A welding system and method provide for generating a controlled waveform for welding power output, the waveform comprising a plurality of successive peak phases followed by a short circuit between a welding wire electrode and an advancing weld puddle. Each then present peak phase is regulated based upon at least the immediately preceding short circuit to control the short circuit that will occur following the then present peak phase. Some embodiments permit regulating at least one waveform phase based upon at least the immediately preceding short circuit to control the next short circuit that will occur, and regulating at least one short response phase based upon at least the immediately preceding short circuit to control the next short circuit that will occur.

In an arc welding control method for controlling welding in which a material of a base material is a galvanized steel sheet, a feed speed of a welding wire is alternately switched between a forward feed period and a reverse feed period, and a short circuit period and an arc period are repeated, during the arc period, a first arc period Ta1 during which a first arc current Ia1 is applied, a second arc period Ta2 during which a second arc current Ia2 is applied, and a third arc period Ta3 during which a third arc current Ia3 is applied are switched over time, and it is controlled so as to be Ia1>Ia2>Ia3. Constant voltage control is performed during the second arc period Ta2, and constant current control is performed during the first arc period Ta1.

A method and apparatus for providing welding-type power is disclosed. The system includes a power supply, a wire feeder, and a controller. The wire feed speed is reduced when the input current exceeds a value to prevent tripping circuit breakers on the power line the welder is connected to. The speed reduction is based on an average current draw exceeding a threshold. The output voltage is reduced if the input current exceeds a second threshold.

A method is performed in a welding or cutting system having a power inverter to generate an alternating current (AC) signal responsive to pulse width modulation (PWM) that is applied to the power inverter to control the AC signal. The method includes: upon detecting a power increase event in the welding or cutting system that necessitates an increase in the AC signal, controlling the PWM to cause the power inverter to increase the AC signal over multiple PWM cycles by: generating a first PWM cycle having a first period and a first on-time corresponding to a first duty cycle of the first PWM cycle that is greater than 50%; and generating a second PWM cycle having a second period that is greater than the first period and a second on-time corresponding to a second duty cycle of the second PWM cycle that is greater than 50%.

An arc welding method of a consumable electrode type generating arc between a tip end of welding wire and a to-be-welded portion by feeding welding wire to the to-be-welded portion of a base material while supplying welding current having average current of 300 A or larger to the welding wire, to weld the base material, includes: feeding the welding wire at a speed of the tip end being inserted into a space surrounded by a concave melted portion formed in the base material by the arc generated between the tip end and the to-be-welded portion; periodically alternating between a small current period where the welding current has a small average value and droplet is transferred from the tip end to a bottom part of the melted portion and a large current period where the welding current has a large average value and droplet is transferred from the tip end to a side part of the melted portion; and controlling the welding current in the large current period so that droplet transfer from the tip end to the side part is performed a plurality of times in each large current period.

A welding system is provided which utilizes a short arc welding method in which the waveforms have a positive polarity portion and negative portion to optimize heat input and provide heat and current control.

A pulse welding period alternately includes a first peak period in which a first peak current whose peak value is a first current value is caused to flow through a welding wire and a base period in which a base current having a second current value is caused to flow through the welding wire. During the base period, a second peak current whose peak current value is a sum of a second current value and a third current value and is smaller than the first current value is superimposed on the base current at a second pulse frequency. A second peak period in which the second peak current is caused to flow once is shorter than the first peak period. During the first peak period, a droplet is transferred from the welding wire toward a base material.

A method and apparatus for providing welding-type power includes an input circuit, a power circuit, and a controller. The input circuit receives input power and provides intermediate power. The power circuit has a power control input with at least one switch that responds to the control input. The power circuit receives the intermediate power and provides welding type output power. The controller has a set point input and a control output. The control output is connected to the power control input. The control circuit also includes a pwm module that responds to the user set point input and provided the control output. The pwm module can include a short duty cycle linearizing module. The pwm module can also include a short duty cycle charging ramp module.

The invention relates to an arc welding method using a consumable welding wire (1), wherein in successive welding cycles (SZ) during a welding process (P.sub.i) a certain welding current (I(t)) is applied to the welding wire (1) and the welding wire is moved with a certain wire conveying speed (v(t)) towards a workpiece (2) to be processed. The aim of the invention is to further improve the stability of the welding method. The aim is achieved, according to the invention, in that in the event of a change of the welding process (P.sub.1) to a welding process (P.sub.2) with an increased mean wire conveying speed (v.sub.mean) during a welding cycle (SZ) and/or with an increased mean welding current (I.sub.mean) during a welding cycle (SZ), a lowering phase (AP) is initiated, wherein in the lowering phase (AP) the welding current (I.sub.A(t)) is lowered for a specified duration (Δt.sub.A).

An electric arc welder and a method for performing a pulse welding process producing reduced spatter. The welder produces a current between an advancing electrode and a workpiece. The welder includes a short-detecting capability for detecting a short condition upon occurrence of a short circuit between the advancing electrode and the workpiece. The welder may also include a switching module in the welding circuit path of the welder having an electrical switch and a resistive path. Times of occurrence of short intervals can be tracked and a blanking signal can be generated based on the tracked short intervals to anticipate a next short interval in a next pulse period of the pulsed welding process. The blanking signal can be used to reduce a welding current in the welding circuit path by introducing additional resistance into the welding circuit path via the switching module, for example.