In a method for voltage modulation using a plurality of modules (2) connected in series and connected to a load (3) , the modules having supply sources (Aj) and switching means (Mj ) to connect or disconnect the supply sources so as to either decrease or increase, respectively, a voltage applied to the load (3), by a value equal to the voltage (Ej) supplied by the supply source, the switching means (Mj) are controlled by a central unit (1) , according to processing of at least one modulating signal (m) . The method provides for a balanced operation of the modules (2) and a considerable increase of the duty cycle frequency (fc) , keeping the same heat losses on each module, so that a smaller and less expensive low-pass filter can be set on the load (3) .