检索结果-内蒙古大学图书馆

Energy-balancing dual-port grid-forming control for VSC-HVDC systems

IFAC-PapersOnLine 2023年第2期56卷 6447-6452页

作者： Irina Subotić Dominic Groß Automatic Control Laboratory ETH Zürich Switzerland Department of Electrical and Computer Engineering University of Wisconsin-Madison USA

This work examines energy-balancing dual port grid-forming (GFM) control for high-voltage direct current (HVDC) transmission. In contrast to the state-of-the-art, HVDC converters controlled in this way do not require assigning GFM and grid-following roles to different converters. Moreover, this control enables primary frequency control and inertia support through HVDC links. A detailed stability and steady-state analysis results in conditions on the control gains such that i) the overall hybrid dc/ac system is stable, ii) asynchronous ac areas are quasi-synchronous, and iii) circulating power in cyclic topologies is avoided. Finally, a high-fidelity case study is used to illustrate and verify the analytical results.

关键词： Power systems Power systems stability Grid-forming control HVDC transmission

来源：评论

学校读者我要写书评

暂无评论

Real-time Safety Helmet-wearing Detection Based on Improved YOLOv5

引用

computer Systems Science & engineering 2022年第12期43卷 1219-1230页

作者： Yanman Li Jun Zhang Yang Hu Yingnan Zhao Yi Cao NARI Nanjing Control System Ltd. Nanjing210032China School of Computer Nanjing University of Information Science&TechnologyNanjing210044China Department of Electrical and computer Engineering University of WindsorWindsorN9B 3P4Canada

Safety helmet-wearing detection is an essential part of the intelligentmonitoring system. To improve the speed and accuracy of detection, especiallysmall targets and occluded objects, it presents a novel and efficient detectormodel. The underlying core algorithm of this model adopts the YOLOv5 (YouOnly Look Once version 5) network with the best comprehensive detection performance. It is improved by adding an attention mechanism, a CIoU (CompleteIntersection Over Union) Loss function, and the Mish activation function. First,it applies the attention mechanism in the feature extraction. The network can learnthe weight of each channel independently and enhance the information dissemination between features. Second, it adopts CIoU loss function to achieve accuratebounding box regression. Third, it utilizes Mish activation function to improvedetection accuracy and generalization ability. It builds a safety helmet-wearingdetection data set containing more than 10,000 images collected from the Internetfor preprocessing. On the self-made helmet wearing test data set, the averageaccuracy of the helmet detection of the proposed algorithm is 96.7%, which is1.9% higher than that of the YOLOv5 algorithm. It meets the accuracy requirements of the helmet-wearing detection under construction scenarios.

关键词： Safety helmet wearing detection object detection deep learning YOLOv5 Attention Mechanism

来源：评论

学校读者我要写书评

暂无评论

Comparative Techno-Economic-Environmental Analysis of HVDC and HVAC Technologies for an Offshore Wind Farm in China 7

Comparative Techno-Economic-Environmental Analysis of HVDC a...

引用

7th IEEE Conference on Energy Internet and Energy System Integration, EI2 2023

作者： Liang, Yingqi Wu, Shuangxi Liu, Yang Fu, Dongqiang Lee, Yan Rui Guo, Gengrui Luo, Tianhao Wang, Tianhao National University of Singapore Department of Electrical and Computer Engineering Singapore117576 Singapore Electric Power Dispatching and Control Center of Guangdong Power Grid Co. Ltd. Guangzhou510060 China

