Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay

In practical engineering, due to the residual magnetism in the iron core of the converter transformer, the inrush current is generated in the case of no-load closing, and the inrush current leads to an oil flow surge inside the converter transformer. Under the influence of oil flow, the gas relay pl...

Full description

Saved in:
Bibliographic Details
Main Authors: Wenhao He, Zhanlong Zhang, Yu Yang, Jiatai Gao, Xichen Pei, Jun Deng, Zhicheng Pan, Jinzhuang Lv, Hongliang Yao
Format: Article
Language:English
Published: MDPI AG 2025-02-01
Series:Applied Sciences
Subjects:
Online Access:https://www.mdpi.com/2076-3417/15/4/2235
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849720118320300032
author Wenhao He
Zhanlong Zhang
Yu Yang
Jiatai Gao
Xichen Pei
Jun Deng
Zhicheng Pan
Jinzhuang Lv
Hongliang Yao
author_facet Wenhao He
Zhanlong Zhang
Yu Yang
Jiatai Gao
Xichen Pei
Jun Deng
Zhicheng Pan
Jinzhuang Lv
Hongliang Yao
author_sort Wenhao He
collection DOAJ
description In practical engineering, due to the residual magnetism in the iron core of the converter transformer, the inrush current is generated in the case of no-load closing, and the inrush current leads to an oil flow surge inside the converter transformer. Under the influence of oil flow, the gas relay plate will be deflected, and when the deflection angle is too large, the gas relay will malfunction. Because of the lacking research on the influence of the misoperation of the gas relay under the excitation inrush of the converter transformer, it is difficult to effectively suppress the misoperation of gas relay under inrush current. Therefore, the finite element model of the electromagnetic hydraulic coupling of the converter transformer is established in this paper to obtain the oil flow velocity through the gas relay under the inrush current. A fluid–solid coupling model was established inside the gas relay to study the deflection characteristics of the baffle of the gas relay under the inrush current, and the relationship between the inrush current amplitude and the deflection angle of the baffle was mathematically fitted to effectively predict whether the gas relay has the risk of misoperation. From the experimental results, it can be seen that when the amplitude of the inrush current exceeds 6.37 kA, the gas relay will have the risk of misoperation. Finally, the influence of oil flow impact on the gas relay baffle under multiple cycles is considered. The results can provide an effective reference for analyzing the diagnosis of gas relay misoperation under the effect of inrush current.
format Article
id doaj-art-ed897157347d4593a63fb6c98bd11ca4
institution DOAJ
issn 2076-3417
language English
publishDate 2025-02-01
publisher MDPI AG
record_format Article
series Applied Sciences
spelling doaj-art-ed897157347d4593a63fb6c98bd11ca42025-08-20T03:12:01ZengMDPI AGApplied Sciences2076-34172025-02-01154223510.3390/app15042235Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas RelayWenhao He0Zhanlong Zhang1Yu Yang2Jiatai Gao3Xichen Pei4Jun Deng5Zhicheng Pan6Jinzhuang Lv7Hongliang Yao8School of Electrical Engineering, Chongqing University, Chongqing 400044, ChinaSchool of Electrical Engineering, Chongqing University, Chongqing 400044, ChinaSchool of Electrical Engineering, Chongqing University, Chongqing 400044, ChinaSchool of Electrical Engineering, Chongqing University, Chongqing 400044, ChinaSchool of Electrical Engineering, Chongqing University, Chongqing 400044, ChinaMaintenance and Test Centre, EHV, China Southern Power Grid, Guangzhou 510663, ChinaMaintenance and Test Centre, EHV, China Southern Power Grid, Guangzhou 510663, ChinaMaintenance and Test Centre, EHV, China Southern Power Grid, Guangzhou 510663, ChinaLuoyang Yanshi Power Supply Company, State Grid Henan Electric Power Company, Luoyang 471900, ChinaIn practical engineering, due to the residual magnetism in the iron core of the converter transformer, the inrush current is generated in the case of no-load closing, and the inrush current leads to an oil flow surge inside the converter transformer. Under the influence of oil flow, the gas relay plate will be deflected, and when the deflection angle is too large, the gas relay will malfunction. Because of the lacking research on the influence of the misoperation of the gas relay under the excitation inrush of the converter transformer, it is difficult to effectively suppress the misoperation of gas relay under inrush current. Therefore, the finite element model of the electromagnetic hydraulic coupling of the converter transformer is established in this paper to obtain the oil flow velocity through the gas relay under the inrush current. A fluid–solid coupling model was established inside the gas relay to study the deflection characteristics of the baffle of the gas relay under the inrush current, and the relationship between the inrush current amplitude and the deflection angle of the baffle was mathematically fitted to effectively predict whether the gas relay has the risk of misoperation. From the experimental results, it can be seen that when the amplitude of the inrush current exceeds 6.37 kA, the gas relay will have the risk of misoperation. Finally, the influence of oil flow impact on the gas relay baffle under multiple cycles is considered. The results can provide an effective reference for analyzing the diagnosis of gas relay misoperation under the effect of inrush current.https://www.mdpi.com/2076-3417/15/4/2235inrush currentgas relayoil flow characteristicsfluid–solid coupling
spellingShingle Wenhao He
Zhanlong Zhang
Yu Yang
Jiatai Gao
Xichen Pei
Jun Deng
Zhicheng Pan
Jinzhuang Lv
Hongliang Yao
Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay
Applied Sciences
inrush current
gas relay
oil flow characteristics
fluid–solid coupling
title Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay
title_full Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay
title_fullStr Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay
title_full_unstemmed Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay
title_short Risk Assessment Study of Oil Flow Under Inrush Current on the Misoperation of Converter Transformer Gas Relay
title_sort risk assessment study of oil flow under inrush current on the misoperation of converter transformer gas relay
topic inrush current
gas relay
oil flow characteristics
fluid–solid coupling
url https://www.mdpi.com/2076-3417/15/4/2235
work_keys_str_mv AT wenhaohe riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT zhanlongzhang riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT yuyang riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT jiataigao riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT xichenpei riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT jundeng riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT zhichengpan riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT jinzhuanglv riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay
AT hongliangyao riskassessmentstudyofoilflowunderinrushcurrentonthemisoperationofconvertertransformergasrelay