Research of the improved time difference method to distinguish TA's saturation

In differential protection, the reliability of protection is influenced seriously by the TA's transform error when TA saturated. This paper proposes the improved time differential method of detecting TA saturation based on the analysis of the reasons of TA saturation and the features of saturated current. The result of simulation shows that the new method can detect TA saturation correctly and sensitively, thus the maloperation of protection is avoided.