Distributed resources coordination inside nearly-zero energy buildings providing grid voltage support from a symmetrical component perspective

Abstract

In this work, the authors propose a new coordination method for smart distribution networks (SDN) with nearly-zero energy buildings (nZEB). The proposed coordination procedure considers a central controller that runs a state estimation of the grid and calculates the optimum set-points for the buildings. Inside each building, the building management system (BMS) manages the converters used by the dispatchable generators (DG), the renewable generators (RG) and the energy storage system (ESS) to fulfil (as far as possible), the central controller request.In the paper, the unbalanced behaviour of the grid is considered, so the optimum references for the symmetrical component currents in the converters are calculated. The proposed method reduces the network unbalance and the total losses. In addition, buildings with energy surplus can support other neighbours with energy deficit. The present paper is focused on how the BMS calculates the optimum references for all converters placed inside each building. The main contribution of the paper is the use of the symmetrical component approach at building level in order to generate the best references for all converters inside the building.