Research On Planning And Optimal Operation Of Regional Multi-energy Systems

The proposal of the "dual-carbon target" has promoted the development of my country’s energy system towards green,high-efficiency,and integrated development.The regional multi-energy system breaks through the barriers of the traditional energy system,promotes the coupling and complementarity of multiple energy sources such as cooling,heating and power,and plays an important role in achieving the "dual carbon goal".Due to the heterogeneity of different energy characteristics in the regional multi-energy system,how to fully balance economy and environmental protection,rationally plan system equipment configuration and optimize operation,has important research significance for achieving carbon peak and carbon neutrality.Based on the above background,this paper in view of regional energy system planning and optimal operation conducted in-depth research,done work is as follows:(1)Modeling of multivariable system units based on energy busbars.Analysis of the operational characteristics of the core controllable device of the regional multivariate system,the detailed mathematical model of the electrical energy bus and the thermal energy busbar,laid theoretical foundation for the planning and optimization of regional multi-energy systems.(2)The multi-objective planning model of regional multi-energy system under the background of low carbon was established.A two-level planning method for regional multi-energy system is proposed,which considers economy and environmental protection simultaneously.The upper level model considers economy to minimize operation cost,while the lower level model considers environmental protection to minimize carbon emission.Formulation and decomposition(R&D)is adopted to solve the planning model.The numerical example shows that the model can avoid the influence of different weights when the multi-objective model is transformed into a single objective model,and the global optimal solution of the system is obtained.(3)A regional multi-energy system planning model considering thermal inertia is established.Based on the nodal method,the heat network characteristics are modeled,and the heat load models including building heating and domestic hot water are established.On this basis,a regional multi-energy optimization planning model based on MILP(Mixed Integer Linear Programming)is proposed.Taking the annual operating conditions as an example,the interaction mechanism between the operating characteristics of the heating network and the heat storage characteristics of the heat load,the equipment capacity allocation and the system economy is explored.(4)A two-stage optimal scheduling strategy for regional multi-energy systems considering thermal inertia is proposed.In view of the uncertainties in the actual operation of the system,taking into account the forecasting accuracy of renewable energy and load,a two-stage optimal scheduling strategy is proposed.In the intra-day economic dispatch stage,based on MPC(Model Predictive Control)method,CNN-GRU short-term forecast method is used to forecast the renewable energy and load.In the intra-day real-time adjustment stage,the output of the equipment is adjusted in real time according to the real-time feedback correction strategy,so as to reduce the prediction error and improve the real-time tracking ability of the output optimization instruction to the output of renewable energy output and load.