检索结果-内蒙古大学图书馆

7th IEEE International Conference on High Voltage Engineering and Application, ICHVE 2020

作者： Bin, Ding Jingwen, Liu Jianning, Chen Yuanxiang, Zhou Xuewei, Wang Jiamin, Ge Xiong'an Power Supply Company State Grid Baoding China Tsinghua University China State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Department of Electrical Engineering Beijing China Xinjiang University Department of Electrical Engineering Urumqi China

ISBN: (纸本)9781728155111

With the rapid development of ultra-high voltage (UHV) transmission technology in China, insulation diagnosis for power equipment has been applied widely to improve the reliability of the giant power system. Partial discharge (PD) detection, with the advantages of high precision and convenient deployment, plays an important role in defect detection, location, and classification. However, the low signal to noise ratio (SNR) of PD signals and poor electromagnetic environment make it difficult to extract useful features from PD signals. To distinguish the PD signals from noise, a noise reduction method based on deep learning is proposed in this paper. With short-time Fourier transform (STFT) technology, time-domain PD signals with various noise were first transformed into time-frequency domain patterns. After preprocessing the raw pattern, a deep convolutional neural network (CNN) was built, trained, and tuned for noise reduction of PD signals. Finally, the noise reduction model was verified and compared with the traditional method based on wavelet analysis. The results demonstrate that noise reduction mothed based on deep learning can restore the PD signals with more than 90% noise reduced. Given the advantage that the convolution kernel could sense both the time-related information and the frequency-related information in a spectrum simultaneously, the DnCNN model performs better than wavelet analysis. The noise reduction model proposed in this paper is based on new generation artificial intelligence, providing a new approach for PD signal restoration, which promotes the reliability of the power system. © 2020 IEEE.

关键词： Partial discharges

来源：评论

学校读者我要写书评

暂无评论

A Two-level Energy Storage System for Wind Energy systems

A Two-level Energy Storage System for Wind Energy Systems

引用

2011 International Conference of Environmental Science and Engineering（ICESE 2011）

作者： Xi Xiao Hu Yi Qing Kang Jinfeng Nie State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Tsinghua University

Wind power outputs fluctuate with the changing of wind speed. The use of energy storage equipment is considered a reasonable solution to suppress wind power fluctuations. An energy storage mode may have its disadvantages over the others, for example, capacity limits, dynamic response, higher prices or shorter lifetime. Moreover, wind power fluctuations are present at different frequencies, to demand the energy storage to offer power support in different time ranges. To improve the performance, in this paper, a combined energy storage mode is discussed to meet the shortterm and long-term energy storage requirement for wind power. Short-term energy storage is designed to meet the fast-changing power, using such as super capacitors. Long-term energy is designed to meet the large-scale capacity requirement using Li-ion battery or Vanadium Redox Battery(VRB). By analyzing the actual data of wind power outputs, the capacities of the two kinds of energy storage means are given as an example of the method.

关键词： Wind power energy storage capacity designing

来源：评论

学校读者我要写书评

暂无评论

Modeling of Large-Scale Hydrogen Storage System Considering Capacity Attenuation and Analysis of Its Efficiency Characteristics

引用

Energy Engineering 2024年第2期121卷 291-313页

作者： Junhui Li Haotian Zhang Cuiping Li Xingxu Zhu Ruitong Liu Fangwei Duan Yongming Peng Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of Education(Northeast Electric Power University)Jilin132012China Ministry of Science and Technology Electric Power Research Institute of State Grid Liaoning Electric Power Co.Ltd.Shenyang110006China Northeast Electric Power Dispatching Control Center Northeast Branch of State Grid Corporation of ChinaShenyang110180China

In the existing power system with a large-scale hydrogen storage system,there are problems such as low efficiency of electric-hydrogen-electricity conversion and single modeling of the hydrogen storage *** order to improve the hydrogen utilization rate of hydrogen storage system in the process of participating in the power grid operation,and speed up the process of electric-hydrogen-electricity *** article provides a detailed introduction to the mathematical and electrical models of various components of the hydrogen storage unit,and also establishes a charging and discharging efficiency model that considers the temperature and internal gas partial pressure of the hydrogen storage *** models are of great significance for studying and optimizing gas storage *** these models,the performance of gas storage units can be better understood and *** studies are very helpful for improving energy storage efficiency and sustainable *** factors affecting the charge-discharge efficiency of hydrogen storage units are *** integrating the models of each unit and considering the capacity degradation of the hydrogen storage system,we can construct an efficiency model for a large hydrogen storage system and power conversion *** addition,the simulation models of the hydrogen production system and hydrogen consumption system were established in MATLAB/*** accuracy and effectiveness of the simulation model were proved by comparing the output voltage variation curve of the simulation with the polarization curve of the typical hydrogen production system and hydrogen consumption *** results show that the charge-discharge efficiency of the hydrogen storage unit increases with the increase of operating temperature,and H2 and O2 partial voltage have little influence on the charge-discharge *** the process of power conversion system converter rectification operation,its efficiency decreases wi

关键词： Hydrogen storage system simulation modeling electrolyzer fuel cell capacity loss

来源：评论

学校读者我要写书评

暂无评论

A Practical Fusion Localization Method for Autonomous Vehicles in Poor GPS Areas 5

A Practical Fusion Localization Method for Autonomous Vehicl...

