In this work, the extended Debye model or Fourier transform is adopted to convert the polarization and depolarization current test results from the time domain into the frequency domain at low frequencies, thereby shortening the test time but producing large errors when the oil-paper insulation exhibits nonlinear characteristics. The voltage-current response characteristics of samples with three different moisture contents are tested to study the influence of moisture on the nonlinear characteristics. Hammerstein-Wiener (H-W) equivalent mathematical model is proposed for time-frequency domain conversion, and the results from this model and two formal methods are compared. The findings show that the errors of the two conventional methods increase with nonlinearity. The H-W model accurately depicts the nonlinear dielectric response of oil-paper insulation and thus can provide high-precision time-frequency domain conversion data.

中文翻译：

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潮湿油纸绝缘的非线性介电响应特性及HW模型在时频转换中的应用

本工作采用扩展的德拜模型或傅里叶变换，将极化去极化电流测试结果从时域转换到低频时的频域，​​从而缩短了测试时间，但在油纸绝缘表现出较大的误差时会产生较大的误差。非线性特性。测试了三种不同含水量样品的电压-电流响应特性，研究水分对非线性特性的影响。提出了用于时频域转换的 Hammerstein-Wiener (HW) 等效数学模型，并比较了该模型和两种形式化方法的结果。研究结果表明，两种常规方法的误差随着非线性而增加。