Carbon-Constrained Congestion Management of Transmission Networks with Demand Response

To address transmission congestion resulting from branch capacity constraints, this study proposes a novel transmission congestion management approach with leveraging demand-side flexibility resources. A carbon-constrained bi-level optimization model incorporating demand response is developed, accounting for the low-carbon characteristics of generation units. At the transmission network optimization layer, the optimal generator dispatch schedule and locational marginal prices are determined by minimizing the combined generator operating and carbon emission costs. At the demand-side management layer, loads are dynamically scheduled in response to the locational marginal prices set by the transmission network optimization layer, with the objective of minimizing electricity procurement costs. This bidirectional interaction mechanism enables the transmission and demand side to jointly mitigate transmission congestion. Case studies on a modified IEEE 39-bus system demonstrate the effectiveness of the proposed model in relieving branch overloads, verifying the synergistic benefits of coordinated scheduling in enhancing grid hosting capacity and reducing carbon emissions.