Method for continuous real-time detection of unintentional isolated operation during supplying of current signal into low voltage system, involves carrying out detection of frequency range and/or calculation of impedance in real-time

摘要

The method involves detecting a frequency range of a main signal overlapped with an auxiliary signal for determining a frequency spectrum of the main signal, where the frequency range comprises a main frequency range and an auxiliary frequency range. Impedance is calculated from magnitudes of current (I) and voltage (U) of the auxiliary signal in the auxiliary frequency range of the frequency spectrum such that scanning of the calculated impedance takes place over time, where the detection of the frequency range and/or the calculation of the impedance is executed continuously in real-time. An independent claim is also included for a device for continuous real-time detection of unintentional isolated operation.