Development of Cylinder Deactivation Control during Idle for Conventional Engines

This report examines the advancement and utilization of cylinder deactivation technology that enhances fuel efficiency in conventional engines without hardware modifications. It operates by halting fuel supply to some of the cylinders in multi-cylinder engines and increasing the output power of the remaining active cylinders to maintain an idle state. By implementing this technology in the mass-produced 90° V-twin engine, the U502, and deactivating one of its two cylinders, fuel consumption during idling is reduced by over 30%. The focus of this study is on the technology developed to minimize engine speed fluctuations during the transition to cylinder deactivation and reactivation for the engine. By making various modifications to the fuel injection control sequence and optimizing the throttle opening of each cylinder in idle and driving conditions, engine speed fluctuations were minimized. This allows users to reduce fuel consumption while maintaining the engine’s original performance, with the transition in cylinder deactivation being virtually imperceptible.