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微电网HHT谐波检测与时频分析方法 被引量:11
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作者 关维国 姚清志 鲁宝春 《计算机工程与应用》 CSCD 北大核心 2015年第20期198-202,212,共6页
为解决微电网谐波、突变等复杂非平稳信号的精确检测问题,提出一种基于Hilbert-Huang变换(HHT)的微电网谐波检测与时频分析方法。该方法采用保形分段三次埃尔米特插值法拟合极值点曲线,对谐波信号进行经验模态分解(EMD),得到有限个固有... 为解决微电网谐波、突变等复杂非平稳信号的精确检测问题,提出一种基于Hilbert-Huang变换(HHT)的微电网谐波检测与时频分析方法。该方法采用保形分段三次埃尔米特插值法拟合极值点曲线,对谐波信号进行经验模态分解(EMD),得到有限个固有模态分量(IMF)并进行Hilbert变换,最终计算各个IMF分量的瞬时频率和瞬时幅值,实现微电网谐波等非平稳电能信号的时频特性精确检测。仿真结果表明,该方法能够快速、准确地获取谐波信号频率成分、幅度及电压突变时刻。相对于FFT变换及传统HHT方法具有较高的精度和时域区分特性,可满足微电网谐波微机检测的工程应用需求。 展开更多
关键词 微电网 谐波检测 希尔伯特-黄变换(hht) 经验模态分解 瞬时频率 Hilbert-Huang Transform(hht)
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Optimization of the End Effect of Hilbert-Huang transform(HHT) 被引量:4
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作者 Chenhuan Lv Jun ZHAO +2 位作者 Chao WU Tiantai GUO Hongjiang CHEN 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第3期732-745,共14页
In fault diagnosis of rotating machinery, Hil- bert-Huang transform (HHT) is often used to extract the fault characteristic signal and analyze decomposition results in time-frequency domain. However, end effect occu... In fault diagnosis of rotating machinery, Hil- bert-Huang transform (HHT) is often used to extract the fault characteristic signal and analyze decomposition results in time-frequency domain. However, end effect occurs in HHT, which leads to a series of problems such as modal aliasing and false IMF (Intrinsic Mode Func- tion). To counter such problems in HHT, a new method is put forward to process signal by combining the general- ized regression neural network (GRNN) with the bound- ary local characteristic-scale continuation (BLCC). Firstly, the improved EMD (Empirical Mode Decompo- sition) method is used to inhibit the end effect problem that appeared in conventional EMD. Secondly, the gen- erated IMF components are used in HHT. Simulation and measurement experiment for the cases of time domain, frequency domain and related parameters of Hilbert- Huang spectrum show that the method described here can restrain the end effect compared with the results obtained through mirror continuation, as the absolute percentage of the maximum mean of the beginning end point offset and the terminal point offset are reduced from 30.113% and 27.603% to 0.510% and 6.039% respectively, thus reducing the modal aliasing, and eliminating the false IMF components of HHT. The proposed method caneffectively inhibit end effect, reduce modal aliasing and false IMF components, and show the real structure of signal components accuratelX. 展开更多
关键词 End effect Hilbert-Huang transform hht)Modal aliasing Boundary local characteristic-scalecontinuation (BLCC) Generalized regression neuralnetwork (GRNN)
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Improved HHT and its application in narrowband radar imaging for precession cone-shaped targets 被引量:2
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作者 Shen Zhao Jie Niu +1 位作者 Xiang Li Chunjie Qiao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第6期977-986,共10页
Imaging the spatial precession cone-shaped targets with narrowband radar is a new technical approach in mid-course recognition problem. However, most existing time-frequency methods still have some inevitable deficien... Imaging the spatial precession cone-shaped targets with narrowband radar is a new technical approach in mid-course recognition problem. However, most existing time-frequency methods still have some inevitable deficiencies for extracting microDoppler information in practical applications, which leads to blurring of the image. A new narrowband radar imaging algorithm for the precession cone-shaped targets is proposed. The instantaneous frequency of each scattering point is gained by using the improved Hilbert-Huang transform, then the positions of scattering points in the parameter domain are reconstructed. Numerical simulation and experiment results confirm the effectiveness and high precision of the proposed algorithm. 展开更多
关键词 improved Hilbert-Huang transform(hht instanta-neous frequency narrowband radar imaging precession cone-shaped targets
