Partial discharge diagnosis and remaining useful lifetime in XLPE extruded power cables under DC voltage: a review

Influence of Thermal Aging on Space Charge Characteristics and Electrical Conduction Behavior of Cross-Linked Polyethylene Cable Insulation

“…XLPE is extensively used as the insulation material for HVDC cables due to its exceptional electrical, thermal, and mechanical properties [ 2 , 3 ]. However, during cable operation, factors such as electricity, heat, mechanical stress, and moisture can induce thermal aging [ 4 ], partial discharge [ 5 ], electrical tree aging [ 6 ], and water tree aging [ 7 ]. Recent research has demonstrated that the pyrolysis reaction of molecular chains during thermal aging leads to an increase in the carbonyl index of materials [ 8 ], a decrease in crystallinity [ 9 ], and a reduction in activation energy [ 10 ].…”

Recursive Parameter Estimation and Its Convergence for Multivariate Normal Hidden Markov Inhomogeneous Models

“…The effect of this observation is usually called state [2]. HMM is widely applied in various problem areas in the form of time series data such as air pollution problems [3], [4], weather predictions [5], [6], stock price predictions [7], [8], [9], [10], [11], speech recognition [12], [13], [14], prediction of DNA sequences [15] [16], and and It is hoped that it can be applied to diagnose partial discharge acoustic in insulation [17], [18], [19], [20]. This is because HMM maintains relevance to the issues discussed and offers simplification in calculations (memoryless properties) [21].…”