Study On Partial Discharge Ultrasonic Detection And Positioning System Of Switch Cabinet

For metal enclosed power equipment such as switchgear,some insulation defects are easy to cause partial discharge.Therefore,the detection and location of partial discharge in normal operation of switch cabinet is a necessary means to avoid hidden insulation hazards of equipment.However,the research on pd detection and location is mainly carried out in the application of technology and data mining,and there are still many difficulties to be solved for the localization algorithm and pd detection system.Therefore,this paper has carried on the thorough research to the partial discharge phenomenon,and has designed the corresponding hardware and software system,through to the ultrasonic signal monitoring,has realized the switch cabinet partial discharge detection and location.Firstly,the detection and location of partial discharge are analyzed in detail,and three basic signal detection methods are introduced.Based on the analysis of the research status at home and abroad,the keynote of this paper is laid,which provides the theoretical basis and background foundation for the subsequent design.Secondly,the partial discharge model of switch cabinet was built,the selection and construction of ultrasonic detection device was completed,and the design of ultrasonic signal acquisition system was completed based on LABVIEW software,and the discharge signal was successfully detected.In addition,the delay estimation algorithm is innovated and improved by combining cubic correlation with generalized cross-correlation,and a new weighted function is designed.The simulation results are compared and the performance of the algorithm is analyzed.The results show that the algorithm improves the accuracy and anti-noise of delay estimation.Finally,the improved particle swarm optimization(PSO)algorithm is combined with the principle of dimensional-reduction projection to complete the location of the local discharge power supply in the experimental model.The effectiveness and superiority of the improved algorithm in this location are proved by comparing the location effect before and after the improvement.