Design And Study For Embedded MMS Protocol Package

Manufacturing Message Specification is an international standard that established by ISO and IEC which is used to exchange data and monitor message among industrial equipments under the network environment.IEC61850 substation communication network and system exchange data messages among substation equipments with the specification.The development and application of substation intelligent components were responsible by project group.IEC61850 standard should be used to exchange data messages with other intelligent electric device.In order to implement the communication software module of IEC61850,MMS protocol packets should be designed and implemented.Intelligent component is process layer of intelligent substation.For fight against the interference of harsh environment,intelligent components were composed of low-end embedded processors.The memory space of processor is minimal,but complete MMS program takes up too much space so that the system cannot runs very well.A standard MMS include many functions.Just a few of functions were used when IEC61850 is mapped on MMS,and not all of IEC61850 functions employ in intelligent component.Cut off the functions which were not used and implement MMS protocol package that required by intelligent components were major tasks of project on the basis of mapping relationships between IEC61850 and MMS.Moreover,dynamic linked data list is not supported by protocol package according to the characteristic of processor and real-time embedded Operating System,stationary node number of static linked list is used to implement relevant function.Innovation points of the research as follows:(1)Basis on the map relationships between IEC61850 object that server?logical device?logical node?data and data attribute and MMS object that virtual manufacturing device?domain and named variables and the correspondence relation between abstract communication service interface of IEC61850 service and MMS service to confirm MMS protocol package functions and content which must be reserved and implemented and which should be cut off.(2)The detailed analysis was accomplished to service structions and encoding method and decoding method of MMS protocol package,the task of encoding and decoding were completed.(3)Thetransition from dynamic linked list struction to static linked list was designed.After the required functions of system were designed,firstly,the connection between server and client was linked.And configuration parameters were configured by configuration tool.Then,the functions were test by testing software of client.Test results indicate that MMS protocol package which was designed and implemented achieved the required of system.