Research On Multi-source Optimal Configuration And Economic Dispatch Of Active Distribution Network

Along with the development of wind power generation and photovoltaic power generation technologies,a lot of variable distributed generations(DG)integrated into the distribution networks.In order to accommodate these variable DGs,on the ont hand,it is recommended to promote the grid-interface performance by the use of energy storage(ES),micro-grid(MG)technologies,etc;on the other hand,the distribution networks need to reinforce the grid structure,and accomplish the active control and management to the DG,ES and controllable load,etc,by using the advanced communication technology,control technology and decision support system,etc.In this thesis,it is focused on the optimal configuration of flexible resources and economic dispatch of active distribution networks(ADN).The research process begin from the quantitative analysis of the probabilistic characteristics of variable DG,then the concept of power system flexibility is introduced,the flexibility requirement is considered throughout the entire research process.Based on the research route,the main research achievements are presented as follows:1.For the quantitative analysis of the probability and time-sequence charactieriscs of variable DG,such as wind power generation and photovoltaic power generation,a complete analysis flow and framework are provided,which include single-point characteristic,multi-points correlation,multi-points joint characteristics.2.For the problem of scenario simulation and selection during the probabilistic production simulation process,the frequently-used scenario simulation methods,such as Statistical sampling method,time series method,etc are summarized,and a scenarios reduction method is provided,based on the cluster analysis theory.3.The concept of power system flexibility is introduced,and its definition and connotation are clarified.For the quantitative evaluation of renewable energy accommodation ability and power system fleixibility based on the probabilistic production simulation,the related indexes are defined,such as:insufficiency of accommodation space probability;expected electricity surplus of renewable generation;insufficiency of flexible capacity probability;expected value of flexible electricity vacancy,etc.4.For the production simulation of variable renewable generation,such as:wind power generation,photovoltaic power generation,etc,a time-sequence probabilistic production method is proposed,which is based on the load time-series curve,and then the related evalution indexes,concerning the balance between power and flexibility supply and demand,are calculated step by step in time sequence.5.The influencing factors of renewable energy accommodation ability are analized and summarized.For the maximum utilization of renewable energy,a optimization model for the configuration of flexible resources is established,which consider several types of flexible resources,such as fuel-type DG} battery-type ES and charging pile-type controllable load,with the objective function of cost minimization of construction,operation and management.6.The technical and economical flexibility factors of AND were analized.Based on the flexibility requirement during the operation of ADN,an operational fleixibility index of ADN is proposed,and then an ecomomic dispatch model is established,in which the operational flexibility constrain is considered and the objective is maximum operational benefit.The flexibility requirements were fulfilled finanlly through the coordination and interaction between multi flexible resouces.