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Effects of Flexibility and Suspension Configuration of Main Shaft on Dynamic Characteristics of Wind Turbine Drivetrain

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 224-238页

作者： Jianjun Tan Caichao Zhu Chaosheng Song huali han Yao Li The State Key Laboratory of Mechanical Transmissions Chongqing University CSIC (Chongqing) Haizhuang Windpower Equipment Co. Ltd

The current research of wind turbine drivetrain is mainly concentrated in dynamic characteristics of gearbox with a specific suspension of main shaft, such as one-point and two-point suspension. However, little attention is paid to the e ects of these suspension configurations on the dynamic responses of wind turbine gearbox. This paper investigates the influences of suspension configurations of main shaft on the dynamic characteristics of drivetrain. For evaluating the dynamic behaviors of drivetrain with multi-stage transmission system more realistically, a dynamic modeling approach of drivetrain is proposed based on Timoshenko beam theory and Lagrange's equation. Considering the flexibility and di erent suspension configurations of main shaft, time-varying mesh sti ness excitation, time-varying transmission error excitation and gravity excitation, etc., a three-dimensional dynamic model of drivetrain is developed, and the dynamic responses of drivetrain are investigated. Results show that with the one-point suspension of main shaft, the resonance frequencies in gearbox, especially at the low-speed stage, obviously shift to the higher frequency range compared to the gearbox without main shaft, but this trend could be inversed by increasing main shaft length. Meanwhile, the loads in main shaft, main shaft bearing and carrier bearing are greatly sensitive to the main shaft length. Hence, the load sharing is further disrupted by main shaft, but this e ect could be alleviated by larger load torque. Comparing to the one-point suspension of main shaft, there occurs the obvious load reduction at the low-speed stage with two-point suspension of main shaft. However, those advantages greatly depend on the distance between two main bearings, and come at the expense of increased load in upwind main shaft unit and the corresponding main bearing. Finally, a wind field test is conducted to verify the proposed drivetrain model. This study develops a numerical model of drivetrain

关键词： Wind turbine drivetrain Flexible shafts Suspension configuration Dynamic responses Experimental study

Soil Erosion Control Degree of the Project of Converting Farmland to Forest in Mountainous Areas at China's Southwest Border:A Case Study in Mangshi,Yunnan Province

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Journal of Mountain Science 2011年第6期8卷 845-854页

作者： YANG Zisheng han huali ZHAO Qiaogui Institute of Land ＆ Resources and Sustainable Development Yunnan University of Finance and Economics Kunming 650221 China Southwest University Chongqing 400715 China Department of Land ＆ Resources of Yunnan Province Kunming 650224 China

There have been few in-depth quantitative studies on soil erosion control and the ecological effects of land use changes. Soil erosion is the first eco-environmental problem particularly in mountainous areas. A major problem in the conversion of farmland to forest is to control soil erosion and improve ecological environment and thus to improve land use sustainability. We report results of calculation and analysis on soil erosion from converted farmland parcels in city of Mangshi （near the SW frontier of China） and the surrounding areas before and after the nine-year （2000-2009） project of converting farmland to forest. There was increased water conservation effect, as a result of decreased soil erosion. The average erosion modulus of the farmland returning to eco-friendly uses decreased by 5,535.59 t/km2·a and the control degree of soil erosion modulus reached 71.00%. The increased soil erosion after the returning in the typical sample area ＂did not drop, but increased＂ as the terraced fields decreased but sloping farmland inereased and yet woodland decreased.

关键词： Soil erosion Control degree The projectof converting farmland to forest Converted farmland

Quality and efficiency improvement technology for five megawatt offshore wind turbines and its application

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Frontiers of Engineering Management 2020年第4期7卷 618-621页

作者： huali han Yalin LIU Can WANG Research Institute of China Shipbuilding Group Haizhuang Wind Power Co. Ltd.Chongqing 401122China

1 Background The offshore wind resources of China are widely distributed and have large regional *** Yellow Sea and Bohai Sea areas,which account for 60%of the developable sea area,have an annual average wind speed of less than 7.5 m/s(Xu et al.,2013).According to the current level of offshore wind power transportation,construction,and operation and maintenance,the profit balance point of 5.0 MW offshore wind turbines is 3000 h/year(Zheng,2017).However,in the Yellow Sea and Bohai Sea areas,even if the world’s best offshore wind turbines at that time are used,their full power generation hours can only reach approximately 2900 h/*** phenomenon is on the verge of profitability or loss,resulting in a large number of sea areas,especially the Bohai Sea area,with no development ***,developing offshore wind turbines with strong power generation capacity and low cost,which is suitable for the sea areas in China,is urgently ***,the H1715.0 MW offshore wind turbine project is introduced.

关键词： renewable energy megawatt offshore wind turbine technology-driven quality improvement

湍流强度对风电机组测量功率曲线的影响及修正

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太阳能学报 2015年第6期36卷 1442-1447页

作者：韩花丽张根保杨微重庆大学机械工程学院重庆400044 中船重工(重庆)海装风电设备有限公司重庆401122

通过分析湍流强度对风电机组输出功率统计曲线的影响,提出风电机组输出功率统计曲线的湍流强度修正方法。与按IEC标准对测试机组数据统计方法所得的结果相比,采用该文所提出的修正方法比标准统计方法所得结果的不确定度更低,可更准确反... 详细信息

通过分析湍流强度对风电机组输出功率统计曲线的影响,提出风电机组输出功率统计曲线的湍流强度修正方法。与按IEC标准对测试机组数据统计方法所得的结果相比,采用该文所提出的修正方法比标准统计方法所得结果的不确定度更低,可更准确反映机组实际运行状态,为机组的正常维护、运行优化及风电场建设前期发电量估算提供可靠的依据。

