Dissertation > Excellent graduate degree dissertation topics show

Analysis of the Hilbert Spectrum of Insulator Leakage Current and Abstraction of the Characteristics

Author: SunJinBao
Tutor: ZhuYongLi
School: North China Electric Power University
Course: Proceedings of the
Keywords: Leakage Current Pollution flashover Hilbert-Huang Transform Overall empirical mode decomposition (EEMD) Hilbert spectrum
CLC: TM216
Type: Master's thesis
Year: 2011
Downloads: 91
Quote: 0
Read: Download Dissertation

Abstract


The contamination flashover is the extreme result of the high voltage insulator surface discharge , a serious threat to the safe and stable operation of power systems . In order to prevent the occurrence of flashover must -depth study of the mechanism of pollution flashover accurately reveal the relationship between the leakage current pollution flashover . Fourier transform as the traditional signal analysis tools , are widely used in the analysis of the leakage current . This article does not reflect the non-stationary signal spectrum changes over time for the Fourier transform , Hilbert-Huang transform analysis tools as leakage current . View of the empirical mode decomposition (Empirical Mode Decomposition, EMD) modal aliasing , the overall paper, empirical mode decomposition (Ensemble Empirical Mode Decomposition, EEMD) to be suppressed ; combined with the characteristics of the leakage current with the data at both ends the adjacent data leakage current extension , to improve the end effect phenomenon appeared in the Hilbert-Huang Transform . Pollution flashover development of the initial phase of the leakage current waveform serious noise interference , can not accurately extract useful information . EEMD decomposition based on white noise sequence through each intrinsic mode functions (Intrinsic Mode Function, IMF) , the energy distribution of the characteristics of the two denoising method based on EEMD wavelet thresholding denoising Comparisons its effectiveness . The study showed that the two denoising method in noise intensity is not at the same time each with advantages , appropriate denoising method can be selected according to the noise intensity . This paper follows the development of pollution flashover process thinking leakage current 3 section , the leakage current is divided into several sections , and analysis of the time-domain waveform of the leakage current of each section and Hilbert spectrum . Hilbert spectrum based on intrinsic mode energy leakage current than the intrinsic mode energy entropy -based the Hilbert spectrum band energy than the changes in the whole process of pollution flashover . The studies show that the leakage current inherent modal energy than the intrinsic mode energy entropy and based on the the Hilbert spectrum band energy than can be better to describe the development of flashover , as the amount of leakage current characteristics for the early warning of pollution flashover provide clearer theoretical guidance .

Related Dissertations

  1. Research on Feature Extraction and Classification of Doppler Ultrasonic Blood Flow Signals of Wrist Radial Artery,TP391.41
  2. Based on the DC leakage current research insulator flashover,TM216
  3. The Research on the Examination and Failure Diagnosis for Leakage Current of Insulator on the Power Line,TM216
  4. EMD-based speaker recognition,TN912.34
  5. Weather Statistics Filthy and Dirty Flash Design and Application of Early Warning,TM216
  6. Study on East China Grid Transmission Line Insulator Saturated Contamination (Salt Density) the Characteristic and Outside Insulates Configuration Method,TM216
  7. Study on Electric Field Distribution Optimization of Composite Insulator with Series Connection of Glass Insulator,TM216
  8. Study on Dynamic Contamination Deposit on the Suspension Insulators of Power Transmission Line,TM852
  9. Study of Secondary Arc Current in UHV Transmission Lines and the Influence to the Auto Reclosing,TM762.2
  10. Improvements of the power spectrum based on Hilbert-Huang extract pulsatile displacement of the vessel wall,TN911.7
  11. Intelligent Fault Diagnosis of Rotating Machine Based on Hilbert Spectrum and Novelty Detection,TH165.3
  12. Study on the Low Frequency Signal Anchor Bolt of Dynamic Response Charateristics,TD353.6
  13. Research of the Effect Factor on Insulation Leakage Current,TM216
  14. Study on Electrical Transport and Breakdown Characteristics of GaN-based Schottky Barrier Diodes,TN311.7
  15. HHT array acoustic signal processing,P631.81
  16. MSP430-based real-time monitoring system for network equipment,TM76
  17. Feature Extraction of Frequency-Varying Components Based on Hilbert-Huang Transform,U666.7
  18. The Study of Interaction between Shroud Cavity Flow and Main Flow in an Axial Gas Turbine,TK261
  19. Influence of Cement Pollution on the Hydrophobicity Transfer and Pollution Flashover Properties of Silicone Rubber Composite Insulators,TM216
  20. Based on Grey System Theory helicopter rotor fault diagnosis,V267.4

CLC: > Industrial Technology > Electrotechnical > Electrical materials > Insulating materials,dielectric,and its products > Insulator and casing
© 2012 www.DissertationTopic.Net  Mobile