Idling slide protective control method of locomotive

The invention relates to an idling slide protective control method of a locomotive. The method comprises the following steps of: detecting the acceleration d omega/dt of a locomotive wheel pair in real time, when the acceleration exceeds a protective threshold, i.e. domega/dt is more than ag, starting to unload a moment, and continuously searching the peak value of the acceleration, i.e. when d omega/dt =0 in the unloading process, searching the peak value; and instantly stopping to unload the moment when the peak value is searched, wherein the change rate of a motor torque dT/dt is 0, the adhesion of a locomotive wheel track recovers again and the change rate of the adhesive force of the locomotive wheel track dF/dt is more than 0. The invention can overcome the over-deepness unloading problem very well in the prior art, the problem cause the locomotive tractive effort loss to be great, affects the adhesion utilization of the locomotive and causes the front and back impacts of the locomotive.