公开(公告)号：EP1820034B1

公开(公告)日：2009-09-23

申请号：EP05803993.4

申请日：2005-11-18

申请人： Powersense A/S

发明人： BJØRN, Lars, Nørgaard

IPC分类号： G01R31/02 ,  H02H3/52 ,  H02J13/00

CPC分类号： H04W4/14 ,  G01R1/00 ,  G01R15/246 ,  G01R19/2513 ,  G01R31/025 ,  G01R33/0322 ,  H04L67/12

摘要： The present invention relates to a monitoring system for detecting earth faults in an electrical power supply grid. The system may comprise a plurality of monitoring devices mounted in a number of monitoring locations, each of the monitoring devices may include a detector for detecting level of harmonics in the electrical power. The level of harmonics is preferably detected in a specific frequency range. The monitoring devices may further include a memory device for storing a harmonics reference value and may still further include a processor for comparing the level of harmonics with the reference level. The monitoring device may even still further include a communication device for transmitting an alarm provided the level of harmonics is above the reference level for a specific period of time.