Economic Dispatch Of Multi-microgrid Systems With Multi-objective Evolutionary Optimization

To cope with global environmental problems and energy crises,Microgrid with distributed renewable energy power such as wind and solar energy has been widely developed due to its environmental protection,high efficiency and flexibility.With the development of Microgrid,Cooperation of multiple Microgrids in a certain area has been becoming more and more attractive since it can effectively decrease the pressure of Microgrid grid connection,significantly improve reliability and reduce the operation costs.The power operation and management of the Multi-microgrid system are the key points for keeping this system work in a safe,economical mode with high utilization of renewable energy.Motivated by this,we here focus on the study of economical dispatch of Multi-microgrid system with multi-objective evolutionary algorithms.The main research contents of this paper are as follows:(1)Modeling and evolutionary optimization of multi-objective economic dispatch for Multi-microgrid system.The power generation cost of single Microgrid is first selected as the optimal objective and modeled.Based on such models,the multiobjective power generation cost model of the Multi-microgrid system with power transactions is then constructed.The distributed powers together with the electricity translation prices are set as decision variables,and NSGA-II is used to perform the optimization under strong constraints.The proposed algorithm is validated by applying it to a Multi-microgrid system with three Microgrids,and provide the dispatch strategy in 24 hours when the decision purpose is to minimize the total power generation cost of the system.(2)Many-objective economic dispatch of Multi-microgrid system with CHP(Cool-Heat-Power): Based on the above-mentioned Multi-microgrid dispatch,Multimicrogrid with cogeneration of cold and heat is here considered to further optimize the energy structure and improve the energy usage efficiency.According to the mode of " fixing power by heat " to convert the cold and heat load into power load,and the corresponding models of the conversion are given.The objectives of minimizing the operation cost and emission pollution of single Microgrid are established and the manyobjective models of the Multi-microgrid economic dispatch are then presented.NSGAIII,a powerful algorithm for optimizing many objectives is then applied to the model under constraints.The proposed algorithm is validated in the three Microgrids system with CHP loads.The proposed multi-objective dispatch of Multi-microgrid system first considers the case that internal power transactions exist among the Microgrids,and presents NSGA-II based optimization for minimizing the power generation costs.Furthermore,Multi-microgrid system with CHP loads is concerned and NSGA-III is applied to optimize the many-objective models including minimizing the operation cost and pollution emission.Experimental results demonstrate that the algorithms of this paper can reduce the operation cost and pollution emission,improve the renewable power penetration,and optimize the energy usage structure.