Double Level Optimal Dispatching Strategy Of Microgrid Considering Flexible Resources

The output of renewable energy in microgrids and the supply of demand side loads have strong random fluctuations,which may have adverse effects on the stable operation of microgrid systems.Especially in extreme disasters,chain failures are more likely to occur.Therefore,it is very important to develop effective scheduling strategies.This not only reduces the operating costs of the system,but also ensures the stability and safety of the microgrid.On the other hand,the complex structure of various flexible resources,difficulty in accurately establishing corresponding models,and the tendency to fall into local optima when scheduling them using traditional optimization algorithms are also urgent issues in the current research field of microgrids.Therefore,on the basis of considering flexible resources,this paper proposes a two-level optimization scheduling method using an improved MOEA/D algorithm,aiming to ensure the economic and stable operation of microgrid systems.The main research work of this article is as follows:First of all,introduce the research background,significance,and current research status of flexible resources in this topic,as well as the research results of multiobjective optimization scheduling in microgrid systems.Next,the characteristics of various flexible resources and the shortcomings of current optimization and scheduling methods for microgrid systems are elaborated.Simultaneously analyzing the scheduling advantages of microgrid systems with flexible resources,providing a basis for establishing a two-level optimization scheduling method for microgrids with flexible resources in the following text.Subsequently,due to the complex structure of various flexible resources,varying characteristics when connected to microgrid systems,and difficulty in accurately establishing models,this article introduces the basic structure and operation mode of microgrids containing flexible resources,and establishes mathematical models for each distributed unit in the microgrid containing flexible resources.We have constructed the basic structure of the load layer and source reservoir layer,as well as mathematical models of the objective functions and constraints of each layer,and proposed a twolevel optimization scheduling method for microgrids with flexible resources.In addition,the basic principles,specific processes,and improvements to the original algorithm were explained in detail.Then,in order to develop an optimized scheduling plan for microgrids that is more in line with daily life,this article classifies the dataset according to three typical scenarios: summer,winter,and transition season,and inputs the data into the model for validation.Through continuous iteration of the improved MOEA/D algorithm,the optimal scheduling scheme was ultimately obtained.This article compares the experimental simulation results with other schemes and finds that the average annual user cost has decreased by 6.85%,the average annual total cost of operators has decreased by 14.68%,and the average annual load loss rate has decreased by 6.65%.Verified the effectiveness of the two-level optimization scheduling method for microgrids that takes into account flexibility resources.Finally,to verify the impact of flexible resources on the performance improvement of microgrid systems under extreme disasters,this article analyzes the impact of extreme disasters on power systems,considers the impact of cascading faults on microgrid systems,and establishes corresponding fault models.Taking extreme disaster simulation results as input data for simulation experiments,combined with the distribution of renewable energy and load units within the microgrid system,and utilizing the advantages of flexible resources,an optimized scheduling strategy was developed that includes controllable power generation units and translatable loads.The experimental results indicate that adding flexible resources can effectively improve the performance of microgrid systems in the event of extreme natural disasters,ensuring the safe operation of microgrids.