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Swin-Transformer故障信息挖掘的海底观测网故障定位方法
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作者 栾韶泽 李光炬 +3 位作者 甘维明 季桂花 邢炜光 赵赞善 《网络新媒体技术》 2024年第3期47-56,共10页
海底观测网长期受海洋环境与人为因素影响,易使光电复合缆绝缘破损与海水接触形成电学故障点。如何准确地定位电学故障点,对提高海底观测网输电与信息传输的可靠性至关重要。首先根据海底观测网输电结构建立海底观测网输电模型,推导与... 海底观测网长期受海洋环境与人为因素影响,易使光电复合缆绝缘破损与海水接触形成电学故障点。如何准确地定位电学故障点,对提高海底观测网输电与信息传输的可靠性至关重要。首先根据海底观测网输电结构建立海底观测网输电模型,推导与模拟电学故障点传播至观测点的暂态电流,然后由连续小波变换提取暂态电流与故障点对应的内在关联特征量,最后通过Swin-Transformer神经网络挖掘内在关联特征量与故障距离的匹配关系来定位电学故障点。研究结果表明,在内在关联特征量样本测试集条件下,光电复合缆≤160 km的电学故障点定位误差小于400 m,可为长距离光电复合缆的海底观测网电学故障点定位提供参考。 展开更多
关键词 海底观测网 光电复合缆 电学故障点 暂态电流 Swin-transformer 故障点定位
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Transformer Internal and Inrush Current Fault Detection Using Machine Learning
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作者 R.Vidhya P.Vanaja Ranjan N.R.Shanker 《Intelligent Automation & Soft Computing》 SCIE 2023年第4期153-168,共16页
Preventive maintenance in the transformer is performed through a dif-ferential relay protection system,and it protects the transformer from internal and external faults.However,the Current Transformer(CT)in the differ... Preventive maintenance in the transformer is performed through a dif-ferential relay protection system,and it protects the transformer from internal and external faults.However,the Current Transformer(CT)in the differential protec-tion system mal-operates during inrush currents.CT saturates due to magnetizing inrush currents and causes false tripping of the differential relays.Moreover,iden-tification of tripping in protection relay either due to inrush current or internal faults needs to be diagnosed.For the above problem,continuous monitoring of transformer breather and CT terminals with thermal camera helps detect the trip-ping in relay due to inrush or internal fault.The transformer’s internal fault leads to high breathing process in the transformer breather,never for inrush currents.During inrush currents,CT temperature is increased.Continuous monitoring of breather and CT of the transformer through thermal imaging and radiometric pix-els detect the causes of CT saturation and differentiates maloperation.Hybrid wavelet threshold image analytics(HWT-IA)based radiometric pixels analysis of the transformer breather and CT after de-noising provides an accurate result of about 95%for identification of the false tripping of differential protection system of transformer. 展开更多
关键词 WAVELET THRESHOLD inrush transformer BREATHER current transformer thermal image
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SIMULATING METHOD OF MAGNETIZING INRUSH CURRENT OF POWER TRANSFORMERS USING CONCEPT OF INSTANTANEOUS POWER
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作者 贺家李 段玉倩 《Transactions of Tianjin University》 EI CAS 1999年第1期1-6,共6页
In this paper,a new simulating method is presented,using only the normal magnetizing curve (B-H) of the transformer core material,its geometric dimensions,the no-load power loss data and the concept of instantaneous p... In this paper,a new simulating method is presented,using only the normal magnetizing curve (B-H) of the transformer core material,its geometric dimensions,the no-load power loss data and the concept of instantaneous power. At the end of this paper the simulating calculation using EMTP has been also performed for the same transformer. The comparison shows that the two sets of results are very close to each other,and proves the correctness of the new method. The new method presented in this paper is helpful to verify the correctness of the power transformer design,analyze the behavior of the transformer protection under switching and study the new transformer protection principles. 展开更多
关键词 power transformer magnetizing inrush current remnant flue
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Effect of Modulation Error on All Optical Fiber Current Transformers 被引量:3
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作者 Zhengping Wang Yuekun Wang Shuai Sun 《Journal of Sensor Technology》 2012年第4期172-176,共5页
For actively modulated In-line Sagnac interferential all optic fiber current transformers (AOFCTs), the accuracies are directly affected by the amplitude of the modulation signal. In order to deeply undertand the func... For actively modulated In-line Sagnac interferential all optic fiber current transformers (AOFCTs), the accuracies are directly affected by the amplitude of the modulation signal. In order to deeply undertand the function of the modulator, a theoretical model of modulation effect to AOFCTs is built up in this paper. The effect of the amplitude of the modulation signal to the output intensity of AOFCTs is theoretically formulated and numerical calculated. The results show that the modulation voltage variation could affect the output accuracies significantly. This might be some references on the investigation for practical applications of AOFCTs. 展开更多
