초록 열기/닫기 버튼

In this paper, a negative-sequence current differential algorithm using asynchronous positive-sequence voltages is proposed to solve the problem that the negative-sequence current differential algorithm using asynchronous negative-sequence voltages may cause malfunction due to the small magnitude of the negative-sequence voltages. This algorithm using asynchronous negative-sequence voltages is an algorithm for solving erroneous operation due to effects of fault resistance and time synchronization problems of current differential algorithm. And this paper explains why positive-sequence voltage was used, and difference in detection of fault direction at relay point of each algorithm. And then, Each algorithm is tested in an IEC-61850 based centralized protection system environment configured using Real Time Digital Simulator and IEDs(Intelligent Electronic Devices), which are implemented with the MMS-EASE Lite library and Evaluation Modules. The test results show that only the proposed algorithm operate successfully, and therefore the proposed algorithm is appropriate for transmission line backup protection.