A method for the detection and location of low and high resistance ground faults in electrical supply networks

摘要

A method for the detection and location of low and high resistance ground faults in electrical power supply circuits, characterised by the following steps:A) at the point in time t₁ the waste material takes place in each case a measurement and calculation of the sums admittance with respect to ground, as well as a division of the asymmetry on the individual conductors - earth admittances, comprising the steps of:a) feeding a composite current in the zero phase-sequence system of the correction network.b) wherein the current from the superimposition of the current with the amplitude i_f1 and the frequency f₁ and of the second current with the amplitude i_f2 and the frequency f₂ which is composed of a.c) measuring the displacement voltages U_{0 _ f1 _ x} and U_{0 _ f2 _ x} according to known methods for the two frequencies the output x or on the bus bar with unique allocation to the outlet x.d) measuring the sums currents I_{Σ _ f1 _ x} and I_{Σ _ f2 _ x} according to known a method according to magnitude and angle for the two frequencies, the outlet x. the angle relates to the..