In the process level of digital transformation of substations, interface conversion devices are added between cross-bay device and bay device to meet the need for cross-bay device to continue operating while simultaneously connecting old device that has not been transformed and new device that has been transformed. An automated configuration scheme for the configured IED circuit description file (CCD) of the interface conversion device is proposed. For the digital transformation of conventional substations, digital modeling technology of the substation secondary circuit is adopted to achieve automatic mapping between conventional input and output and process GOOSE messages. The CCD file automation configuration scheme has changed the current situation of manual editing of CCD files of interface conversion devices, solved the problems of non-standard CCD file, error prone, and difficult on-site management, and improved the efficiency and quality of digital transformation of substations.