套管油纸绝缘受潮与老化的介电响应非线性特性和辨识方法

Dielectric response has the advantages of rich insulation information and no damage to insulation. As a new nondestructive diagnosis method of oil paper insulation, it has attracted extensive attention at home and abroad. Oil paper insulation shows similar dielectric response characteristics when affected by moisture and aging, which makes it difficult to popularize and apply this method. This paper is to study the nonlinear characteristics of dielectric response and insulation state identification method of oil paper insulated transformer bushing under variable voltage excitation. The mechanism and model of the nonlinear dielectric response of damp oil paper samples were investigated, followed by a study of the nonlinear dielectric response traits and characteristic quantities of thermally aging oil paper insulation. The relationship was established between oil paper insulation nonlinear loss peak, aging degree and water content, and the state e-valuation and differentiation of moisture and aging of bushing oil paper insulation was realized.