General purpose 100% solid state Direct Current drive for rotary DC machines with four quadrants operation. It is to say that allows the rotary DC machine to act like motor or generator in the two direction of possible rotation. In the first and third quadrant as motor in both direction of possible rotation, and in the second and fourth quadrant like regenerative brake DC generator, recovering the energy towards the DC network supply.To obtain that generalized control for DC machines of any type, the invention subject of this patent, is based on the interaction of two original ideas that they are: (1) Maintaining the direction of the current in one and only one of the two main windings of the DC machine (7) either field or armature, by means of a rectifier bridge (6). (2) Use a DC controlled power supply (14), with reversible polarity to feed the complete machine.