A new Method for Detecting Over Flux in Power Transformers

Ghodrati, Cyrus; Niasati, Mohsen; Moravej, Zahra

doi:10.22075/mseee.2025.37572.1207

A new Method for Detecting Over Flux in Power Transformers

Document Type : Research Article

Authors

Cyrus Ghodrati

Mohsen Niasati

Zahra Moravej

Faculty of Electrical and Computer Engineering , Semnan University, Semnan, Iran.

10.22075/mseee.2025.37572.1207

Abstract

This paper presents a new method for monitoring and identifying over-flux in power transformers based on harmonic analysis. Today, over-flux protection of power transformers is done by monitoring the voltage-to-frequency ratio. When the ratio value exceeds the unit value, it should be detected. This method may cause incorrect operation of the power transformer's over-flux protection due to voltage and frequency variations in the network. This paper proposes a new method for detecting and identifying power transformer over-flux based on the total harmonic distribution. In addition, the equation and curve of flux and total harmonic distortion (THD) changes in the power transformer were obtained using DIGSILENT software, which can be used to design the over-flux protection. Based on the simulation results, a simple equation was presented to estimate the transformer flux value based on the THD value.

Keywords

Overflux

Harmonic

Flux

Power Transformer, Detecting

Total Harmonic Distortion

Subjects

Power System

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