Validated transient heat-transfer model for underground transformer in rectangular vault

Julien Sandraz, Francisco De Leon, Joseph Cultrera

Research output: Contribution to journalArticle

Abstract

A new thermal model for underground transformers is proposed in this paper. The model takes the following important characteristics of the transformer installation into account: rectangular shapes; coil and core arrangement; orientation-based convection models for air (vertical, horizontal-upward, and horizontal-downward heat flows); and turbulent or laminar flow regime. The resulting coupled set of differential and algebraic nonlinear equations is solved simultaneously, providing a robust and fast solution that can help design transformers. The model has been validated against three transformers with different dimensions installed in different vaults with onsite measurements. The average absolute difference between the simulated and measured temperatures over several months is typically less than 4°C. A parameter sensitivity study shows the critical importance of the proper estimation of the full-load heat loss and the ambient soil temperature.

Original languageEnglish (US)
Article number6516999
Pages (from-to)1770-1778
Number of pages9
JournalIEEE Transactions on Power Delivery
Volume28
Issue number3
DOIs
StatePublished - 2013

Fingerprint

Heat transfer
Heat losses
Laminar flow
Nonlinear equations
Turbulent flow
Soils
Temperature
Air
Convection
Hot Temperature

Keywords

  • Distribution transformers
  • heat-transfer transients
  • predictive maintenance
  • thermal analysis
  • thermal circuit

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Energy Engineering and Power Technology

Cite this

Validated transient heat-transfer model for underground transformer in rectangular vault. / Sandraz, Julien; De Leon, Francisco; Cultrera, Joseph.

In: IEEE Transactions on Power Delivery, Vol. 28, No. 3, 6516999, 2013, p. 1770-1778.

Research output: Contribution to journalArticle

@article{b605bf54e5ea45438febb047af1b9a92,
title = "Validated transient heat-transfer model for underground transformer in rectangular vault",
abstract = "A new thermal model for underground transformers is proposed in this paper. The model takes the following important characteristics of the transformer installation into account: rectangular shapes; coil and core arrangement; orientation-based convection models for air (vertical, horizontal-upward, and horizontal-downward heat flows); and turbulent or laminar flow regime. The resulting coupled set of differential and algebraic nonlinear equations is solved simultaneously, providing a robust and fast solution that can help design transformers. The model has been validated against three transformers with different dimensions installed in different vaults with onsite measurements. The average absolute difference between the simulated and measured temperatures over several months is typically less than 4°C. A parameter sensitivity study shows the critical importance of the proper estimation of the full-load heat loss and the ambient soil temperature.",
keywords = "Distribution transformers, heat-transfer transients, predictive maintenance, thermal analysis, thermal circuit",
author = "Julien Sandraz and {De Leon}, Francisco and Joseph Cultrera",
year = "2013",
doi = "10.1109/TPWRD.2013.2260183",
language = "English (US)",
volume = "28",
pages = "1770--1778",
journal = "IEEE Transactions on Power Delivery",
issn = "0885-8977",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "3",

}

TY - JOUR

T1 - Validated transient heat-transfer model for underground transformer in rectangular vault

AU - Sandraz, Julien

AU - De Leon, Francisco

AU - Cultrera, Joseph

PY - 2013

Y1 - 2013

N2 - A new thermal model for underground transformers is proposed in this paper. The model takes the following important characteristics of the transformer installation into account: rectangular shapes; coil and core arrangement; orientation-based convection models for air (vertical, horizontal-upward, and horizontal-downward heat flows); and turbulent or laminar flow regime. The resulting coupled set of differential and algebraic nonlinear equations is solved simultaneously, providing a robust and fast solution that can help design transformers. The model has been validated against three transformers with different dimensions installed in different vaults with onsite measurements. The average absolute difference between the simulated and measured temperatures over several months is typically less than 4°C. A parameter sensitivity study shows the critical importance of the proper estimation of the full-load heat loss and the ambient soil temperature.

AB - A new thermal model for underground transformers is proposed in this paper. The model takes the following important characteristics of the transformer installation into account: rectangular shapes; coil and core arrangement; orientation-based convection models for air (vertical, horizontal-upward, and horizontal-downward heat flows); and turbulent or laminar flow regime. The resulting coupled set of differential and algebraic nonlinear equations is solved simultaneously, providing a robust and fast solution that can help design transformers. The model has been validated against three transformers with different dimensions installed in different vaults with onsite measurements. The average absolute difference between the simulated and measured temperatures over several months is typically less than 4°C. A parameter sensitivity study shows the critical importance of the proper estimation of the full-load heat loss and the ambient soil temperature.

KW - Distribution transformers

KW - heat-transfer transients

KW - predictive maintenance

KW - thermal analysis

KW - thermal circuit

UR - http://www.scopus.com/inward/record.url?scp=84880076653&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84880076653&partnerID=8YFLogxK

U2 - 10.1109/TPWRD.2013.2260183

DO - 10.1109/TPWRD.2013.2260183

M3 - Article

VL - 28

SP - 1770

EP - 1778

JO - IEEE Transactions on Power Delivery

JF - IEEE Transactions on Power Delivery

SN - 0885-8977

IS - 3

M1 - 6516999

ER -