Research And Design Of On-line XLPE Cable Monitoring System

As electricity more and more important for human, electric power safety should be taken seriously. Power cable is one of the important equipment for power transmission. Its reliability is directly related to the stability of the whole power system. XLPE cable is the most widely used power cable in our everyday life. In order to ensure its stable and reliable operation, it must be test. Traditional off-line test is relatively backward while On-line XLPE cable monitoring is a general tendency. Foreign countries have made certain achievements in the field of on-line XLPE cable monitoring system, but studies in China is under-developed.In this paper, reasons why XLPE cable fault is analyzed. Water tree phenomenon is supposed to be primary determinant cause of XLPE cable fault. This paper summarizes the current research status of on-line XLPE cable monitoring system. Combination with a variety of monitoring methods is thought to be the promising area in on-line XLPE cable monitoring system. The design, encapsulation and experiment of on-line XLPE cable monitoring system has been completed with the method of DC component method and AC superposition method. In aspect of system design, firstly, the theories of DC component method and AC superposition method are elaborated in this paper. We also propose the standards based on the two measurement strategies. Secondly, this paper introduces the design method of each part of the system and key technology, including AC superposed power, signal processing part, signal acquisition part and the upper computer part. Thirdly, we completed the encapsulation of the system, including appearance, panel, interface, accessory, and interior structure. Finally, we design the reasonable experiments. Experiments show that this system can reflect the aging degree of a running XLPE cable to realize the on-line monitoring of the XLPE cable.The theory and method of on-line XLPE cable monitoring is studied in this paper. Good results have been obtained in on-line MV and LV XLPE cable monitoring by an innovative comprehensive use of DC component method and AC superposition method. We have overcome some technical problems of on-line XLPE cable monitoring. We have finished the design, encapsulation and test in on-line XLPE cable monitoring system. We also accumulated some of the test data. The study in this paper has significant meaning in developing and producing on-line XLPE cable monitoring system in order to guarantee the safety and reliability of power supply.