Research On Communication Network For Realizing Coordinated Control Of Microgrid

In recent years,with the worldwide energy crisis,the drawbacks of traditional large-scale power grids are becoming increasingly prominent.The microgrid system of parallel multi distributed generations has become one of the hot topics in the field of renewable energy generation technology.Microgrid is an important part of smart grid.It can effectively support the stable power supply of large power grid,also flexibly guarantee the power supply requirements of regional load.The coordinated control between the distributed generations sources in the microgrid is the key to the stable operation of the microgrid system.And the coordinated control of the microgrid depends on the secure and reliable communication network,which makes the communication network of the microgrid particularly important.In order to ensure the safe and reliable operation of the microgrid,the coordinated control between the various distributed generations is needed,but the different control structures have different characteristics.This paper studies three kinds of control methods,namely,constant power control(PQ control),constant voltage and constant frequency control(U/f control)and droop control(Droop control)for distributed power generations interface inverter in microgrid.The overall control methods of three kinds of microgrids,including peer-to-peer control,master-slave control and hierarchical control,are compared and analyzed.According to the communication protocol of IEC61850 and the requirement of communication control in microgrid,three layers of microgrid communication network structure are designed.The important services real-time performance in the communication network and in after joining the wireless nodes are deep studied.The reliability of the communication network is analyzed.Finally,the OPNET network simulation software is used for modeling and simulation,and the simulation results show that the communication network meets the requirements of the fast and reliability of the coordinated control of microgrid.In order to meet the security requirements of the coordinated control of the microgrid,this paper studies the potential information security problems in the microgrid.And in combination with the information security level protection,the microgrid communication network is graded and analyzed.In accordance with the requirements of the information security level protection,the microgrid is protected in information security.The application of encryption technology in microgrid is verified by experiments.The results show that encryption technology can be applied to information security protection in microgrid.It also can ensure the security of communication network and reduce the risk of information security in microgrid.Thus the coordinated control of the microgrid is realized.