Energy Management For Microgrid Under Uncertainty In Renewable Generation And Demand

A Microgrid is an active distribution system consist of distributed energy resources(DER),energy storage units(ESU)and controllable loads(CLs).It is connected to the main utility grid through the point of common coupling(POC).The main objective of this research study is to provide forecast and economic dispatch related solutions for grid connected and isolated microgrid in order to control and optimize the flow of energy from microgrid to the main utility grid.A practical test bed system is considered to carried out test consist of a PMSG type Wind turbine,Solar Panels,Vanadium redox flow battery,Lithium-Ion battery,Microturbine unit and Diesel generator with a power rating of 2.5MW,450kW,200kW,150kW,130kW,500kW respectively.A critical load of 2MW and a non-critical load of 500kW are considered in this study.A critical load is supposed to receive power in both modes of operations of microgrid while the non-critical load can be curtail based on the availability of energy.Robust Fuzzy prediction interval modeling is used for generation forecasting of the wind and solar resources.A dilute,distributed and intermitted nature of power sources create a huge challenge in front of scientists to overcome,the forecast of these sources even get harder with constraint in the isolated mode of microgrid operation,where a little error creates a large instability in demand and supply of energy.The overall problem is analyzed from the basics and modifications are made in existing algorithms to create more intelligent approach.The cost function is minimized based on hourly and minute based predictions.The minimum error is obtained based on real power values from the site via comparison through different benchmarks.In the second part of this paper,swarm optimization is used to address economic dispatch problem in grid connected microgrid.Matlab and Python languages are used to solve total cost function of microgrid including investment,fuel,and operation,mainte-nance,and replacement costs of different components of the microgrid.The main objec-tive of this part of the study is to minimize the transaction cost function while satisfying the load demand of the site under uncertain behavior of renewable generation and load.The minimum total cost function is compared to the various situation through scenario based analysis in order to check under different load and generation uncertainties.At last,the total cost function is minimized and integrated into forecasting module which then works together to provide the solution of economic dispatch problem.The proposed method is valid for grid connected and isolated microgrids.