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ANN based pattern recognition of partial discharge in power transformer 被引量:1
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作者 王哲 蔡惟铮 陈学允 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1999年第4期82-85,共4页
Expounds a partial discharge detection circuit and a microcomputer based partial discharge monitoring system. The importance of statistical phase position distribution of partial discharge events for failure diagnosi... Expounds a partial discharge detection circuit and a microcomputer based partial discharge monitoring system. The importance of statistical phase position distribution of partial discharge events for failure diagnosis of power transformer and discusses an artificial neural network trained with φ q patterns for pattern recognition of partial discharge is discussed in detail, which is proved to be effective for on line monitoring. 展开更多
关键词 partial discharge (pd) artificial neural network (ANN) fast FOURIER TRANSFORM (FFT)
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Application of Complex Daubechies Wavelet in UHF Partial Discharge Measurements 被引量:3
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作者 XIE Yan-bin TANG Ju ZHANG Xiao-xing 《高电压技术》 EI CAS CSCD 北大核心 2008年第12期2701-2707,共7页
On-line partial discharge(PD)detection still remains a very challenging task because of the strong electromagnetic interferences.In this paper,a new method of de-noising,using complex Daubechies wavelet(CDW)transform,... On-line partial discharge(PD)detection still remains a very challenging task because of the strong electromagnetic interferences.In this paper,a new method of de-noising,using complex Daubechies wavelet(CDW)transform,has been proposed.It is a relatively recent enhancement to the real-valued wavelet transform because of tow important properties,which are nearly shift-invariant and availability of phase information.Those properties give CDW transform superiority over other real-valued wavelet transform,and then the construction algorithm of CDW is introduced in detail.Secondly,based on the real threshold algorithm of real-valued wavelet transform,complex threshold algorithm is devised.This algorithm take the different characteristics of real part and imaginary part of complex wavelet coefficients into account,it modifies the real and imaginary parts of complex wavelet coefficients respectively.Thirdly,to obtain a real de-noised signal,new combined information series is devised.By applying different combination of real part and imaginary part of de-noised complex signal,a real de-noised signal can be restored with higher peak signal-to-noise ratio(PSNR)and less distortion of original signals.Finally,On-site applications of extracting PD signals from noisy background by the optimal de-noising scheme based on CDW are illustrated.The on-site experimental results show that the optimal de-noising scheme is an effective way to suppress white noise in PD measurement. 展开更多
关键词 Db复小波 超高频 局部放电 测量 CDW
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Development and Application of DC Partial Discharge Test System 被引量:2
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作者 NIE Dexin SHA Yanchao +2 位作者 ZHOU Yuanxiang WU Zhirong DENG Jiangang 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期1981-1987,共7页
Direct current (DC) partial discharge (PD) test has drawn extensive attention from world-wide electric power research institutes in recent years. However, presently, no DC PD detection device on the market has the sta... Direct current (DC) partial discharge (PD) test has drawn extensive attention from world-wide electric power research institutes in recent years. However, presently, no DC PD detection device on the market has the statistical function. Thus, we developed a test system for PD detection under DC voltage, which is characterized by strong anti-jamming capability, continuous high-speed real-time data acquisi- tion and effective, complete detection of DC PD signals. The DC PD mechanism, as well as the measuring principles, software system, and hardware design of the test equipment were introduced. Adopting typical electrode pairs, we tested the statistical spectrum of PD under DC voltage. The main difference in statistical spectrums between parallel plate electrodes and needle-plate electrodes was that the time interval between two consecutive discharges for needle-plate electrodes has obviously larger variation range than that for parallel plate electrodes, which could be the convincing proof for distinguishing the type of electrodes under DC PD. Practical results indicate that the proposed sys- tem can measure time domain signals of DC PD of oil-paper insulation effectively and promptly, and it can be used to determine and detect defects in DC power transmission equipment. 展开更多
