Device for converting electrical energy from an alternating three-phase supply to a continuous output, comprising a first, a second and a third input phase: characterised in that - the first phase is connected to the input of a first boost-type circuit through a first diode connected in the forward direction, and to the input of a second boost-type circuit through a second diode connected in the forward direction; - the second phase is connected to the input of the first boost-type circuit via a third diode connected in the forward direction, and to the input of a third boost-type circuit through a fourth diode connected in the forward direction; - the third phase is connected to the input of the second boost-type circuit through a fifth diode connected in the forward direction, and to the input of the third boost-type circuit through a sixth diode connected in the forward direction; the outputs from said first, second and third boost-type circuits being connected to a terminal of a first output capacitor; and in that - the first phase is connected to the input of a fourth boost-type circuit through a seventh diode connected in the reverse direction, and to the input of a fifth boost-type circuit through an eighth diode connected in the reverse direction, - the second phase is connected to the input of a sixth boost-type circuit via a ninth diode connected in the reverse direction, and to the input of the fifth boost-type circuit through a tenth diode connected in the reverse direction, - the third phase is connected to the input of the sixth boost-type circuit through an eleventh diode connected in the reverse direction, and to the input of the fourth boost-type circuit through a twelfth diode connected in the reverse direction; the outputs from said fourth, fifth and sixth boost-type circuits being connected to a terminal of a second output condenser; and in that the other terminals of said first and second output capacitor are connected together. characterised in that - the first phase is connected to the input of a first boost-type circuit through a first diode connected in the forward direction, and to the input of a second boost-type circuit through a second diode connected in the forward direction; - the second phase is connected to the input of the first boost-type circuit via a third diode connected in the forward direction, and to the input of a third boost-type circuit through a fourth diode connected in the forward direction; - the third phase is connected to the input of the second boost-type circuit through a fifth diode connected in the forward direction, and to the input of the third boost-type circuit through a sixth diode connected in the forward direction; - the first phase is connected to the input of a first boost-type circuit through a first diode connected in the forward direction, and to the input of a second boost-type circuit through a second diode connected in the forward direction; - the second phase is connected to the input of the first boost-type circuit via a third diode connected in the forward direction, and to the input of a third boost-type circuit through a fourth diode connected in the forward direction; - the third phase is connected to the input of the second boost-type circuit through a fifth diode connected in the forward direction, and to the input of the third boost-type circuit through a sixth diode connected in the forward direction; the outputs from said first, second and third boost-type circuits being connected to a terminal of a first output capacitor; and in that - the first phase is connected to the input of a fourth boost-type circuit through a seventh diode connected in the reverse direction, and to the input of a fifth boost-type circuit through an eighth diode connected in the reverse direction, - the second phase is connected to the input of a sixth boost-type circuit via a ninth diode connected in the reverse direction, and to the input of the fifth boost-type circuit through a tenth diode connected in the reverse direction, - the third phase is connected to the input of the sixth boost-type circuit through an eleventh diode connected in the reverse direction, and to the input of the fourth boost-type circuit through a twelfth diode connected in the reverse direction; - the first phase is connected to the input of a fourth boost-type circuit through a seventh diode connected in the reverse direction, and to the input of a fifth boost-type circuit through an eighth diode connected in the reverse direction, - the second phase is connected to the input of a sixth boost-type circuit via a ninth diode connected in the reverse direction, and to the input of the fifth boost-type circuit through a tenth diode connected in the reverse direction, - the third phase is connected to the input of the sixth boost-type circuit through an eleventh diode connected in the reverse direction, and to the input of the fourth boost-type circuit through a twelfth diode connected in the reverse direction; the outputs from said fourth, fifth and sixth boost-type circuits being connected to a terminal of a second output condenser; and in that the other terminals of said first and second output capacitor are connected together.