Dissertation > Excellent graduate degree dissertation topics show

The Research of Transformer Differential Protection Based on Wavelet Transforms

Author: LiuJianHui
Tutor: DuanYuBo
School: Daqing Petroleum Institute
Course: Power Electronics and Power Drives
Keywords: Wavelet Transform Singularity Transformer differential protection Magnetizing inrush
CLC: TM772
Type: Master's thesis
Year: 2008
Downloads: 94
Quote: 2
Read: Download Dissertation


With a growing number of ultra-high pressure long-distance transmission lines in China 's built and running , large-capacity transformer applications are increasing. Power transformers are widely used in the transmission and distribution of electric power system in every aspect , therefore, a higher demand for transformer protection reliability and speed off . Differential protection is the primary protection of the transformer , the transformer when power is restored after excision of the load closing or external fault , the differential circuit magnetizing inrush current will flow differential protection does not recognize and survive the current malfunction occurs . Therefore , the correct identification of magnetizing inrush is to ensure that the key transformer differential protection and reliable operation . Wavelet transform in recent years, the rapid development of a data processing and analysis methods , it has a multi-resolution analysis and time - frequency localization characteristics , especially suitable for the characteristics used to extract the signal edge and peak mutations could measure the signal singularity sex . Transformer inrush current has the singularity, Therefore, the wavelet transform is applied to the recognition of the transformer inrush current . This paper first described the basic principles of the transformer differential protection , and then analyze the magnetizing inrush mechanism and features several magnetizing inrush current identification of principles and methods , and compare its analysis . Subsequently, on the basis of simulation using MATLAB software , select the appropriate db wavelet wavelet transform and analysis of the inrush current and internal fault current . Identification of magnetizing inrush on the basis of the previous intermittent angle principle , the method of the traditional precise measurement excitation inrush intermittent angle to do a little improvement , and direct analysis of the waveform signal wavelet transform , establish criterion , simulation , simulation results show that the method can effectively extract the inrush current distortion characteristics , brake module can be used as a transformer differential protection .

Related Dissertations

  1. Feature Extraction, Selection and Combination in Lipreading,TP391.41
  2. Research on Identification System of Cashmere and Wool Fiber,TS101.921
  3. Characteristics of sensory stimulation evoked,R318.0
  4. Network transmission ROI image coding algorithm,TN919.81
  5. Image Fusion Algorithms Based on Multi-scale Analysis,TP391.41
  6. Feature Extraction Technologies Research and Implementation of 3D Models Based on Wavelet Transform,TP391.41
  7. An Algorithm on Clustering and Anomaly Detection for Multiple Data Streams,TP311.13
  8. Research on Information Hiding Based on Images,TP309.7
  9. Design and Implication of Image Compression System Based on Wavelet and DM6446,TP391.41
  10. The Study of Vibration Signal Analysis System Based on Wavelet Fractal Theory,TN911.6
  11. Chattering Elimination and Terminal Sliding Mode Surface Design for Sliding Mode Control,TP13
  12. Combined DWT Dynamic Data Reconciliation Research and Application,TP274
  13. Traffic Prediction Model Based on Wavelet and Markov,TP393.06
  14. Study on a Hybrid Mechanism Based on Tripod Universal Wrist & Biglide Parallel Mechanism,TH112
  15. The Study of Image Watermark Base on Discrete Wavelet Transformation,TP309.7
  16. Research on Automatic Picking of First Arrival Based on Wavelet Transform,TP311.52
  17. The Compression and Application of the Brain CT Image,TP391.41
  18. Inspection and Recognition on a Class of Tool Processing Trace,TP391.41
  19. The Research and Design of a Fire Detection System Based on Combustion Audio Recognition,X924.4
  20. The Realization and Study of a Scalable Data Encoder Based on SPIHT,TN762
  21. Research and Implementation of Dwt-based Video Codec System at Low Bit Rates,TN919.81

CLC: > Industrial Technology > Electrotechnical > Transmission and distribution engineering, power network and power system > Power system protection > Protection of components
© 2012 www.DissertationTopic.Net  Mobile