Total supply and accommodation capability curves for active distribution networks: Concept and model

Abstract This paper proposes the concept and model of total supply capability (TSC) curve and total accommodation capability (TAC) curve, which is a novel approach to assess the overall capability of an active distribution network (ADN) based on distribution system security region (DSSR). The TSC curve describes the full load supply capability while the TAC curve depicts the full distributed generation (DG) accommodation capability. For the TSC curve and the TAC curve, an ADN has both the upper curves and the lower curves, because both growth and reduction of either load or DG may result in security criticality, and form the upper and lower security boundaries, respectively. A simple test system and IEEE 33-node test system are used to demonstrate the proposed concepts and models. The TAC curve is compared with existing methods to show its advantages and applications. Additionally, it is found that supply capability and accommodation capability are dual; and the operational conditions of the ADN are divided by the four TSC/TAC curves.