly the lead-down of the power transmission cables to the tower base. This requires certain internal installation. Depending on the height, a number of intermediate platforms are normally installed, typically one platform for each tower section .Up to a height of about 60-70m simple vertical ladders with climbing protection are used for the ascent. If required by the operator, simple so-called "climbing lifts" are installed for tower heights above 80m.

For some applications and depending on the internal equipment, i. e. transformers and control systems, the internal climate of the tower has to be controlled. Particularly for offshore applications, air conditioning including dehumidifying and filtering the intake air is necessary in order to avoid corrosion problem on the electrical and electronic equipment.

The towers of small wind turbines are of much simpler construction. In some case, existing tubular elements from other applications can be used for the manufacture. Up to tower heights of about 15m,the tower is climbed from the outside. In some countries, special work protection rules and insurance requirements must be observed with respect to an external ascent so that there is a trend to provide a safe internal ascent even in relatively small turbines.

3.The Foundation

The foundation of the tower is determined by the size of the wind turbine and by local ground conditions. In this respect, it is primarily, the highest loads acting on the wind turbine under stand-still conditions which must be considered. The determining factor is here the highest assumed wind speed, the so-called survival wind speed. However, the technical concept of the wind turbine also plays a certain role. Turbines with stall control do not provide the option of feathering the rotor blades so that comparatively high stand-still loads can occur with this design, a fact which is of significance in the dimensioning of the foundation and thus in the costing.

A second load case, which must at least be checked, is that involving the highest loads during operation. In operation, the maximum tilting moment for the foundation is deter-med by rotor thrust. In turbines with blade pitch control rotor thrust reaches its peak at the rated power, whereas in stall-controlled turbines it continues to increase even after the late power has been reached.

The design approval and safety certification required by the authorities is in most cases based on these static loads. Fatigue life calculations taking into consideration the dynamic load spectrum are normally not requested. Those calculations are carried out under responsibility of the manufacturer.

Depending on the geological conditions, either slab foundation or pile foundations are required. the decisive factor is the depth at which soil layers are found which will absorb the loads imposed.

Slab Foundations

The slab foundation, often called the standard foundation, are circular or rectangular of polygonal footings. The steel tubular towers are anchored by a foundation section joined to the steel reinforcement of the concrete. The required mass and the dimension of the slab are determined by the overturning moment of the structure. This is resisted by the weight of the turbine, the tower and the foundation itself. Centrifugally cast prefabricated

concrete tower are "cast" into the foundation.

pile foundations

Pile foundations for weak soils have a bed plate sitting on pile which transfer the loads into load-bearing ground layers. For this purpose prefabricate" ram piles" are used. pile foundations are necessary, for example ,in the German coastal marshland areas near the North Sea. In these areas ,the solid sand layers of the continental shelf are in some case located at a depth of 20 to 25m.The pile, up to 20 of which are required for a medium sized turbine ,are of corresponding length to ensure the load-carrying capability of the foundation, This increases the cost of the foundation by 30% to 50%.

As a rule, the foundations of wind turbines are constructed of Category B 25 concrete according to the German classification. As is common practice, a formwork is set up in the foundation pit and the steel reinforcement is plaited before the concrete is poured into the pit.

Integrating the foundation section, to which the bottom flange of the tower is joined requires some experience. The flange of the foundation section must be placed in a horizontal and level position with only a small tolerance to prevent the tower from slanting. In the foundation of a wind turbine of the 500KW class with an foundation section flange diameter of approximately 3.6m, the maximum allowable deviation from the horizontal in the range of 2mm.

It is obvious that the soil consistency or, more precisely, the "clamped stiffness" of the tower in the ground, has an influence on the natural bending frequency. In very loose soil, however, this does not apply in every case.