Lc Features Combined Chirplet Transform and Fractal Theory on High Voltage Insulators
نویسندگان
چکیده
The voltage grade of electrical transmission line is getting higher and higher, consequently, flashover of transmission insulators is getting more and more severe in high-voltage (HV) and ultra-high-voltage (UHV) systems under serious pollutions, which menaces the safety of power transmission system heavily. The crux to enhance the security of power system is to discover ways of monitoring states of insulator’s surface by some eigenvalues. A new method, combined chirplet transform with fractal theory, was proposed in this paper, and is taken as the ruler to define fractal dimension, which is used to describe characteristics of signals. Chirplet-fractal dimension is defined as the sum of residues of decomposed signals. The fractal characteristics of leakage current during flashover are obtained from this dimension. The results show that the chirplet-fractal dimension efficiently describes the information of arcs discharge in LC, and it is also a good eigenvalue for flashover discrimination and risk prediction.
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