公开(公告)号：US20210399545A1

公开(公告)日：2021-12-23

申请号：US17288640

申请日：2019-10-22

Applicant: ABB Power Grids Switzerland AG

Inventor： Obbalareddi Demudu Naidu ,  Preetham Venkat Yalla ,  Vedanta Pradhan ,  Nandkishor Kubal ,  Sachin Srivastava

IPC: H02H7/26 ,  G01R31/08

Abstract: The invention relates to protection from faults in a power transmission system having two or more transmission lines. Travelling waves are detected from a signal obtained with a measurement equipment associated with a bus of the power transmission system. Arrival times of a first peak of a first travelling wave, a second travelling wave and a third travelling wave, are detected from the signal. A value for line length is calculated from the arrival times and propagation velocity of the travelling wave in the corresponding transmission line. The calculated value is compared with an actual length of the corresponding transmission line, for determining if the fault is an internal fault or an external fault. According to the fault being one of the internal fault and the external fault, a signal for controlling a switching device associated with the corresponding transmission line is generated.