Fuel Efficiency and Response of Load Control Methods for Premixed Charge Engines

The term engine readiness is proposed as an additional concept which should be considered when evaluating among various options for controlling power in homogeneous charge, SI engines. Although improving part load fuel economy is a desirable goal, engine readiness should not be sacrificed in the process. A variety of methods for power control are identified. In general, those which provide superior part load fuel economy suffer from poor response to driver demand, i.e., readiness, and vice versa. Other concerns of load control techniques: range, step size, cost, noise, emissions, safety, complexity, etc., are also considered.