Method and detection device for detecting a high-impedance ground fault in an electrical energy supply network with a grounded neutral point

摘要

#$%^&*AU2018241129B220200528.pdf#####METHOD AND DETECTION DEVICE FOR DETECTING A HIGH-IMPEDANCE GROUND FAULT IN AN ELECTRICAL ENERGY SUPPLY NETWORK WITH A GROUNDED NEUTRAL POINT ABSTRACT Method and detection device for detecting a high-impedance ground fault in an electrical energy supply network with a grounded neutral point The invention relates to a method for detecting a high-impedance ground fault in an electrical energy supply network (12) with a grounded neutral point, in which a test signal is fed with a detection device (10) into the energy supply network (12), wherein the test signal has a frequency which differs from the network frequency of the energy supply network (12), and the presence of a high-impedance ground fault is inferred on the basis of a measuring signal produced by the test signal. In order to enable a reliable detection, with low equipment costs, of high-impedance ground faults in energy supply networks with a grounded neutral point, it is proposed that a three-phase test signal is fed into the phase conductors of the energy supply network (12) as a test signal, a measuring signal which indicates the displacement voltage of the test signal is generated with the detection device (10), the displacement voltage is compared with a threshold value using a test device (15) of the detection device (10), and the presence of a high-impedance ground fault is detected if the displacement voltage exceeds the threshold value. The invention also relates to a correspondingly designed detection device (10).1/3 192 111 Tj1 , 13 ~ 10 15 16! Fig. 1