Underactuated control and analysis of single blade installation using a jackup installation vessel and active tugger line force control

The assembly and installation costs account for a large share in the overall expenditures of an offshore wind farm project. Single blade installation is suitable for large scale wind turbines due to the lower crane capability requirement and lower transportation time. By introducing active tension control on the tugger lines, an automatic single blade installation approach can accomplish operations in higher sea states, reduce the waiting-on-weather time, and improve the operational efficiency. Compared to early research, a more complicated control objective is achieved in this paper, i.e., a two-tugger-line configuration is applied to stabilize the suspended blade in three degrees of freedom during crane rotation and blade root-hub mating processes. The pulleys on the crane boom, i.e., the ends of the tugger lines, are assumed to be fixedly placed, resulting in tugger line time-varying inclinations. A novel backstepping-like controller is designed and proved. It is able to stabilize the blade around its equilibrium and make it track the desired path. Sensitivity studies are conducted to evaluate the influence of the tugger line inclinations. In addition, the influence of the installed blades on a three-blade horizontal wind turbine with a monopile foundation is discussed. The proposed active control setup improves the installation success rate and reduces the risks for blade impacts that may occur during mating.     

压力流玻璃钢夹砂管在顶管施工中的应用与分析

该文分析了压力流玻璃钢夹砂管及其顶管工程施工工艺的优点,介绍了上海市富长路试验段以此工艺施工的过程,并对施工过程中出现的问题进行了总结和分析。     

水利工程中的泵房施工技术重难点分析

为保证泵房工程施工质量,专业的施工方案及技术水平是关键.通过对一般泵房施工方案的总结分析,将其施工分为基础结构、主体、砌筑粉刷三个阶段,并分别分析了各个阶段的施工技术重难点,提出模板工程、钢筋工程、混凝土工程中相应的施工工艺及质量控制要点,总结相关设计参数的控制指标,为类似工程提供参考.     

船用脱硫装置特种不锈钢管焊接工艺设计

通过研究船用脱硫装置设计及材料特性,结合项目产品特点及现有资源,设计3种船用脱硫装置特种不锈钢管焊接工艺.为确保新焊接工艺满足设计要求,体现实用性和经济性,对焊接方法、焊材种类进行遴选,并进行焊接试验以优化各项焊接参数.试验结果表明,管材焊接接头的各项性能满足设计及规范要求,新焊接工艺通过评定并得到船级社认可.经实船应...