The PD Detection Methods Of High Voltage Cable Joint

The high voltge cable is one of the important parts in power system. Giving on-line PD detection to the high voltge cable is the important and meaningful way to ensure the high voltge cable reliable operation. On the research of the PD detection of the high voltge cable joint, the paper reserches the line model of the power cable and identifies the parameters which can characterize the pulse. By establishing the model of the power cable, the paper gives a simulation study on the PD signal propagation characteristics in the high voltge cable and researches the propagation of the pulse signal in cable. Then the paper designs and makes the wideband current sensor which is aiming at the PD characteristic of the high voltge cable joint and determines the optimal parameters of the wideband current sensor, which makes the wideband current sensor have wide workband and better amplitude-frequency characteristics. Therefore, the paper gives a test to the amplitude-frequency characteristics of the wideband current sensor.The paper studies the ultersound measurement technology on PD detection. Through the research on the principle of the ultersound detection to the PD, the paper chooses the appropriate ultersound detection system, which is suit for the PD of the high voltge cable. At last, to the reasons of the power cable Insulation fault, the paper simulates the fault of the cable joint and designs 4 typical discharge models. Under laboratory conditions, the paper builds the PD experiment platform and uses the wideband current sensor associated with the ultersound sensor to give the PD detection on the 4 typical discharge models, which realizes the online PD detection and pattern recognition of the high voltge cable joint.