Cooperative voltage control of distributed generation and grid connected converter in DC microgrid

Abstract

Many researches on a voltage control method in a DC microgrid has been studied, but almost of them are only focused on control in small scale microgrid such as a building power grid. Whereas it is expected a DC microgrid becomes larger with respect to increasing of a DC energy source and a power load, thus a new control scheme is required for middle or large scale DC microgrids. This paper analyses a voltage drop problem in a radial DC microgrid and proposes a cooperative voltage control scheme with a distributed generation (DG) and a grid connected converter (GCC). The voltage control method with DG and GCC is proposed to minimize an operation cost in DC microgrid and additionally an optimal DG allocation algorithm is proposed for minimization of DG capacity. And finally, the proposed methods are verified by simulation using PSCAD/EMTDC.