Coordinated dispatch in multiple cooperative autonomous islanded microgrids

As various forms of renewable distributed generators (DGs) embedded in microgrids (MGs) often exhibit unstable characteristics, matching the generation to the demand whilst optimally utilizing the DGs is a non-trivial task. This paper investigates the optimal coordinated operation of multiple autonomous MGs and reveals the potential technical benefit. The proposed solution identifies the optimal network topologies and allocates the critical loads (CLs) to appropriate DGs based on the minimum spanning tree (MST) algorithm with power loss and reliability considerations. The non-critical loads (NLs) are determined to be supplied by the MGs based on the Linear Matrix Inequality (LMI) approach, which effectively improves the global utilization efficiency of DGs. Through the event-driven resource reallocation across multiple cooperative MGs, the dynamic balance between the power generation and demand can be attempted. The proposed approach is verified by using the IEEE 33-bus network model and its performance and scalability are further assessed through a large-scale IEEE 300-bus network scenario. The numerical results confirm that the suggested cooperative control of multiple MGs can effectively promote the capability of secure power supply to CLs, and simultaneously improves the global utilization efficiency of DGs significantly, even without any energy storage in the network. (C) 2015 Elsevier Ltd. All rights reserved.