On the development of a control system for a small bio-methane gas engine generator

In order to use the stable biomass resources that exist in rural areas, we have developed a small bio-methane gas engine generator that can be applied to various methane gas compositions. Different from other conventional researches, we added auxiliary devices such as the surge tank, extra carburetor and ECU to our conventional gas engine generator, instead of alternating the basic structure of the engine and the control method. Referred to the observation data such as the temperature, load and air-fuel ratio, we evaluated adaptability of auxiliary devices for various concentration of CH4. The surge tank and extra carburetor are useful for getting more air fuel and improve fuel-air mixture. Along with various concentration of CH4, the ECU could calculate the deviation of desired revolution and current revolution to adjust valve angle by a PID controller, and realize the generator running stable.