A comprehensive study of the techniques used in non-intrusive load disaggregation

Non-intrusive load monitoring (NILM) implies the measurement of input parameters, i.e. voltage and current in a single power line that supplies electricity to multiple appliances. A number of methods have been employed in previous work based on this load monitoring principle. The classification of loads is essential so as to ensure proper analysis of the power consumed. Load disaggregation comes handy for this purpose. Every appliance can be classified based upon its own unique signature. Hence, this paper is an effort conducted through the comprehensive study of various techniques used for load disaggregation and the benefits and the drawbacks associated with each technique. The techniques discussed in this paper employ approaches like active power measurement, harmonic analysis, wavelet transforms and graph signal processing. The experimental observations for various domestic loads are considered and evaluated.