Investigation of an Online Fault Gas Monitoring System for Hermetically Sealed Power Transformers

authored by

Behnam Balali, Mohammad Akbari Azirani, Moritz Kuhnke, Peter Werle, Asghar Akbari Azirani, Wolfgang Sorgatz

Abstract

Hermetically sealed oil-filled power transformers are manufactured with a sealed and gastight tank. A gas cushion, usually compressed nitrogen or dry air, is maintained above the liquid. In case of severe faults, the generation of a considerable amount of fault gases is expected, which will, in the case of hermetically sealed power transformers, gradually escape from the insulating liquid and diffuse into the gas cushion. As a cost-effective and compact alternative to gas chromatography, a prototype semiconductor-based online monitoring system of undissolved fault gases was developed by the Schering-Institute. In this contribution, the new monitoring system is investigated regarding its accuracy under different conditions. The developed online monitoring system in this contribution is based on a set of integrated sensors housed in an aluminium enclosure, a controller board, a DC power supply, and a device software, tracking the concentration of fault gases in the gas cushion continuously, through which faults in the insulating system can be detected early. Furthermore, physical parameters such as temperature, pressure, oxygen, and humidity are also recorded permanently. The proposed online monitoring system showed convincing and promising results.

Organisation(s)

High Voltage Engineering and Asset Management Section (Schering Institute)
Institute of Electric Power Systems

External Organisation(s)

K.N. Toosi University of Technology
Energy Support GmbH

Type

Conference article

Journal

IET Conference Proceedings

Volume

2023

Pages

295-300

No. of pages

6

Publication date

2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

General Engineering

Electronic version(s)

https://doi.org/10.1049/icp.2024.0504 (Access: Closed)