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Prediction of DC Corona Onset Voltage for Rod-Plane Air Gaps by a Support Vector Machine

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Plasma Science and Technology 2016年第10期18卷 998-1004页

作者：金硕阮江军杜志叶朱琳舒胜文 School of Electrical Engineering Wuhan University Wuhan 430072 China state grid Hubei Electric Power company Technology Training Center Wuhan 430079 China Electric Power Research Institute of state grid fujian Electric Power company Limited Fuzhou 350007 China

This paper proposes a new method to predict the corona onset voltage for a rod- plane air gap, based on the support vector machine （SVM）. Because the SVM is not limited by the size, dimension and nonlinearity of the samples, this method can realize accurate prediction with few training data. Only electric field features are chosen as the input; no geometric parameter is included. Therefore, the experiment data of one kind of electrode can be used to predict the corona onset voltages of other electrodes with different sizes. With the experimental data obtained by ozone detection technology, and experimental data provided by the reference, the efficiency of the proposed method is validated. Accurate predicted results with an average relative less than 3% are obtained with only 6 experimental data.

关键词： corona SVM prediction method electrodes electric fields

Research Progress in Lithium-Excess Disordered Rock-Salt Oxides Cathode

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Energy & Environmental Materials 2022年第4期5卷 1139-1154页

作者： Manxi Wang Xiaochuan Chen Hurong Yao Ganggang Lin Jinhyuk Lee Yuming Chen Qinghua Chen College of Environmental Science and Engineering and College of Physics and Energy Fujian Normal UniversityFuzhou 350000China School of Chemistry Sun Yat-sen UniversityGuangzhou 510275China state grid fujian ehv company Fuzhou 350000China Department of Mining and Materials Engineering McGill UniversityMontrealQC H3A 0C5Canada

The increasing demand for new energy sources has promoted the improvement of the energy storage capacity of lithium-ion batteries(LIBs)that urged the development of higher energy density cathode *** enhancement of the classical cathode in the last 30 years has reached a bottleneck,and then the discovery of the lithium-excess disordered materials has greatly expanded the research space of the cathode *** with the conventional layered oxides,the lithium-excess disordered rock-salt oxides(LEDRXs)with a more stable structure has higher extractable Li^(+)content,even though the inactive high-valent transition metals(TMs)were needed to compensate for the excess Li,which would reduce the total TM redox *** addition,oxygen redox provides additional electron capacity for the materials,which also causes O loss and results in the subsequent poor cycle ***,a series of studies about LEDRXs and their targeted modification measures are summarized,including the prospect of the materials,in order to provide ideas for the design of highperformance ***,the new discoveries and outlook on future research directions of LEDRX cathode materials for LIBs with higher energy density are given.

关键词： disordered rock-salt oxides lithium-excess lithium-ion batteries

Coarse-to-fine visual autonomous unmanned aerial vehicle landing on a moving platform

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Biomimetic Intelligence & Robotics 2023年第1期3卷 65-73页

作者： Qiangqiang Cui Min Liu Xiaoyin Huang Ming Gao IKingtec Intelligent Technology Co. LtdBeijing 100089China state grid Jibei Electric Power company Limited Beijing 100032China state grid Jibei Electric Power Co. Ltd.Beijing EHV Power Transmission CompanyBeijing 102488China

Autonomous unmanned aerial vehicle(UAV)landing is a challenging task,especially on a moving platform in an unstructured *** such a scenario,successful UAV landing is mainly affected by poor UAV localization *** solve this problem,we propose a coarse-to-fine visual autonomous UAV landing system based on an enhanced visual positioning *** landing platform is marked with a specially designed QR code marker,which is developed to improve the landing accuracy when the UAV approaches the landing ***,we employ the you only look once framework to enhance the visual positioning accuracy,thereby promoting the landing platform detection when the UAV is flying far *** framework recognizes the QR code and decodes the position of a UAV by the corner points of the QR ***,we use the Kalman filter to fuse the position data decoded from the QR code with those from the inertia measurement unit ***,the position data are used for UAV landing with a developed hierarchical landing *** verify the effectiveness of the proposed system,we performed experiments in different environments under various light *** experimental results demonstrate that the proposed system can achieve UAV landing with high accuracy,strong adaptability,and *** addition,it can achieve accurate landing in different operating environments without external real-time kinematic global positioning system(RTK-GPS)signals,and the average landing error is 11.5 cm,which is similar to the landing error when using RTK-GPS signals as the ground truth.

