Recurrence Analysis of Time Series of Partial Discharge in Optical-UHF
Combined Sensing
Abstract
Partial discharge (PD) is a dynamical system with nonlinear chaotic
characteristics. Research on the time series of PD is helpful to extract
the discharge mechanism. This paper takes a PD optical-UHF detection
platform to detect the PD signals of typical defects. The optical and
UHF signal are fused to avoid the insensitivity of single method in
specific defects. The phases of PDs are taken as one-dimensional time
series. The PD phase series are reconstructed in phase space and the
attractors and the recurrence plots are presented. The attractors in
phase space characteristic the PD system from predictability, stability,
and complexity. The typical recurrence characteristics such as
recurrence rate, determinism, laminarity, and entropy are extracted as
evaluation parameters. Results show that the PD phase attractors are
more random under low voltage and tends to be more ordered, stable, and
complex when the applied voltage increases. The order of predictability,
stability, and complexity of the four defect types from high to low is:
point discharge, surface discharge, suspended discharge, air-gap
discharge. The recognition accuracy based on recurrence characteristics
achieves 100% with the most basic BPNNs.