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CSEE Journal of Power and Energy Systems 2022, 8(5): 1508-1518 https://doi.org/10.17775/CSEEJPES.2020.06610
Open Access | Issue | Published: 30 December 2021

CFD Analysis of an 800 kV HVDC Transformer Using Rapeseed Oil as the Cooling Fluid

Show Author's Information Edgardy M. Gutierrez Diaz,  Gaosheng Wei,  Liu Cui( )
Key Laboratory of Power Station Energy Transfer Conversion and System (Ministry of Education), School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
Department of Power Engineering, School of Electrical Engineering, Bicentenary University of Aragua, Turmero 2115, Venezuela
Keywords:
CFD analysis, cooling fluid, HVDC transformer, rapeseed oil
Cite this article:
Gutierrez Diaz EM, Wei G, Cui L. CFD Analysis of an 800 kV HVDC Transformer Using Rapeseed Oil as the Cooling Fluid. CSEE Journal of Power and Energy Systems, 2022, 8(5): 1508-1518. https://doi.org/10.17775/CSEEJPES.2020.06610
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Abstract Full text About this article

This study aims to analyze rapeseed oil’s effectiveness as a coolant of a high-voltage direct current (HVDC) converter transformer while comparing it with mineral oil. We employed a numerical model, assisted by Computational Fluid Dynamics (CFD) tools, to simulate the convective heat transfer inside a HVDC converter transformer, which is an oil-directed air forced (ODAF) type. The model seeks to obtain the temperature and velocity fields at the critical points of the fluid domain. The simulation domain reproduces a 2D cross-sectional model in the center of the structure. The results show that rapeseed oil requires more time to gain heat from the core and windings due to its lower thermal conductivity. However, the average temperature of rapeseed and mineral oils will not significantly differ once the channel temperature reaches a stable value. It indicates that the rapeseed oil can effectively replace mineral oil under the same heating conditions. Also, a slower flow of the rapeseed oil allows the fluid to smoothly enter the cooling channel. Therefore, the rapeseed oil cools these channels by pushing the fluid in them and absorbs heat from the sources earlier than mineral oil. The improvement in cooling indicates that rapeseed oil is better than mineral oil as a coolant and electrical insulating fluid for power transformers.


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About this article

CFD Analysis of an 800 kV HVDC Transformer Using Rapeseed Oil as the Cooling Fluid

Show Author's information Edgardy M. Gutierrez Diaz, Gaosheng Wei, Liu Cui( )
Key Laboratory of Power Station Energy Transfer Conversion and System (Ministry of Education), School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
Department of Power Engineering, School of Electrical Engineering, Bicentenary University of Aragua, Turmero 2115, Venezuela

Abstract

This study aims to analyze rapeseed oil’s effectiveness as a coolant of a high-voltage direct current (HVDC) converter transformer while comparing it with mineral oil. We employed a numerical model, assisted by Computational Fluid Dynamics (CFD) tools, to simulate the convective heat transfer inside a HVDC converter transformer, which is an oil-directed air forced (ODAF) type. The model seeks to obtain the temperature and velocity fields at the critical points of the fluid domain. The simulation domain reproduces a 2D cross-sectional model in the center of the structure. The results show that rapeseed oil requires more time to gain heat from the core and windings due to its lower thermal conductivity. However, the average temperature of rapeseed and mineral oils will not significantly differ once the channel temperature reaches a stable value. It indicates that the rapeseed oil can effectively replace mineral oil under the same heating conditions. Also, a slower flow of the rapeseed oil allows the fluid to smoothly enter the cooling channel. Therefore, the rapeseed oil cools these channels by pushing the fluid in them and absorbs heat from the sources earlier than mineral oil. The improvement in cooling indicates that rapeseed oil is better than mineral oil as a coolant and electrical insulating fluid for power transformers.

Keywords: CFD analysis, cooling fluid, HVDC transformer, rapeseed oil

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Publication history

Received: 09 December 2020
Revised: 27 March 2021
Accepted: 27 April 2021
Published: 30 December 2021
Issue date: September 2022

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© 2020 CSEE

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Acknowledgements

This work was supported in part by the National Natural Science Foundation of China under Grant No. 51806064 and No. 51776066.

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