An integrated unified common information model（UCIM） covering application levels ranging from the process level， the bay and substation levels to the control center level is developed based on the IEC TC 57 common information model（CIM） and IEC 61850 substation configuration description language（SCL）. The rules for the SCL model and CIM to UCIM mapping processing are studied， based on which the power system models and applications are constructed， laying a foundation for the unified and correlated modeling of the power system primary and secondary equipments. The UCIM can be adopted to integrate current power system applications and develop new location-transparent applications.