The greatest difficulty on ships in recent years is to decrease the environmental impact of the exhaust from Diesel engines. For this, it is necessary to improve the combustor efficiency to suppress the fuel input rating, and to suppress the generation of various poisonous substances. One of the most effective method is to optimize the fuel injecting timing. Using a hydraulic servo valve, we can boost fuel pressure before injection, and starts injection at the best timing for effective combustion. Another method is to keep a high pressure in a fuel oil tank and control the starting and stopping of fuel injection with a solenoid valve, which is attached on the injection valve. The first system has proved too expensive because it uses the high price servo valve. The application of the latter system is thought to be limited to small engines, such as cars. This is because a high speed and large capacity electromagnetic valve are required. This research proposes a new composition for a simple, cheap and efficient fuel injection system with a Direct Drive Volume Control actuator. With this system we attempt to improve fuel costs and improve exhaust properties. This is achieved with optimizing injection pressure and injection timing to the operating condition.