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Pulse Wave Analysis in Patients with Coronary Heart Disease Based on Hilbert-Huang Transformation and Time-domain 被引量:4
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作者 LI Fu-feng WANG Yi-qin +3 位作者 SUN Ren XUE Song YAO Di SHEN Hai-dong 《Chinese Journal of Biomedical Engineering(English Edition)》 2013年第2期47-54,共8页
Objective: To study the characteristics of pulse tracings in CHD, and objectively evaluate the significance of pulse signal in diagnosis and appreciation of therapeutic effect in patients with coronary heart disease(C... Objective: To study the characteristics of pulse tracings in CHD, and objectively evaluate the significance of pulse signal in diagnosis and appreciation of therapeutic effect in patients with coronary heart disease(CHD), and accordingly provide with theoretic proofs for developing non-invasive technique of pulse diagnosis. Methods: By using the pulse detection system, pulse graphs in CHD patients, patients without CHD and "health" adults were collected and compared. Then characters of the pulse signal were analyzed with Hilbert-Huang transformation routine (HHT) and time-domain method respectively. Results: There existed characteristic change in pulse graph in CHD. ① h1,h3,h4,h3/h1,t,t5/t4 in time domain parameters of pulse graph increased and w1 was widened. ② 44% of C2 wave in HHT display showed chaotic and disorderly wave and irregularly wave amplitude in CHD. And 72% of C5 Wave exhibited in irregular wave with average wave amplitude over 10 gram-forces. These changes were significantly different from health adults. Conclusion: Characteristic wave of pulse graph extracted with methods of time domain or HHT routine might be considered as proofs for diagnosis and differentiation in CHD. Our researches prognosticate that pulse diagnosis can be used as an ancillary determination in occurrence of CHD for reasons of the advantage of convenient operation and non-invasion. 展开更多
关键词 coronary heart disease(CHD) pulse graph Hilbert-Huang transformation(hht) time-domain method
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基于HHT方法的三水站月均流量序列的多时间尺度分析 被引量:1
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作者 钱海强 《广东水利水电》 2011年第5期32-33,36,共3页
应用基于经验模态分解(EMD)的Hilbert-Huang Transform(HHT)方法对珠江三角洲网河区顶端三水水文站1960~2009年的月均流量序列进行多时间尺度分析,结果表明:网河区顶端三水站的月均流量具有明显的年内(0.27~0.58a)、年际(平均周期1.1... 应用基于经验模态分解(EMD)的Hilbert-Huang Transform(HHT)方法对珠江三角洲网河区顶端三水水文站1960~2009年的月均流量序列进行多时间尺度分析,结果表明:网河区顶端三水站的月均流量具有明显的年内(0.27~0.58a)、年际(平均周期1.16a)、多年(2.38~5.00a)和年代际(10.00~25.00a)周期变化,并且以年内的周期波动最为重要;2010~2015年三水站来水量呈上升趋势。 展开更多
关键词 三水站 Hilbert-Huang Transform(hht)方法 月均流量
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基于小波去噪与HHT的隔膜泵主轴故障诊断研究 被引量:1
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作者 印嘉 《装备制造技术》 2015年第5期138-140,共3页
往复式活塞隔膜泵的主轴的运行状况的好坏,直接影响着隔膜泵的正常运行,乃至整个管道输送系统的有效运行。提出一种基于小波去噪与HHT相结合的往复式活塞隔膜泵主轴故障诊断方法。先采用小波变换对原始振动信号进行去噪,再对去噪后的振... 往复式活塞隔膜泵的主轴的运行状况的好坏,直接影响着隔膜泵的正常运行,乃至整个管道输送系统的有效运行。提出一种基于小波去噪与HHT相结合的往复式活塞隔膜泵主轴故障诊断方法。先采用小波变换对原始振动信号进行去噪,再对去噪后的振动信号进行HHT处理,可以得到HHT边际谱,最后通过分析HHT边际谱,实现了对设备故障有效的诊断和研究。实验表明,通过基于小波去噪与HHT的方法对往复式隔膜泵主轴的故障诊断是有效的和可行的。 展开更多
关键词 往复式隔膜泵 主轴 小波去噪 Hilbert-Huang Transform(hht) 边际谱 故障诊断
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Efficacy of Hilbert-Huang Transform (HHT) in the Analysis of Instantaneous Low Frequency Waves of Magnetosheath
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作者 Ekong U. Nathaniel Nyakno J. George +1 位作者 Jewel I. Ibanga Aniekan M. Ekanem 《International Journal of Geosciences》 2016年第1期11-19,共9页
The flow of supersonic plasma is accompanied by a highly thermalized region called the Magnetoshealth found after the bow shock. Enclosed within this region are different wave modes associated with classes of boundari... The flow of supersonic plasma is accompanied by a highly thermalized region called the Magnetoshealth found after the bow shock. Enclosed within this region are different wave modes associated with classes of boundaries which have been determined by different methods. The efficacy of Hilbert-Huang transform (HHT) is based on the conditionality of allowing for the local analysis of frequencies, which presents the physical meaning of the original signal at that instant. The observed data have