CIRCUIT ASSEMBLY AND METHOD FOR PROVIDING ELECTRIC POWER FOR LARGE DC LOADS

The invention relates to a circuit assembly for providing electric power for at least one DC load, in particular for at least one electrolyzer cell, from at least one alternating current source, having a primary DC intermediate voltage circuit which is connected to a secondary DC intermediate voltage circuit via DC/DC converters, said secondary DC intermediate voltage circuit supplying the at least one DC load with electric power. The aim of the invention is to provide a circuit assembly for providing electric power for at least one DC load, in particular for at least one electrolyzer cell, said circuit assembly not only allowing a complete range of electrolyzer cells to be supplied with a direct voltage but at the same time also allowing an effective protection concept to be provided in the event of malfunctions in the DC load, the DC/DC converters, or the corresponding secondary DC intermediate voltage circuit. This is achieved in that the primary DC intermediate voltage circuit (4) is supplied with electric power from the alternating current source (3) via two inverters (7, 8) connected in series so that a central tap (9) is provided and in that means (12) for limiting the DC output voltage of the corresponding inverter are provided between the central tap (9) of the primary DC intermediate voltage circuit (4) and at least one DC potential of the primary DC intermediate voltage circuit (4), said means being capable of limiting the DC output voltage of at least one of the inverters (7, 8) connected in series in the event of a malfunction in the DC load (2), the secondary DC intermediate voltage circuit (6), and/or at least one of the DC/DC converters (5a, 5b).