关键词： UAV Accurate landing QR code detection YOLOv5 m PnP solver

Performance Analysis of Corroded Grounding Devices with an Accurate Corrosion Model

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CSEE Journal of Power and Energy Systems 2023年第3期9卷 1235-1247页

作者： Yihua Dan Zhanlong Zhang Pengfei Gan Huarui Ye Qiaoyi Li Jun Deng state Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing UniversityChongqing 400030China Test Centre of ehv Transmission company China Southern Power GridGuangzhou 510663China

Grounding devices are significant to the operation of the power transmission line and power *** soil and leakage current can easily cause the corrosion of carbon steel grounding devices,resulting in power ***,most carbon steel grounding devices in service are already corroded,and the accurate calculation of grounding parameters for corroded grounding devices is ***,most existing methods for calculating the grounding parameters of corroded grounding devices usually have the following disadvantages:1)They only consider whether the grounding devices are broken or not,and cannot analyze the grounding parameters of grounding devices with different corrosion degrees;2)They assume that the corroded grounding device is a conductor with a smaller diameter,and ignore the impact of the corrosion product layer,resulting in calculation *** solve the above problems,this paper establishes an accurate corrosion model for grounding devices based on the volume expansion coefficient of corrosion *** grounding parameters calculation method for corroded grounding devices is proposed based on the boundary element method(BEM)and Galerkin’s *** the grounding performance of tower grounding grids with different corrosion degrees in different soils(uniform and layered)is ***,some features of grounding parameters of corroded grounding devices are *** study can accurately calculate the grounding parameters of the corroded grounding devices and has far-reaching engineering significance for the safety of power equipment.

关键词： Corroded grounding devices corrosion product layer grounding parameters volume expansion coefficient

Mobile-Deep Based PCB Image Segmentation Algorithm Research

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Computers, Materials & Continua 2023年第11期77卷 2443-2461页

作者： Lisang Liu Chengyang Ke He Lin School of Electronic Electrical Engineering and Physics Fujian University of TechnologyFuzhou350118China state grid fujian Power Supply Co. Ltd.Xiapu Power Supply CompanyNingde355100China

Aiming at the problems of inaccurate edge segmentation,the hole phenomenon of segmenting large-scale targets,and the slow segmentation speed of printed circuit boards(PCB)in the image segmentation process,a PCB image segmentation model Mobile-Deep based on DeepLabv3+semantic segmentation framework is ***,the DeepLabv3+feature extraction network is replaced by the lightweight model MobileNetv2,which effectively reduces the number of model parameters;secondly,for the problem of positive and negative sample imbalance,a new loss function is composed of Focal Loss combined with Dice Loss to solve the category imbalance and improve the model discriminative ability;in addition,a more efficient atrous spatial pyramid pooling(E-ASPP)module is *** addition,a more efficient E-ASPP module is proposed,and the Roberts crossover operator is chosen to sharpen the image edges to improve the model accuracy;finally,the network structure is redesigned to further improve the model accuracy by drawing on the multi-scale feature fusion *** experimental results show that the proposed segmentation algorithm achieves an average intersection ratio of 93.45%,a precision of 94.87%,a recall of 93.65%,and a balance score of 93.64%on the PCB test set,which is more accurate than the common segmentation algorithms Hrnetv2,UNet,PSPNet,and PCBSegClassNet,and the segmentation speed is faster.

关键词： PCB boards image segmentation mobile-deep loss function roberts crossover operator

Tuning method for governor control parameters of hydropower generator in isolated grid considering primary frequency performance and small-signal stability

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Global Energy Interconnection 2018年第5期1卷 568-575页

作者： Zhenhua Xu state grid fujian Electric Power Research Institute

This paper presents a method of tuning governor control parameters of an isolated hydropower generator considering the primary frequency performance and small-signal stability. First, generators that can be operated in isolated state are identified. Second, different schemes are proposed for generator mode switching from on-grid to off-grid state through comparison and mechanism analysis. Third, the time domain model and frequency domain model of the isolated generator governor are constructed to respectively estimate the primary frequency performance and small signal stability. Parameter sets that satisfy the primary frequency performance and small signal stability are acquired as optimal values of governor control parameters. Finally, the measurement-based parameters of the governor are identified and validated using simulations to demonstrate the feasibility and effectiveness of the method.

