Flexible power management in MV networks with high penetration of electric vehicles

The envisaged increasing electrification of private transport (e.g. electric vehicles) will modify further the energy demands of customers. In this perspective, significantly more system monitoring and intelligent control will be needed in order to securely manage the electrical network ensuring optimal conditions meanwhile enabling active customer participation to system management through the provision of ancillary services. In this perspective Vehicle-to-Grid (V2G) technology will allow bi-directional flows of on-board batteries, thus enabling Electric Vehicles (EVs) participation in services for the grid support as flexible distributed energy storages. A rather interesting feature of the bidirectional EV battery charger is its inherent capability of providing reactive power without actually affecting the battery life, which makes it a valuable resource for the network as distributed reactive support. In this paper, EVs aggregators, such as residential and office and car parking, are considered to participate with other distributed resources to the network voltage regulation through a recently proposed novel network management procedure where participants are activated sequentially by means of a control token circulating around the responsive resources present in suitably defined network regulating areas. The token, generated and controlled by the network operator, represents a reactive power request and each customer-recipient may decide to provide only part of the required power variation, the total amount or nothing, depending on its own availability and economical benefit. Through a case study example, it is shown that, provided a suitable and flexible regulation scheme is adopted, EVs aggregators could meet responsively the grid power requirements and actively participate to the network voltage regulation.