A multi-agent based protection in distribution networks including distributed generations

This paper proposes a strategy for protection coordination in distribution networks with DGs penetration. The main objective of the present work is to employ the potential of Multi-Agent Systems (MASs), which have recently been given considerable attention in the context of smart grids. A modified scheme is proposed to minimize the number of agents while preserving the necessities of protection coordination under different contingencies. A new structure is defined for relay agent (RA) to operate in centralized or decentralized modes. Each RA contains communication and protection units, to detect an appropriate mode according to the required time to clear the fault and maintain coordination with other agents. IEC-61850 standard including GOOSE and SMV protocols used to send necessary commands and share data. The proposed protection scheme has 8 stages, which removes the fault from the network with the help of services and functions defined on the proposed structure of the relay agent. These steps include gathering network information, sending commands, and updating relay settings. In this regard, impacts of DGs are analyzed to show how they would change the operation of protective relays and their corresponding zones. Results of this research ensure the proper performance of protective devices taking into account appropriate settings and configurations.