Distributed Dispatch of Integrated Electricity-Heat Systems With Variable Mass Flow

Authors：Zheng, Weiye^*; Zhu, Jizhong; Luo, Qingju

Source：IEEE Transactions on Smart Grid, 2023, 14(3): 1907-1919.

DOI：10.1109/TSG.2022.3210014

• Pipelines
• Resistance heating
• Heat pumps
• Water heating
• Cogeneration
• Heat transfer
• Couplings
• Integrated energy system
• combined heat and power generation
• variable mass flow
• mixed-integer nonconvex programming
• distributed optimization

The constant mass flow assumption has dominated distributed dispatch of integrated electricity-heat systems (IEHSs), which ensures the simplicity of decomposition while incurring opportunity costs. In contrast, a heat operation strategy with variable flow and variable temperature (VF-VT) enhances flexibility and optimality. However, VF-VT renders the IEHS dispatch problem into a mixed-integer nonlinear bi-level nested program, which leaves a critical yet unresolved challenge for distributed autonomous dispatch. Therefore, this paper proposes a two-stage alternating procedure embedded with sequential equivalent techniques. A feasible initial point is obtained in the first stage, and the total costs are minimized thereafter. In each iteration, the heat sector optimizes both hydraulic and thermal states based on a surrogate model, and submits the heat equivalent to the electricity sector; the electricity sector solves the reduced IEHS dispatch problem and then updates the boundary. The feasibility is proved theoretically, while numerical tests validate the effectiveness.