Transformers Magazine, Vol. 9 No. 3, 2022.
Izvorni znanstveni članak
Investigating core influence on transformers insulation diagnostics
Roberto Borges
Ronald D. Hernández
Waldemar Ziomek
Ryan Plater
Sažetak
In a healthy power transformer, the power factor (PF) of the low-voltage winding insulation to the ground (CL) is expected to be less than 0.5 %. In recent cases, the CL PF measured during the factory testing exhibited high values close or above 0.5 %. Investigations have determined that
the issue might be related to a higher than usual core steel interlaminar resistance, occurring due to a combination of shorter burrs and higher non-uniform insulation resistance between laminations. This article describes the phenomena and proposes a test protocol to differentiate the
problem from other issues that cause high CL PFs, such as moisture or contamination / deterioration of the insulation.
Ključne riječi
core interlaminar resistance, insulation, insulation power factor, transformer diagnostics
Hrčak ID:
280336
URI
Datum izdavanja:
8.7.2022.
Posjeta: 899 *