On the Feasibility of Gap Detection of Power Transformer Partial Discharge UHF Signals: Gap Propagation Characteristics of Electromagnetic Waves

This study analyzed the transformer electromagnetic gap propagation characteristics. The influence of gap size is also analyzed, and the results experimentally verified. The obtained results indicated that the gap propagation characteristics of electromagnetic wave signals radiated by the partial discharge (PD) source in different directions are substantially different. The intensity of the electromagnetic wave in the gap reaches a maximum at a gap height of 1 cm; and inside the gap, the intensity of the electromagnetic wave depicted an increasing trend at the tail area of the gap. Finally, from the obtained results, some suggestions on where to install sensors in practical systems for ultra high frequency (UHF) PD signal detection in the transformer gap are provided. The obtained results confirmed the feasibility of using this approach. These results can be seen as a benchmark and a challenge for further research in this field.

[1]  M.D. Judd,et al.  Partial discharge monitoring of power transformers using UHF sensors. Part I: sensors and signal interpretation , 2005, IEEE Electrical Insulation Magazine.

[2]  Song Xiao,et al.  Antipodal Vivaldi Antenna to Detect UHF Signals That Leaked Out of the Joint of a Transformer , 2017 .

[3]  Suwarno,et al.  Sensitivity verification and determination of the best location of external UHF sensors for PD measurement in GIS , 2012, 2012 IEEE International Conference on Condition Monitoring and Diagnosis.

[4]  M.D. Judd,et al.  Simulating propagation of UHF signals for PD monitoring in transformers using the finite difference time domain technique [power transformers] , 2004, The 17th Annual Meeting of the IEEE Lasers and Electro-Optics Society, 2004. LEOS 2004..

[5]  Li Yanming.  Propagation Characteristic of Partial Discharge Ultra High Frequency Signals Outside Transformer , 2008 .

[6]  Li Yan-ming.  Emulational Study on the Propagation of UHF Signal Emitted by PD in Transformers , 2007 .

[7]  Okan K. Ersoy,et al.  Diffraction, Fourier Optics and Imaging , 2006 .

[8]  S. Jayalalitha,et al.  Location of partial discharges in transformers , 2003, 2003 Annual Report Conference on Electrical Insulation and Dielectric Phenomena.

[9]  Y. M. Kim,et al.  Sensitivity verification and application of UHF sensor for partial discharge measurement in high voltage power transformer , 2012, 2012 IEEE International Conference on Condition Monitoring and Diagnosis.

[10]  M. D. Judd,et al.  Design and Optimization of UHF Partial Discharge Sensors Using FDTD Modeling , 2017, IEEE Sensors Journal.

[11]  Chen Jinxian.  Detection and Location of Partial Discharge in Power Transformers Based on Dielectric Window and UHF Sensors , 2014 .

[12]  Stefan Tenbohlen,et al.  Application of UHF sensors for PD measurement at power transformers , 2017, IEEE Transactions on Dielectrics and Electrical Insulation.

[13]  Ouyang Xu-don.  Theoretical Analysis of Impact to Detection Sensitivity for Installation Mode of UHF Sensors in Transformer PD Test , 2014 .

[14]  Li Yan-ming.  UHF Signal External Detection of Partial Discharge in Transformers , 2007 .

[15]  B. F. Hampton,et al.  Dielectric windows for UHF partial discharge detection , 2001 .

[16]  G. Stone,et al.  Fundamental Limitations in the Measurement of Corona and Partial Discharge , 1982, IEEE Transactions on Electrical Insulation.