Method and apparatus for detection of short circuits by phase monitoring traveling wave signals

摘要

A method of and apparatus for the detection of short-circuits on lines operated with voltages and currents containing an alternating component, by detecting the temporal progression of the voltage and current at a measurement location in the form of measurement voltages and measurement currents. From the measurement voltage and measurement current or from magnitudes derived therefrom there are formed traveling wave signals of the form:PPa(t) = k. (u.sub.m + R.sub.w.i. sub.m) and PPb(t) = k. (-u.sub.m + R.sub.w.i.sub.m) PP wherein u.sub.m represents the measurement voltage and i. sub.m the measurement current or magnitudes derived therefrom, R.sub.w an impedance factor and k a freely introducable proportionality factor. There is monitored the mutual phase position of at least one respective frequency component of the oppositely moving traveling wave signals as a magnitude characterizing the condition of the line.