The parties have teamed up to further develop the Battery Short-Circuit Limiter (BSCL) protection device for large-scale battery solutions and advanced DC power distribution.

Connecting high-energy-content batteries to one electrical system carries a high risk of releasing a massive amount of short-term current that can result in system damage.

Consequently, battery packs must be split between several DC-Hubs to handle the amount of energy. The more batteries are hooked up, the more DC-Hubs are required - theoretically up to eight for a 20 MWh ESS.

The BSCL was invented to limit short-term current from each set of batteries, immediately blocking the short-circuit system.

The solution allows more batteries to be connected to the electrical system and fewer DC-Hubs, making the entire system more compact and viable (thanks to space-saving of cabinet length and better safety, efficiency and reliability).

"The BSCL is essentially an ultra-fast, semi-conductor-based protection device that operates based on actual system measurements with microsecond response. It opens the DC electrical circuit by disconnecting a battery set in the event of a fault anywhere in the system, preventing the battery set from discharging itself. Such a sudden release of energy could result in major damage and, in the worst case, an electrical fire. BSCL minimises the risk by stopping the energy loss in microseconds," Teemu Heikkilä, Head of Product Line, Converters at Yaskawa Environmental Energy / The Switch, explained.

He also highlighted, "From a technical perspective, the market hasn't yet come to grips with this connectivity challenge. Class rules, which were primarily designed for AC/DC systems, are lagging behind the rapid pace of technology in DC power distribution. The BSCL is the first product fit for purpose with battery systems that are getting bigger almost by the day. Its key benefit, mirroring the electrification trend where the larger the ESS the better, is that you can increase the energy content of the ESS while minimising the number of parallel systems required. In principle, implementing BSCL means you still only need two DC-Hubs for an ESS up to 40 MWh, so the savings grow in tandem with the size of the battery package."

The BSCL is a standalone product to be placed close to the batteries and between drives. The device engineered by Yaskawa Environmental Energy / The Switch is particularly suited to work with Corvus Energy's Blue Whale ESS, developed for large battery installations ranging from 10 MWh and upwards. It can also be retrofitted to existing systems for extra security.

The BSCL is closely related to Yaskawa Environmental Energy / The Switch's Electronic Bus Link (EBL) and Electronic DC Breaker (EDCB). The devices serve to guarantee selectivity and safety through ultra-rapid fault detection and disconnection, ensuring complete redundancy in DC power distribution for fully electric and hybrid vessels.

"We are pleased to join forces with Yaskawa Environmental Energy / The Switch. Their unique skill in thinking outside the box to solve complex challenges makes them a valuable partner on our journey to decarbonise shipping. Their innovative technology makes a big difference for the utilisation, scalability and safety of marine battery systems," Geir Bjørkeli, Corvus Energy's CEO, said.

Photo: Corvus Energy