Design Of High Voltage Cable Energized Monitoring System Based On High Frequency Partial Discharge Detection

Power cable is an important part of China’s power industry,which has a decisive impact on the transmission and supply of electric energy.However,insulation deterioration will occur under the action of electricity and heat in the long-term operation of the cable,and partial discharge is the characterization and main cause of insulation deterioration,so it is necessary to determine whether there are abnormal problems by partial discharge detection method.it is helpful to find the hidden danger of power cable in time and avoid more serious consequences caused by power system.At present,many methods have been formed in the detection of partial discharge in power cables.the conventional detection techniques and test methods are only suitable for obvious and typical defects in power cables,and it is difficult to find early insulation defects and potential dangers.therefore,it is of practical significance to study the live monitoring system of power cable.In this study,cross-linked polyethylene(XLPE)is analyzed as an example,and the partial discharge on-line monitoring system is designed.The whole system is divided into hardware and software,and further describes the specific design process of each part.First of all,the paper makes an in-depth theoretical analysis of XLPE cable,and makes clear the basic structural parameters and insulation deterioration mechanism of cable operation.Because the power outage detection means can not meet the requirements of real-time monitoring of cable insulation,the paper carries out the design of high-frequency current sensor and signal acquisition part based on on-line monitoring.According to the collected partial discharge signal,the paper collects the PRPD atlas and TF atlas and separates the signals,and uses the image recognition based on DBSCAN density clustering algorithm to accurately analyze the cable fault.Finally,the prototype is tested and analyzed to verify whether the system can achieve a good detection effect.Two methods of laboratory test and field test are used in the test.According to the final test results,the high-frequency current sensor in this study meets the design standard and can effectively monitor the partial discharge signal,so it can be applied to the actual partial discharge detection of power cables.it shows a broad application prospect.