Diversified industrial manufacturer Eaton has launched an automated version of its proven and successful Xiria SF6-free Ring Main Unit (RMU). The new 12-24kV Medium Voltage (MV) switchgear is equipped with a Remote Terminal Unit (RTU) that allows utilities to easily acquire, process, store and transmit valuable data from the network. This information enables them to better manage their MV grid and increase operational uptime.
The change from a central to a more distributed generation of energy, increasingly originating from sustainable sources, which is fed into the network at various and variable points, requires an intelligent energy system. Especially at the MV level there is still a serious need to automate the switchgear so that utilities are able to obtain a detailed overview of the operational grid parameters. Automation can help eliminate the requirement for customers to report network failures and for service engineers to drive to the transformer substations in the field, it makes diagnosis more efficient and thus significantly improves the IEEE reliability standards System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI).
The RTU has been specifically developed for RMU applications; it can control and monitor up to five Xiria panels. Customers have the choice between two versions: the Semi-Automated Xiria (SA) offers remote control, protection and a number of communication features (IEC 60870-5-104, Modbus RTU), whereas the Fully-Automated Xiria (FA) also allows for measurement and control on the MV and the transformer side of the RMU (voltage, current, direction). By measuring current and voltage at the Low Voltage (LV) side and comparing these figures with the information from smart meters, inconsistencies are easily detected - indicating either a fault or an illegal power tap.
The RTU functionality generally includes alarming and event recording as well as data logging. Programming is simplified and completed in accordance with the IEC 61131-3 standard. Additionally, the units are equipped with an Ethernet port and wireless modem, providing monitoring and configuration through any web interface.
After an anomaly has been detected in the network, the automated Xiria RMU will contact the operating centre automatically. Here, appropriate alerts or warnings are displayed on aSCADA system that allow the operator to take suitable action to solve the issue or prevent further problems from occurring. In cases with directional fault indicators and additional logic, outages can often be solved within seconds of a fault occurring so that affect to consumers is minimal.
Eaton’s Xiria MV switchgear system is a reliable, economic and environmentally-friendly solution for RMUs and industrial switchgear. With Eaton’s vacuum and solid insulation technologies, the use of the environmentally harmful SF6 gas can be avoided. Xiria is one of the most compact systems of its kind on the market and is characterised by the high level of operational safety. The switchgear is suitable for applications up to 24 kV and used in compact transformer stations for power distribution, as well as in accessible stations in utility buildings and in industrial applications. The switchgear is available in two-, three-, four- and five-panel configurations. All panels are integrated in a single enclosed housing.