Red Eléctrica de España is the Transmission System Operator (TSO) of Spain, which is responsible for transmission grid infrastructure, development, and power system operation. One of these assets is the 12.7 km underground section of a 400 kV overhead circuit near Madrid airport, where Red Eléctrica required an affordable cable monitoring solution to help prevent critical outages.

Elewit is the technology platform for Redeia (owner of Red Eléctrica), who are responsible for driving the energy transition and connectivity towards a sustainable future.

Our solution

Synaptec’s Greenlight solution allows synchronous and accurate instrumentation at multiple locations over long distances, without complex control power, or data networks being installed. Synaptec’s cable condition monitoring solution – since developed into Synaptec’s Greenlight solution – was selected by Red Eléctrica for deployment on the first major section of the circuit.

Three-phase Passive Secondary Converters for voltage (PSC-3-V) were retrofitted inside the substation from the overhead to underground line and connected to the existing substation voltage transformer to monitor voltage-based harmonic content changes. Single-phase Passive Secondary Converters for current (PSC-1-C) were installed along with split-core current transformers, over the phase cable at the substation and over sheath bonding cables at the joint bays. This enabled the system to monitor the phase and sheath currents in real time. Passive Temperature Transducers (PTT) were installed over cable joints to monitor their temperature.

At one cable end, all remote measurements of current, voltage, and temperature are acquired continuously and in real-time, and collated within the Synthesis® server. The Synthesis data service enabled secure recording of all data for offline analysis by Synaptec experts, and Red Eléctrica personnel are also able to use the data to validate and refine ATP models of the asset’s behaviour.