© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., The number of electric vehicles connected to the grid is growing constantly due to environmental and regulatory issues. Conventionally these vehicles work as variable loads, although using them as distributed generators is a promising future functionality, known as vehicle to grid concept. Using vehicle to grid capacities to support the grid during voltage sags, emulating Low Voltage Ride Through protocols, have been studied extensively, also in the field of islanded microgrids based on power electronics converters. This work proposes a change of paradigm for low voltage islanded microgrids, where the network impedances are mainly resistive. Instead of injecting reactive currents during the sag, this work proposes the injection of unbalanced active currents with two main objectives. First, support the microgrid voltage prioritizing in the reduction of voltage unbalance to avoid over voltages in the less faulty phases. And second, collaborate in the active power injection with the distributed generators to supply the over currents that demands the system during short circuits which produce voltage sags. Selected simulation results demonstrate the effectiveness of the control proposal., This publication is part of the project I + D + I RTI2018–100732 – B – C22, financed by MCIN / AEI / 10.13039 / 501000011033 and FEDER “Una manera de hacer Europa"., Peer Reviewed, Postprint (author's final draft)

This paper presents a real-time control strategy for electric-vehicle based microgrids to mitigate voltage sags in large parking lots. It is programmed into the digital processors of the battery chargers and consists on the injection of reactive current by both positive- and negative sequence components. As main characteristics, it should be noted that the control strategy can function correctly during both balanced and unbalanced voltage sags and is an economical solution since it does not require the inclusion of additional power converters to improve power quality. This study also looks at the ability to mitigate voltage sags based on the number of parked vehicles., This work is part of the project I+D+i RTI2018-100732-B-C22, funded by MCIN/AEI/10.13039/501000011033 and FEDER “Una manera de hacer
Europa (A way to make Europe)"., Peer Reviewed, Postprint (author's final draft)

This paper presents a real-time control strategy for electric-vehicle based microgrids to mitigate voltage sags in large parking lots. It is programmed into the digital processors of the battery chargers and consists on the injection of reactive current by both positive- and negative sequence components. As main characteristics, it should be noted that the control strategy can function correctly during both balanced and unbalanced voltage sags and is an economical solution since it does not require the inclusion of additional power converters to improve power quality. This study also looks at the ability to mitigate voltage sags based on the number of parked vehicles., This work is part of the project I+D+i RTI2018-100732-B-C22, funded by MCIN/AEI/10.13039/501000011033 and FEDER “Una manera de hacer
Europa (A way to make Europe)"., Peer Reviewed

© 2022 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works., The number of electric vehicles connected to the grid is growing constantly due to environmental and regulatory issues. Conventionally these vehicles work as variable loads, although using them as distributed generators is a promising future functionality, known as vehicle to grid concept. Using vehicle to grid capacities to support the grid during voltage sags, emulating Low Voltage Ride Through protocols, have been studied extensively, also in the field of islanded microgrids based on power electronics converters. This work proposes a change of paradigm for low voltage islanded microgrids, where the network impedances are mainly resistive. Instead of injecting reactive currents during the sag, this work proposes the injection of unbalanced active currents with two main objectives. First, support the microgrid voltage prioritizing in the reduction of voltage unbalance to avoid over voltages in the less faulty phases. And second, collaborate in the active power injection with the distributed generators to supply the over currents that demands the system during short circuits which produce voltage sags. Selected simulation results demonstrate the effectiveness of the control proposal., This publication is part of the project I + D + I RTI2018–100732 – B – C22, financed by MCIN / AEI / 10.13039 / 501000011033 and FEDER “Una manera de hacer Europa"., Peer Reviewed