Portable Impedance/Reflected Power Meter for power-line carrier applications

Abstract

Portable Impedance/Reflected Power Meter consists of an integrated system with 1) a portable circuit designed to make voltage and current measurements in a power-line carrier circuit, 2) a digitizer (NI USB-5132) capable of sampling signals in the frequency range of 30 kHz to 500 kHz, and 3) a LabVIEW application configured to acquire the signal from the digitizer to a computer and perform computation to calculate the impedance of the load connected to the portable circuit and also the reflected power from the measured impedance. The functionality of the integrated meter was tested in lab using simulated loads, and on a PLC circuit on a 500 kV transmission line. The measurements were comparable to a meter used by utilities to make similar measurements. The paper provides an economical, portable solution that takes advantage of the processing power of a computer.