Drives & Controls January 2024

TECHNOLOGY n THE INCREASED USE OF DC (direct current) in industry promises new ways to raise energy eciencies, and to simplify the integration of renewable energy and battery technologies. But, despite its potential attractions, DC is not widely used in industry today. One reason for this are signi‚cant hurdles in terms of error protection and fault isolation. If a short-circuit occurs, the rise time of the resulting large residual current is much shorter than in AC applications, posing a major challenge for conventional circuit-breakers. ABB has therefore developed a low-voltage DC circuit-breaker with the aim of facilitating novel DC systems of the future and paving the way to a sustainable energy transition. The Sace In‚nitus breaker is the ‚rst IEC 60947-2 certi‚ed, semiconductor-based breaker that uses power semiconductors with high current-carrying capacities and switching speeds in the microsecond range, to provide fast, safe interruption of fast-rising residual currents in DC applications. The all-in-one protection device provides fault protection and isolation, combined with connectivity and sensing technologies. All of the components – power electronics, mechanics, cooling, control, sensors and communications – are combined in a compact, easy-to-install device. ABB says that the breaker o‘ers the following attractions: n switch-o‘ times that are 100 times faster than conventional protection systems; n isolation of faulty zones to avoid complete system shutdowns; n almost no energy release in the event of electric arcs, reducing risks signi‚cantly; n high eciency thanks to a new semiconductor technology which is claimed to have the lowest forward losses in semiconductor-based circuit-breakers; and n service lives that are up to 100 times longer than for other systems. “Renewable energies, battery storage and smart grids are essential for the sustainability of future energy systems,”explains Dr Thorsten Strassel, global product manager for semiconductor circuit-breakers at ABB Electri‚cation. “The breakthrough technology of the Sace In‚nitus will play a prominent role in the transformation of low-voltage grids that are critical to the energy transition. For these DC networks, [it] provides comprehensive, ultra-fast protection. This removes a key hurdle for the use of DC grids in industry and other segments.” cation Solid-state circuit-breakers could open up novel DC applications The rst IEC 60947-2 certi ed semiconductor-based circuit-breaker will open up novel DC network applications