ISBN: (纸本)9798350345094

DC collection systems offer advantages by reducing the weight and size of DC cables without requiring reactive power compensation. This enables the replacement of the bulky 50/60 Hz transformers typically used in AC collection systems on offshore platforms with smaller medium-frequency transformers in DC collection configurations. Nonetheless, challenges persist in implementing high-power DC-DC converters with high-voltage transformation ratios and DC protection methods in DC collection systems. It is worth noting that while HVDC (High Voltage DC) transmission can transfer offshore wind power from collection systems to onshore grids, DC collection systems do not always result in fewer power conversion stages compared to AC collection systems. To tackle these challenges, this paper conducts a comparative analysis of the technological, economic, and environmental aspects of DC and AC collection systems for offshore wind farms, using a wind farm in China as an illustrative example. Our approach involves an innovative method for estimating losses and a technical comparison. Simulation results validate that DC collection systems exhibit higher total losses than AC collection systems. We also explore the impact of collection bus voltages on these losses in DC systems. Additionally, we develop an economic cost assessment method, and the sensitivity analysis results confirm that cost reductions primarily stem from the reduced size of DC cables and offshore platforms rather than improvements in DC protective devices and DC-DC converters. Lastly, we investigate the environmental implications of these systems. © 2023 IEEE.

关键词： Offshore wind farms

来源：评论

学校读者我要写书评

暂无评论

FMCW Radar-Based Human Activity Recognition: A Machine Learning Approach for Elderly Care

FMCW Radar-Based Human Activity Recognition: A Machine Learn...

引用

IEEE Conference on Wireless Communications and Networking

作者： Mohammadreza Mashhadigholamali Ali Samimi Fard Samaneh Zolfaghari Hajar Abedi Mainak Chakraborty Luigi Borzí Masoud Daneshtalab George Shaker Department of Control and Computer Engineering Politecnico di Torino Turin Italy School of Innovation Design and Engineering Mädlardalen University Västerås Sweden Department of Electrical and Computer Engineering University of Waterloo Waterloo Ontario Canada

ISBN: (数字)9798350368369

ISBN: (纸本)9798350368376

In this paper, we propose a novel system prototype for human activity recognition using a low-cost, low-power millimeter-wave (mmWave) frequency-modulated continuous wave (FMCW) radar. Our approach applies the Fast Fourier Transform on the slow time axis and employs a Capon filter to generate range-Doppler, range-azimuth, and range-elevation maps, respectively. It can also effectively mitigate noise and multipath effects. We then use principal component analysis for feature reduction, reducing the dimensionality of the feature vectors extracted from these maps, which can be used to train conventional machine learning classifiers. This approach aims to achieve a balance between computational complexity, accuracy, and overall system performance. Our proposed system demon-strates promising recognition rates and robustness across varying levels of activity granularity, achieving recognition rates from 90.28% for four activities up to 70.97% for seven fine-grained ac-tivities. These findings highlight the potential of millimeter wave radar and suggested range maps combined with conventional machine learning classifiers for noninvasive, privacy-preserving activity recognition, with significant implications for healthcare, elderly care, and ambient assisted living.

关键词： Support vector machines Deep learning Radar imaging Millimeter wave radar Feature extraction Vectors Human activity recognition Older adults Millimeter wave communication Long short term memory

来源：评论

学校读者我要写书评

暂无评论

On the Gaussian Filtering for Nonlinear Dynamic Systems Using Variational Inference 27

On the Gaussian Filtering for Nonlinear Dynamic Systems Usin...

引用

27th International Conference on Information Fusion, FUSION 2024

作者： Liu, Yi Li, Xi Yang, Le Mihaylova, Lyudmila Li, Ji University of Canterbury Department of Electrical and Computer Engineering Christchurch New Zealand National University of Defense Technology State Key Lab of Complex Electromagnetic Environment Effects on Electronics and Information Systems Changsha China University of Sheffield Department of Automatic Control and System Engineering Sheffield United Kingdom Locaris Electronic Technology Co. Ltd Zhengzhou China

ISBN: (纸本)9781737749769

This paper introduces a new variational Gaussian filtering approach for estimating the state of a nonlinear dynamic system. We first assume that the predictive distribution of the state is Gaussian and derive an iterative method for updating the state posterior in the natural parameter space through KullbackLeibler divergence minimization. The obtained update rule is the same as that of the conjugate-computation variational inference technique in Bayesian learning. The derivation here is simpler and more insightful. We then impose a Wishart prior on the inverse of the state prediction covariance to take into account the impact of approximating the state predictive distribution using a Gaussian density on the state posterior estimation. The prediction covariance is identified jointly with the state using variational inference and the established state posterior update rule to achieve the desired Gaussian filtering. Simulation study examines the performance of the proposed filtering framework in target tracking based on bearing and range measurements. © 2024 ISIF.

