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An Intrusion Detection Method for Advanced Metering Infrastructure System Based on Federated Learning

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Journal of Modern Power Systems and Clean Energy 2023年第3期11卷 927-937页

作者： Haolan Liang Dongqi Liu xiangjun zeng Chunxiao Ye School of Electrical and Information Engineering Changsha University of Science and TechnologyChangsha 410114China Hunan Institute of Engineering Xiangtan 411104China

An advanced metering infrastructure(AMI)system plays a key role in the smart grid(SG),but it is vulnerable to cyberattacks.Current detection methods for AMI cyberattacks mainly focus on the data center or a distributed independent node.On one hand,it is difficult to train an excellent detection intrusion model on a self-learning independent node.On the other hand,large amounts of data are shared over the network and uploaded to a central node for training.These processes may compromise data privacy,cause communication delay,and incur high communication costs.With these limitations,we propose an intrusion detection method for AMI system based on federated learning(FL).The intrusion detection system is deployed in the data concentrators for training,and only its model parameters are communicated to the data center.Furthermore,the data center distributes the learning to each data concentrator through aggregation and weight assignments for collaborative learning.An optimized deep neural network(DNN)is exploited for this proposed method,and extensive experiments based on the NSL-KDD dataset are carried out.From the results,this proposed method improves detection performance and reduces computation costs,communication delays,and communication overheads while guaranteeing data privacy.

关键词： Federated learning(FL) advanced metering infrastructure(AMI)system intrusion detection data concentrator

A Generalized Wind Turbine Anomaly Detection Method Based on Combined Probability Estimation Model

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现代电力系统与清洁能源学报(英文) 2023年第4期11卷 1136-1148页

作者： xiangjun zeng Ming Yang Chen Feng Yaohua Tang Key Laboratory of Power System Intelligent Dispatch and Control Shandong UniversityJinan 250061Chinaand X.Zeng is also with the College of Electrical Engineering&New EnergyChina Three Gorges UniversityYichang 443002China Rundian Energy Science and Technology Co. Ltd.Zhengzhou 450046China

Anomaly detection based on the data collected from the supervisory control and data acquisition(SCADA)system is crucial to reduce the failure rate of wind turbines(WTs).The difficulty of this kind of methods is to dynamically identify the threshold for anomaly detection under changing operating conditions.In this paper,a generalized WT anomaly detection method based on the combined probability estimation model(CPEM)is proposed.The CPEM can estimate the conditional probability density function(PDF)of the target variable given changing conditions.Its generalization and accuracy are better than those of the independent probability estimation model because it combines the advantages of various kinds of probability estimation models through linear combination.By using the CPEM,the normal operating bounds under different operating conditions can be obtained,which dynamically form the thresholds for anomaly detection.Meanwhile,with respect to the thresholds,hypothesis testing(HT)is adopted to identify the anomaly by inspecting whether the observations exceed the thresholds at a given significance level,providing sound mathematical support for anomaly detection and making the detection results more reliable.The effectiveness of the proposed method is tested by using the actual data of WTs with known faults.The results illustrate that the proposed method can detect the abnormal operating state of the gearbox and generator much more early than the system fault alarm.

关键词： Anomaly detection combined probability estimation generalization hypothesis testing(HT)

Research on Low Voltage Series Arc Fault Prediction Method Based on Multidimensional Time-Frequency Domain Characteristics

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Energy Engineering 2023年第9期120卷 1979-1990页

作者： Feiyan Zhou HuiYin Chen Luo Haixin Tong KunYu Zewen Li xiangjun zeng China Electric Power Research Institute Distribution Technology Center China Electric Power Research InstituteBeijing100192China National Key Laboratory of Disaster Prevention and Reduction for Power Grid ChangshaUniversity of Science and TechnologyChangsha410114China

The load types in low-voltage distribution systems are diverse.Some loads have current signals that are similar to series fault arcs,making it difficult to effectively detect fault arcs during their occurrence and sustained combustion,which can easily lead to serious electrical fire accidents.To address this issue,this paper establishes a fault arc prototype experimental platform,selects multiple commonly used loads for fault arc experiments,and collects data in both normal and fault states.By analyzing waveform characteristics and selecting fault discrimination feature indicators,corresponding feature values are extracted for qualitative analysis to explore changes in timefrequency characteristics of current before and after faults.Multiple features are then selected to form a multidimensional feature vector space to effectively reduce arc misjudgments and construct a fault discrimination feature database.Based on this,a fault arc hazard prediction model is built using random forests.The model’s multiple hyperparameters are simultaneously optimized through grid search,aiming tominimize node information entropy and complete model training,thereby enhancing model robustness and generalization ability.Through experimental verification,the proposed method accurately predicts and classifies fault arcs of different load types,with an average accuracy at least 1%higher than that of the commonly used fault predictionmethods compared in the paper.

