From process terminals to control center: fully automated Substation Automation System (SAS) testing

The commissioning, engineering, and maintenance of Substation Automation Systems (SAS) with Protection, Automation, and Control (PAC) functions involve significant testing efforts, accounting for much of the implementation time and cost. As SAS systems grow more complex, testing communication and signal functionality for Supervisory Control and Data Acquisition (SCADA) systems has become increasingly challenging. Initial wiring checks have shifted from traditional manual methods to digital verification of Substation Configuration Language (SCL) files against network messages. Automated testing explained in this paper offers solutions to these challenges, enabling the creation of reusable test cases for uniform bays. This method aligns with IEC 61850 standards, promoting interoperability and standardized engineering across substations. Advanced tools like intelligent I/O boxes simplify testing by replacing mechanical switches, supporting automated simulations of process signals, and integrating with virtual platforms for remote and unattended testing. The paper also outlines closed-loop testing, including assessments of IED communication (GOOSE, MMS) and SCADA Gateway protocols (IEC 60870-5-104).