Performance Evaluation Method And Platform Of The Partial Discharge Detection Sensor For High Voltage Cable

Partial discharge(PD)detection of cables is an effective way to judge the insulation condition of cables.In particular,the on-line monitoring technology of PD can reflect the health status of running power cables in real time.The performance of the PD detection device is the key component for effectively identifing partial discharge faults.To carry out performance verification can accurately recognize unqualified products and avoid the inaccurate PD fault detection.In this paper,the existing problems of test platform for checking the frequency response characteristic of high-frequency current transformer(HFCT)has been analyzed.And the of structure coaxial transmission cavity is proposed to improve the test platform and the reasonable arrangement of test platform has been determined through Pspice simulation.The actual calibration of HFCT proves the effectiveness of the improved test platform.Then,a nanosecond pulse source circuit of positive polarity was developed by using RF transistor.The equivalence between the impulse response method and the sine wave frequency sweep method in the verification of the frequency response characteristic of HFCT was verified by the sensor measurement.And the miniaturized prototype for verifying the frequency response characteristic of HFCT has been developed.Finally,theoretical transmission characteristics of the capacitive coupling sensor were determined by theoretical analysis and experiment calibration.The performance verification platform was built for capacitance-coupling sensor.The model evaluation of different capacitive coupling sensors has been carried out to determine the transmission characteristics and discharge detection sensitivity.