The Research On The Partial Discharge Fault Location Of Transformer Based On Improved UCA-RB-MUSIC Algorithm

In the power system,the insulation level of power transformers is related to their performance,and is also crucial for the reliability and safety of system power supply.However,partial discharge is the direct reason for the reduction of its insulation strength,and the condition of partial discharge has also become a very important indicator of its insulation performance detection.In order to ensure the safe operation of transformers and reduce the loss of power transformers in case of insulation failure as much as possible,scholars from all over the world have invested a lot of time in the detection and location of partial discharge in transformers.However,most partial discharge detection methods have their limitations in practical applications,and the commonly used acoustic detection methods also have problems such as insufficient positioning accuracy and susceptibility to interference from coherent signals.Therefore,proposing an improved acoustic source localization algorithm for transformer partial discharge fault location is of great significance.This dissertation focuses on the research of transformer partial discharge fault location based on the proposed improved UCA-RB-MUSIC(Uniform Circular Array Real Beamspace Multiple Signal Classification)algorithm.Firstly,the principles and traditional algorithms of acoustic source localization is studied,and an improved UCA-RB-MUSIC algorithm is proposed.Secondly,a mathematical model and simulation model for narrowband partial discharge acoustic signals is established;Next,in order to test the positioning performance of the improved UCA-RB-MUSIC algorithm and verify its applicability to the direction finding of narrowband partial discharge acoustic signals,simulation research on narrowband partial discharge signal direction finding based on it and traditional algorithms is carried out,and the simulation results of them are compared and analyzed.Afterwards,the mechanism and characteristics of the generation of transformer partial discharge acoustic signals is studied,and the necessity of frequency domain focusing of partial discharge acoustic signals is analyzed.A mathematical model and simulation model for broadband partial discharge acoustic signals is established.Then,using the simulation model and the improved UCA-RB-MUSIC algorithm combined with the broadband focusing algorithm,simulation research is conducted on the direction finding and positioning of single and dual partial discharge sources,and the direction finding and positioning errors are analyzed to verify the feasibility and accuracy of the proposed improved algorithm for direction finding and positioning of broadband partial discharge signal sources.Finally,a transformer partial discharge test system is built to further verify the feasibility and accuracy of the improved UCA-RB-MUSIC algorithm applied to the direction finding of single and double partial discharge sources in the actual environment by using the method of testing analysis.The experiment use traditional algorithms and improved UCA-RB-MUSIC algorithms for direction finding of single and dual partial discharge sources,respectively.Then compare and analyze the experimental results of them,and determine the direction finding accuracy of the improved algorithm.