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为了使风力发电机组偏航系统驱动电机的选型准确合理,也为了揭示偏航电机在超过截断值外载后的运行情况,文章提出了一种基于偏航电机特性(扭矩-转速)曲线和外载时间序列的仿真模拟方法,并用该方法定量地分析了3类工况下普通型和高海拔型两款偏航电机的运行情况。3类工况如下:(1)在额定转速下,偏航电机经历大于截断值外载,且逆风偏航;(2)偏航电机由静止开始启动时,经历大于截断值外载,且逆风偏航;(3)在额定转速下,偏航电机经历大于截断值外载,且顺风偏航。研究结果表明,在某些工况下,所选两款偏航电机会出现短时间的堵转运行或反拖运行问题。文章所提出的仿真方法,可为偏航电机的精细化选型提供定量参考,也可作为检验截断值外载是否合适的评判方法。 相似文献
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为研究复合材料输电塔架结构的受力性能,对330 kV复合材料输电塔架结构进行了有限元分析,考察了复合材料输电杆塔结构在不同工况下的位移和内力变化情况。研究结果表明:位移控制需要综合考虑断线和大风工况的影响,断线工况对复合材料内力的影响要大于其他工况,杆塔总弯矩值较小,塔体以受压为主,内力均匀分布,说明塔身斜度设计合理;杆件的最大应力发生在塔体底部,约200 MPa,塔体复合材料主材不到100 MPa,有较大的安全富裕度,塔体应力满足要求。 相似文献
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高耸的风力机塔架结构属于典型的顶部附有大集中质量的细长柔性体的力学结构,相比传统建筑结构差异性较大,极易受到地震载荷影响。基于有限元分析软件ABAQUS建立风力机塔架、基础平台和土体模型,通过FAST导出风轮非定常推力,作用在塔顶机舱,土体底部施加地震加速度时间序列,进行风力机结构模态分析、稳定性分析和动力学响应分析。研究表明:塔架主要的运动形式为摇摆运动和弯曲振动;塔架一阶固有频率为0.290 Hz,大于风轮的额定旋转频率0.202 Hz,因此叶片旋转不会引起风力机塔架发生共振;风载荷作用下,塔架发生横向屈曲,屈曲位置位于塔架底部且随模态阶数增大而逐渐向上发展,屈曲因子较大;地震载荷作用下,塔架发生纵向屈曲,屈曲位置同样位于塔架底部且随模态阶数增大而逐渐向上发展,较风载荷发生屈曲区域相对更大,屈曲因子相对较小。 相似文献
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离心式风机叶轮前盘外沿在运行中发生局部损坏脱落,在国内外是很少发生的。对发生在2002年以来上海石化热电总厂CFB锅炉一次风机叶轮损坏的情况作了介绍,对损坏的前盘断口情况作了描述,分析了损坏原因,介绍了处理情况。比较了CFB锅炉风机与四角燃烧煤粉炉风机的不同之处,总结了CFB锅炉一次风机的选型技术要求,供有关人员借鉴。 相似文献
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侯兴仁 《电网与水力发电进展》1992,(4)
水轮发电机由干电力系统种种原因.运行中突然甩掉全负荷的情况是比较多的.甩负荷后调速器失控引起发电机组转速升高造成机械破坏.特别是转速较高的发电机线速度高,要求过速保护要非常可靠,也就是转速继电器要可靠.为了动作可靠.一般过速转速信号来自永磁机副绕组电压.此电压与发电机转速成正比关系.另一路与同轴离心式转速继电器的接点并联.如图1所示.这样在出现过速的情况下,电气接 相似文献
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对XE82直驱型风机的整体运行情况作了简要介绍,描述了XE82直驱型风机的偏航系统组成、作用及控制过程.通过数据分析发现XE82直驱型风机的偏航系统在高风速下运行时存在的一些问题并给出解决方案. 相似文献
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风力发电机组的主要部分由风力机和发电机所组成。为了尽可能的尊重实际风力机的物理特性及其运行的物理过程,需要分清控制对象并将风力机与发电机相分离,对其进行独立研究。并通过分析风力发电机组的额定工作点,将额定风速以上的桨叶节距角控制转化为风力机额定转速以上的桨叶节距角控制,最终经实验证实仿真方法实用性与正确性。 相似文献
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针对山地风电场大型永磁同步风电机组发电机定子温度的变化特点及传热过程进行分析,提出一种基于风电机组SCADA数据的发电机定子温度建模方法。首先,分析风电机组在实际运行过程中定子温度的变化情况;然后,根据永磁同步发电机内部的传热过程,对发电机定子温度建模;最后,采用风电机组正常运行时的SCADA数据求解模型参数。实例分析表明,风电机组状态正常时,定子温度估计的平均误差绝对值为0.59 ℃,模型精度较高;风电机组状态异常时,模型温度估计的平均误差绝对值为5.17 ℃,精度显著降低。 相似文献
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Tetsuya Wakui Kazuya Yamaguchi Takumi Hashizume Eisuke Outa Yoshiaki Tanzawa 《Renewable Energy》1999,16(1-4)
The effect of how a wind turbine generator system is operated is discussed from the viewpoint of net power extraction with wind velocity fluctuations in relation to the scale and the dynamic behavior of the system. On a wind turbine generator system consisting of a Darrieus-Savonius hybrid wind turbine, a load generator and a battery, we took up two operating methods: constant tip speed ratio operation for a stand-alone system(Scheme1) and synchronous operation by connecting a grid(Scheme2). With our simulation model, using the result of the net extracting power, we clarified that Scheme1 is more effective than Scheme2 for small-scale systems. Furthermore, in Scheme1, the appropriate rated power output of the system under each wind condition can be confirmed. 相似文献