been taken from Cluster II Fluxgate Magnetometer (FGM) instrument that provides advantage for the analysis in three dimensions. The result compares favourably with instantaneous frequencies computed using simple Hilbert transform (SHT) with electric field measurements of Cluster II mission already carried out in literatures. The result of this study has shown that HHT provides the best applicability in the magnetosheath data analysis than the wavelet and Fast Fourier Transform (FFT). The application of HHT based on its advantages over other methods is viewed to be very critical in the analysis of multi-frequency signals where different frequencies could be determined distinctively at a point. 展开更多
关键词 Plasma Waves Instantaneous Frequency Empirical Mode Decomposition (EMD) Hilbert-Huang Transform (hht)
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Efficacy of Hilbert-Huang Transform (HHT) in the Analysis of Instantaneous Low Frequency Waves of Magnetosheath
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作者 Ekong U. Nathaniel Nyakno J. George +1 位作者 Jewel I. Ibanga Aniekan M. Ekanem 《International Journal of Geosciences》 2016年第1期11-19,共9页
The flow of supersonic plasma is accompanied by a highly thermalized region called the Magnetoshealth found after the bow shock. Enclosed within this region are different wave modes associated with classes of boundari... The flow of supersonic plasma is accompanied by a highly thermalized region called the Magnetoshealth found after the bow shock. Enclosed within this region are different wave modes associated with classes of boundaries which have been determined by different methods. The efficacy of Hilbert-Huang transform (HHT) is based on the conditionality of allowing for the local analysis of frequencies, which presents the physical meaning of the original signal at that instant. The observed data have been taken from Cluster II Fluxgate Magnetometer (FGM) instrument that provides advantage for the analysis in three dimensions. The result compares favourably with instantaneous frequencies computed using simple Hilbert transform (SHT) with electric field measurements of Cluster II mission already carried out in literatures. The result of this study has shown that HHT provides the best applicability in the magnetosheath data analysis than the wavelet and Fast Fourier Transform (FFT). The application of HHT based on its advantages over other methods is viewed to be very critical in the analysis of multi-frequency signals where different frequencies could be determined distinctively at a point. 展开更多
关键词 Plasma Waves Instantaneous Frequency Empirical Mode Decomposition (EMD) Hilbert-Huang Transform (hht)
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基于希尔伯特-黄变换的远区爆破振动信号能量演化及分布规律 被引量:7
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作者 唐旭 邹飞 方正峰 《科学技术与工程》 北大核心 2016年第30期47-51,91,共6页
基于HHT分析法,对远区爆破振动信号进行时频分析。研究信号中能量随爆源距增加的演化及分布规律。结果表明:爆破振动总能量及峰值能量随着爆源距的增加衰减较快;低频段能量在传播过程中会随爆源距增加有增大的趋势;而中高频能量则是随... 基于HHT分析法,对远区爆破振动信号进行时频分析。研究信号中能量随爆源距增加的演化及分布规律。结果表明:爆破振动总能量及峰值能量随着爆源距的增加衰减较快;低频段能量在传播过程中会随爆源距增加有增大的趋势;而中高频能量则是随着爆源距的增加有减小的趋势。同时,爆源距对远区爆破振动的频率段构成也会造成影响,即频率左右限均有减小的趋势;但频带宽度总体保持不变。考虑爆破振动信号所携带的能量信息在爆破振动设计方案的优化中同样具有重大的工程意义。 展开更多
关键词 尔伯特-黄变换(Hilben-Huang transformation hht) 爆破振动能量 能量集中频段 各频段能量分布
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Practical implementation of Hilbert-Huang Transform algorithm 被引量:35
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作者 黄大吉 赵进平 苏纪兰 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2003年第1期1-14,共14页
Hilbert-Huang Transform (HHT) is a newly developed powerful method for nonlinear and non-stationary time series analysis. The empirical mode decomposition is the key part of HHT, while its algorithm was protected by N... Hilbert-Huang Transform (HHT) is a newly developed powerful method for nonlinear and non-stationary time series analysis. The empirical mode decomposition is the key part of HHT, while its algorithm was protected by NASA as a US patent, which limits the wide application among the scientific community. Two approaches, mirror periodic and extrema extending methods, have been developed for handling the end effects of empirical mode decomposition. The implementation of