Study On Energy Optimization Of AC/DC Hybrid Micro Grid And Analysis Of Its Uncertainties

From the late twentieth Century,with the development of micro grid distributed power,began to bring technical,economic and environmental benefits for the grid and users,while reducing the impact of micro grid connected to the grid.With more and more DC load,such as: electric vehicles,information equipment,light-emitting diodes and other access to the grid,AC and DC hybrid micro grid has become the future direction of the development of micro grid.Compared with the traditional AC microgrid optimization,AC / DC load and power flow problem should be considered in the optimization of AC / DC hybrid microgrid.In order to realize the optimal operation of AC / DC hybrid microgrid,the energy optimization problem of AC / DC hybrid microgrid is studied in this paper.Specific work as follows:Firstly,the composition,characteristics and operation mode of AC / DC hybrid microgrid are introduced in detail.Considering the uncertainty of distributed power supply,the operating characteristics of photovoltaic power generation,wind turbine and micro gas turbine are analyzed,and the mathematical model is given.The microgrid load model considering uncertainty is established.In this paper,the bidirectional converter is regarded as an important channel for the energy exchange between the AC and DC sub networks.Secondly,the energy optimization model of AC / DC hybrid microgrid is established.In this paper,the energy optimization problem of AC / DC hybrid microgrid is discussed in detail,and the optimization objective function and constraint conditions are studied in detail.The establishment of the economy of the micro grid energy optimization model considering a hybrid AC / DC micro grid based on the investment income in accordance with the maximum and minimum annual cost and load shedding at least three aspects of establishing the objective function and constraint conditions are given to the optimization of DC micro grid.The optimization model is solved by particle swarm optimization algorithm and the traditional optimization algorithm.Finally,considering the complex uncertainties,we establish an operation optimization model and evaluation index model of DC micro grid,Monte Carlo method is used to deal with the given model,the optimization results were compared with deterministic operation and scenarios.The simulation results show that the optimal operation model and evaluation model can improve the AC-DC hybrid microgrid operation robustness of uncertain factors of the composite,can provide reference for operation optimization of hybrid AC / DC microgrid.