Discussion on reliability and power quality in the smart grid: A prosumer approach of a time scalable index

Abstract

This article presents a discussion related to the measurement techniques of the electric energy quality within the smart grid (SG) context, and considering the producer-consumer (prosumer) approach. It establishes the basis where new power quality (PQ) indexes should be proposed, in order to complement the current recommendations regarding consumer dissatisfaction indexes (CDI) on which the network should be assessed and planned. Indeed, the current indices only consider the number of interruptions and the time during which they occur, and do not take into account neither the type nor the non-linear loads (distributed energy resources, DER) connected to the SG, which are giving rise to new kinds of transients coupled to the electrical power supply signal. In this sense, the paper provides reasons on why temporal evolution of energy and its deviation from the contractual specifications should be monitored and assessed, with the goal of making real-time decisions. Based on advanced statistical signal processing, forecasting methods and artificial intelligence, this focus conveys the conclusive need for a dual measurement index of PQ reliability, on the basis of dynamic temporal scalability, and time-space compressions. A practical example is outlined.