Research On Energy Management Of AC / DC Hybrid Microgrid System

In order to improve the use efficiency of traditional energy,continuous development of distributed power generation technology can solve this problem and give full play to the role of renewable energy.This measure focuses on reducing the operation cost during the operation and power generation process of the microgrid and reasonably distributing the output of each distributed power source and the use of energy storage devices in the microgrid on the premise of reducing environmental pollution.In this context,a new microgrid structure,namely ac-DC hybrid microgrid system,is developed.The advantage of this system structure is that it can integrate the characteristics of pure AC and pure DC microgrid.In order to save cost and loss,it is necessary to effectively and reasonably optimize the energy distribution in the microgrid,so as to effectively maintain the good economic operation capacity of the microgrid system.In this paper,the optimal scheduling module of hybrid microgrid energy management is studied systematically.First of all,under the background of this topic,the current research status of microgrid and energy management operation is analyzed,and the basic structure of microgrid and the output power characteristics of each distributed power source are introduced.Secondly,an improved optimization algorithm is proposed.Based on the brief description of the defects of the traditional quantum particle swarm optimization(QPSO),such as falling into the local optimal solution too early,low accuracy and slow convergence rate,the initial chaotic mapping solution of the traditional QUANTUM particle swarm optimization(QPSO)is proposed,and the implementation steps and solving process of the improved algorithm are described in detail.The results show that the improved algorithm is superior to the traditional algorithm in convergence speed and optimization effect.Then,the optimal scheduling model of ac-DC hybrid microgrid in grid-connected operation mode is established.The optimization objective is to minimize the comprehensive operation cost,and the objective function and various constraints are given.Under the influence of day-ahead scheduling strategy,the solution is solved by combining the quantum particle swarm optimization algorithm with chaotic search mechanism.The effective output sequence is configured and the output of each distributed power source is calculated to calculate the hourly output power of each micro source throughout the day,so as to achieve the purpose of the lowest cost.Finally,using MATLAB program to set the simulation parameters,get the solved scheduling diagram and analyze it.Then,taking the microgrid data of a certain project as an example,the comprehensive operation cost results before and after the improved algorithm were calculated.The experimental results show that the improved QUANTum-particle swarm optimization algorithm has the advantages of faster convergence speed,higher accuracy and not falling into the local optimal solution too early.The comprehensive operation cost of the micro grid has also been saved to a great extent,which has certain theoretical guiding significance and engineering practical value for the overall economic operation of the micro grid.