关键词 局部放电信号 直流电压 测试系统 开发 针板电极 应用 检测装置 实时数据采集
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Wavelet packet decomposition entropy threshold method for discrete spectrum interferences rejection of on-line partial discharge monitoring
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作者 唐炬 SUN Caixin +1 位作者 SONG Shengli LI Jian 《Journal of Chongqing University》 CAS 2003年第1期9-12,共4页
The frequency domain division theory of dyadic wavelet decomposition and wavelet packet decomposition (WPD) with orthogonal wavelet base frame are presented. The WPD coefficients of signals are treated as the outputs ... The frequency domain division theory of dyadic wavelet decomposition and wavelet packet decomposition (WPD) with orthogonal wavelet base frame are presented. The WPD coefficients of signals are treated as the outputs of equivalent bandwidth filters with different center frequency. The corresponding WPD entropy values of coefficients increase sharply when the discrete spectrum interferences (DSIs), frequency spectrum of which is centered at several frequency points existing in some frequency region. Based on WPD, an entropy threshold method (ETM) is put forward, in which entropy is used to determine whether partial discharge (PD) signals are interfered by DSIs. Simulation and real data processing demonstrate that ETM works with good efficiency, without pre-knowing DSI information. ETM extracts the phase of PD pulses accurately and can calibrate the quantity of single type discharge. 展开更多
关键词 partial discharge(pd) discrete spectrum interference(DSI) wavelet packet decomposition(Wpd) ENTROPY
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Long Distance GIL PD Fault Localization Method Based on Amplitude Difference and Time Difference Calculation of UHF Coupling Signal
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作者 Zhang Hui Hu Po Tao Ke 《Journal of Mechanics Engineering and Automation》 2016年第1期39-46,共8页
In the long distance GIL under certain conditions, this paper researches and realizes detection of PD characters and accurate fault localization through UHF coupling sensors at different positions of the GIL pipeline.... In the long distance GIL under certain conditions, this paper researches and realizes detection of PD characters and accurate fault localization through UHF coupling sensors at different positions of the GIL pipeline. The main methods for the detection are UHF signal amplitude difference (DOA) and time difference (TOF). We analyze the localization error by using TE and TEM component and high order TE mode component in electromagnetic coaxial wave guide theory. Research and field test prove the DOA detection error can meet the requirements of real-time online diagnosis and for history tracking analysis. The error of TOF detection method can be controlled within 3% and can be applied to the site. 展开更多
关键词 GIL partial discharge UHF EM-wave amplitude difference time difference fault localization.
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Partial Discharge Simulations Used for the Design of a Non-Intrusive Cable Condition Monitoring Technique
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作者 Heino van Jaarsveldt Rupert Gouws 《Journal of Energy and Power Engineering》 2013年第11期2193-2201,共9页
