Research On Muti-day Receding-Horizon Energy Optimal Scheduling Method Of Microgrid System

Microgrid can integrate the advantages of distributed generation,coordinate the contradiction between distributed power supply and the power grid,and make full use of various distributed energy sources.Combining with local load,energy storage system and the two units such as related monitoring and protection,it constitute a new type of power system with self-protection,control and management capabilities.The economic dispatch of microgrid is an important research topic.Its purpose is to realize the optimization of the comprehensive cost while satisfying the load demand,which is the key to the economic benefits of microgrid.Most of the literatures of micro grid economic dispatch study aims at the single day scheduling problem,and the energy storage capacity at the end of the scheduling day is usually directly set at half of the energy storage capacity.In practical operation,the output of the micro sources may vary greatly under different scheduling days.Although a single day scheduling model can meet operating requirements for each scheduling day,but if a better economy is to be achieved,the microgrid needs to formulate a multi-day continuous scheduling schemeAs one of the most important devices in microgrid,the charging and discharging strategy method of energy storage and dispatching microgrid are closely related to the economy of microgrid operation.Aiming at the multi-day continuous scheduling problem of microgrid,a multi-day receding-horizon economic dispatch of microgrid system with energy storage contained based on two-stage optimization model was proposed.The method consists of two stages:The task of the first stage is to optimize the energy storage level at the end of the current scheduling day.The task of the second stage is to formulate the microgrid optimal operation scheme of the current day according to the level of energy storage optimized at in the first stage.The proposed method can be applied to the multi-day continuous scheduling problem of microgrid,on the one hand,the scheduling problem is decoupled from time into a single day scheduling problem by setting the appropriate energy storage capacity at the end of the day,which makes the practical application of the model is convenient,on the other hand can take the comprehensive economy in multi day range into consideration by setting energy storage at the end of a single day scheduling model,in this way the benefits of energy storage can be obtained from a larger time scale to the greatest extent.Finally,a numerical example is given to illustrate the effectiveness of the proposed method.