Criteria for inter-winding fault detection within power transformers

Abstract

Power transformers are highly valued power system's elements, transformers failure may lead to high scale system's operations disruption and heavy economic losses. This is the main reason for power transformer protection requirements to be so high. Sensitivity level is a key element in inter-winding faults detection. Incomplete winding faults that occur in the multi-wire transformer windings, when multiple parallel wires form a coil, are very hard to detect, this is why it is the most challenging issue for the differential protection. This paper presents the development of a criteria for inter-winding fault detection.