The purpose of this paper is to investigate the effect of PD (partial discharge) activity within medium voltage XLPE (cross-linked polyethylene) cables. The effect of partial discharge was studied by means of a nu... The purpose of this paper is to investigate the effect of PD (partial discharge) activity within medium voltage XLPE (cross-linked polyethylene) cables. The effect of partial discharge was studied by means of a number of simulations. The simulations were based on the well-known three capacitor model for partial discharge. An equivalent circuit was derived for partial discharge due to a single void in the insulation material of a power cable. The results obtained from the simulations will form the basis of the design proses of a non-intrusive condition monitoring technique. The technique is based on the classification of discharge activity according to five levels of PD. Future work will include the improvement of the simulation model by investigating the high frequency model of a power cable as well as the statistical nature of PD activity. This will improve the accuracy of the simulation results when compared to actual measurements. The work discussed in this paper will be used to construct and calibrate a practical model which will make use of PD measurements for non-intrusive condition monitoring of medium voltage electrical cables. 展开更多
关键词 Condition monitoring non-intrusive pd partial discharge XLPE (cross-linked polyethylene) void size apparentcharge.
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基于移动FFT的PD在线检测中正弦干扰抑制方法 被引量:7
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作者 白建社 陈丹 +2 位作者 王成多 徐政 关长毅 《电力系统及其自动化学报》 CSCD 北大核心 2007年第6期118-123,共6页
为剔除局部放电在线检测中干扰信号,尤其是连续正弦干扰(continuous sine interference,CSI),应用移动(fast Fourier transform,FFT)算法,以递推的方式求取信号的离散傅里叶变换(discrete Fouriertransform,DFT),提高信号处理的实时性... 为剔除局部放电在线检测中干扰信号,尤其是连续正弦干扰(continuous sine interference,CSI),应用移动(fast Fourier transform,FFT)算法,以递推的方式求取信号的离散傅里叶变换(discrete Fouriertransform,DFT),提高信号处理的实时性。通过对频域信号进行阈值处理,来抑制局部放电测量中的CSI干扰,并通过离散傅里叶反变换(inverse discrete Fourier transform,IDFT)获得处理结果。另外,每次提取处理结果的中间数据(大小等于步长)作为本步的处理结果,避免了DFT的边沿效应和窗函数的影响。实验结果表明,所提出的方法能够很好地滤除局部放电中的连续正弦干扰,且使局部放电脉冲衰减很小,实时性好。将该方法应用于地铁牵引变电站馈线电缆绝缘性能的在线检测中,取得良好的效果。 展开更多
关键词 移动快速傅里叶变换 连续正弦干扰 局部放电 自适应滤波
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融合形态学-复小波变换的PD干扰信号抑制方法 被引量:4
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作者 王有元 张大伟 +1 位作者 陆国俊 黄炎光 《仪器仪表学报》 EI CAS CSCD 北大核心 2013年第3期707-713,共7页
针对局部放电检测过程中周期性窄带干扰和白噪声难以抑制的问题,提出了一种融合数学形态学与复小波变换的干扰信号抑制方法。该方法基于数学形态学原理构造广义形态学滤波器,并将其作为前置滤波单元,实现原始信号的预处理,再对处理后的... 针对局部放电检测过程中周期性窄带干扰和白噪声难以抑制的问题,提出了一种融合数学形态学与复小波变换的干扰信号抑制方法。该方法基于数学形态学原理构造广义形态学滤波器,并将其作为前置滤波单元,实现原始信号的预处理,再对处理后的信号进行复小波变换,最终得到去噪后的局部放电信号。应用该方法对模拟和现场采集的局部放电信号进行去噪处理,结果表明:该方法能够有效地抑制局部放电信号中的周期性窄带干扰和白噪声干扰;与相同小波基的小波去噪方法和复小波去噪方法相比,该方法去噪时的能量损失较小,能够很好地保留局部放电信号特征。 展开更多
关键词 局部放电 窄带干扰 白噪声 数学形态学 复小波变换 抑制方法
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BPD型变频电源用于局放和耐压试验的研究与实践 被引量:3
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作者 程盛 李卫东 《高压电器》 EI CAS CSCD 北大核心 2007年第2期146-148,共3页
介绍了某供电公司对主变局放和谐振耐压试验电源的研究和选用思路,简要介绍了局放和耐压试验现场实施情况,证实了BPD型变频电源不仅可以用于GIS及电缆等大容量设备的谐振耐压试验,而且可以用于变压器的局部放电试验。
关键词 变频电源 谐振 局部放电 耐压试验
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基于竞争子网络的数字滤波法在PD在线监测中的应用
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作者 王哲 蔡惟铮 陈学允 《电力系统自动化》 EI CSCD 北大核心 1999年第10期32-34,60,共4页
介绍了竞争子网络的工作原理和结构 ,提出基于竞争子网络邻抑制作用的数字滤波法 ,并将该方法运用于局部放电在线监测系统的抑制通信干扰的滤波环节中。实践证明这种方法具有自适应性强、通信干扰抑制效果好、运算速度快等优点。
关键词 数字滤波 局部放电 在线监测 高压电器设备
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检波技术在超高频PD信号提取中的应用研究 被引量:8
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作者 蒋庆云 张重远 +1 位作者 刘云鹏 律方成 《华北电力大学学报(自然科学版)》 CAS 北大核心 2006年第3期10-13,共4页
介绍了包络检波技术的基本原理及其在超高频局部放电信号提取中的应用,分析了影响信号检波失真的主要因素,设计了用于超高频局部放电检测的检波电路并进行了计算机MATLAB仿真。计算机仿真验证了在超高频局部放电信号提取中,应用包络检... 介绍了包络检波技术的基本原理及其在超高频局部放电信号提取中的应用,分析了影响信号检波失真的主要因素,设计了用于超高频局部放电检测的检波电路并进行了计算机MATLAB仿真。计算机仿真验证了在超高频局部放电信号提取中,应用包络检波技术可降低检测系统的采样频率并保留放电信号的峰值和相位特征。仿真结果表明,应用包络检波技术提取超高频局部放电信号是可行的。 展开更多
关键词 局部放电 超高频 包络检波技术
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大型电机PD信号的在线检测与处理 被引量:1
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作者 谢自美 陈乔夫 《华中理工大学学报》 CSCD 北大核心 1995年第4期64-68,共5页
提出了一种大型电机PD信号在线检测的方法,即以STD总线工业控制机为下位机进行PD信号的检测,以IBM-PC机为上位机进行数据处理,通过上下机通信实现PD信号的自动检测与处理。实验证明,用该方法实现的PD信号在线检测... 提出了一种大型电机PD信号在线检测的方法,即以STD总线工业控制机为下位机进行PD信号的检测,以IBM-PC机为上位机进行数据处理,通过上下机通信实现PD信号的自动检测与处理。实验证明,用该方法实现的PD信号在线检测装置抗干扰能力较强,检测到的PD信号波形与理论分析结论相吻合。 展开更多
关键词 大型 电机 在线检测 pd信号 故障 电机
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大型电机PD信号的数字滤波研究
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作者 谢自美 黄利 陈建聪 《华中理工大学学报》 CSCD 北大核心 1996年第2期89-91,共3页
