A device for transmitting electric power between alternating voltage networks includes converters interconnected by direct current lines and provided each with several six-pulse conversion bridges. The six-pulse conversion bridges of one same converter are capable of being connected to an alternating voltage network associated with the converters via inductances differently phase-shifted. A control unit is provided to energize the valves of the six-pulse conversion bridges. The device is more economical and the converters are interconnected by a plurality of direct current circuits, each direct current circuit being galvanically separated from at least an alternating voltage network.