Abstract
Under service conditions the car engine works in the range of low load. For such a load there are some methods for determination of the economical trajectory of the points of work, used as a control line of the automatic drive system. The functional properties of the car are influenced not only by the maximum speed and acceleration ability, but its reaction to a change in the acceleration pedal position as well. If the drive automation keeps the rotational speed of the engine on the economical control line, then for the limited changes in the acceleration pedal position the car reaction is unsatisfactory. Strongly non linear dependence of power on the acceleration pedal position is badly received by a driver. Improvement is possible if another, so-called dynamic control line is used. There is no, however, any accurate method of determination of the dynamic trajectory of the working points. The paper contains a method of explicit determination of such a trajectory. Since dynamic and economical trajectories are different, a change of the control line into the dynamic one increases the car sensitivity but causes the increased fuel consumption. In the paper it has been shown that the Integrated Control System of the Drive Train gives new possibilities. The economical control line can be applied for shaping the dynamic characteristic of the car.
Although only one control line (economical) is applied, it is possible to form the dynamic characteristic of the car. We can do it not by a change of a control line (like in conventional solutions) but as a result of programming the relation between the accelerator pedal position and the throttle inclination in the spark-ignition motor. Thus, we can obtain the car properties as for the change in the control line but without worse efficiency of the car drive.