以大型电机PD信号的数字滤波为背景,介绍了一种基于窗函数法的FIR数字滤波器设计方法.对大型电机离线和在线检测的PD信号的实验研究表明,应用该方法设计的PD信号数字带通滤波器,其通频带越宽,阶数越高,滤波效果越好,适... 以大型电机PD信号的数字滤波为背景,介绍了一种基于窗函数法的FIR数字滤波器设计方法.对大型电机离线和在线检测的PD信号的实验研究表明,应用该方法设计的PD信号数字带通滤波器,其通频带越宽,阶数越高,滤波效果越好,适用于在工频噪声干扰环境下提取较弱的PD信号. 展开更多
关键词 电机 局部放电 数字滤波器 pd信号 窗函数法
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Analysis of Excitation Characteristics of Ultra High Frequency Electromagnetic Waves Induced by PD in GIS 被引量:7
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作者 DING Dengwei GAO Wensheng +2 位作者 YAO Senjing LIU Weidong HE Jiaxi 《高电压技术》 EI CAS CSCD 北大核心 2013年第8期1893-1901,共9页
The understanding of the excitation mechanism of ultra high frequency (UHF) electromagnetic waves (EW) is essential for ap- plying UHF method to partial discharge (PD) detection. Since the EW induced by PD in gas insu... The understanding of the excitation mechanism of ultra high frequency (UHF) electromagnetic waves (EW) is essential for ap- plying UHF method to partial discharge (PD) detection. Since the EW induced by PD in gas insulated switchgear (GIS) contains not only transverse electromagnetic (TEM) wave, but also high-order transverse electric (TE) and high-order transverse magnetic (TM) waves, we analyzed the proportions between the TEM wave and the high order waves, as well as the influence of the PD position on this proportion, using the finite different time domain (FDTD) method. According to the unique characteristics of the waves, they are separated only ap- proximately. It is found that the high-order mode is the main component, more than 70%, of the electric field around the enclosure of GIS, and that with the increasing distance between PD source and inner conductors, the low frequency ( below about 800 MHz) component of EW decreases, but the high frequency component (above 1 GHz) increases, meanwhile the proportion of high-order components in EW could reach 77% from 70%. It concluded that the closer the PD source to the enclosure is, the easier high order EW may be excited. 展开更多
关键词 超高频电磁波 励磁特性 GIS pd 诱导 气体绝缘开关设备 UHF方法 TEM波
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Experiments on Corona Discharge Under AC and DC Composite Voltage 被引量:1
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作者 ZHU Zhengyi LI Ruihai +3 位作者 WANG Guoli CHEN Can JIA Zhidong GUAN Zhicheng 《高电压技术》 EI CAS CSCD 北大核心 2012年第8期2001-2007,共7页
关键词 局部放电 射频信号 放电量 高电压技术
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一起应用PD Monitor检测开关柜局放的分析和处理 被引量:1
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作者 余力行 《电工技术》 2018年第10期54-55,58,共3页
为加强对金属封闭开关柜的带电检测工作,通过检测仪器PD Monitor局部放电定位仪对一起开关柜内部放电定位。主要介绍了一起由套管内壁母排与套管屏蔽环间等电位磷铜片面放电引起的暂态地电压超标的现象。
关键词 pd MONITOR 开关柜 局放放电
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Experimental Evaluation of Rogowski Coil Performance for Locating PD in Energized Overhead Covered-Conductor Feeder
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作者 Muzamir Isa Nagy Ibrahim Elkalashy +1 位作者 Ghulam Murtaza Hashmi Matti Lehtonen 《Journal of Energy and Power Engineering》 2012年第6期949-959,共11页
An experimental analysis is performed to evaluate Rogowski coil performance for PD (partial discharge) location on overhead CC (covered-conductor) distribution lines. The measuring set-up is arranged in high volta... An experimental analysis is performed to evaluate Rogowski coil performance for PD (partial discharge) location on overhead CC (covered-conductor) distribution lines. The measuring set-up is arranged in high voltage laboratory. A multi-end measuring method is chosen as a technique to locate PD source point on the line. A power transformer is used to energize one end of the CC line by the AC voltage source. The performance of Rogowski-coil is tested in noisy environment. The tests are carried out conceming different measurement conditions such as off-line and on-line PD measuring systems. The results obtained from the laboratory measurements confirm the capability of the Rogowski-coil in order to measure and locate the high frequency PD source on the CC line in consistent with energizing AC source. Chirp detector is used as a signal-processing tool in order to extract the PD signals and then apply the locator algorithm. 展开更多
关键词 partial discharge Rogowski coil overhead covered-conductor distribution network pd sensors.
