Abstract: The invention relates to an electrical driving unit for a rolling motor vehicle of the kind comprising an electrically motorized subassembly which is fed by a direct current supply subassembly and controlled by an electrically regulated control subassembly and is connected to the running carriage of the vehicle via a gear box, clutch and secondary transmission. This driving unit is remarkable in that the abovementioned electrically motorized subassembly is a motor called "compound" with a series excitation winding and a parallel excitation winding; both connected between said electrically motorized control subassembly and the direct current supply subassembly, which is comprised of a series of accumulator batteries. Applications of the invention include electrical propulsion of land motor vehicles.