引用

5th CAA International Conference on Vehicular control and Intelligence, CVCI 2021

作者： Deng, Jianqiang Chen, Jian Wang, Qi Zhang, Xinfang Zhejiang University State Key Laboratory of Fluid Power Mechatronic Systems College of Control Science and Engineering Hangzhou310027 China Zhejiang University State Key Laboratory of Fluid Power Mechatronic Systems School of Mechanical Engineering Hangzhou310027 China

ISBN: (纸本)9781665408462

Most of the existing intelligent vehicle navigation methods depend significantly on an accurate Global Positioning System (GPS). However, when the GPS signal drifts or loses, the navigation task will fail. To get rid of the influence of low precision positioning, we propose a novel fusion localization method for autonomous vehicles in low positioning accuracy areas. Specifically, key points with obvious features in the previous frame of the point cloud are extracted, converted to the next frame of the point cloud through the GPS data, and detect whether these features still exist to determine the GPS state at this time. Moreover, a detachable fusion positioning module based on LIDAR odometry is proposed and used for localization when the GPS signal is drifting or invalid. Furthermore, through real-world experiments, the proposed method was proven effective in the scene of GPS signal drift and failure. © 2021 IEEE.

关键词： Global positioning system

来源：评论

学校读者我要写书评

暂无评论

A beam flexure-based nanopositioning stage supporting laser direct-write nanofabrication

引用

Science China(Physics,Mechanics & Astronomy) 2016年第8期59卷 50-55页

作者： Zhen Zhang Peng Wang Peng Yan YingChun Guan State Key Laboratory of Tribology and Institute of Manufacturing Engineering Department of Mechanical EngineeringTsinghua University Beijing Key Lab of Precision/Ultra-precision Manufacturing Equipments and Control Tsinghua University State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang University Key Laboratory of High-efficiency and Clean Mechanical Manufacture Ministry of Education School of Mechanical EngineeringShandong University School of Automation Science and Electrical Engineering Beihang University School of Mechanical Engineering and Automation Beihang University

A nanopositioning system of both millimetric stroke and nanometric tracking accuracy is a key component for nanofabrication in many applications. In this paper, a novel bi-axial beam-flexure nano servo stage is proposed to support a direct writing system for femtosecond laser nanofabrication. The important features of the stage lie in: a mirror symmetric instead of rotational symmetric configuration is adopted to restrict cross axis coupling, and a novel Z-shaped guidance module is proposed to achieve relative large linear stiffness range, in addition a redundant constraints module is introduced to increase off-axis stiffness of the stage. Mechanical analysis and system identification are provided, with which a feedback control algorithm demonstrates the tracking capability for laser fabrication purposes. Based on the fabricated XY nano-stage, real time control and measurements are deployed, demonstrating the millimetric operating workspace and 77.8 nm(RMS) error of tracking a circular trajectory.

关键词： laser nanofabrication direct writing servo and control system

来源：评论

学校读者我要写书评

暂无评论

Modeling and SOC estimation of lithium iron phosphate battery considering capacity loss

引用

Protection and control of Modern power systems 2018年第1期3卷 61-69页

作者： Junhui Li Fengjie Gao Gangui Yan Tianyang Zhang Jianlin Li School of Electrical Engineering Northeast Electrical Power UniversityJilinChina Dongying Electric Power Supply Company State Grid Shandong Electric Power CompanyDongyingChina State Key Laboratory of Operation and Control of Renewable Energy&Storage Systems China Electric Power Research InstituteBeijingChina

Modeling and state of charge(SOC)estimation of Lithium cells are crucial techniques of the lithium battery management *** modeling is extremely complicated as the operating status of lithium battery is affected by temperature,current,cycle number,discharge depth and other *** paper studies the modeling of lithium iron phosphate battery based on the Thevenin’s equivalent circuit and a method to identify the open circuit voltage,resistance and capacitance in the model is *** improve the accuracy of the lithium battery model,a capacity estimation algorithm considering the capacity loss during the battery’s life *** addition,this paper solves the SOC estimation issue of the lithium battery caused by the uncertain noise using the extended Kalman filtering(EKF)algorithm.A simulation model of actual lithium batteries is designed in Matlab/Simulink and the simulation results verify the accuracy of the model under different operating modes.

关键词： Lithium-iron battery Battery model Capacity fading state of charge estimation

来源：评论

学校读者我要写书评

暂无评论

Purge Strategy for PEM Fuel Cells Considering Economy and Durability 7

Purge Strategy for PEM Fuel Cells Considering Economy and Du...

