Terna transforms its maintenance strategy
Terna Rete Italia SpA has taken significant steps to prevent failures and focus on asset maintenance based on the real condition of a transformer’s insulation.
As a result, the failure rate of transformers has been well below 1% for several years now.
Terna has been using continuous on-line monitoring since the 1980s, first for the most relevant equipment on its extra-high-voltage and high-voltage (HV) transmission system, namely, power transformers. More recently, the transmission system operator developed a HV monitoring system, named SMOAT, to monitor through-fault currents continuously on the majority of its on-line HV equipment.
The system is now fully operational, monitoring grid substations, HV/MV transformers, circuit breakers, current transformers and voltage transformers. The SMOAT sensors acquire the relevant parameters. An intelligent electronic device processes the data received, through fiber-optic or copper wires, from sensors and transducers. All the relevant values then are transmitted, using proprietary fiber-optic cables, to other existing systems such as the operation support platform.
Since 2018, Terna has installed the SMOAT system in more than 25 grid substations, covering many transformers, auto-transformers, circuit breakers, voltage transformers, current transformers and surge arresters. Grid substations similarly are being equipped with the SMOAT system in accordance with a three-year development plan from 2019 to 2021.
Source: T&D World