Survey on Passivity Based Control of Induction Machine

Induction machines (IM) constitute a theoretically interesting and practically important class of nonlinear systems. They are frequently used as wind generators for their power/cost ratio. They are described by a fifth‐order nonlinear differential equation with two inputs and only three state variables available for measurement. The control task is further complicated by the fact that IM are subject to unknown (load) disturbances and the parameters can be of great uncertainty. One is then faced with the challenging problem of controlling a highly nonlinear system, with unknown time‐varying parameters, where the regulated output, besides being unmeasurable, is perturbed by an unknown additive signal. Passivity‐based control (PBC) is a well‐established structure‐preserving design methodology which has shown to be very powerful to design robust controllers for physical systems described by Euler‐Lagrange equations of motion. PBCs provide a natural procedure to "shape" the potential energy yielding controllers with a clear physical interpretation in terms of interconnection of the system with its environment and are robust vis á vis to unmodeled dissipative effects. One recent approach of PBC is the Interconnection and Damping Assignment Passivity‐Based Control (IDA‐PBC) which is a very useful technique to control nonlinear systems assigning a desired (Port‐Controlled Hamiltonian) structure to the closed‐loop. The aim of this paper is to give a survey on different PBC of IM. The originality of this work is that the author proves that the well known field oriented control of IM is a particular case of the IDA‐PBC with disturbance.     

基于5G边缘云的港口统一通信方案研究与实践

5G边缘云具有分布式、灵活组网、快速部署和本地流量分流等优势，在港口等垂直工业领域有很广泛的应用前景，同时对实现港口统一通信也提出了一定的要求。在研究基于5G边缘云的港口统一通信架构的基础上，提出了针对港口现场全域各类要素实现全面感知、支撑自动化业务改造的5G边缘云功能框架。此功能框架能很好地适用于港口场景的有线无线网络融合的统一承载，可作为目前复杂环境下的港口网络统一通信的网络基础设施。最后在某港口码头上对该方案进行了实际验证。     

变换炉卸料口接管焊缝裂纹产生的原因及处理

针对变换炉运行一段时间后卸料口接管与变换炉本体焊接处出现的贯穿性裂纹,分析其原因,并在运行过程中采取了一系列预处理措施,有效控制了泄漏;在检修时制定了改造措施,最终消除了这一设备缺陷。     

Ersatzneubau der Kajen im Marinestützpunkt Wilhelmshaven

Replacement construction of quays at the naval base in Wilhelmshaven At the naval base of Wilhelmshaven the quay walls and dolphins of a floating bridge system are being renewed. The existing quays show extensive damage and stability deficits. In particular, microbially induced corrosion (MIC) on the back of the old sheet piling lead to rust corrosion of the old sheet pile walls. Content of the report is the conceptual and structural implementation of the measure quay renewal that has been executed since the beginning of 2013. Special attention is paid to the security of the stock during the construction period, the selected corrosion protection measures as well as the requirements for the installation of combined sheet piling.     

集约化信息管线的防护能力与对策措施

上海信息港信息管线的集约化建设目前多采用电信光缆沟建设模式 ,对其开展的研究主要是关注其在和平时期使用的便捷与安全性 ,而对其在战时防护能力是否足够则缺乏重视和研究 ,存在问题似还较多。本文对集约化信息管线中人孔结构的防护能力、管线系统的规划等问题进行了分析研究 ,并相应地提出了旨在提高集约化信息管线的防护能力的对策措施。     

喷射合成纤维混凝土技术的研究及应用

喷射混凝土施工工艺无疑是最令人满意的结构混凝土修补方法之一.为在水运工程中推广应用喷射混凝土施工工艺,针对提高喷射混凝土耐久性及喷射混凝土施工工艺的适用性开展了试验研究工作.本文介绍了喷射合成纤维混凝土的性能、特点和施工工艺以及在修复加固工程中的应用实例.     

低NOx燃烧器的研制

介绍了采用条缝型火孔结构、稳定火焰、降低火孔热强度，提高一次空气系数，同时采取措施，控制二次空气的自由供入，达到降低NOx的效果；分析和探讨了影响NOx生成的诸多因素及抑制NOx生成的方法。     

澳大利亚GPA 5000t/h装船机除尘系统设计

散货码头设备在转运物料过程中,难免产生扬尘,对环境造成污染。为了最大限度减少灰尘,澳大利亚装船机上采用了干式除尘、喷淋除尘、封闭控尘等一系列的防尘措施,取得了良好的抑尘效果。     

天津港和横滨港发展环境及开发利用比较研究

天津港和横滨港皆以建设现代化国际港口为目标,但其发展条件、产业特征、发展理念和所处的发展阶段存在诸多差异.本文通过对上述两港的区位、自然条件、政策支撑等对外发展环境以及土地利用、功能布局、产业发展等对内开发利用两方面进行比较,总结了横滨港口发展的经验,以期为天津港未来的发展提供可供参考的借鉴.     

二级液环泵吸、排气口影响分析

针对二级液环泵吸气孔的形状对液环泵内工作介质的流动轨迹、湍流程度,对液环泵的能量耗费大等特点,应用Solidworks flow simulation软件对液环泵吸排气口的形状对泵性能的影响进行有限元分析,为今后二级液环泵的应用提供理论依据。