Abstract: A direct current regulator between a direct current power supply source and a load circuit includes a main thyristor and a quenching thyristor connected in parallel with the main thyristor through a series connection of a quenching condenser and inductive reactance. A change-over thyristor is connected into the circuit of the quenching thyristor, another thyristor is provided for recharging the condenser and a control unit is provided for gating the various thyristors to set their required ignition periods. The main thyristor connected in the lines leading from the voltage source to the load circuit is relieved of the charging as well as the change-over function by the use of additional thyristors, thus attaining a wider range of adjustment for the output voltage, and only one reactor component is required for the thyristor-controlled quenching and change-over circuits.