Hosting Capacity of an Australian Low-Voltage Distribution Network for Electric Vehicle Adoption
Joshua Then, Ashish P. Agalgaonkar, Kashem M. Muttaqi
Abstract
Electric vehicle charging applies a notable strain on the electricity network due to the large load produced. This article will examine these charging loads and their effect on the traditional electricity network using hosting capacity to evaluate this impact. Three indices are proposed to quantitatively describe the hosting capacity. The voltage deviation index describes voltage changes in the network due to variations in loading. The substation power delivery index analyses power flow through a substation as a ratio of its rated capacity to determine its utilisation and if it is overloaded. The current unbalance factor measures phase unbalance in the network using sequence currents. A case study of a distribution network in Australia was performed to examine network capacities and peak loads. A futuristic prediction is made to evaluate how the network will cope with an increase in loads due to electric vehicle charging. Simulations were performed in a series of scenarios including no electric vehicle adoption, adopting electric vehicles as a second vehicles, one electric vehicle per household, and electric vehicle charging with rooftop solar panels. The results showed that the introduction of charging increased voltage sag and power delivery, as indicated by the indices, with some substations experiencing overloading and excessive voltage sag. These issues were mitigated by distributing electric vehicle charging throughout the day and introducing rooftop solar panels. The results of this study can be used to estimate the increase in network capacity required to accommodate for the increase in charging loads.