Method and arrangement for controlling the drive force and/or braking force of the drive motors of a tractive unit, providing total adhesion, at the friction engagement threshold of the wheels

摘要

For a method for controlling the drive force and/or braking force of the drive motors of a tractive unit, providing total adhesion, at the friction engagement threshold of the wheels in which an integrator is used as pseudo running axle, in each case the difference DELTA n between the starting variable of the integrator and the rpm of an associated drive axle serves as a measure of the wheel slip and the first time derivative of the engine speed difference d DELTA n/dt is formed by means of in each case a differentiating device, it is intended to overcome the wheel slip even under the most unfavourable frictional engagement conditions, e.g. even if, when the maximum frictional engagement is reached, the said frictional engagement no longer has a declining tendency whilst the slip increases. This object is achieved in that as soon as the difference in rpm is DELTA n NOTEQUAL 0 or exceeds a low threshold value, an excitation pulse generator (60) is switched on which periodically supplies pulses i to the vehicle control such that in each case for the duration of each pulse the tensile force or braking force of one or more drive motors (2) is raised by a small amount. In this process, the pulses i of the excitation pulse generator (60) are expediently suppressed during the time in which the differentiating device (22) outputs signals.