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基于模型预测控制的光储发电系统VSG频率控制方法 [PDF]

open access: yes全球能源互联网, 2022
随着光伏发电装机规模大幅提升,电力系统转动惯量不断降低,虚拟同步发电机(virtual synchronous generator,VSG)技术被广泛采用以应对日益严峻的电网稳定性问题。为进一步提高VSG技术对系统稳定性的改善作用,提出基于模型预测控制的VSG频率控制方法。该方法首先在同步发电机转子运动方程和逆变器下垂控制方程基础上建立VSG可优化的离散模型,再通过模型预测控制(model predictive control,MPC)预测VSG转子角频率的运动轨迹 ...
李帅虎   +3 more
doaj   +3 more sources

The political origins of platform economy regulations. Understanding variations in governing Airbnb and Uber across cities in Switzerland

open access: yesPolicy &Internet, Volume 14, Issue 4, Page 736-754, December 2022., 2022
Abstract In the past decade, digital platforms have entrenched themselves within key urban sectors, opening the way for radical changes in traditional industries. Along with new opportunities for city residents, globally operating platforms such as Airbnb and Uber also raised specific challenges, sparking calls for adequate responses by city ...
Marine C. Benli‐Trichet   +1 more
wiley   +1 more source

Modeling total predation to avoid perverse outcomes from cat control in a data‐poor island ecosystem

open access: yesConservation Biology, Volume 36, Issue 5, October 2022., 2022
Abstract Data‐hungry, complex ecosystem models are often used to predict the consequences of threatened species management, including perverse outcomes. Unfortunately, this approach is impractical in the many systems that have insufficient data to parameterize ecosystem interactions or reliably calibrate or validate such models.
Michaela Plein   +9 more
wiley   +1 more source

输入受限的漂浮基多柔性空间机器人轨迹跟踪的混合控制及振动主动抑制

open access: yesKongjian kexue xuebao, 2023
空间机器人在实际运作中往往会遇到控制系统输入受限的情况,这将严重影响系统的控制品质。考虑输入受限的情况,对漂浮基多柔性空间机器人系统进行研究。通过对系统进行运动学和动力学分析,构建系统的动力学方程。采用奇异摄动方法,将刚柔耦合系统分为慢变子系统和快变子系统,并为各个子系统设计控制方法。最终提出由改进的鲁棒滑模模糊控制方法、速度差值反馈控制法和线性二次最优控制方法组成的混合控制方法。该控制方法能够主动减小空间机器人完成期望运动所需的力矩,使系统适应输入受限的工作条件;同时能够补偿系统的不确定参数和外部干扰,
谢 立敏, 于 潇雁
doaj   +1 more source

考虑风电机组故障穿越特性的电压反复波动机理分析与抑制 [PDF]

open access: yes全球能源互联网, 2022
近年来,大规模风电汇集系统实际运行中频繁出现电压反复波动现象,具有波动幅度大、波动峰谷值切换速率达秒级的特点,与风能随机性、无功补偿装置动作引起的电压波动现象具有显著区别,运行中多次造成风电机组因连续穿越失败而脱网,严重威胁了电网安全稳定运行。上述现象涉及风电机组故障穿越策略与弱电网功率-电压特性的耦合作用,难以通过传统电力系统电压稳定分析方法直接解释。提出了考虑风电机组低电压穿越特性的系统有功-电压曲线(PV曲线)分析方法,准确刻画波动过程中系统运行点轨迹变化规律,并通过仿真进行了验证。在此基础上 ...
吴林林   +6 more
doaj   +1 more source

International clinical practice recommendations on the definition, diagnosis, assessment, intervention, and psychosocial aspects of developmental coordination disorder – Chinese (Mandarin) translation

open access: yesDevelopmental Medicine &Child Neurology, Volume 61, Issue 3, Page E1-E35, March 2019., 2019
目的 本国际临床指南由欧洲残疾儿童学会(the European Academy of Childhood Disability,EACD)牵头制定,旨在解决发育性协调障碍(developmental coordination disorder,DCD)的定义、诊断、评估、干预以及与社会心理方面的临床应用关键问题。 方法 本指南针对五个领域的关键问题,通过文献综述和专家团队的正式讨论达成共识。为保证指南的循证基础,以“机制”、“评估”和“干预”为检索词, 对2012年更新以来提出的最新建议以及新增的“社会心理问题”和“青少年/成人”为检索词进行检索。根据牛津大学循证医学中心证据等级 (证据水平 [level of evidence, LOE]1–4) 将结果进行分类,最终转化为指南建议。并由国际 ...
Jing Hua   +6 more
wiley   +1 more source

一类非仿射系统的执行依赖启发式在线跟踪控制

open access: yes智能科学与技术学报, 2021
针对非仿射系统的跟踪控制问题,提出一种基于执行依赖启发式动态规划(ADHDP)结构的在线设计方法。首先,考虑一类未知非仿射系统,进行从跟踪控制问题到误差调节问题的转换;然后,设计基于 ADHDP结构的跟踪控制器,并采用在线学习的方式,实现系统控制与执行网络和评判网络的训练同步,使得系统状态能够跟踪期望轨迹;最后,通过一个仿真实例验证所提方法的有效性。
赵慧玲, 王鼎, 任进
doaj  

Organ‐specific ozone and nitrogen legacies strengthen substrate control over litter decomposition

open access: yesFunctional Ecology, Volume 40, Issue 8, Page 2548-2559, August 2026.
Read the free Plain Language Summary for this article on the Journal blog. Abstract Elevated tropospheric ozone (O3) and nitrogen (N) deposition are concurrent atmospheric changes that strongly influence terrestrial carbon cycling, yet their combined effects on below‐ground decomposition remain poorly understood.
Xiaofan Hou   +8 more
wiley   +1 more source

Prolonged Nutrient Enrichment Slows the Recovery of Biodiversity and Productivity After Its Cessation

open access: yesGlobal Change Biology, Volume 32, Issue 7, July 2026.
Grassland recovery following nutrient cessation is asymmetric and strongly shaped by nutrient enrichment history. Higher nutrient addition rates and longer enrichment duration caused larger departures from control conditions, with biomass recovering more rapidly than species richness over decadal timescales.
Miao He   +8 more
wiley   +1 more source

Laser‐guided thin‐film self‐rolling for asymmetric small‐scale swimmers

open access: yesRare Metals, Volume 44, Issue 8, Page 5607-5620, August 2025.
Graphical abstract AbstractSmall‐scale robots are promising miniaturized devices in biomedicine. Thin‐film self‐assembly is a commonly used strategy to fabricate tubular small‐scale robots. However, the existing methods have limitations like complex manufacturing processes and limited control of self‐assembly behavior.
Yi Chen   +11 more
wiley   +1 more source

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