Detection Of GIS Partial Discharge Based On Ultrasonic

With the rapid development of China's power industry,Gas Insulted Switchgear(GIS)has been widely used because of its small footprint,high reliability and short installation period.However,once a fault occurs to the equipment,it will bring huge economic losses.Through the partial discharge detection on GIS equipment,the insulation defects can be found in time and effectively.Among the partial discharge detection methods,the ultrasonic detection method is favored by domestic and foreign scholars because of its easy installation,strong anti-interference ability and no influence on the normal operation of equipment.In consideration of that,this thesis designs a GIS partial discharge detection device based on the ultrasonic detection method.Firstly,this thesis describes the causes of partial discharge in GIS,the ultrasonic generation mechanism of partial discharge and common methods of signal processing based on the theory of partial discharge.It provides a theoretical basis for the design of the discharge model and the research of the ultrasonic testing method.Secondly,according to the frequency characteristics of ultrasonic generated from the partial discharge,the hardware design of partial discharge detection device is completed.The hardware part takes DSP as the core chip.The selection of the sensor,the design of the ultrasonic signal conditioning circuit and other functional circuits are emphasized.Thirdly,the software design of the detection device is completed based on the host computer LabVIEW and lower computer DSP chip,realizing the functions of data acquisition,signal processing and analysis,results display and data management,etc.The emphases are on the extraction of PD signals based on digital filtering and wavelet denoising,and algorithm realization of PD feature parameter extraction.Finally,under the condition of the laboratory,complete partial discharge simulation test and the experimental results were analyzed.Then under the condition of laboratory,partial discharge simulation test has been carried out,and the whole debugging and functional test of the detection device have been completed.Finally,the test result has been analyzed.The partial discharge detection device designed in this thesis can effectively identify the partial discharge signal in the experimental environment,extract the partial discharge characteristic parameters,obtain the correlation diagram of discharge and realize the intellectualization and visualization of detection device.It provides the theoretical and experimental basis for the detection of partial discharge in different types.