the HHT is realized in detail to widen the application. The detailed comparison of the results from two methods with that from Huang et al. (1998, 1999), and the comparison between two methods are presented. Generally, both methods reproduce faithful results as those of Huang et al. For mirror periodic method (MPM), the data are extended once forever. Ideally, it is a way for handling the end effects of the HHT, especially for the signal that has symmetric waveform. The extrema extending method (EEM) behaves as good as MPM, and it is better than MPM for the signal that has strong asymmetric waveform. However, it has to perform extrema envelope extending in every shifting process. 展开更多
关键词 Hilbert-Huang Transform (hht) signal processing Empirical Mode Decomposition (EMD)
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Pulse-to-pulse periodic signal sorting features and feature extraction in radar emitter pulse sequences 被引量:5
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作者 Qiang Guo Zhenshen Qu Changhong Wang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2010年第3期382-389,共8页
A novel class of periodically changing features hidden in radar pulse sequence environment,named G features,is proposed.Combining fractal theory and Hilbert-Huang transform,the features are extracted using changing ch... A novel class of periodically changing features hidden in radar pulse sequence environment,named G features,is proposed.Combining fractal theory and Hilbert-Huang transform,the features are extracted using changing characteristics of pulse parameters in radar emitter signals.The features can be applied in modern complex electronic warfare environment to address the issue of signal sorting when radar emitter pulse signal parameters severely or even completely overlap.Experiment results show that the proposed feature class and feature extraction method can discriminate periodically changing pulse sequence signal sorting features from radar pulse signal flow with complex variant features,therefore provide a new methodology for signal sorting. 展开更多
关键词 signal sorting fractal geometry Hilbert-Huang transform(hht) G feature extraction.
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GPS station short-term dynamic characteristics of micro displacement before Menyuan M6.4 earthquake 被引量:5
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作者 Wei Feng Jinwei Ren Zaisen Jiang 《Geodesy and Geodynamics》 2016年第4期237-244,共8页
Continuous observation data from 24 GPS stations are selected in the area (33.0°N-41.0°N, 95.0°E-105.0°E) for this study (the period is from Jan. 1, 2015 to Jan. 20, 2016). Three components, NS... Continuous observation data from 24 GPS stations are selected in the area (33.0°N-41.0°N, 95.0°E-105.0°E) for this study (the period is from Jan. 1, 2015 to Jan. 20, 2016). Three components, NS, EW and UD, of the daily solutions are filtered by the Hilbert-Huang transform (HHT) with frequency band of 5.787×10^-7-7.716 ×10^-8 Hz (20-150 days in period). And short-term dynamic characteristics of micro displacement before Menyuan M6.4 earthquake are studied by using the temporal dependencies and cross spectrum analysis. The results show that before the earthquake the horizontal undulatory motions are higher than the average level in the series data which indicate the disturbance feature of regional stress before the earthquake. Three GPS stations on Qinghai-Tibet Plateau with their setting perpendicular to the seismogenic fault have consistent movement. The increase of amplitude of the horizontal micro motion observed before the quake is conducive to the earthquake occurrence. However, we could not be sure if the undulatory motion triggered the earthquake. It is quite necessary to build more GPS continuous observation stations and optimize the monitoring network so as to improve the understanding of the shortterm dynamic crustal variation before earthquake. 展开更多
关键词 Menyuan earthquake Global positioning system (GPS) Undulatory motion Hilbert-Huang transform hht Cross spectrum
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Analysis of sEMG signal for KOA classification 被引量:1
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作者 李玉榕 廖志伟 杜民 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2011年第6期113-119,共7页
