Individual A/F Control with Fuel-Gas Ratio Estimation for Multi-cylinder IC Engines

In IC engine with multi-cylinder, balancing the air-fuel ratio for individual cylinder is an important issue for providing high quality torque generation and reducing emission. This paper addresses the individual air-fuel ratio control problem for a six-cylinder engine with single sensor. First, a modeling to estimate the individual fuel-gas ratio, which provides the air-fuel ratio immediately, is proposed, and with the estimation model, an adaptive control approach to balancing the individual cylinder characteristics is presented. Under a given operating condition, parameter identification results for the estimation model are obtained by experiment conducted on a real engine test bench. Finally, experimental result with the proposed controller is demonstrated.