引用

7th CAA International Conference on Vehicular control and Intelligence, CVCI 2023

作者： Gao, Yujia Kumar, Lalitesh Chen, Jian Sharma, Harsh Mohan The State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical Engineering Zhejiang University Hangzhou310058 China The State Key Laboratory of Fluid Power and Mechatronic Systems College of Control Science and Engineering Zhejiang University Hangzhou310027 China

ISBN: (纸本)9798350340488

In this paper, a dynamic model is developed based on the phase change of water to predict the accumulation of impurities under different operating conditions. Based on the goal of improving the durability of the stack, a liquid water accumulation index is proposed. The stack purge interval is selected based on the liquid water accumulation index. In addition, the cost of purging hydrogen was introduced to calculate the energy utilization of the purging process. The simulation results show that the proposed model with rate of nitrogen below a certain threshold is considerably more effective in stopping the purge duration as compared to the voltage dropping purge stopping strategy, effectively improving the economy of purging. © 2023 IEEE.

关键词： Anode purge Durability Oriented Purging PEM Fuel cell

来源：评论

学校读者我要写书评

暂无评论

Evaluating Comprehensive Development Quality of a Regional power Grid by Using an Integrated Multi-criteria Decision-Making Methodology 6

Evaluating Comprehensive Development Quality of a Regional P...

引用

2019 6th International Conference on Advanced Composite Materials and Manufacturing Engineering, ACMME 2019

作者： Zhang, Xiaodong Qin, Kaiming Si, Ruihua Ge, Xianjun State Grid Henan Electric Power Company Zhengzhou450018 China State Key Laboratory of Power System and Power Generation Equipment Control and Simulation Department of Electrical Engineering Tsinghua University HaidianBeijing100084 China

Due to the economic situation changes and the continuous expansion of new energy power in China, a new evaluation methodology based on multi-criteria decision making (MCDM) should be proposed to promote the comprehensive development of the new regional power grid. Some criteria were selected to constitute an indicator system from the perspectives of the safety reliability, network structure and economic benefit. Then, an integrated evaluation model was proposed based on fuzzy AHP method and VIKOR method was applied to calculate a series of comprehensive evaluation indexes. A regional power grid was chosen as an empirical analysis to demonstrate the feasibility of the evaluation system. © Published under licence by IOP Publishing Ltd.

关键词： Decision making

来源：评论

学校读者我要写书评

暂无评论

Consensus-Based Distributed Economic Dispatch with Optimized Transition Matrix

Consensus-Based Distributed Economic Dispatch with Optimized...

引用

IEEE power and Energy Society General Meeting

作者： Xinfei Yan Haiwang Zhong Jianxiao Wang Zhenfei Tan State Key Laboratory of Control and Simulation of Power Systems and Generation Equipments Beijing China

With an increasing penetration of distributed energy resources (DERs) in Energy Internet, there is a surge of interest in distributed economic dispatch (DED) problems. The existing literature mainly focuses on average consensus algorithms, the convergence of which remains a bottleneck in practical applications. To improve the convergence rate of DED, this paper proposes a consensus algorithm based on optimized transition matrix (TM) of Markov chain. A DED model is firstly developed under a consensus-based information exchange architecture, in which a generator only communicates with its neighbors. Thus DED is implemented in an iterative manner with generators exchanging information according to a predefined TM. In contrast to the aver-agely weighted TM, we minimize the Frobenius norm (F-norm) of the TM in order to limit the eigenvalues that greatly influence the convergence rate of DED. Additionally, a virtual power method is introduced to meet generators' power limits by reformulating the power allocation ratio. Case studies verify the effectiveness and efficiency of the proposed algorithm.

关键词：

来源：评论

学校读者我要写书评

暂无评论

Applicable range analysis of optimized single-terminal fault location algorithm

Applicable range analysis of optimized single-terminal fault...

引用

2011 International Conference on Advanced power System Automation and Protection, APAP 2011

作者： Huang, Tian-Xiao Dong, Xin-Zhou Shi, Shen-Xing Wang, Bin State Key Lab. of Control and Simulation of Power Systems and Generation Equipments Dept. of Electrical Engineering Tsinghua University Haidian District Beijing 100084 China

ISBN: (纸本)9781424496198

Impedance method and single terminal travelling wave method are analyzed in paper, applicable scope of optimized solution is presented. Impedance method is of high robustness but low accuracy. Single terminal travelling wave method offers high accuracy but poor robustness. Optimized solution combines these two methods together, takes advantages of both methods. It is a great enhancement to single terminal fault location. This paper analyzed theoretical basis of optimized solution, proposed the calculation algorithm of fault location range using impedance method. Analyses of impedance method and single terminal travelling wave method show that the optimized solution is suitable for engineering application. Error analysis is proved correct by simulation. © 2011 IEEE.

关键词： Location

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：