The sEMG signals are collected from the vastus lateralis,vastus medialis,biceps femoris,and semitendinosus of lower extremity during level walking among control subjects and knee osteoarthritis (OA) patients,the latte... The sEMG signals are collected from the vastus lateralis,vastus medialis,biceps femoris,and semitendinosus of lower extremity during level walking among control subjects and knee osteoarthritis (OA) patients,the latter including mild,moderate and severe degree.The 5-fold cross-validation is used to measure the accuracy of the proposed analysis algorithm on collected sEMG recordings.For comparison,the more classical feature vectors of form factor,degree of skewness,kurtosis,and wavelet entropy are also tested.In experiment,the normalized energy ratio and marginal spectrum ratio achieve larger accuracy than the other features for all the four muscular groups.Moreover the accuracy of vastus medialis and biceps femoris are larger than that of vastus lateralis and semitendinosus.These results suggest that the normalized energy ratio and marginal spectrum ratio via the analysis of knee sEMG signals by HHT can server as characteristic parameters to easily classify osteoarthritis with noninvasive method.The more important muscular groups for maintaining the knee joint function are medialis and biceps femoris;as a result of that they should be exercise especially for rehabilitation. 展开更多
关键词 osteoarthritis (OA) noninvasive diagnosis surface electromyography (sEMG) Hilbert-Huang Transform (hht) neural network classifier
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Hilbert spectrum and intrinsic oscillation mode of dynamic response of a bilinear SDOF system: influence of harmonic excitation amplitude 被引量:1
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作者 张郁山 梁建文 胡聿贤 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2005年第1期17-26,共10页
Under harmonic wave excitation, the dynamic response of a bilinear SDOF system can be expressed by the Hilbert spectrum. The Hilbert spectrum can be formulated by (1) the inter-wave combination mechanism between the s... Under harmonic wave excitation, the dynamic response of a bilinear SDOF system can be expressed by the Hilbert spectrum. The Hilbert spectrum can be formulated by (1) the inter-wave combination mechanism between the steady response and the transient response when the system behaves linearly, or (2) the intra-wave modulation mechanism embedded in one intrinsic mode function (IMF) component when the system behaves nonlinearly. The temporal variation of the instantaneous frequency of the IMF component is consistent with the system nonlinear behavior of yielding and unloading. As a thorough study of this fundamental structural dynamics problem, this article investigates the influence of the amplitude of the harmonic wave excitation on the Hilbert spectrum and the intrinsic oscillatory mode of the dynamic response of a bilinear SDOF system. 展开更多
关键词 bilinear SDOF system Hilbert-Huang transform (hht) Hilbert spectrum Hilbert marginal spectrum Fourier spectrum intrinsic mode function (IMF) intra-wave modulation inter-wave combination
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Analysis of the characteristics of gastrointestinal motility based on Hilbert-Huang transform method 被引量:1
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作者 黄标 Yan Guozheng 《High Technology Letters》 EI CAS 2008年第1期30-34,共5页
Pressure activity data as an important index of gastrointestinal (GI) motility can be obtained from the wireless radiotelemetry capsule. The Hilbert-Huang transform (HHT) method, which is more effective to process... Pressure activity data as an important index of gastrointestinal (GI) motility can be obtained from the wireless radiotelemetry capsule. The Hilbert-Huang transform (HHT) method, which is more effective to process non-stationary signal, is proposed to identify the characteristics of GI motility. We decompose the pressure activity data into intrinsic mode functions (IMFs), calculate the Hi/bert marginal spectrum and attain the peristalsis characteristics of GI tract. The IMFs represent the peristalses modes of GI tract activity embedded in the pressure data. The time-varying characteristic of the method suggests that the HHT is suitable to accommodate other non-stationary biomedical data analysis. 展开更多
