Coordinated Voltage Support with Reactive Power from High-power Charging Stations for EVs

Abstract

High-power charging stations have recently drawn the attention of many researchers and electric vehicle (EV) infrastructure industries. However, the installation of fast chargers at various corridors of highways and cities can cause high peak loads and voltage deviations in distribution networks. In addition, the usage patterns can vary drastically from one fast charging station to another at any given instant. However, future highpower charging stations could be able to operate in any of the four P-Q quadrants. Thus, high-power charging stations for EVs have the capability of serving as a flexibility resource and minimising voltage deviations. This research introduces a method for mitigating voltage quality problems in distribution network by effective utilisation of the reactive power potential from fast charging stations. The suggested method introduces a secondorder cone programming approach that is validated on the IEEE 69 bus distribution system. The performance of the method is analysed in a case study with measured charging profiles from real high-power charging stations in Norway.

Economic Assessment of Integrating Fast-Charging Stations and Energy Communities in Grid Planning

“…The goal of an FCS is to provide to as much active power as possible to charging EVs. However, reactive power can be controlled without interfering with EV charging [21]. In the previous studies [21] [22], a DSO operational model was proposed for calculating the optimal reactive power Q for minimising voltage deviations.…”

“…However, reactive power can be controlled without interfering with EV charging [21]. In the previous studies [21] [22], a DSO operational model was proposed for calculating the optimal reactive power Q for minimising voltage deviations. However, in this work, a simpler representation of this active measure can be used instead of an optimization model that assumes information from both the FCS operator and the DSO for the operational planning.…”

“…Since the majority of the lines in the longest lateral of the grid under study have an R/X ratio of less than 5, the maximum reactive injection of FCS converters may be sufficient for voltage improvement. This means that FCSs indirectly contribute to grid support without any signals from DSOs unlike in [21] [22]. In this work, it is assumed that information about expected aggregated charging load profiles and the aggregated FCS converter capability curve is provided to the DSO's investment model.…”

Análise de Estações de Recarga Rápida de Veículos Elétricos como Compensadores Dinâmicos de Reativos

“…Em (Falahi, H.M. Chou, & Butler-Purry, 2013;Rana & Torsaeter, 2021), o problema de minimização de desvio de tensão é incorporado às simulações de fluxo de carga, sendo que o primeiro estudo abrange o problema de forma local, enquanto o último aborda o problema globalmente. Ambos os trabalhos consideram que a operação das ERs como CDRs não envolve as baterias dos VEs e não afeta a operação destas estruturas, exceto pelo pequeno consumo adicional de potência ativa utilizada para manutenção da tensão sobre o capacitor do link CC; contudo, ambos os trabalhos consideram este valor desprezível.…”