Barriers and Solutions for EVs Integration in the Distribution Grid

Abstract

The mass penetration of electric vehicles (EVs) could develop grid stability problems due to the increase of peak loads created by coincident charging factors. Smart charging is the control of the EV charging loads and has long been identified as a potential solution. Smart charging could also contribute to grid stability by mitigating the intermittent nature of renewable energy generation. This paper describes the current status of EV flexibility services at the distribution level. The analysis of the smart charging status is done considering the technological, economic and regulatory frameworks, and presenting what the different barriers of each of these aspects are. Additionally, the paper introduces the ACDC project (Autonomously Controlled Distributed Charger), which aims at developing an EV clustering method based on distributed smart charging control logic for flexibility services. For divulgation purposes, the scheduled test case scenario of the parking lot at the Technical University of Denmark is described. The paper concludes on some of the most relevant actions to overcome the most imminent barriers and to push further the rollout of EV charging infrastructure towards the target EV penetration planned by policymakers.

Distributed control of electric vehicle clusters for user-based power scheduling

“…Other research works concentrate on limited EV charging cluster including a semi-distributed charging approach introduced in [10], where the authors eliminate the existence of the central control entity by enabling one local controller to make charging decisions for all EVs, whereas the power allocation process is still settled in a centralized manner. An autonomously distributed control approach for EV parking lots management is described in [11], [12], where each charger controller operates independently with the common signal, yet only one plug of each charger controller can be activated, then forcing the rest EVs to cease charging. In practice, it is challenging for some EVs to restart the charging process once being interrupted.…”

Wind Based Charging via Autonomously Controlled EV Chargers under Grid Constraints

“…FTM services benefit the grid, and are managed by the DSOs and TSOs in order to ensure stability and security of supply. In [7], it is thoroughly explained what are BTM and FTM services. These types of grid services include prioritizing charging during off-peak times to assist in reducing peak loads, alleviating feeder congestion through charging power adjustments, and reducing wind power curtailment through the utilization of excess wind power production for the charging process [8].…”

Autonomously Distributed Control of EV Parking Lot Management for Optimal Grid Integration

“…Grid observability of already deployed chargers is the key to the development of smart charging on a large scale; therefore, deployed chargers should be coupled with smart meters to generate real usage data in different scenarios [10]. The design of mathematical models is the starting point for understanding the interaction between the clusters and the vehicles for behind-the-meter (BTM) services, and between the clusters and the grid for front-of-themeter (FTM) services [11]. In short, BTM services are a series of power and energy services that can be used to fulfill specific user's needs.…”

“…Some FTM services are congestion management, peak-shaving and voltage unbalance reduction. A more complete description of the grid services can be found in [11]. This paper focuses on the technical side of the development of smart charging, through the modelling of a smart charger based on a distributed control architecture.…”