Abstract: The invention relates to a voltage conversion method specially feasible for the transformation of low voltages to high voltages by means of a switching convertor. The method according to the present invention eliminates the current transients (B) through the switching unit (S), which is controlled in such a way that the time period (t.sub.F) during which the switching unit (S) is in its off-state is made to have a duration such that the resonance voltage (D.sub.u) on the transformer windings always has a predetermined phase, when said switching unit (S) is triggered to change to its conduction state. Voltage conversion according to the invention has high efficiency and causes little radio-frequency interference.