关键词： Wiener filtering

来源：评论

学校读者我要写书评

暂无评论

Systematic Evolution of 5G/6G Wireless Networks: A Review Standardization, Vision, Application, Security, Requirements, Propagation and Blockchain

Systematic Evolution of 5G/6G Wireless Networks: A Review St...

引用

IEEE International Conference on Automatica (ICA-ACCA)

作者： Héctor Kaschel Sergio Cordero Pablo Adasme Román Osorio Cristian Ahumada Department of Electrical Engineering University of Santiago of Chile Santiago Chile Department of Computer Engineering University National Autonomous of Mexico Ciudad de México México Department of Electrical Engineering University Technical Federico Santa María Valparaíso Chile

ISBN: (数字)9798350378115

ISBN: (纸本)9798350378122

This article presents the systematic evolution of 5G and 6 G wireless networks and the future projections to be considered to face the promising technological change in different sectors, given by the increased efficiency and security, presenting the versions of the different 3GPP reals with a deployment plan until 2028. It also presents the challenges and vision of future generations and typical applications of future 6G wireless networks, along with the above, the characteristics of the applications and international standardization bodies are indicated. Another point analyzed were the problems of radio wave propagation in the different deployment scenarios, whether indoors or outdoors. The problems of link blocking and coverage of telecommunication services for users were analyzed in the field, and the ITU-R P.1410 recommendation was presented, which provides propagation concepts and predictive coverage methods for networks operating between 3 and 60 GHz. Finally, the benefits and advantages of blockchain in 5G and 6G wireless networks are presented, as services dedicated to the management of digital documentation, as is the case of smart agriculture 5.0, smart health and banking entities, among others, which will revolutionize private companies in terms of reducing operating costs and a promising future is also foreseen with the Metaverse-6G, transforming communication, driving innovation in commerce and education to build a more inclusive and egalitarian digital world.

关键词： 6G mobile communication Smart agriculture Technological innovation Systematics 5G mobile communication Wireless networks Smart healthcare Standardization Blockchains Telecommunication services

来源：评论

学校读者我要写书评

暂无评论

Bayesian hypergame approach to equilibrium stability and robustness in moving target defense 63

Bayesian hypergame approach to equilibrium stability and rob...

引用

63rd IEEE Conference on Decision and control, CDC 2024

作者： Zhang, Hanzheng Cheng, Zhaoyang Chen, Guanpu Johansson, Karl Henrik Shanghai Research Institute for Autonomous Intelligent Systems Tongji University Shanghai China University of Chinese Academy of Science Academy of Mathematics and System Science Chinese Academy of Science Beijing China Kth Royal Institute of Technology and the Digital Futures Division of Decision and Control Systems School of Electrical Engineering and Computer Science Stockholm Sweden

ISBN: (纸本)9798350316339

We investigate the equilibrium stability and robustness in a class of moving target defense problems, in which players have both incomplete information and asymmetric cognition. We first establish a Bayesian Stackelberg game model for incomplete information and then employ a hypergame reformulation to address asymmetric cognition. With the core concept of the hyper Bayesian Nash equilibrium (HBNE), a condition for achieving both the strategic and cognitive stability in equilibria can be realized by solving linear equations. Moreover, to deal with players' underlying perturbed knowledge, we study the equilibrium robustness by presenting a condition of robust HBNE under the given configuration. Experiments evaluate our theoretical results. © 2024 IEEE.