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GIS绝缘子金属污秽缺陷不同程度间歇性放电诊断分析研究 被引量:1
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作者 黄立才 杨旭 +3 位作者 张静 罗传仙 陈佳 张国治 《电气传动》 2024年第2期88-96,共9页
针对现场气体绝缘组合电器(GIS)绝缘缺陷局部放电漏报、误报情况频发的问题,利用真型GIS搭建局放多源检测试验平台,开展绝缘子表面金属污秽缺陷间歇性放电试验,采用不同局放检测法研究不同程度间歇性放电特性变化规律。研究结果表明:金... 针对现场气体绝缘组合电器(GIS)绝缘缺陷局部放电漏报、误报情况频发的问题,利用真型GIS搭建局放多源检测试验平台,开展绝缘子表面金属污秽缺陷间歇性放电试验,采用不同局放检测法研究不同程度间歇性放电特性变化规律。研究结果表明:金属污秽缺陷放电量随着放电时间的延长呈现先升后降的变化趋势;放电时间间隔整体呈现增加的变化趋势;超声检测法和化学检测法无法实现金属污秽间歇性放电的有效感知;由4组50个工频周期特高频(UHF)相位分辨局部放电(PRPD)图谱数据所构成的200个工频周期UHF PRPD图谱中能初步得出间歇性放电分布规律;处于间歇性放电状态的金属污秽缺陷不会逐渐发展演变成击穿放电故障。研究成果对拓展间歇性放电特征的认知及现场对GIS放电缺陷的检测具有重要意义。 展开更多
关键词 气体绝缘组合电器 金属污秽 间歇性 局部放电 多源特征
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基于改进小波阈值—CEEMDAN的变压器局部放电超声波信号白噪声抑制方法 被引量:7
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作者 周晶 罗日成 黄军 《高压电器》 CAS CSCD 北大核心 2024年第1期163-171,共9页
为了有效去除变压器局部放电超声信号中的白噪声干扰,提高后续局部放电模式识别及定位的准确性,提出了一种基于改进小波阈值和自适应噪声完全集合经验模态分解(complete ensemble empirical mode decomposition with adaptive noise,CEE... 为了有效去除变压器局部放电超声信号中的白噪声干扰,提高后续局部放电模式识别及定位的准确性,提出了一种基于改进小波阈值和自适应噪声完全集合经验模态分解(complete ensemble empirical mode decomposition with adaptive noise,CEEMDAN)的变压器局部放电超声波信号去噪方法。首先,通过对放电信号进行CEEMDAN分解得到一系列由高频到低频的本征模函数IMF(intrinsic mode function);然后,利用多尺度排列熵(multi-scale permutation entropy,MPE)算法计算各阶IMF分量的排列熵PE(permutation entropy),根据各IMF的排列熵值确定信号的去噪阈值与有效阈值。对高于去噪阈值的IMF分量采用改进小波阈值法进行去噪处理,对低于有效阈值的IMF分量视为基线漂移进行剔除。最后,通过重构去噪分量与剩余分量来获得去噪后的超声波信号。仿真和实验结果均表明,文中所提出的去噪算法大大提高了信号的信噪比,并保留了原始超声波信号中的有效信息,对提高后续利用超声波信号进行局部放电模式识别及定位的精确性具有重要意义。 展开更多
关键词 局部放电 超声波信号去噪 改进小波阈值 多尺度排列熵 CEEMDAN
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基于自适应模拟退火优化算法的集合式电容器局放定位研究 被引量:1
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作者 李欢 国江 +2 位作者 陶维亮 杨欣婷 罗可心 《电子设计工程》 2024年第7期139-143,共5页
集合式电容器内部局部放电问题可能导致绝缘介质破坏和设备故障。已有的局部放电检测技术在集合式电容器中受到电磁干扰的限制。为此,提出了一种自适应模拟退火粒子群超声定位方法。该方法结合超声检测法克服电磁干扰对定位精度的影响,... 集合式电容器内部局部放电问题可能导致绝缘介质破坏和设备故障。已有的局部放电检测技术在集合式电容器中受到电磁干扰的限制。为此,提出了一种自适应模拟退火粒子群超声定位方法。该方法结合超声检测法克服电磁干扰对定位精度的影响,通过对粒子群参数进行自适应优化,并应用模拟退火和轮盘赌策略进行优化。为检测该方法的效果,通过对比实验表明,该方法提高了定位的准确性和稳定性,为集合式电容器局部放电定位问题提供了有效的解决方案。 展开更多
关键词 集合式电容器 局部放电定位 超声检测 粒子群算法
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