关键词 Electronic current transformer All Optical FIBER current transformer Faraday EFFECT Active MODULATION MODULATION ERROR
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Study of wavelet transform type high-current transformer 被引量:2
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作者 卢文科 朱长纯 +1 位作者 刘君华 张建军 《Journal of Coal Science & Engineering(China)》 2002年第2期75-79,共5页
The wavelet transformation is applied to the high current transformer.The high current transformer elaborated in the paper is mainly applied to the measurement of AC/DC high current.The principle of the transformer is... The wavelet transformation is applied to the high current transformer.The high current transformer elaborated in the paper is mainly applied to the measurement of AC/DC high current.The principle of the transformer is the Hall direct measurement principle.The transformer has the following three characteristics:firstly, the effect of the remnant field of the iron core on the measurement is decreased;secondly,because the temperature compensation is adopted,the transformer has good temperature charactreristic;thirdly,be cause the wavelet transfomation technology is adopted,the transformer has the capacity of good antijanming. 展开更多
关键词 wavelet transformation high current SENSOR Hall direct measurement transformer
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Design and applicability analysis of independent double acquisition circuit of all-fiber optical current transformer 被引量:2
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作者 Songlin Gu Liu Han +3 位作者 Dongwei Liu Wenbin Yu Zhihong Xiao Teng Feng 《Global Energy Interconnection》 2019年第6期532-541,共10页
The advantages of the all-fiber optical current transformer include but are not limited to being small in size,having no magnetic saturation,exhibiting high measurement accuracy,and boasting strong electromagnetic int... The advantages of the all-fiber optical current transformer include but are not limited to being small in size,having no magnetic saturation,exhibiting high measurement accuracy,and boasting strong electromagnetic interference resistance.However,the high cost of the all-fiber optical transformer limits its promotion and application in engineering.This paper proposes a design scheme of an independent double acquisition loop for the all-fiber optical current transformer based on the single optical path.Firstly,based on the closed-loop control mode and open-loop control mode,the twochannel sampling signal demand for relay protection,and the independent dual-acquisition loop design scheme of the all-fiber optical current transformer are proposed.Secondly,the reliability and economic feasibility of the scheme are demonstrated by an analysis of system failure and cost.The results show that the scheme can actualize the acquisition function of two independent all-fiber optical current transformer products on a single all-fiber current transformer in an integrated manner,which greatly reduces the cost of the all-fiber optical current transformer in engineering applications. 展开更多
关键词 All-fiber optical current transformer Acquisition circuit RELIABILITY
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Optically Driven Current Transformer with Optical Fiber Data Link 被引量:1
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作者 YAO Ling-shi 《Semiconductor Photonics and Technology》 CAS 2000年第3期151-155,164,173,共7页
An optical fiber transmitting photoelectric coupling current transformer has been developed. In the environment of high voltage and electromagnetic fields, this device is characterized by high insulation, high reliabi... An optical fiber transmitting photoelectric coupling current transformer has been developed. In the environment of high voltage and electromagnetic fields, this device is characterized by high insulation, high reliability, small mass and high anti-interference. The structure design and operating principle of the system are introduced, measurement errors are analyzed and experimental results are given. 展开更多
关键词 Optical fiber transmission current transformer DETECTOR
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Over Voltage Fault due to Disconnection of Consumer’s Transformer Neutral Wire
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作者 Erdene Adiyasuren Enkh-Od Erdene +1 位作者 Sergelen Byambaa Shagdarsuren Gantumur 《Journal of Energy and Power Engineering》 2023年第1期11-14,共4页
