738 / 2022-03-31 20:24:16

Relationship between X - ray Pulse and Partial Discharge Signal in XLPE Cable

X-ray pulse，pulse current method，XLPE cable，bubble defect

IEEE ICHVE 2022 / 1-PAGE ABSTRACT

Relationship between X - ray Pulse and Partial Discharge Signal in XLPE Cable

Ju KONG, Shusheng ZHENG, Zongheng ZHANG, Yan ZHAO, Xiaohu YAN

State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources (North China Electric Power University)

Kongju0308@163.com



Purpose/Aim

X-ray can reduce the partial discharge starting voltage and statistical delay of bubble defects, but the relationship between X-ray and partial discharge signal is rarely studied. In this paper, the mechanism relationship between X-ray pulse and partial discharge signal is revealed by synchronous measurement of X-ray pulse and partial discharge pulse current signal, which provides theoretical guidance for partial discharge detection of bubble defects under X-ray.

Experimental/Modeling methods

Typical bubble defects were made on XLPE cables. Partial discharge under X-ray excitation was detected by pulse current method and high-frequency current method. At the same time, the X-ray pulse emitted by continuous X-ray machine is measured, so as to achieve the purpose of synchronous detection of X-ray pulse signal and partial discharge pulse current signal. The step-by-step boost method was used in the test. When the target voltage was raised, X-ray was applied to the defect. If partial discharge occurred, the data of X-ray pulse and partial discharge pulse were recorded. If no partial discharge occurred, the boost was continued until partial discharge occurred and the data were recorded.

Results/discussion

The experimental results show that X-ray can significantly reduce the initial partial discharge voltage ; moreover, the voltage reaches the initial voltage of partial discharge under X-ray(XPDIV). One X-ray pulse can excite multiple partial discharge signals, which significantly increases the discharge repetition rate and improves the sensitivity of XLPE cable air gap defect detection.

Conclusions

The following conclusions can be drawn from the experiment : ( 1 ) It is verified that X-ray has strong excitation effect on partial discharge of bubble defects, and one X-ray pulse can stimulate multiple discharges. ( 2 ) X-ray can improve the detection sensitivity of XLPE bubble defect, which provides a new method for XLPE cable bubble defect detection.

Keywords—X-ray pulse，pulse current method，XLPE cable，bubble defect