Probabilistic assessment of the impact of electric vehicles and nonlinear loads on power quality in residential networks

Abstract

This paper presents a probabilistic methodology to assess the power quality impact (harmonics and voltage unbalance levels) in low voltage residential networks with increased simultaneous integration of nonlinear loads and electric vehicles. The uncertain behavior of these loads is considered in the model by applying a probabilistic approach that accounts for their stochastic allocation and performance. In particular, different electric vehicle charging locations and modes of charge are assumed for the analysis of the electric car impact and weekly demand profiles are considered for the nonlinear loads. A Monte Carlo simulation is performed in order to obtain a probabilistic assessment of power quality with penetration levels of disturbing loads estimated for year 2030 for different penetration levels of electric vehicles in the system and including the interaction with photovoltaic generation. The methodology proposed is applied to the IEEE European Low Voltage network and to a larger 471-buses residential network and results are compared to EN50160 standard limits as the reference framework for low voltage power quality indices.