Household loads behavior and characterization in the context of power quality

Over the last few years, power electronics has been increasingly used in the electrical circuits of household loads. This type of load presents a non-linear behavior in terms of voltage and current and they are commonly represented as harmonic current sources. The analysis of the behavior of the harmonic currents produced by these loads is important for the mitigation of any disturbances caused by them. Additionally, the behavior of these loads during steady state voltage variations is of great relevance for a correct mathematical modeling. In this context, this paper aims to present both the harmonic characterization of household devices and its behavior during steady state voltage variations. As a result of this evaluation, the various loads studied will be characterized as constant impedance, constant power or constant current. Several experimental tests were carried out considering different types of household devices, which were submitted to 60 Hz steady state voltage variations. A programmable voltage source was used for this purpose. The experimental tests showed a variety of results, even considering the same type of device from different manufacturers.