关键词： Low voltage distribution systems series fault arcing grid search time-frequency characteristics

基于隧道磁电阻效应的宽频带电流无线测量装置

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电力自动化设备 2024年第4期44卷 204-210页

作者：毕岚溪曾祥君喻锟刘丰吴湘君长沙理工大学电气与信息工程学院湖南长沙410114

宽频带电气量数据包含大量故障暂态信息,传统互感器带宽受限难以精确全面地测量宽频暂态信号。针对该问题,提出一种含精确时标的非侵入式电流测量方法并设计原理样机。通过隧道磁电阻(TMR)芯片测量线路电流感生磁场,根据被测导体与TMR... 详细信息

宽频带电气量数据包含大量故障暂态信息,传统互感器带宽受限难以精确全面地测量宽频暂态信号。针对该问题,提出一种含精确时标的非侵入式电流测量方法并设计原理样机。通过隧道磁电阻(TMR)芯片测量线路电流感生磁场,根据被测导体与TMR传感器的相对位置计算变比并通过微处理器进行录波和读数。设计低噪声、可变增益的传感器模组电路和暂态录波无线测量传输模组电路,精确感知宽频信号;根据传感器实际安装位置推导传变关系式,实现对一次电流的精确计算。搭建测试平台对测量装置直流、交流及暂态信号传变能力开展测试,在10 kV配电网进行接地故障电流测量对比实验。分析了影响磁阻传感器测量精度的主要因素,结果表明其直流和工频信号测量误差小于1%,高频信号测量误差小于3%。

关键词：隧道磁电阻传感器宽频带暂态非侵入式测量

Signaling pathways in the regulation of cytokine release syndrome in human diseases and intervention therapy

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Signal Transduction and Targeted Therapy 2021年第11期6卷 3230-3245页

作者： Xia Li Mi Shao xiangjun zeng Pengxu Qian He Huang Bone Marrow Transplantation Center The First Affiliated HospitalZhejiang University School of MedicineHangzhouPeople’s Republic of China Liangzhu Laboratory Zhejiang University Medical Center1369 West Wenyi RoadHangzhou311121People’s Republic of China Institute of Hematology Zhejiang UniversityHangzhouZhejiangPeople’s Republic of China Zhejiang Province Engineering Laboratory for Stem Cell and Immunity Therapy HangzhouZhejiangPeople’s Republic of China Center of Stem Cell and Regenerative Medicine Zhejiang University School of MedicineHangzhouPeople’s Republic of China

Cytokine release syndrome(CRS)embodies a mixture of clinical manifestations,including elevated circulating cytokine levels,acute systemic inflammatory symptoms and secondary organ dysfunction,which was first described in the context of acute graft-versus-host disease after allogeneic hematopoietic stem-cell transplantation and was later observed in pandemics of influenza,SARS-CoV and COVID-19,immunotherapy of tumor,after chimeric antigen receptor T(CAR-T)therapy,and in monogenic disorders and autoimmune diseases.Particularly,severe CRS is a very significant and life-threatening complication,which is clinically characterized by persistent high fever,hyperinflammation,and severe organ dysfunction.However,CRS is a double-edged sword,which may be both helpful in controlling tumors/viruses/infections and harmful to the host.Although a high incidence and high levels of cytokines are features of CRS,the detailed kinetics and specific mechanisms of CRS in human diseases and intervention therapy remain unclear.In the present review,we have summarized the most recent advances related to the clinical features and management of CRS as well as cutting-edge technologies to elucidate the mechanisms of CRS.Considering that CRS is the major adverse event in human diseases and intervention therapy,our review delineates the characteristics,kinetics,signaling pathways,and potential mechanisms of CRS,which shows its clinical relevance for achieving both favorable efficacy and low toxicity.

关键词： cytokine release kinetics

并阻尼谐振接地系统对地参数测量与高阻故障选线新方法

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电力系统保护与控制 2024年第4期52卷 67-76页

作者：曾超喻锟曾祥君李理贺世庚贺芳煜电网防灾减灾全国重点实验室(长沙理工大学) 湖南长沙410114

针对谐振接地系统对地参数测量不准确以及高阻接地故障选线困难的问题,提出了并阻尼谐振接地系统对地参数测量与高阻故障选线新方法。基于消弧线圈并联阻尼电阻的投切特性,利用投切阻尼电阻前后零序电压幅值与相位的变化关系,测量系统... 详细信息

