Nonintrusive identification of residential appliances using harmonic analysis

Abstract

The role of nonintrusive load monitoring (NILM) is to identify the operating schedules of individual appliancesand their power consumption from single-point electrical measurements. This paper discusses appliance load monitoringbased on the harmonic analysis of the steady-state current, which is specifically suited for identification of nonlinearappliances. The existing harmonic-based NILM methods have limited applicability due to the fact that their complexityincreases exponentially with the number of target appliances. In order to overcome this problem, this study suggests theuse of the step changes of current harmonic phasors as a feature for appliance detection. The key benefit of the proposedmethod is that only individual appliance signatures are needed to identify load activities, as opposed to the previousNILM methods that require load signatures with respect to all possible appliance combinations.