Abstract: A method and a device for controlling a brush-commutator assembly of a machine under application of an electrical processing and control unit, by sensing one or more operating parameters of the electric machine, the sensing values being processed and converted into one or more control signals controlling the operation of the brush-commutator assembly to provide an optimal commutation process of the machine current. The machine current is sensed and the pressing exerted on the brushes is controlled by a fluid under pressure; the brush tracks, moreover, being engaged and disengaged upon increase and decrease of the machine current respectively in order to maintain an optimal current density in the brushes. One or more sensors for sensing operating parameters of the electric machine are used and a processing and control unit to process the signals sensed by the sensors and to supply control signals to one or more control means controlling the operation of the brush-commutator assembly.