A method of operating a hydrogen-fueled internal combustion engine. The engine is determined to have a mode control value, which represents a threshold torque. During operation of the engine, a demanded torque of the internal combustion engine is determined and compared to the threshold torque. If the demanded torque is less than the threshold torque, the engine is operated in a low load mode that uses spark ignition and pre-mixed combustion. If the demanded torque is greater than the threshold torque, the engine is operated in a high load mode that uses compression ignition and diffusion combustion.
Terrance Francis Alger; Thomas E. Briggs, Jr.; Graham Thomas Conway