The increase in DC grids onboard vessels and our answer in protecting them
In collaboration with KWx, Astrol Electronic AG developed a solid-state 1,5 kV DC breaker switch for marine applications. This unique technology provides maximum flexibility for onboard DC grids and protects against short-circuit currents in any part of the grid. We proudly announce the DNV-GL marine product type approval of the 0.5kA and 1.25kA DC breaker switches.
Hybrid and all-electric ships become increasingly popular. To be able to support larger electrical systems, capable of integrating alternative energy sources and storage systems. DC is the onboard power distribution system of choice. This, thanks to its ability to handle large power flows in a confined space with high system efficiency and low life cycle cost.
Vessels with an onboard DC grid have been proven to operate at the highest energy efficiency level while minimizing CO2, Nox and Sox emissions. This enables significant power savings and decreases operational cost.
As said DC links are extremely suitable, but safety is an issue. Proper protection against short-circuit currents and power overload is of essential importance. We proudly announce our DNV type approved solution to protecting the onboard DC grid: the Astrol 1,5kV solid state DC breaker switch.
DC breaker switches for marine applications
Based on many years of experience in the manufacturing of high-power solid-state switches for different applications and after consulting various capable engineers working in the Dutch maritime industry, Astrol Electronic developed a series of DC breaker switches for the marine industry. These ultra-fast DC breaker switches protect the onboard DC grids against short circuit currents in any part of the grid, enabling much more efficient topologies.
Maximize vessel and system up-time while minimizing maintenance costs
The DC breaker switch technology ensures maximum safety onboard, while reducing the total cost of ownership by preventing losses from system down-time, ship down-time, critical component failure and maintenance costs. The modular design enables easy integration within existing applications. Last but not least, this solution is future-proof since the largest models of the DC breaker series are capable of handling up to 5kA. Certification of the largest versions by DNV-GL is pending.
Enabling safe and redundant closed bus operations
Traditional marine energy systems are designed for open bus mode. This means that these systems operate completely separate. This specific design is less efficient but necessary for safety reasons. A closed bus system is a more complex and tightly integrated system and is demanding to build and to operate safely. The DC breaker switch enables these smarter solutions with equivalent safety, resulting in fuel savings, lower maintenance costs and a reduction of the environmental footprint. The fast switch-off times of the DNV-GL approved DC breaker switch contributes to an easier validation of the fault tolerance of the connected systems and selectivity zones, including live short-circuit testing of worst-case failure modes.
How did it all start?
In 2014 we gathered over 20 maritime-related companies, mainly ship builders and system integrators, to discuss their challenges in protection the onboard DC grid. What would be the ideal solution for fast fault interruption in cases of a short circuit situation or power overload? A lot of valuable information was captured and analyzed. This interactive session gave us a clear view on what the market needed. Next step was finding an electrotechnical engineering company who was able to engineer and create the product the market was waiting for. This brought us even closer to our appreciated Swiss supplier Astrol Electronic AG. A lot of engineering, designing and testing was done to create a full range of 1,5 kV DC breaker switches.
The development process of the DC breaker switch is a perfect example of how the triangle customer, KWx and supplier/partner co-created a product that was the missing link in protecting onboard DC grids. One that we are very proud of!