Application of reduced scale tests to improve the thermal performance of high-voltage substation connectors

ABSTRACT

The thermal behavior of high-voltage substation connectors is a critical aspect that must be considered during the design stage. Most research about the thermal performance of substation connector devices is based on full-scale models. This paper proposes a downscaling method to evaluate the thermal performance of reduced scale substation connectors. The theoretical results attained in this paper were validated by means of FEM simulations and experimental tests. Reduced scale simulation and testing will be an essential tool for assessing the thermal performance of substation connectors and other electrical equipment during the design and validation stages.

KEYWORDS:

• Scaling
• thermal model
• transient analysis
• finite element method
• short-circuit
• connector

Acknowledgments

The authors would like to thank and SBI Connectors for providing the equipment to perform the experimental tests. They also thank the Spanish Ministry of Economy and Competitiveness and Generalitat de Catalunya for the financial support received under projects RTC-2014-2862-3 and SGR 101 2014-2016, respectively

Nomenclature

$\dot{Q}$	=	Rate of energy with respect to time (W)
q	=	Heat flux density (W/m3)
E	=	Electric field strength (V/m)
j	=	Current density (A/m2)
Cp	=	Specific heat (J/(kg·K))
k	=	Coefficient of thermal conductivity (W/(m·K))
m	=	Mass (kg)
ρ	=	Mass density (kg/m3)
ρe	=	Electrical resistivity (Ω·m)
αe	=	Temperature coefficient of the resistivity (1/K)
R	=	Electrical resistance (Ω)
I	=	Electrical current (A)
L	=	Characteristic length (m)
A	=	Cross sectional area normal to the electrical current (m2)
V	=	Volume (m3)
h	=	Convective heat transfer coefficient (W/(m2·K))
ε	=	Dimensionless emissivity number
σ	=	Stefan-Boltzmann constant (W/(m2·K4))
T	=	Absolute temperature (K)
To	=	Absolute reference temperature (K)
T∞	=	Absolute air temperature far from the analyzed objects (K)
n	=	Scaling factor (-)

Additional information

Funding

This work was supported by the Departament d’Innovació, Universitats i Empresa, Generalitat de Catalunya [2017 SGR 967]; Spanish Ministry of Economy and Competitiveness [RTC-2014-2862-3].