Fault on-line diagnosis and early warning method of flameproof dry-type transformer for mine

Abstract

The invention provides a fault on-line diagnosis and early warning method of a flameproof dry-type transformer for mine in order to raise the accuracy and rapidity of fault diagnosis. The method comprises the following steps: determining monitoring quantity; extracting characteristic values: extracting a three-dimensional spectra parameter and two-dimensional statistical parameter in a partial discharge signal as characteristic quantities, with regard to operation voltage, current and iron core leakage current, extracting effective values of the operation voltage, the current and the iron core leakage current as characteristic values, and taking real-time values of a temperature parameter as characteristic quantities; using a normalization method to calculate a corresponding value of each characteristic quantity and taking the corresponding value as an input parameter of an intelligent diagnosis system; collecting values of each monitoring quantity under different environment, and obtaining training and testing samples of a nerve network under corresponding environment; establishing a nerve network: selecting a generalized RBF nerve network intelligent diagnosis method to establish a nerve network; utilizing a sample data training nerve network and forming a fault diagnosis tool; establishing a database; storing collected real time data and the above diagnosis result into a ground server real-time database and a real-time early warning information table, and carrying out diagnosis and early warning through an expert system.

Description

technical field [0001] The invention relates to the field of fault diagnosis of large-scale power equipment used in mines, in particular to an on-line fault diagnosis and early warning method for flameproof dry-type transformers used in mines. technical background [0002] There are many reasons for the failure of mine explosion-proof dry-type transformers, among which partial discharge is one of the main reasons for insulation aging and breakdown. The partial discharge of the winding is mostly caused by the overvoltage of the winding. Long-term discharge will cause the temperature of the winding to rise, which will lead to insulation breakdown and short-circuit fault of the winding. Overcurrent will also cause the temperature of the transformer to rise, resulting in carbonization of the insulation, an increase in the amplitude of partial discharge, and a shift in the discharge phase; poor cooling of the winding, overload, and long-term operation will cause insulation aging;...

AI Technical Summary

Problems solved by technology

These environmental factors influence and interact with each other, thus accelerating the deterioration process of transformer insulation

Due to the high temperature of the underground environment, when partial discharge occurs in the underground transformer, the discharge amplitude is larger than that at normal temperature, and the initial phase of the discharge will also shift, thus accelerating the impact on the insulation of the transformer

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