A DC power supply comprising: an AC generator having a number of output phases; and a converter system having a number of phase converters for converting an AC voltage to a DC voltage, the number of phase converters being the same as the number of output phases of the AC generator and each phase converter of the converter system being arranged to receive an AC voltage from a different one of the output phases of the AC generator, wherein each phase converter of the converter system comprises: a first H-bridge circuit comprising a first AC terminal for receiving an AC voltage from a first terminal of an output phase, a second AC terminal, a first DC terminal and a second DC terminal; a second H-bridge circuit comprising a first AC terminal for receiving an AC voltage and configured to be coupled to a second terminal of said output phase, a second AC terminal, a first DC terminal and a second DC terminal; an isolation block configured to provide for an isolated connection between the second AC terminal of the first H-bridge circuit and the second AC terminal of the second H-bridge circuit so that DC signals cannot pass between the second AC terminal of the first H-bridge circuit and the second AC terminal of the second H-bridge circuit but AC can pass; and a phase converter DC voltage output with a first terminal and a second terminal, wherein the first terminal of the phase converter DC voltage output is connected to the first DC terminal of the first H-bridge circuit and the first DC terminal of the second H-bridge circuit; and the second terminal of the phase converter DC voltage output is connected to the second DC terminal of the first H-bridge circuit and the second DC terminal of the second H-bridge circuit, wherein the converter system further comprises a converter system DC output with a first terminal and a second terminal, the first terminal of the converter system DC output being connected to the first terminal of the phase converter DC voltage output of each phase converter; and the second terminal of the converter system DC output being connected to the second terminal of the phase converter DC voltage output of each phase converter. wherein each phase converter of the converter system comprises: a first H-bridge circuit comprising a first AC terminal for receiving an AC voltage from a first terminal of an output phase, a second AC terminal, a first DC terminal and a second DC terminal; a second H-bridge circuit comprising a first AC terminal for receiving an AC voltage and configured to be coupled to a second terminal of said output phase, a second AC terminal, a first DC terminal and a second DC terminal; an isolation block configured to provide for an isolated connection between the second AC terminal of the first H-bridge circuit and the second AC terminal of the second H-bridge circuit so that DC signals cannot pass between the second AC terminal of the first H-bridge circuit and the second AC terminal of the second H-bridge circuit but AC can pass; and a phase converter DC voltage output with a first terminal and a second terminal, wherein the first terminal of the phase converter DC voltage output is connected to the first DC terminal of the first H-bridge circuit and the first DC terminal of the second H-bridge circuit; and the second terminal of the phase converter DC voltage output is connected to the second DC terminal of the first H-bridge circuit and the second DC terminal of the second H-bridge circuit, a first H-bridge circuit comprising a first AC terminal for receiving an AC voltage from a first terminal of an output phase, a second AC terminal, a first DC terminal and a second DC terminal; a second H-bridge circuit comprising a first AC terminal for receiving an AC voltage and configured to be coupled to a second terminal of said output phase, a second AC terminal, a first DC terminal and a second DC terminal; an isolation block configured to provide for an isolated connection between the second AC terminal of the first H-bridge circuit and the second AC terminal of the second H-bridge circuit so that DC signals cannot pass between the second AC terminal of the first H-bridge circuit and the second AC terminal of the second H-bridge circuit but AC can pass; and a phase converter DC voltage output with a first terminal and a second terminal, wherein the first terminal of the phase converter DC voltage output is connected to the first DC terminal of the first H-bridge circuit and the first DC terminal of the second H-bridge circuit; and the second terminal of the phase converter DC voltage output is connected to the second DC terminal of the first H-bridge circuit and the second DC terminal of the second H-bridge circuit, wherein the converter system further comprises a converter system DC output with a first terminal and a second terminal, the first terminal of the converter system DC output being connected to the first terminal of the phase converter DC voltage output of each phase converter; and the second terminal of the converter system DC output being connected to the second terminal of the phase converter DC voltage output of each phase converter.