Applications of chaos theory on Partial Discharge detection and character analysis

Partial Discharge (PD) signals character analyzing and interference suppressing are very important for PD on-line measurement. In this paper, chaos theory is introduced in the PD on-line monitoring. The mechanism of PD phenomena has been researched by series of typical insulation defect PD experiments in the lab. Through calculating the non-linear dynamics character of PD detecting signal time sequence, such as Lyapunov exponent, correlation dimension, Kolmogorov entropy, the PD signal is proved to be a non-linear Chaotic dynamics system. The farther investigation shows that the chaotic dynamics character of PD detecting signal such as Maximum Lyapunov exponent etc. can be used to the PD pattern identification. The experiment diagram and experiment result are presented in this paper, which shows this method has a favorable to PD pattern identification. In addition, a special chaotic system is put forward to suppress the periodic narrow bandwidth interference and periodic pulse interference. This chaotic system is made up of Duffing-Homes equation. Based on the advanced knowledge of periodic interference characters such as the frequency and phase, setting the appropriate periodic parameter disturbance to control the chaotic system, the narrow bandwidth interference and pulse interference are accurately detected and suppressed with the special chaotic system. Experiments show that the chaotic system can effectively suppress the periodic interference without any influence to PD pulse. It’s significant to PD signal detecting and insulation defect diagnosing.