关键词：湍流强度风电机组测量功率曲线修正方法

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医学院校护理人才订单培养模式的研究与实践

中国卫生事业管理 2010年第1期27卷 67-68页

作者：韩华丽川北医学院附属医院四川南充637007

订单培养是近年来医学院校和用人单位合作培养护理人才的一种新模式。文章结合与地方医院培养护理人才的实践与经验,就医学院校如何进行护理人才订单培养,提高护理教学质量,促进学生就业进行了探讨。

关键词：订单培养护理人才就业

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大型风电机组地震载荷计算方法优化

太阳能学报 2014年第11期35卷 2294-2299页

作者：韩花丽张根保杨妍妮董晔弘重庆大学机械工程学院重庆400044 中船重工(重庆)海装风电设备有限公司重庆401122

通过对比传统建筑物与风电机组的特性差异,提出需要考虑风电机组特性的模态振型分析方法及结合风电机组受载特性,修正地震效应的叠加方法。基于此方法对某2.0 MW风电机组进行地震载荷动力学分析,分析数据同风电机组权威软件GH Bladed 4.... 详细信息

通过对比传统建筑物与风电机组的特性差异,提出需要考虑风电机组特性的模态振型分析方法及结合风电机组受载特性,修正地震效应的叠加方法。基于此方法对某2.0 MW风电机组进行地震载荷动力学分析,分析数据同风电机组权威软件GH Bladed 4.2数据比较表明,该分析方法可较好地计算风电机组的地震载荷,从而可为简化地震载荷计算流程提供有力技术支撑。

关键词：风电机组地震振型分解法 GH Bladed

水平轴风力机主轴与轮毂联接螺栓数值分析研究

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太阳能学报 2016年第7期37卷 1702-1710页

作者：杜静唐与韩花丽周云鹏龚国伟重庆大学机械工程学院重庆400044

针对水平轴风力发电机轮毂与主轴法兰连接处螺栓所受极限载荷问题,基于VDI 2230螺栓连接准则,提出等效梁法,并以此建立螺栓轴向及径向刚度数学模型,重点对螺栓连接的螺纹啮合区进行理论分析,计算螺纹受力以及实际工况下螺栓的等效应力... 详细信息

针对水平轴风力发电机轮毂与主轴法兰连接处螺栓所受极限载荷问题,基于VDI 2230螺栓连接准则,提出等效梁法,并以此建立螺栓轴向及径向刚度数学模型,重点对螺栓连接的螺纹啮合区进行理论分析,计算螺纹受力以及实际工况下螺栓的等效应力。采用有限元理论对MW级风力机法兰连接处螺栓在ANSYS中进行强度分析,有限元结果与理论分析结果基本一致。研究为螺栓连接强度分析提供了新思路。

关键词：风力机连接螺栓 VDI 2230准则等效梁法强度分析

小型失速型风力发电机实验测试及最大功率跟踪控制研究

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现代制造工程 2012年第6期 9-13页

作者：张晓峰金鑫韩花丽重庆广播电视大学重庆400052 重庆大学机械学院重庆400044

以9台轴流式风机作为源动力,构建开放式风洞测试实验平台,用变频器调节风机转速以产生需要的模拟风速。通过测量风速值,以及1kW小型失速型风力发电机的输出电压和电流,经过数据采集卡,传送到工控机。为达到功率优化吸收,进行了系统硬件... 详细信息

以9台轴流式风机作为源动力,构建开放式风洞测试实验平台,用变频器调节风机转速以产生需要的模拟风速。通过测量风速值,以及1kW小型失速型风力发电机的输出电压和电流,经过数据采集卡,传送到工控机。为达到功率优化吸收,进行了系统硬件电路设计,通过控制计数器输出脉宽调制(PWM)脉冲来控制并优化小型失速型风力发电机的功率。开发的实验测试系统对小型失速型风力发电系统的研究具有重要意义。

关键词：风力发电测试系统实验系统功率跟踪控制

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兰州百合的组织培养

天津师范大学学报（自然科学版） 2009年第3期29卷 62-65页

作者：韩华丽郭成金天津师范大学化学与生命科学学院天津300387

以兰州百合鳞片作为外植体进行组织培养,分别对其进行芽诱导、增殖、生根培养,得到了兰州百合鳞片组织培养的最佳培养基配方:⑴芽诱导培养基:MS+BA 0.6 mg/L+NAA 0.2 mg/L+琼脂7.3 g/L+蔗糖30 g/L,pH 5.8;⑵增殖培养基:MS+BA 0.8 mg/L+N... 详细信息

以兰州百合鳞片作为外植体进行组织培养,分别对其进行芽诱导、增殖、生根培养,得到了兰州百合鳞片组织培养的最佳培养基配方:⑴芽诱导培养基:MS+BA 0.6 mg/L+NAA 0.2 mg/L+琼脂7.3 g/L+蔗糖30 g/L,pH 5.8;⑵增殖培养基:MS+BA 0.8 mg/L+NAA 0.05 mg/L+琼脂7.3 g/L+蔗糖30 g/L,pH 5.8;⑶生根培养基:MS+BA 0.05 mg/L+NAA 0.8 mg/L+琼脂7.3 g/L+蔗糖30 g/L,pH 5.8.观察与分析结果表明,外植体在前两种培养基上的繁殖速率较前人快约15 d,第3种培养基与前人的相当,比其快2 d.

关键词：兰州百合鳞片组织培养