基于去极化电流Prony拟合的油纸绝缘德拜参数辨识方法

基于去极化电流Prony拟合的油纸绝缘德拜参数辨识方法Title: Identification Method of Oil-paper Insulation Dissipation Paramete

Prony 基于去极化电流拟合的油纸绝缘德拜参数辨识方法 Title: Identification Method of Oil-paper Insulation Dissipation Parameters Based on Prony Fitting of Depolarization Current Abstract: Oil-paper insulation is commonly used in power transformers to provide electrical insulation and mechanical support. The condition of this insulation is crucial to the overall safety and reliability of the transformer. To accurately evaluate the health of oil-paper insulation, it is essential to identify the dissipation parameters characterizing its condition. This paper presents anovel method for identifying the dissipation parameters of oil-paper insulation based on Prony fitting of depolarization current. 1. Introduction: Oil-paper insulation degradation is acommon problem in power transformers, which can lead to partial discharges, overheating, and eventually failure. The dissipation parameters, such as the relaxation time constant and the equivalent resistivity, are crucial indicators of insulation degradation. However, accurately determining these parameters has been achallenging task. This paper proposes anovel method that utilizes the Prony fitting technique to identify these parameters based on the analysis of the depolarization current. 2. Depolarization Current and Prony Analysis: Depolarization current is the current generated by the release of trapped charges in oil-paper insulation when subjected to an applied voltage. It is adirect indicator of the insulation condition and contains valuable information about the dissipation parameters. Prony analysis is atechnique used to decompose atime-domain signal into asum of exponential functions that can represent relaxation processes. By applying Prony analysis to depolarization current, the relaxation time constant and equivalent resistivity can be obtained. 3. Methodology: The proposed method involves the following steps: a. Measurement of depolarization current: The depolarization current is measured using aspecially designed setup, including astep voltage source and adata acquisition system. b. Preprocessing of the depolarization current: The measured depolarization current is preprocessed to remove noise and unwanted high-frequency components, ensuring accurate analysis. c. Decomposition using Prony analysis: The preprocessed depolarization current is decomposed into asum of exponential functions using Prony analysis. The number of exponential terms is determined through amodel selection process. d. Parameter estimation: The relaxation time constant and equivalent resistivity are