Research On Optimal Scheduling Of Electric-thermal Coupling System Considering Uncertainty

In the process of global economic development,energy demand is also increasing,and the world is facing increasingly serious energy shortage and environmental problems.In light of China’s "3060" dual-carbon target proposal and the accelerated pace of construction of new power system,renewable energy has become the primary trend of China’s future power generation.As a crucial component of clean energy,the instability of wind power brings a huge challenge to China’s new power system.Furthermore,with the concept of energy internet and the development of cogeneration technology,the coupling relationship between power system and thermal system becomes more closely.In such a context,a reasonable optimization method for the power-thermal coupled system is urgently needed to realize the optimal and economic dispatch of the system.In this paper,the following work is mainly accomplished in this context:Firstly,this paper summarizes the treatment of wind power uncertainty problems and the current status of research on optimization problems of electric-thermal coupled systems,establishes a model of key devices in electric-thermal coupled systems,and constructs a model of power system network currents and a model of temperature mixing,transmission delays and thermal losses in thermal network systems,builds a basic framework of electric-thermal coupled systems,and provides theoretical and methodological support for optimal scheduling of the model.Secondly,this paper describes the general theoretical approach to wind power uncertainty problem processing and compares the advantages and disadvantages of various optimization methods.Finally,the distribution robust optimization model based on Wasserstein distance is selected to deal with the wind power uncertainty problem proposed in this paper.Based on the empirical distribution of wind power day-ahead prediction errors,the fuzzy set and support set of wind power day-ahead prediction errors are constructed,and the method is further combined with the constructed framework of coupled electric-thermal system to establish an optimal scheduling model,which is transformed into a solvable mixed integer linear programming form by strong dyadic theory.Finally,a large-scale power-thermal coupled simulation system with IEEE-39 node power system and 12 node thermal system is constructed in this paper for optimization simulation calculations.The results show that the distributed robust optimization method adopted in this paper can effectively reduce the system cost and lower the system wind abandonment.In addition,this paper explores the effects of energy storage and demand response mechanisms and thermal system modifications on the dispatch results by constructing different scenarios.The results show that both energy storage devices and demand response technologies can play a role in reducing costs and smoothing wind power system fluctuations in the electricity-thermal coupled system,and the effect of demand response is more obvious,and the effect of electric load demand response is better than that of thermal load demand response in demand response;CHP units with flexibility modification and thermal systems with pipe network insulation modification can effectively reduce the cost of system optimization scheduling.The effect of flexibility modification of CHP units is more obvious.