Control and Operation of the Proposed Interlinking Converter in a DC-AC-DC Hybrid Microgrid Based on the Proposed Modes of Operation

Regarding improvement and development of new energy resources, hybrid distributed production resources are also being extended. Hybrid network includes AC microgrid and DC microgrid. These microgrids connect to each other via power electronic converter interface. DC microgrid having lower voltage level feeds loads that are more sensitive. To this aim, it connects to DC microgrid having higher voltage via an isolated DC/DC converter. Each microgrid's resources are controlled so it is possible to operate power sharing using droop method. The mentioned interlinking converter can transfer power in both directions and will operate either in voltage control or power control mode. In this paper we propose a method in which the interlinking converter will take part in microgrid power sharing alike to one the sources of each desired side. For the interlinking converter, two control loops are designed, one for current control and the other one for voltage control, and resonant controller is used in both loops. DC side resources are considered to be converter-based boost controlled resources. Double-lead integral controller will be designed for DC converter-based resources. AC microgrid resources are also considered to be converter-based resonant controlled resources. Simulation will be done in MATLAB, and sample network and defined scenarios will be tested considering operation mode on the network to investigate the performance of interlinking converter.