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Grid connected wind turbines may produce flicker during continuous operation. This paper presents a simulation model of a MW-level variable speed wind turbine with a doubly fed induction generator developed in the simulation tool of PSCAD/EMTDC. Flicker emission of variable speed wind turbines with doubly fed induction generators is investigated during continuous operation, and the dependence of flicker emission on mean wind speed, wind turbulence intensity, short circuit capacity of grid and grid impedance angle are analyzed. A comparison is done with the fixed speed wind turbine, which leads to a conclusion that the factors mentioned above have different influences on flicker emission compared with that in the case of the fixed speed wind turbine. Flicker mitigation is realized by output reactive power control of the variable speed wind turbine with doubly fed induction generator. Simulation results show the wind turbine output reactive power control provides an effective means for flicker mitigation regardless of mean wind speed, turbulence intensity and short circuit capacity ratio. 相似文献
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This article compares three reduced models with a detailed model of a doubly fed induction generator system for wind turbine applications. The comparisons are based on simulations only. The main idea is to provide reduced generator models which are appropriate to simulate normal wind turbine operation in aeroelastic wind turbine models, e.g. for control system design or structural design of the wind turbine. The electrical behaviour such as grid influence will therefore not be considered. The work presented in this article shows that with an ideal, undisturbed grid the dynamics of the doubly fed induction generator system is very well represented by the dynamics due to the generator inertia and the generator control system, whereas the electromagnetic characteristics of the generator can be represented by the steady state relations. The parameters for the proposed models are derived from parameters typically available from the generator data sheet and from the controller settings. Thus the models are simple to apply in any case where the generator data sheet is available. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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Power converters play a vital role in the integration of wind power into the electrical grid. Variable-speed wind turbine generator systems have a considerable interest of application for grid connection at constant frequency. In this paper, comprehensive simulation studies are carried out with three power converter topologies: matrix, two-level and multilevel. A fractional-order control strategy is studied for the variable-speed operation of wind turbine generator systems. The studies are in order to compare power converter topologies and control strategies. The studies reveal that the multilevel converter and the proposed fractional-order control strategy enable an improvement in the power quality, in comparison with the other power converters using a classical integer-order control strategy. 相似文献