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Stadt takes next step with stealthy propulsion system

Warship Technology: March 2021WT Mar 21 RSS Propulsion


Stadt in Norway, which specialises in AC drives and integrated electric propulsion systems, has signed a contract with the Royal Norwegian Navy for a development project that will further enhance the company’s ‘STADT Stealth Lean Propulsion System.’


The stealthy propulsion system was developed to be as electromagnetically ‘quiet’ as possible, with no electromagnetic interference (EMI), acoustic switching noises and no harmonic voltage distortion. The concept eliminates the need for transformers in the propulsion system and electrical losses in the drives are minimised.


The innovative Lean Propulsion system also has a very high level of redundancy at all levels of the drive system and requires less space and weighs less than the alternatives, the Norwegian company claims. Other advantages include minimal need for cooling for the drives and systems, there is no need for screened power cables and cable segregation, and the system is based on rugged, proven technology. Stadt also claims that the lean propulsion concept has a lower mean time between failures than other propulsion concepts and an 80% reduction in the number of components required.


The Lean Drive concept was patented in 2008 and has since been applied on a number of naval vessels, including a number of naval, coast guard, offshore and commercial vessels.


In a statement, Stadt said increased use of electrically powered weapon systems and in the many benefits of electric propulsion has created significant interest in the Royal Norwegian Navy and other navies in the application of electric propulsion concepts on warships.


Stadt highlighted navies’ desire to reduce their carbon footprint, reduce power consumption and utilise new type of low-emission power sources. It also highlighted navies’ desire to increase operational range and enhance the stealth of surface combatants.


Among the most important drivers of interest in advanced electric propulsion technology is the development of new types of ‘pulse’ weapons for warships that requires a lot of electric power, whether AC or DC format, at different voltage levels.