Practically,the load currents in three phases are asymmetric in the power system.It means that the impedances are different in all three phases.If the consumer’s transformer neutral cut off and/or was disconnected fr... Practically,the load currents in three phases are asymmetric in the power system.It means that the impedances are different in all three phases.If the consumer’s transformer neutral cut off and/or was disconnected from the neutral of power supply source,then there will be some trouble and failure occurred.The current in the neutral wire drops down to zero when the neutral wire is cut off and the phase currents of all three-phase equal to each other since there was no return wire.The currents are equal but the voltages at the phase consumers are different.Especially for residential single-phase consumers,the voltage at the consumers of the phase varies differently for three phase systems when the neutral wire was disconnected at consumer side and even the voltage at the consumers one or two of those three phases becomes over nominal voltage or reaches nearly line voltage.In this case,the electronic appliances in that phase will be fed by high voltage than the rated value and they can be broken down.In the power system of UB(Ulaanbaatar)city,there are some occasional such kind of failures every year.Obviously,many electronic appliances were broken down due to high voltage and the electricity utility companies respond for service charge of damaged parts. 展开更多
关键词 Neutral connection and neutral wire phase and line voltage single-phase residential consumer transformer neutral cut off asymmetric load current protective earth
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Transforming growth factor-beta 1 enhances discharge activity of cortical neurons
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作者 Zhihui Ren Tian Li +5 位作者 Xueer Liu Zelin Zhang Xiaoxuan Chen Weiqiang Chen Kangsheng Li Jiangtao Sheng 《Neural Regeneration Research》 SCIE CAS 2025年第2期548-556,共9页
Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may de... Transforming growth factor-beta 1(TGF-β1)has been extensively studied for its pleiotropic effects on central nervous system diseases.The neuroprotective or neurotoxic effects of TGF-β1 in specific brain areas may depend on the pathological process and cell types involved.Voltage-gated sodium channels(VGSCs)are essential ion channels for the generation of action potentials in neurons,and are involved in various neuroexcitation-related diseases.However,the effects of TGF-β1 on the functional properties of VGSCs and firing properties in cortical neurons remain unclear.In this study,we investigated the effects of TGF-β1 on VGSC function and firing properties in primary cortical neurons from mice.We found that TGF-β1 increased VGSC current density in a dose-and time-dependent manner,which was attributable to the upregulation of Nav1.3 expression.Increased VGSC current density and Nav1.3 expression were significantly abolished by preincubation with inhibitors of mitogen-activated protein kinase kinase(PD98059),p38 mitogen-activated protein kinase(SB203580),and Jun NH2-terminal kinase 1/2 inhibitor(SP600125).Interestingly,TGF-β1 significantly increased the firing threshold of action potentials but did not change their firing rate in cortical neurons.These findings suggest that TGF-β1 can increase Nav1.3 expression through activation of the ERK1/2-JNK-MAPK pathway,which leads to a decrease in the firing threshold of action potentials in cortical neurons under pathological conditions.Thus,this contributes to the occurrence and progression of neuroexcitatory-related diseases of the central nervous system. 展开更多
关键词 central nervous system cortical neurons ERK firing properties JNK Nav1.3 p38 transforming growth factor-beta 1 traumatic brain injury voltage-gated sodium currents
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An active-passive beam current transformer 被引量:1
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作者 ZHOU Wei SUN Baogen LU Ping WANG Xiaohui WANG Yong ZHANG Haiyan 《Nuclear Science and Techniques》 SCIE CAS CSCD 2008年第2期70-73,共4页
In this article,a new type current transformer was developed using an active-passive circuit to improve low frequency response of the system without impairing high frequency response.The active-passive current transfo... In this article,a new type current transformer was developed using an active-passive circuit to improve low frequency response of the system without impairing high frequency response.The active-passive current transformer with In-flange was fabricated.Theoretical analysis,numerical simulations and experimental results are given. 展开更多
关键词 电流 变压器 电路 频率反应
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Alternative Approaches for Distinguishing between Faults and Inrush Current in Power Transformers
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作者 Ahmed M. A. Alomar Bakr E. M. Shamseldin 《Energy and Power Engineering》 2014年第7期143-160,共18页
