Managing Distributed Energy Resources with Intertemporal Characteristics in Low-voltage Power Grids: A Single-period OPF Approach

The increasing installation of distributed energy resources (DERs) such as photovoltaics, electric vehicles, and heat pumps in residential premises causes voltage problems and asset overloading issues for distribution networks. To facilitate distribution system operators (DSOs) for efficient grid operations facing abundant DERs with intertemporal characteristics, this paper proposes a single-period optimal power flow (OPF)-based strategy for DSOs to generate optimized real and reactive power setpoints to manage such devices to resolve the network issues while considering end-users' comfort (e.g. thermal comfort, travelling comfort). The strategy relies on dynamic tradeoffs between different DERs based on their flexibility levels at each time step. Fairness considerations among end-users are also included through a quadratic objective function design. The proposed strategy is tested on a representative unbalanced low-voltage network including 195 buses and 182 single-phase household connections under different DER penetration levels. It is found in the case study that the proposed strategy can resolve the network issues while maintaining end-users' comfort even at a high DER penetration level of 75%. Compared to the mainstream rolling horizon control approach, the proposed strategy achieves comparable results concerning solving network issues and maintaining end-users' comfort while allowing significantly faster computation and less memory requirements.