| The fast and accurate PD detection of high voltge cables is meaningful to ensure the reliable operation of power systems. Based on current detection methods of PD detection of high voltge cables, a high-voltage cable PD live detection system is developed based on wideband electromagnetic coupling method, which is, making use of Rogowski coil current sensor to detect theground wire current of high voltage cable to realize the fast and accurate PD detection. First, based on PSCAD, the paper establishes a high-voltage transmission cables PD model and researches the propagation characteristics and attenuation of the PD pulse signal in cable. Then through theoretical analysis the change of amplitude-frequency characteristics of Rogowski coil with coil variation of parameters is researched, and through the experiment, the effect of different core materials, permeability, the coil turns and the integral resistance on coil characteristics is researched, at last the micro-current sensor for high-voltage cable PD detection is designed and fabricated and the experimental results show that the sensitivity of the sensor is high and the linearity is better and is able to meet the needs of PD detection. On signal processing, collection and analysis, use of the existing detector amplifier to detect and amplify PD signal, and based LabVIEW, PD detection system is developed which realizes acquisition, display, analysis and preservation functions of PD signal. At last, make use of the developed system live detect the35kV ans lOkV cables of Tanggongta110kV substation and Changsheng220kV substation of Xuejiawan in Neimenggu Province, the detect results proved the effectiveness of the system. |
PDF Full Text Request