Electrical supply circuit for the generation of separately controllable current pulses

Electrical supply circuit for the generation of separately controlled current pulses (K), particularly for resistance welding, comprising a transformer (Tr) which has on its primary side a storage capacitor (C) supplied with direct current and charged and discharged in a controlled manner, a load (R) being connected in the secondary circuit of said transformer, wherein

• two ancillary capacitors (C.sub.1, C.sub.2) of the same capacitance are connected between said storage capacitor and said transformer;
• each said ancillary capacitor is connected to the storage capacitor via a charge-control element (T.sub.1, T.sub.2) and to the primary side of the transformer via a discharge-control element (T.sub.3, T.sub.4) respectively, the transformer thus forming part of a discharge circuit for said ancillary capacitors;
• the capacitance of the storage capacitor is a multiple of the capacitance of the ancillary capacitors;
• each ancillary capacitor together with the inductance of said discharge circuit forms a parallel resonant circuit;
• and wherein control means (2) connected to said charge- and discharge-control elements are provided for alternately and cyclically charging and discharging said two ancillary capacitors in a controlled manner, thus generating dense sequences of partial pulses (k), each such sequence, transmitted via the transformer, forming one of the current pulses (K) to be generated;
• whereby said control means (2) are so designed that the cycle frequency (f.sub.k) of the partial pulses determined by the control means corresponds to the natural frequency of the aforesaid parallel resonant circuits.