The Research and Realization of Automatic Frequency and LoadConditioner in Marine Power Station based on PLC [PDF]
, 2007 船舶电站自动化是无人机舱的一个重要部分，是国内外船电专家一直在探索和研究的课题。国外发达国家利用PLC配合计算机对船舶电站进行控制，已构成船舶全自动电站。本课题来源于福建省高等学校科研项目《高性能的船舶电站可编程序自动调频调载装置》，采用PLC对船舶电站进行控制，其研究对我国船舶电站自动化实现与发展是一次有意义的尝试和探索 。 本文详细地阐述了调频调载的原理和实现方法。通过对当前国内外船舶电气自动化发展的最新技术的研究，提出采用PLC实现船舶电站的自动调频调载 ...
黄丽卿
core
Research on an Ultra-Short-Term Wind Speed Prediction Method Based on Improved Combined Neural Networks [PDF]
Ultra-short-term wind speed prediction is the key to ensure the implementation effect of wind turbine pitch angle feedforward control, and has an important impact on improving the environmental adaptability of wind turbines.
FANG Yuan +5 more
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Shiyou jixie, 2014 海洋井架不但承受工作载荷，同时也承受风载荷以及海洋环境载荷。运用ANSYS有限元软件建立了HJJ675/52-T型海洋井架模型，对井架所受的风载荷进行了计算，对井架进行了模态分析和谐响应分析，指出了井架在风暴自存工况下的薄弱环节。建模时井架上所带的扶梯、栏杆等附件以及天车、游车、顶驱、二层台等装置视为集中载荷施加于相应节点上。分析结果表明，节点的位移频率曲线反映了井架的共振特性；实际操作中应根据钻井工况的不同，调节绞车的转速使其避开井架的固有频率，以免引起井架共振。
张辉 +4 more
doaj
Level walking stride frequency forecast based on Kalman filter model [PDF]
, 2015 现有智能下肢的控制策略都是以刚完成的一步的步频为调节阻尼的依据,调整好的阻尼只能在下一步摆动期生效,因此该控制策略是滞后的,无法做到实时控制,在步频变化频繁的场合难以适用。本文方法利用足底压力传感获取步频数据,然后通过卡尔曼预测方程由已完成的步频预测即将迈出的下一步步频。在模拟日常生活平地行走步频变化的实验中,所预测的下一步步频与后验值之间偏差比跟随方法的偏差大约减小了10%。该方法实时性好,为改善智能下肢的性能提供了新的可行性方案。The adjusted damping of intelligent
余韬 +4 more
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Gaoya dianqi在储能换流器（power conversion system，PCS）控制系统中采用了虚拟同步机（virtual synchronous generation，VSG）控制策略，使其拥有与同步发电机相近的旋转及励磁特性。提出一种新型自适应虚拟惯量VSG控制方法，引入频率变化率表征虚拟惯量，减少储能VSG频率调节时的调节偏差与调节时间；针对储能系统常见低频扰动，采用虚拟电力系统静态稳定器（power system stabilizer，PSS）调节环节，增加VSG控制系统阻尼比，维持频率稳定。MATLAB/
冯晓静 +4 more
doaj
Guangtongxin yanjiu, 2016 以低损耗材料聚乙烯为基底,设计了一种新型的太赫兹光子晶体光纤,并利用全矢量有限元法对其单模截止频率、色散和损耗进行了数值模拟。结果表明,改变包层空气孔周期、空气孔直径和纤芯空气孔直径,可以调节太赫兹单模传输的频率范围。当包层空气孔周期为400μm、包层空气孔直径为100μm、纤芯空气孔直径为40μm时,不仅可以获得0.15THz的宽频带单模传输范围,而且在0.55THz频率范围内波导色散可以控制在±0.5ps/（nm·km）,且模式的限制损耗随频率的增大逐渐减小,同时在2.8THz处获得最小传输损耗3 ...
刘延君 +7 more
doaj
Study on Double Phase-Locked Loop on the Synthetic Inertia Control of Offshore Wind Farm Frequency Regulation [PDF]
To build the new power system with the main body of new energy, the offshore wind farm (OWF) is an important part and has been rapidly developed in coastal cities.
CAI Chuanwei +5 more
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Dynamic Power Decoupling Control of Virtual Synchronous Generator Based on Improved Virtual Impedance [PDF]
ObjectivesWhen a virtual synchronous generator (VSG) is connected to a medium and low voltage distribution network, the line impedance exhibits resistive and inductive characteristics, resulting in strong coupling in the VSG output power.
REN Mingwei +4 more
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Global Smartphone Technological Innovation Capacity Analysis Based on Latent Semantic Indexing and Vector Space Model Method [PDF]
This paper analyzes the global competitive landscape of smartphone technological innovation capacity using the latent semantic indexing （LSI） and the vector space model （VSM）. It integrates the theory of technological ecological niches and evaluates four
CHEN Wanming, ZHANG Yuwen
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Beam Size Measurement by Optical Diffraction Radiation and Laser System for Compton Polarimeter [PDF]
, 2012 Beam diagnostics is an essential constituent of any accelerator, so that it is named as "organs of sense" or "eyes of the accelerator." Beam diagnostics is a rich field.
Liu, Chuyu
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