Six months after the IEC 61850 communication standard for sub-station automation was released, Siemens Power Transmission and Distribution (PTD) installed one of the world's first substations with complete (or 100%) IEC 61850-based control. The equipment was installed in November 2004 in a 16-kV substation in Switzerland owned by Aare-Tessin AG (Atel; Olten, Switzerland), an independent energy group operating throughout Europe. Siemens installed its SICAM PAS (Power Automation System) control system in accordance with the new standard throughout the substation. The new communication standard ensures the required interoperability in the substation. All connected protection devices now “speak” a common language, regardless of manufacturer, which smoothes the exchange of data with one another.

There have been relatively few cases where substation protection systems and bay controllers from different manufacturers could communicate with each other because a variety of communication protocols exist in substations across the world today. For the operator, this means a lot of work during commissioning and unnecessarily high costs, as countless protocol converters have to be used. A further problem is that different communication protocols have a negative effect on the long-term maintainability and extendability of the equipment. IEC 61850 will be a great help in this respect.

Siemens PTD was engaged to exploit the benefits of the new standard. In addition to making the substation fit for the future by ensuring its communication capability in line with IEC 61850, Siemens also replaced the more than 40-year-old switchgear at the substation with its new metal-clad, compartmentalized medium-voltage switchgear system, NX Plus C. A further requirement was the ability to remotely control and monitor the equipment. The protection and control functions were to be realized using combined protection/bay control devices. State-of-the-art substation control and protection was to be the heart of the substation.

Because Siemens PTD had played a major role in the development of the new standard, it was able to implement the necessary communication technology in its substation control and protection at a very early stage. In SICAM PAS, the substation now has an open control system using IEC 61850 as the standard for communication between the bay and substation levels.