In this study, we will cover the basic methods used to distinguish between inrush current and fault current in power transformers. First, the nature of inrush current is presented compared to the fault current. Then t... In this study, we will cover the basic methods used to distinguish between inrush current and fault current in power transformers. First, the nature of inrush current is presented compared to the fault current. Then the nature of the magnetizing current due to energizing a power transformer at no-load is explained. The first generation of methods used to disable the protective relay system during inrush current, namely the Desensitizing and Tripping Suppressor, is introduced. The second generation, the harmonic restraint method and the waveform-based restraint method with their different versions, is explained. Then we will explore thoroughly the fictitious equivalent resistance method as an example of the third generation of model type restraining or blocking methods. Finally, a comparison between these methods and conclusion is carried out. 展开更多
关键词 Power transformer Inrush current DIFFERENTIAL RELAY
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The Discrimination of Inrush Current from Internal Fault of Power Transformer based on EMD
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作者 Fanyuan Zeng Qianjin Liu Chao Shi 《Energy and Power Engineering》 2013年第4期1425-1428,共4页
The method is based on that the waveform of the inrush distorts seriously, while the fault current nearly keeps sinusoid. The complicated signal can be decomposed into a finite intrinsic mode functions (IMF) by the EM... The method is based on that the waveform of the inrush distorts seriously, while the fault current nearly keeps sinusoid. The complicated signal can be decomposed into a finite intrinsic mode functions (IMF) by the EMD, then define and compute the projection area on X-axis of each IMF—, the specific gravity of SIMF—, and the maximum of —. We can get a new scheme of transformer-protection based on comparing the difference between inrush and fault current. Theoretical analysis show that the method can precisely discriminate inrush and fault current, fault clearance time is about 20ms. Moreover, it is convenient to achieve and hardly be affect by not-periodic component. 展开更多
关键词 Inrush current transformer PROTECTION HHT EMD IMF
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Analysis on the Transfer Characteristics of Rogowski-coil Current Transformer and Its Influence on Protective Relaying
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作者 Yi Wang Jiaman Li +3 位作者 Yulan Hu Ranran An Zexiang Cai Ruiwen He 《Energy and Power Engineering》 2013年第4期1324-1329,共6页
This paper systematically analyzes the transfer characteristics of the Rogowski-coil Current Transformer and its effect on protective relaying through theoretical analysis, experiments and simulations. The frequency c... This paper systematically analyzes the transfer characteristics of the Rogowski-coil Current Transformer and its effect on protective relaying through theoretical analysis, experiments and simulations. The frequency characteristics and transient characteristics of Rogowski transducer and Rogowski-coil Current Transformer are deeply analyzed based on the physical structure of the transformer.?It is revealed that broad bandwidth of the transformer can improve the performance of protective relaying, and the bandwidth is determined mainly by the parameters of the Rogowski transducer and signal processing circuits. It is also discovered that the measurement errors of transient current mainly depend on the abilities for the current transformer to reproduce an accurate replica of the decaying dc components, which is mainly decided by the decay time constant of the aperiodic component of transient current and the parameters of the integral unit. Finally, some measures are proposed for the performance improvement of Rogowski-coil Current Transformer to meet the requirements of protective relaying system in terms of structural design and testing standards. 展开更多
关键词 current transformer Rogowski-coil TRANSFER Characteristics Protective RELAYING
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Optical fiber-based power and data delivery system for high voltage electronic current transformer
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作者 邱红辉 段雄英 邹积岩 《Journal of Shanghai University(English Edition)》 CAS 2008年第3期268-273,共6页
This paper describes a prototype power delivery system developed for high voltage electronic current transformer (ECT) that uses laser light to transfer power to and communicates with the primary converter. The desi... This paper describes a prototype power delivery system developed for high voltage electronic current transformer (ECT) that uses laser light to transfer power to and communicates with the primary converter. The design is based on optical-to-electrical power converters, solid-state diode lasers and optical fibers. Command signals are transmitted via the same up-fiber used to send power from secondary power supply to primary converter. The upward data transmission is completed during the brief interruption of power delivery without affecting steady power-supply. A simple comparator added to the primary converter can take the command data. Experimental results show that the fibers can provide reliable up-link for data transmission at 200 kb/s from the secondary to the primary converter. Based on the delivery system, the secondary converter can control three auxiliary channels to provide additional information. These monitoring channels are used in a time-multiplexing mode to provide information about the operation temperature, voltage and current at the remote unit for monitoring the ECT. This preventive maintenance or built-in test can increase reliability by giving early warning for necessary maintenance request. 展开更多
