# Increasing Certainty of Fault Identification in Power Transformers of Power Plants by Setting Parameters for Fuzzy Model

## Authors

• Eugen I. Bardyk Igor Sikorsky Kyiv Polytechnic Institute, Ukraine
• Nickolai V. Kosterev Igor Sikorsky Kyiv Polytechnic Institute, Ukraine
• Nickolai P. Bolotnyi Igor Sikorsky Kyiv Polytechnic Institute, Ukraine

## Keywords:

Model, Fuzzy logic, Electrical equipment, Risk assessment, Damage, Failure

## Abstract

Background. Problem of ensuring reliability and safety operation of thermal, nuclear and hydro power plants is exacerbated under increasing accident in modern electric power systems due to power equipment failures. Therefore, deve­lopment of adequate mathematical models for technical condition determination and risk assessment of power transformer failure in power plants is relevant.

Objective. The aim of the paper is to improve the diagnostic fuzzy model of power transformer technical condition by setting parameters and risk failure assessment under presence damage.

Methods. The mathematical model of power transformer used approaches based on fuzzy sets theory, fuzzy logic and nonlinear optimization methods. Risk assessment of power transformer failure under presence damage was solved based on formed hierarchy factors and parameters of influence on integral risk indicator of power transformer failure.

Results. The necessity of complex simulation of technical condition of power transformer and electric power system modes is substantiated. The fuzzy model of power transformer technical condition evaluation was upgraded by parametrically identifying the optimal function values of fuzzy terms of linguistic variables.

Conclusions. A mathematical model of risk assessment of power transformer failure with presence damage was proposed for emergency risk estimation in electric power systems under electrical equipment failures.

## Author Biographies

### Eugen I. Bardyk, Igor Sikorsky Kyiv Polytechnic Institute

Євген Іванович Бардик

### Nickolai V. Kosterev, Igor Sikorsky Kyiv Polytechnic Institute

Микола Володимирович Костерєв

### Nickolai P. Bolotnyi, Igor Sikorsky Kyiv Polytechnic Institute

Микола Петрович Болотний

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