Drivability Control to Optimize the Operating Freedom in the Hybrid Vehicle Propelling System

A method of drivability control is newly developed for hybrid vehicles. "Drivability control" related with driver´s subjective feelings is considered for hybrid vehicles. One of the significant advantages of this method is to make the most of operating freedom in a propelling system without disturbing drive control. The purpose of this paper is to discuss the significance of the operating freedom, and then to describe the basic concept of the control method and its applications. The drivability control is performed by racking to satisfy a drive control criterion, which is given as a function of the accelerator pedal position, the vehicle velocity and its acceleration. The criterion, which does not include any characteristics of a power source, facilitates the effective utilization of the operating freedom.