Title :
Transformer differential protection using calculated power
Author :
Liping Wang ; Xiaoru Wang
Author_Institution :
Sch. of Electr. Eng., Southwest Jiaotong Univ., Chengdu, China
Abstract :
A new differential protection principle for transformer is proposed utilizing calculated power in this paper. It is able to discriminate between inrush and internal fault of transformers with large capacity and extra high voltage, preventing the maloperation due to magnetizing inrush. The calculated power is derived based on two-port network equivalent. An algorithm is presented that is practical for implementing in microcomputer relays. The effectiveness is proved by applying the proposed method to a Y/D-11 two-winding transformer rated 667MVA, 500 /10.5kV by via EMTDC simulation.
Keywords :
fault diagnosis; power transformer protection; relay protection; transformer windings; Y/D-11 two-winding transformer; apparent power 667 MVA; calculated power; inrush fault; internal fault; magnetizing inrush; microcomputer relays; transformer differential protection; two-port network equivalent; voltage 10.5 kV; voltage 500 kV; Automation; Power transformers; Relays; Surge protection; Surges; Windings; Calculated power; Differential protection; Magnetizing inrush; Transformer; Two-port network;
Conference_Titel :
Advanced Power System Automation and Protection (APAP), 2011 International Conference on
Conference_Location :
Beijing
Print_ISBN :
978-1-4244-9622-8
DOI :
10.1109/APAP.2011.6180428
