3Phadke A G. Thorp J. S. A new computer based flux - restrained current - differential relay for power transformer protection. IEEE trans on powerapparatus and system. 1983,102( 11 ) : 3624 - 3629.
4Kuniaki Yabe. Power differential method for discrimination between fault and magnetizin ginrush current in transformers[ J]. IEEE trans on power delivery. 1997,12(3) : 1109 - 1118.