1.China Electric Power Research Institute(Nanjing)，Nanjing210003，China;2.NARI Group Corporation(State Grid Electric Power Research Institute)，Nanjing210003，China;3.NARI Technology Development Co.Ltd.，Nanjing210061，China

This paper provides a design method of database information model and its application program interface（API）using IEC61850common data class（CDC）which can be applied in station-layer devices.The database is characterized by the three-layer architecture that consists of the information model，the equipment model and the application model.The information model is created directly using the substation configuration description（SCD）model，while the equipment model is built with the IEC61970common information model（CIM）.Since the reuse of the standardized information model and equipment model is made，the integration supplier can focus on advanced application in substations.In compliance with IEC61850CDC definitions，the relational database structure and the object reference oriented retrieval API of the information model can be defined.With the universal information model，the procedure of project implementation can be significantly simplified.