Application on the Water Tree Characteristic Current Detection in XLPE Power Cable with Duffing Chaotic Oscillation

On-line Detection is very important for XLPE Power Cables safety running. The AC Superposition Method is efficient method for XLPE Power Cables\´ water tree deterioration detection. Its key problem is the precision measuring of the weak 1Hz characteristic current that is the token of water tree deterioration. In this paper, theory of controlling chaos is introduced to the XLPE Power Cables water tree characteristic current detection and a special chaotic system is put forward to precise measure the 1Hz characteristic current, which based on that the Duffing chaos oscillation is respond sensitively to the "same frequency" periodic signal and immunity to the "biggish frequency difference" periodic signal with the periodic instigated force. The results of experiment show that the chaotic system can effectively to detect the 1Hz characteristic current precisely and sensitively.