公开(公告)号：US11374395B2

公开(公告)日：2022-06-28

申请号：US16729280

申请日：2019-12-27

Applicant: Huawei Technologies Co., Ltd.

Inventor： Guoqing Zhang ,  Andreas Stiedl ,  Zhiming Xiao ,  Michael Tabakov

IPC: H02H3/00 ,  H02H3/16 ,  H02J13/00 ,  G01R31/52 ,  H02H1/00 ,  G01R31/50

Abstract: A remote power unit for providing direct current power to a remote power receiver in a direct current power system is provided. A residual current protection circuit comprises a first switch, which opens a positive voltage rail, and a second switch, which open a negative voltage rail. A first current sensor measures a first residual current between the first switch and the remote power receiver, while the first switch is closed and the second switch is opened. A second current sensor measures a second residual current between the second switch and the remote power receiver, while the second switch is closed and the first switch is open. A controller detects a residual current event, if the first residual current and/or the second residual current are above a residual current threshold.