关键词 high voltage electronic current transformer (ECT) optical power supply delivery system photovoltaic powerconverters supervisory functions
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Investigation and Mitigation of Transformer Inrush Current during Black Start of an Independent Power Producer Plant
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作者 Salman Kahrobaee Marcelo C. Algrain Sohrab Asgarpoor 《Energy and Power Engineering》 2013年第1期1-7,共7页
The energizing of large power transformers has long been considered a critical event in the operation of an electric power system. When a transformer is energized by the utility, a typical inrush current could be as h... The energizing of large power transformers has long been considered a critical event in the operation of an electric power system. When a transformer is energized by the utility, a typical inrush current could be as high as ten times its rated current. This could cause many problems from mechanical stress on transformer windings to harmonics injection, and system protection malfunction. There have been numerous researches focusing on calculation and mitigation of the transformer inrush current. With the development of smart grid, distributed generation from independent power producers (IPPs) is growing rapidly. This paper investigates the inrush current due to black start of an IPP system with several parallel transformers, through a simulation model in DIgSILENT Power Factory software. The study demonstrates that a single genset is capable of energizing a group of transformers since the overall inrush current is slightly above the inrush of the transformer directly connected to the generator. In addition, a simple method is proposed to mitigate the inrush current of the transformers using an auxiliary transformer. 展开更多
关键词 BLACK START Distributed Generation Inrush current MITIGATION INDEPENDENT Power PRODUCER transformer Energizing
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Calculation of Eddy Current Loss and Short-circuit Force in SSZ11-50000/110 Power Transformer
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作者 Yan Li Bo Zhang +2 位作者 Longnv Li Tongxun Yang Ning Wang 《Energy and Power Engineering》 2013年第4期1105-1108,共4页
The ?method is used in this paper to calculate the leakage magnetic field of SSZ11-50000/110 Power transformer, and by which the structures’ influences to the main leakage flux are analyzed. Through the combination o... The ?method is used in this paper to calculate the leakage magnetic field of SSZ11-50000/110 Power transformer, and by which the structures’ influences to the main leakage flux are analyzed. Through the combination of the product and TEAM Problem 21B, the surface impedance method shows its great advantage in the calculation of eddy current loss. 展开更多
关键词 Power transformer FINITE Element SHORT-CIRCUIT FORCE EDDY current LOSS Surface IMPEDANCE Method
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Study on the Effect of Multi-Type Current Transformers Hybrid Operation on Differential Protection of the Bus Based on Dynamic Simulation
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作者 Wenbiao Liao Zexin Zhou +2 位作者 Rongrong Zhan Yanjun Li Zhengguang Chen 《Energy and Power Engineering》 2017年第4期1-11,共11页
This paper analyzes characteristics of multi type current transformers hybrid operation for each branch of the bus and their effects on differential protection of the bus. By theoretically analyzing transmission chara... This paper analyzes characteristics of multi type current transformers hybrid operation for each branch of the bus and their effects on differential protection of the bus. By theoretically analyzing transmission characteristics of multi type current transformers and their influence factors, we study the dynamic model testing method of multi type current transformers for the bus, and design 3 kinds of testing schemes by making the equivalent model based on the field of P-level current transformer, TPY-level current transformer and electronic current transformer, and build the hybrid operation testing platform of multi type current transformers. Finally, we compare and analyze the transmission characteristics difference of multi type current transformers on the same branch and the characteristics difference of hybrid operation in two successive external faults, analyze the cause behind the differences, and put forward the corresponding improvement measures. 展开更多
