Complete characterization of utilization-voltage power system impedance using wideband measurement

Abstract

Inexpensive portable instrumentation is used to measure the impedance of an example utilization-voltage power system. With the power system in normal operation, line-to-neutral, line-to-ground, and neutral-to-ground impedances are measured over a bandwidth of 20 Hz to 24 kHz. The measured impedance is presented as resistance and inductance which vary with frequency. Based on the measurements, additional calculations are performed to find the resistance and inductance of every conductor in the system. This complete wideband characterization of power system impedance provides valuable data for power quality calculations.