Optimization Strategy of Hybrid AC-DC Power Supply for Regional Integrated Energy System

The establishment of regional integrated energy system (RIES) can make various forms of energy complement each other, and improve the performance of the whole energy utilization system in new energy elimination, comprehensive energy utilization, environmental cost and overall operating efficiency. This paper proposes an optimization model of on-grid hybrid AC-DC power supply for multiple energy system, which realizes the AC-DC flexible conversion of electric energy and comprehensive utilization of multi-energy. The structural diagram of economic dispatch of a multi-energy system is first built, and the corresponding mathematical models for each module are established, analyzing comprehensively characteristics of the AC-DC power supply in regional integrated energy systems (RIES), combined with the heating characteristics, the charging & discharging characteristics of the energy storage device. Then, the economic model of on-grid hybrid AC-DC operation is established, considering the constraints such as energy balance, the operating of each device, and the environmental cost with the objective of minimizing total operating cost. Further, based on GAMS optimization software, the optimal output and total operating cost in the traditional AC grid-connection model and in the on-grid hybrid AC-DC model are obtained within the dispatching cycle. Finally, the comparative results demonstrate that the proposed model can reduce operating costs, harmful gas emissions and coal consumption effectively.