关键词： Isolated grid Primary frequency regulation capability Small-signal stability Laplace transfer Parameter adjusting

Operational optimization of a building-level integrated energy system considering additional potential benefits of energy storage

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Protection and Control of Modern Power Systems 2021年第1期6卷 55-64页

作者： Sai Liu Cheng Zhou Haomin Guo Qingxin Shi Tiancheng E.Song Ian Schomer Yu Liu Maintenance Branch company State Grid Jiangsu Electric Power Co.Ltd.Nanjing211102Jiangsu ProvinceChina Kunshan Power Supply Branch company State Grid Jiangsu Electric Power Co.Ltd.Kunshan215300Jiangsu ProvinceChina Xiamen Power Supply company State Grid Fujian Electric Power Co.Ltd.Xiamen361004Fujian ProvinceChina Enliten Lab University of TennesseeKnoxvilleTN37996USA School of Electrical Engineering Southeast UniversityNanjing210096Jiangsu ProvinceChina

As a key component of an integrated energy system(IES),energy storage can effectively alleviate the problem of the times between energy production and *** the benefits of energy storage can improve the competitiveness of multi-energy *** paper proposes a method for day-ahead operation optimization of a building-level integrated energy system(BIES)considering additional potential benefits of energy *** on the characteristics of peak-shaving and valley-filling of energy storage,and further consideration of the changes in the system’s load and real-time electricity price,a model of additional potential benefits of energy storage is *** at the lowest total operating cost,a bi-level optimal operational model for day-ahead operation of BIES is developed.A case analysis of different dispatch strategies verifies that the addition of the proposed battery scheduling strategy improves economic *** results demonstrate that the model can exploit energy storage’s potential,further optimize the power output of BIES and reduce the economic cost.

关键词： Building-level integrated energy system Energy storage Additional potential benefits Bi-level optimization

Galvanic Corrosion Behavior of Copper-Drawn Steel for Grounding grids in the Acidic Red Soil Simulated Solution

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Acta Metallurgica Sinica(English Letters) 2020年第11期33卷 1571-1582页

作者： Xiao-Lei Fan Yun-Xiang Chen Jun-Xi Zhang De-Yuan Lin Xuan-Xuan Liu Xiao-Jian Xia Shanghai Key Laboratory of Materials Protection and Advanced Materials in Electric Power Shanghai University of Electric PowerShanghai 200090China Electric Power Research Institute of state grid fujian Electric Power company Limited Fuzhou 350007China

The influence of pH and metallographic structure on the corrosion behavior of copper-drawn steel is studied with the simulated *** effect of pH on the corrosion behavior of copper-drawn steel has been investigated using open-circuit potential,potentiodynamic polarization,galvanic current measurement,scanning electron microscopy and scanning vibrating electrode technique *** steel is corroded as anode,while the corrosion of copper plate is protected as *** the results revealed that pH and metallographic structure had a significant influence on the corrosion behavior of copper-drawn *** the decrease in pH value from 6 to 2.4,the corrosion rate of copper-drawn steel galvanic couple(Cu-Fe GC)obviously increased in the simulated solution of acidic red *** electric field formed by the Cu-Fe GC changes the direction of ion migration between the copper and drawn steel electrodes,which impacts the composition and microstructure of corrosion products formed on the electrode surface.

关键词： Cu-Fe galvanic couple Electrochemical test Scanning vibrating electrode technique(SVET)measurement Soil corrosion

Embedded Scenario Clustering for Wind and Photovoltaic Power,and Load Based on Multi-head Self-attention

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Protection and Control of Modern Power Systems 2024年第1期9卷 122-132页

作者： Lijun Liu Xin Hu Junsheng Chen Ruixing Wu Feixiong Chen School of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108China state grid Fuzhou Power Supply company fujian Smart Electrical Engineering Technology Research Center

The source and load uncertainties arising from increased applications of renewable energy sources such as wind and photovoltaic energy in the power system have had adverse effects on optimal planning and *** for generating typical renewable energy and load scenarios are constructed to reduce such effects and improve the applicability of a planning and optimal dispatching model of power systems with a high proportion of renewable *** traditional clustering-based model for representing such scenarios cannot handle high-dimensional time-series data and consequently the feature-related information obtained cannot fully reflect the characteristics of the ***,a deep convolutional embedded clustering model based on multi-head self-attention is ***,a variational mode decomposition model is optimized to reduce the influence of noise-related signals on the feature *** deep features are then extracted from the data using an improved convolutional autoencoder,and the appropriate number of clusters is determined using the elbow *** this,the network parameters are optimized based on the sum of losses during reconstruction and ***,typical scenarios are then generated based on the optimized network ***,the proposed method is evaluated based on data visualization and evaluation *** is shown that the quality of features and the accuracy of clustering can be effectively improved by the proposed scenario generation method.

关键词： handle Embedded network