Measurement of Nonsinusoidal Electric Power on Distributed Nonlinear Loads

The change in the electrical nature of the loads together with the loss of linearity are increasingly common phenomena in buildings, which requires special attention during the design phase of the electrical system in order to avoid problems in the management of reactive power flows and to better manage the power quality of the system. The presence of distributed nonlinear loads determines unusual behavior in terms of reactive power flux for the high harmonic distortion and for the capacitive behavior of the loads. Capacitive behavior is often evident when measuring reactive power in electrical systems feeding tertiary or commercial buildings, they feed reactive power at certain times of the day from a private network into a public network. The aim of this work is to analyze the performance of power systems feeding non-linear distributed loads with harmonic distortion and capacitive behavior, highlighting when this is real and when it is simply due to incorrect power factor measurements. If the behavior is truly capacitive, the problem can be solved by replacing the power factor correction systems with static compensators that are able to compensate reactive power for both capacitive and inductive behavior, working on all 4 quadrants. At the end, a real case study shows the unusual behavior of the distributed non-linear loads.