Revisiting the adjustable mode of a locomotive startup to ensure the best use of the clutch

It is known that a locomotive startup process usually consists of two consecutive phases (initial and final). From the point of view of the adhesive force implementation, it is important how the driving force changes during each of the startup phases and what the length of each phase is. The law of distribution of the realized values of the adhesion coefficient and the use of adhesive force depend on the law of change in the startup driving force we use to approach the limit of adhesion. The choice of the startup mode can be crucial in the most heavy-duty mode of the locomotive - when starting-up and setting the train in operation. As a result of the conducted research, it was established that immediately after the motion onset, acceleration should not exceed 0.5% of the maximum possible for these conditions. It means that in the first sampling interval (up to approximately 5% of the starting duration), the driving effort must be sufficiently small, namely, F = 0,005·Fmax. Then, it must slowly increase to about 15-20% of the starting duration over each sampling interval. It is established that in the startup mode with the proposed step-by-step method of controlling the driving force, the speed of the locomotive almost completely coincides with its corresponding speed during continuous adjustment. Deviation makes up not more than 2-3%. It can be explained by the inertia of the wheelset drive of the locomotive, which will not lead to clutch stalling and wheel slipping.