针对谐振接地系统对地参数测量不准确以及高阻接地故障选线困难的问题,提出了并阻尼谐振接地系统对地参数测量与高阻故障选线新方法。基于消弧线圈并联阻尼电阻的投切特性,利用投切阻尼电阻前后零序电压幅值与相位的变化关系,测量系统对地电导与电容参数。在系统正常运行时,通过调整并联阻尼电阻值大小,测量各馈线零序导纳值。在发生接地故障后退出阻尼电阻,测量故障后各馈线零序导纳值,可消除系统参数不对称、互感器采样不同步的影响,主动构造故障前后各馈线的零序导纳相角差,实现故障线路的准确判别。在PSCAD仿真环境下对所提方法进行验证,结果表明:所提方法能够精确测量对地电导与电容参数,测量相对误差不高于0.6%;在不同馈线、不同过渡电阻下发生接地故障时,能准确判别故障线路,耐过渡电阻能力达10 kΩ。

关键词：阻尼电阻谐振接地系统对地参数测量高阻故障故障选线

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利用“减心法”处理加速度关联问题

物理教学 2024年第3期46卷 62-65页

作者：曾祥军黄致新华中师范大学人工智能教育学部湖北430079 重庆市开州中学重庆405417 华中师范大学物理科学与技术学院湖北430079

文章立足于加速度关联的系列问题,通过深层次思考,全方位准确地描述了该类问题的本质。立足于物理问题的本质,作者探究出一种更简便易行的解答该类问题的方法“减心法”,便于师生对加速度关联问题的处理和把握,同时在问题的解答中彰显... 详细信息

文章立足于加速度关联的系列问题,通过深层次思考,全方位准确地描述了该类问题的本质。立足于物理问题的本质,作者探究出一种更简便易行的解答该类问题的方法“减心法”,便于师生对加速度关联问题的处理和把握,同时在问题的解答中彰显了更加深刻的物理意蕴。

关键词：加速度关联本质 “减心法”

基于改进等效电路模型的直流微电网大信号稳定性分析

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电工技术学报 2024年第5期39卷 1284-1299页

作者：王力谭振杰曾祥君赵斌郑月球长沙理工大学电气与信息工程学院长沙410114 西藏华东水电设备成套有限公司拉萨851414

对高阶非线性直流微电网进行简化建模是大信号稳定性分析的有效方法。传统简化模型主要关注LC滤波器和线路阻抗等参数,难以分析换流器控制参数的影响,所建立的判据存在难以准确反映直流微电网稳定域的问题。因此,该文提出直流电压下垂... 详细信息

对高阶非线性直流微电网进行简化建模是大信号稳定性分析的有效方法。传统简化模型主要关注LC滤波器和线路阻抗等参数,难以分析换流器控制参数的影响,所建立的判据存在难以准确反映直流微电网稳定域的问题。因此,该文提出直流电压下垂控制换流器的具备完整状态变量集的改进等效电路模型,相比于传统简化模型,能更准确地刻画系统低频响应特性。基于混合势理论推导了直流微电网大信号稳定判据及其稳定域,并结合LaSalle不变集定理得到能量指标,以反映系统稳定性变化趋势。建立的稳定判据可指导控制参数优化,且能拓展到多端直流微电网的大信号稳定性分析。在多场景下仿真验证了所提改进等效电路模型和大信号稳定判据的有效性。

关键词：直流微电网大信号稳定性等效模型直流电压控制混合势理论

A Novel Single Phase Grounding Fault Protection Scheme Without Threshold Setting for Neutral Ineffectively Earthed Power Systems

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CSEE Journal of Power and Energy Systems 2016年第3期2卷 73-81页

作者： xiangjun zeng Kun Yu Yuanyuan Wang Yao Xu Hunan Province Key Laboratory of Smart Grids Operation and Control School of Electrical&Information EngineeringChangsha University of Science and TechnologyChangsha 410076China Department of Electrical and Computer Engineering Purdue University NorthwestWestvilleIN46391USA

The setting values of thresholds for fault feature parameters are critical in all kinds of protection schemes.When the detected feature parameter value exceeds the setting value,the protection will trip.However,the setting value based conventional protection schemes sometimes cannot satisfy the protection requirements of neutral ineffectively earthed power systems(NIEPS)due to wide variations in operating conditions and the complexities of fault cases.In this paper,a novel single phase grounding fault protection scheme without threshold setting is proposed.The fault detection is achieved based on operating states rather than setting values.A fuzzy c-means algorithm is used to divide the operating state of the protected feeder into non-fault states and fault states.The cluster center of each state is then obtained by classifying the historical feature samples of the protected feeder extracted under various operating conditions into their corresponding states in a constructed multi-dimensional fault feature space.The distances between the detected feature samples and the cluster centers of the non-fault and the fault states are calculated.If the distance to the fault state is shorter than that to the non-fault state,a fault is detected.Otherwise,the feeder is considered normal.A PSCAD/EMTDC simulator is used to simulate a 35 kV NIEPS under various operating conditions,non-linear loads,and complex fault cases.Results show that the proposed single phase grounding fault protection scheme without threshold setting can protect the system correctly under all kinds of faults.

关键词： Distribution networks FCM algorithm neutral ineffectively earthed power systems protection scheme without threshold setting