Study on air-fuel ratio control of coal-bed gas engine based on fuzzy PID control

By analyzing air-fuel ratio control characteristics of pre-mixing coal-bed gas engine, an air-fuel ratio control scheme used in pre-mixing coal-bed gas engine is proposed. The air-fuel ratio fuzzy PID controller is built, which used in transient working condition and steady working condition of coal-bed gas engine. The simulation on the process of air-fuel ratio control is researched. This control scheme is showed to have ideal control effect, preferable stability and robustness based on the air-fuel ratio fuzzy PID controller simulation result. The problem of air-fuel ratio disturbance is well solved, when the engine´s working condition changes.