Weak-coupling modulation M-arc double-wire three-arc welding device and method

The invention provides a weak-coupling modulation M-arc double-wire three-arc welding device and method, and belongs to the technical field of welding, the weak-coupling modulation M-arc double-wire three-arc welding device comprises a first welding wire and a second welding wire, welding is started, the two welding wires are fed synchronously, and welding arcs are formed after the tail ends of the first welding wire and the second welding wire make contact with a welding workpiece; the first direct-current pulse power supply and the second direct-current pulse power supply which are controlled by the coordination control system alternately work at a set frequency, the frequency and amplitude of the high-frequency alternating power supply are independently adjusted, and the high-frequency alternating arc M exists independently. In the dynamic stable period, a first main arc AL and a high-frequency alternating arc M exist in half of each period at the same time; and the second main arc AR and the high-frequenc