Apparatus e.g. digital circuit analyzer for measuring alternating current (AC) voltage and AC current or AC measured variables in conductor, determines integrator signal using Rogowski coil signal and current signal

摘要

The apparatus (1) has current channel (2) and voltage channel (3) for detecting current signal and voltage signal of conductor respectively. An analog-to-digital converter (5) is provided to convert the voltage signal into discrete-time voltage signal. The current signal is proportional to Rogowski coil voltage. Another analog-to-digital converter (7) is provided to convert Rogowski coil voltage into discrete-time Rogowski coil signal. The integrator signal is determined using Rogowski coil signal and current signal. A phase locked loop (8) is arranged in the voltage channel.