关键词： Hierarchical systems

来源：评论

学校读者我要写书评

暂无评论

Confidence-Aware Safe and Stable control of control-Affine Systems

Confidence-Aware Safe and Stable Control of Control-Affine S...

引用

American control Conference (ACC)

作者： Shiqing Wei Prashanth Krishnamurthy Farshad Khorrami Department of Electrical and Computer Engineering NYU Tandon Control/Robotics Research Laboratory School of Engineering 5 Metrotech Center Brooklyn NY USA

ISBN: (数字)9798350382655

ISBN: (纸本)9798350382662

Designing control inputs that satisfy safety requirements is crucial in safety-critical nonlinear control, and this task becomes particularly challenging when full-state measurements are unavailable. In this work, we address the problem of synthesizing safe and stable control for control-affine systems via output feedback (using an observer) while reducing the estimation error of the observer. To achieve this, we adapt control Lyapunov function (CLF) and control barrier function (CBF) techniques to the output feedback setting. Building upon the existing CLF-CBF-QP (Quadratic Program) and CBF-QP frameworks, we formulate two confidence-aware optimization problems and establish the Lipschitz continuity of the obtained solutions. To validate our approach, we conduct simulation studies on two illustrative examples. The simulation studies indicate both improvements in the observer's estimation accuracy and the fulfillment of safety and control requirements.

关键词： Accuracy Observers control systems Eigenvalues and eigenfunctions Safety Trajectory Task analysis

来源：评论

学校读者我要写书评

暂无评论

The Effect of Disturbances on Plant-Model Mismatch Detection using the Plant-Model Ratio: A Surge Tank Case Study

引用

IFAC-PapersOnLine 2024年第22期58卷 24-29页

作者： Heinz K. Mittermaier Johan D. le Roux Ian K. Craig Measurement and Control Division Mintek Randburg South Africa. Department of Electrical Electronic and Computer Engineering University of Pretoria Pretoria South Africa.

The surge tank in a bulk tailings treatment plant aims to reject flow and density disturbances. However, for large disturbances, there may be an inversion in the gain between the water inflow and tank slurry density for a linearized model of the plant. The plant-model ratio (PMR) is a method to diagnose model-plant mismatch (MPM), such as gain-inversion, in the absence of disturbances. This article evaluates the influence of disturbances on the ability of the PMR to diagnose MPM for the surge tank. If the disturbance is measured, as in the case of the surge tank, the PMR is able to detect MPM such as gain-inversion. A controller can be adapted according to the MPM information from the PMR diagnosis.

关键词： controller performance monitoring model predictive control model-plant mismatch process performance monitoring surge tank

来源：评论

学校读者我要写书评

暂无评论

Model-plant mismatch detection for a plant under Model Predictive control: A grinding mill circuit case study

引用

IFAC-PapersOnLine 2023年第2期56卷 11778-11783页

作者： Heinz K. Mittermaier Johan D. le Roux Laurentz E. Olivier Ian K. Craig Department of Electrical Electronic and Computer Engineering University of Pretoria Pretoria South Africa Analyte Control Pretoria South Africa

This articles investigates two different techniques of identifying model-plant mismatch for a grinding mill circuit under model predictive control. A previous attempt at model-plant mismatch detection for a grinding mill, in the form of a partial cross correlation analysis, is used as a benchmark for model-plant mismatch detection and degraded sub-model isolation. This is followed by an investigation of the plant model ratio technique applied to the same system. The plant model ratio technique is able to isolate the sub-model containing a mismatch as well as detect the specific parameter in a first-order-plus-time-delay model responsible for the mismatch. A simulation study is used to quantify and compare the results between the two model-plant mismatch detection methodologies. The results indicate plant model ratio accurately and timeously detects mismatches in sub-models. This allows for system reidentification or controller adaption to ensure optimal process performance. The advantage above partial cross correlation is the parameter diagnosis within the degraded sub-model coupled with the mismatch direction.

关键词： controller performance monitoring grinding mill circuit model predictive control model-plant mismatch process performance monitoring

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：