关键词 intrinsic mode function empirical mode decomposition (EMD) Hilbert-Huang transform hht method gastrointestinal (GI) motility
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Diagnosis of stator faults in induction motor based on zero sequence voltage after switch-off
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作者 Jia-qiang YANG Jin HUANG Tong LIU 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2008年第2期165-172,共8页
To improve the accuracy of the stator winding fault diagnosis in induction motor,a new diagnostic method based on the Hilbert-Huang transform(HHT)was proposed.The ratio of fundamental zero sequence voltage to positive... To improve the accuracy of the stator winding fault diagnosis in induction motor,a new diagnostic method based on the Hilbert-Huang transform(HHT)was proposed.The ratio of fundamental zero sequence voltage to positive sequence voltage after switch-off was selected as the stator fault characteristic,which could effectively avoid the influence of the supply unbalance and the load fluctuation,and directly represent the asymmetry in the stator.Using the empirical mode decomposition(EMD)based on HHT,the zero sequence voltage after switch-off was decomposed and the fundamental component was extracted.Then,the fault characteristic can be acquired.Experimental results on a 4-kW induction motor demonstrate the feasibility and effectiveness of this method. 展开更多
关键词 Induction motor Stator fault diagnosis Hilbert-Huang transform hht Zero sequence voltage Empirical modedecomposition (EMD)
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Rotor broken-bar fault diagnosis of induction motor based on HHT of the startup electromagnetic torque
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作者 NIU Fa-liang HUANG Jin +2 位作者 YANG Jia-qiang CHEN Li-yuan JIN Hai 《Frontiers of Electrical and Electronic Engineering in China》 CSCD 2006年第2期188-193,共6页
This paper presents a new method for rotor broken-bar fault diagnosis of induction motors.The asymmetry of the rotor caused by broken-bar fault will give rise to the appearance of additional frequency component of 2 s... This paper presents a new method for rotor broken-bar fault diagnosis of induction motors.The asymmetry of the rotor caused by broken-bar fault will give rise to the appearance of additional frequency component of 2 s sf(s is slip and s f is supply frequency)in the electromagnetic torque spectrum.The startup electromagnetic torque signal is decomposed into several intrinsic mode function(IMF)with empirical mode decomposition(EMD)based on the Hilbert-Huang Transform.Then,using the instantaneous frequency extraction principle of the Hilbert Transform,the rotor broken-bar fault characteristic frequency of 2 s sf can be exactly extracted from the IMF component,which includes the rotor fault information.Moreover,the magnitude of the IMF which includes the rotor fault information can also give the number of rotor broken bars.Experimental results demonstrate that the proposed electromagnetic torque-based fault diagnosis method is feasible. 展开更多
关键词 Electromagnetic torque Fault diagnosis Induction motor Hilbert-Huang transform(hht)
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SV波作用下刚性挡土墙地震主动土压力时频域计算方法 被引量:5
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作者 杨长卫 张建经 +2 位作者 付晓 杜林 唐雅蕾 《岩石力学与工程学报》 EI CAS CSCD 北大核心 2014年第3期615-622,共8页
基于弹性波动理论,概化刚性挡土墙的动力分析模型,利用水平分层法,建立单元体的受力平衡微分方程,借助Hilbert-Huang变换,提出地震作用下刚性挡土墙地震主动土压力的时频域计算方法,并通过与振动台试验结果的对比验证该方法的合理性。... 基于弹性波动理论,概化刚性挡土墙的动力分析模型,利用水平分层法,建立单元体的受力平衡微分方程,借助Hilbert-Huang变换,提出地震作用下刚性挡土墙地震主动土压力的时频域计算方法,并通过与振动台试验结果的对比验证该方法的合理性。分析输入波频率对刚性挡土墙墙后填土的临界破裂角、地震主动土压力合力以及作用点的影响,结果表明:随着地震烈度的增大,临界破裂角逐渐减小,地震主动土压力合力逐渐增大,合力作用点位置略有上移;随着输入波频率的增大,临界破裂角和地震主动土压力合力分别呈"倒马鞍型"和"正马鞍形"分布,并且均在输入波频率与刚性挡土墙系统自振频率相近时达到最大,而地震主动土压力合力的作用点则基本上不变;按照现有规范不考虑输入波频率进行刚性挡土墙地震稳定性设计,可能会降低挡墙的地震安全储备。刚性挡土墙地震主动土压力的时频域计算方法不仅能够考虑地震波三要素(峰值、频率以及持时)对挡墙土压力的影响,同时也能够为其他类型支挡结构的抗震时频设计提供一定的参考。 展开更多
关键词 土力学 刚性挡土墙 地震主动土压力 HILBERT-HUANG变换 时频分析法 Hilbert-Huang transform(hht)
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