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In recent years, improvement of in-use fuel economy is required with tightening of exhaust emission regulation. We assume that one of the most effective solutions is ACC (Adaptive Cruise Control), which can control a powertrain accurately more than a driver. We have been developing a fuel saving ADAS (Advanced Driver Assistance System) application named “Sailing-ACC”. Sailing-ACC system uses sailing stop technology which stops engine fuel injection, and disengages a clutch coupling a transmission when a vehicle does not need acceleration torque. This system has a potential to greatly improve fuel efficiency. In this paper, we present a predictive powertrain state switching algorithm using external information (route information, preceding vehicle information). This algorithm calculates appropriate switching timing between a sailing stop mode and an acceleration mode to generate a “pulse-and-glide” pattern.

In 1991, linear O2 sensors for lean-burn control were introduced in production vehicles for the first time in the world. Since then, the linear O2 sensors have been used mainly for the precise λ control. Recently requirements for Oxygen sensors have become increasingly stringent in the trends of tighter vehicle EM control requirements and lower fuel consumption. In response to these trends, NGK SPARK PLUG CO., LTD. has developed a new generation linear O2 sensor, which has a high water toughness and requires less power consumption.

In this study, the possibility of real-time HCCI control in a multi-cylinder gasoline engine was examined. Specifically, we applied a multivariate analysis based on an experimental design of quality engineering, and picked out several engine parameters which influence gasoline HCCI combustion stability. We clarified the characteristics of engine parameters in a gasoline HCCI operation area and propose the control concept: The internal EGR control is applied to multi-cylinder control by using the variable valve system, and air-fuel mixture control is applied to each-cylinder injection control while keeping the mixture homogeneous. Combustion conditions and engine out A/F need to be detected and fed back individually for each cylinder. With the proposed concept, it is possible to construct a real-time HCCI control system in a multi-cylinder gasoline engine.