Novel transformer state estimation method based on field-circuit coupling analysis

Abstract

The invention relates to a novel transformer state estimation method based on field-circuit coupling analysis. The method comprises steps as follows: a transformer model is established, and a transformer electromagnetic field is analyzed with a finite element method; a working state of a system where a transformer is located is analyzed and is equivalent to a lumped parameter circuit model in a corresponding state, and circuit analysis is performed; a field-circuit coupling mathematical model of the transformer is obtained on the basis of electromagnetic field analysis and circuit analysis; finite element software is adopted for calculation, a vector magnetic potential A of each node in solution space of the transformer is obtained, other physical quantities such as winding current, impedance and the like of the transformer are solved, and electromagnetic field distribution of the transformer, electromagnetic force borne by a winding and loss of all parts of the transformer are obtained; loss values of all parts of the transformer are taken as heat sources to be loaded to a transformer temperature field model, and transformer temperature field distribution is obtained with a finite volume method. Therefore, estimating analysis of multi-aspect states such as the electromagnetic field distribution of the transformer, the electromagnetic force borne by the winding, temperature field distribution and the like when an electric power system is in different states is realized, basis is provided for overhauling and maintaining work of the transformer, and the working efficiency is improved.

Description

technical field [0001] The invention relates to the field of operation and maintenance of power transformers, in particular to state estimation and failure prediction of transformers under different operating states of a power system. Background technique [0002] With the continuous expansion of the scale of my country's power grid, the voltage level is gradually increased, and the single-unit capacity of the power transformer is gradually increasing. As one of the most important and expensive electrical equipment in the power system, the safety and reliability of the transformer operation is directly related to the power system. security and stability. Therefore, improving the reliability of power transformer operation is of great significance to the safe and reliable operation of the entire power grid. For this reason, it is necessary not only to improve the reliability of the transformer in the design and manufacture process, but also to improve its maintenance and repai...

AI Technical Summary

Problems solved by technology

Such maintenance methods often lead to minor repairs or major repairs of transformers that do not need to be repaired, resulting in waste of manpower, material resources, and financial resources; Safe and Stable Operation of Power System

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