关键词 DIFFERENTIAL Protection of the BUS Multi-Type current transformer Hybrid Operation DYNAMIC SIMULATION TEST Method DYNAMIC SIMULATION TEST Platform
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Analysis and suppression method of transformer no-load closing excitation inrush current
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作者 Li Zhengming Chen Yuchen Wang Chengmin 《International English Education Research》 2014年第12期97-99,共3页
The primary winding of the transformer will generate large inrush current due to the saturation of iron core when an unloaded transformer is switched-on. The inrush current not only causes mechanical interaction force... The primary winding of the transformer will generate large inrush current due to the saturation of iron core when an unloaded transformer is switched-on. The inrush current not only causes mechanical interaction force due to which the windings are damaged, but also induces the differential protection relays to operate incorrectly. In this paper, the mathematical model of unloaded single phase transformer in switch-on is analyzed; the computation formulas of the inrush current and its interruption angle are presented. The experiment investigation of single phase transformers with different capacities shows that the inrush current measurement result is consistent with theoretical analysis. The inrush current waveform is typically a steeple top waveform with high order harmonics and damping in one direction. In the same condition, large inrush current amplitude will be induced with smaller switching angle, larger residual flux and smaller saturation flux. 展开更多
关键词 transformer Magnetizing impedance Magnetizing inrush current Unload switched-on
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APPLICATION OF NEURAL NETWORK FOR THE TRANSFORMER PROTECTIVE RELAYS
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作者 李永丽 顾福海 +1 位作者 刘志华 贺家李 《Transactions of Tianjin University》 EI CAS 1998年第2期11-14,共4页
A neural network method used to identify the different operating states of transformers has been proposed and established.It is superior to the traditional transformer protective principles and can correctly identify,... A neural network method used to identify the different operating states of transformers has been proposed and established.It is superior to the traditional transformer protective principles and can correctly identify,within half cycle from the fault inception,the internal faults,magnetizing inrush current state,external faults and switching on the internal faults of a no load transformer.In addition,this method has broad availability and high fault tolerant ability.A lot of simulations have demonstrated its superiority. 展开更多
关键词 neural network inrush current fault identification transformer
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A novel shapelet transformation method for classification of multivariate time series with dynamic discriminative subsequence and application in anode current signals 被引量:3
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作者 WAN Xiao-xue CHEN Xiao-fang +2 位作者 GUI Wei-hua YUE Wei-chao XIE Yong-fang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第1期114-131,共18页
Classification of multi-dimension time series(MTS) plays an important role in knowledge discovery of time series. Many methods for MTS classification have been presented. However, most of these methods did not conside... Classification of multi-dimension time series(MTS) plays an important role in knowledge discovery of time series. Many methods for MTS classification have been presented. However, most of these methods did not consider the kind of MTS whose discriminative subsequence was not restricted to one dimension and dynamic. In order to solve the above problem, a method to extract new features with extended shapelet transformation is proposed in this study. First, key features is extracted to replace k shapelets to calculate distance, which are extracted from candidate shapelets with one class for all dimensions. Second, feature of similarity numbers as a new feature is proposed to enhance the reliability of classification. Third, because of the time-consuming searching and clustering of shapelets, distance matrix is used to reduce the computing complexity. Experiments are carried out on public dataset and the results illustrate the effectiveness of the proposed method. Moreover, anode current signals(ACS) in the aluminum reduction cell are the aforementioned MTS, and the proposed method is successfully applied to the classification of ACS. 展开更多
关键词 anode current signals key features distance matrix feature of similarity numbers shapelet transformation
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