A method to identify inrush currents in power transformers protection based on the differential current gradient

作者：Negreiros Alencar Raidson Jenner; Bezerra Ubiratan Holanda; Damasceno Ferreira Andre Mauricio

来源：Electric Power Systems Research, 2014, 111: 78-84.

DOI：10.1016/j.epsr.2014.02.009

• Differential current gradient
• Differential protection
• Inrush current
• Internal faults
• Power transformers
• Gradient vector

This paper presents a new methodology for distinguish between inrush currents and internal faults based on the differential current gradient. The scheme is based on calculating the differential current gradient vector angles in phases A-B-C at all points of the data Using statistical calculations, the inrush current is then identified, because its gradient vector behavior will be different in the case of a short circuit occurrence. The method effectiveness has been verified in several computational simulation cases using EMTP/ATP and MATLAB (R), analyzing situations of internal faults and inrush currents, including cases of sympathetic inrush in a power transformer, presenting highly satisfactory results.

• 出版日期2014-6