| Title |
A Study on the Protective Relay Setting Rule for the Circulation Current Caused by ULTC Tap Mismatch between 765㎸ Transformer Banks |
| Keywords |
Current phase balance Relay ; Relay Setting Rule ; Circulation current ; ULTC Tap ; PSCAD |
| Abstract |
The 765(㎸) transformer is operated using two parallel tanks because of its high capacity. The protective relay (61) for the current phase balance of a 765(㎸) transformer would misoperate by excessively, circulation current of each tanks caused by a mismatch of ULTC Tap. In this paper, the phenomenon was analyzed, and the setting rules of relay for bank protection are studied. The result of analysis is verified by the simulation of 765(㎸) transformer with the Power Systems Computer Aided Design(PSCAD). Thereby an appropriate setting rule of the current phase balance relay is recommended. |