Apply K-means Cluster Analysis to Perform Adaptive Protection IED in Microgrid

A microgrid consists of distributed energy resources (DERs) and loads. Due to the intermittent power generation of DERs and the changeable operation mode of microgrid, the magnitude and direction of fault currents are not fixed once a fault occurs in the microgrid. The protection scheme based on the traditional radial distribution system can no longer meet the protection requirements of microgrid. This study develops a microgrid protection management system (PMS) that follows the IEC 61850 protocol and integrates intelligent electronic devices (IEDs) and supervisory control and data acquisition (SCADA) platforms. Through the IED logic configuration and GOOSE mechanism, the circuit breaker tripping and blocking signals can be transmitted between IEDs to achieve protection of microgrid line, busbar and back-up protection. To solve the limitation of the number of IED setting group, this paper uses cluster analysis to group the microgrid operation status. The results can be used as the basis for IEDs setting groups. Based on the microgrid operation information collected by SCADA, the PMS can determine the setting groups of IEDs. The results show that the PMS can select the appropriate setting groups of IEDs under different microgrid operation situations to achieve the purpose of microgrid fault protection.