Optimal dispatch scheme for DSO and prosumers by implementing three-phase distribution locational marginal prices

Abstract

Since the distribution system operator (DSO) cannot directly control prosumers with controllable resources, this study proposes an optimal dispatch method of using three-phase distribution locational marginal prices (DLMPs) as effective economic signals to incentivise prosumers' behaviours. In the proposed three-phase DLMP model, DLMPs for active power demand, active power output and reactive power output are calculated. To alleviate the imbalance, congestions and voltage violations in active distribution networks (ADNs), the DSO and prosumers should be coordinated. The authors develop such a coordinated control scheme for the DSO and prosumers, in which the DSO generates and broadcasts three-phase DLMPs as price signals to induce prosumers' behaviours. They prove that given the DLMPs as settlement prices, the optimal dispatch of the ADN will also maximise the surplus of prosumers. Therefore, the power output of rational prosumers will match the optimal dispatch, resulting in better operational conditions of ADNs. Then the three-phase imbalance, congestions and voltage violations will be well reduced. Numerical tests demonstrate the effectiveness of the proposed approach.