| 摘要 |
A welding power supply (1) for supply of current to a welding electrode (2), and a method and a computer program for controlling such a welding power supply is described. The welding power supply (1) comprises an output (3) for output of current from the welding power supply (1), and a control unit (9) for controlling the welding power supply (1). The control unit (9) is arranged to control the welding power supply (1) to supply current to the output (3) in the form of a series of alternating positive current pulses (11), having a positive top value (Imax+), and negative current pulses (12), having a negative top value (Imax), and to lower the current in the current pulses from the negative top value (Imax) and the positive top value (Imax+) to a negative switch value (Ix-) and a positive switch value (Ix+), respectively, before switch between a positive current pulse (11) and a negative current pulse (12). The control unit (9) is arranged to control, in dependence of the current from the output and a first set point, the welding power supply (1) at least with regard to one of the point of time for lowering of the current in the current pulses and the level for at least one of the negative switch value (Ix-) and the positive switch value (Ix+). |
