Current decomposition based on a double/multiple synochrouns reference frames and Fryze-Buchholz-Depenbrock theory for a non-islanded microgrid with a finite control set-model predictive controller: A comparative approach

In this work, load current in a multi-unit microgrid is decomposed into components. These components reflect the nature of total connected load at the point of common coupling (PCC) with the utility grid. Each unit (composed of distributed energy resources (DER), interfacing converter, and filtering elements), contributes to the total current fed by the microgrid. The current supplied by a unit is also decomposed into corresponding components as in case of the load current. The approach for decomposition is based on synchrouns reference frames that rotate at different frequencies. Current components obtained are in terms of symmetrical components with positive or negative sequence. Targeted components, embedded in ripple components are acquired by filtering action. A finite control set-model predictive controller is developed to control current supplied by each unit in a peer component approach. To validate the proposed double/multiple synchrouns reference frame (D/MSRF), decomposition is also carried out using the Fryze-Buchholz-Depenbrock (FBD) power theory. Results show the effectiveness of the proposed approach that require less calculation compared to FBD theory. In addition, the D/MSRF demonstrates the ability to decompose all types of encountered loads.