With the smart grid construction boosting further, the requirements of model and information sharing between control center and substation increase, while the current commonly used communication protocol between control center and substation has been unable to meet the demand of communication. This paper proposes a real-time service communication protocol based on IEC61850. On the basis of specific communication service mapping openness, the abstract communication service interface (ACSI) is directly mapped to the TCP/IP communication protocol stack to build up a communication protocol in smart grid construction needs and meet the intelligent seamless communication requirements between control center and substation. The model conversion method and calibration method are also proposed.