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Natural gas offers some advantages compared to diesel fuel: reducing operational costs and at the same time respecting tight emission regulations without complex exhaust gas aftertreatment. While high-speed lean burn gas engines are already widely used for stationary applications, there is a strong motivation to develop high-bmep gas engines for demanding applications such as marine propulsion application, off-highway traction, compressor drive, etc. In order to satisfy the specific application characteristics such as variable speed, highly dynamic operation and to mitigate specific gas engine challenges such as knocking combustion, new engine control concepts need to be developed. ABB's VCM (Valve Control Management) is an example of a compact and easy to integrate variable valve train system which allows optimization of the cylinder filling across the entire load and speed range. This way the engine knock margin can be managed through variation of the Miller cycle and the transient engine performance can be improved. Conventional load control devices in pre-mix stationary gas engines such as throttle and bypass valves have the inherent drawback of wasting a large part of the available turbocharging efficiency. VCM allows replacement of these control devices and hence improves both the gas exchange and high-pressure processes. Furthermore, VCM allows significantly shorter valve closing ramps which reduces valve throttling losses with extreme Miller timing. A simulation study demonstrates the potentials of a high-speed lean burn gas engine with variable valve timing and high-pressure turbocharging for a marine propulsion application. The steady-state simulations which are backed up by engine testing show that VCM enables: variable speed operation with high bmep, a wide engine operation map offering large torque reserves for FPP applications, lowered fuel consumption through optimized gas exchange and high-pressure processes. The transient performance was investigated along the FPP load characteristic. A simplified control system manages the gas injection and optimizes the Miller timing for rapid acceleration while respecting critical boundaries such as knocking combustion. The results show a very responsive transient performance comparable to sequentially turbocharged diesel engines. To sum up, the investigation showed at the example of a marine propulsion application that VCM in combination with high-pressure turbocharging enables high-bmep gas engines for demanding applications which were traditionally served by diesel engines.