An arc welding device includes memory in which a combination of a short circuit frequency, a peak current, and a peak current period is stored and determinator that determines a peak current and a peak current period based on a set short circuit frequency and the combination stored in memory. A welding output part performs welding output based on the peak current and the peak current period determined by determinator.

A power supply for welding, cutting and similar operations includes a dual two-switch forward converter. The converter has two inverter circuits coupled in parallel but controlled to provide output power in an interleaved fashion. To avoid walking of the circuits (which could result in different duty cycles and imbalance of the load sharing), control signals are determined and applied to a first of the inverter circuits, and on times of the first circuit is monitored, such as by augmenting a counter to determine the number of clock cycles the first circuit is on. The same duration is then used for commanding output from the second inverter circuit. The duty cycles of both circuits is thus ensured to be the same regardless of changes in the total output power.

A power supply to provide welding power. The power supply may include a dc source providing a direct current (DC) voltage input; a bridge circuit comprising a first plurality of switches, the bridge circuit being disposed on a primary side of the power supply and being coupled to receive the DC voltage input, and to output a primary voltage signal; a transformer coupled to the bridge circuit to transform the primary voltage signal to a secondary voltage signal; a synchronous rectification circuit to receive the secondary voltage signal and generate a welding signal, the synchronous rectification circuit comprising a second plurality of switches; and a controller coupled to the bridge circuit and synchronous rectification circuit, to coordinate operation of the plurality of primary switches with operation of the plurality of secondary switches.

A system for and method of controlling the heat input in a welding operation are provided. The system includes an arc welding power supply configured to output a welding waveform to a welding torch. The welding power supply includes a waveform generator to generate an output welding waveform. The power supply also includes a controller to optimize the output welding waveform based on a desired welding temperature. The optimization is performed by adjusting at least one of a power ratio and a duration ratio. The power ratio is a ratio of a power of a negative portion of the welding waveform to a power of a positive portion of the welding waveform, and the duration ratio is a ratio of a duration of a negative portion of the welding waveform to a duration of a positive portion of the welding waveform. The desired welding temperature is one of a temperature setpoint and a temperature range.

A welding-type system includes a wire feeder to provide an electrode wire to a welding-type torch. A welding-type power supply to provide power to one or both of the welding-type torch or the wire feeder. A controller is configured to control a sense voltage circuit to provide a sense voltage to charge a control capacitor, monitor a voltage feedback signal, determine that a wire feeder is activated based on a first change in the voltage feedback signal, control the switched mode power supply to provide a constant voltage output signal during a welding operation, control the switched mode power supply to provide the pulsed power output in response to completion of the welding operation, determine that the wire feeder is deactivated based on a second change in the feedback signal, adjust a pulse rate of the output signal to achieve an RMS value below a predetermined RMS level.

A power source applies an AC voltage between a welding torch and a workpiece. The power source includes an inverter circuit to switch between a positive polarity and an opposite polarity, a restriking circuit to apply a restriking voltage to an output of the inverter circuit when the positive polarity is switched to the opposite polarity, and a control circuit to control the restriking circuit. The restriking circuit includes a restriking capacitor to be charged with the restriking voltage, a charging circuit to charge the restriking capacitor with the restriking voltage, and a discharging circuit to discharge the restriking voltage in the restriking capacitor. The control circuit causes the charging circuit to start charging at a time of the opposite polarity, and to end charging after the opposite polarity is switched to the positive polarity.

A system for controlling arc length by regulating short circuit events during a welding process includes a welding power supply configured to conduct a free flight transfer pulsed arc welding process between a welding electrode and a workpiece, and a controller operatively connected to the welding power supply to control a welding waveform of the free flight transfer pulsed arc welding process. The controller is configured to automatically determine whether or not tethered incipient short circuits are included in said welding waveform, monitor a short circuit event characteristic during the free flight transfer pulsed arc welding process, and automatically adjust, based on said short circuit event characteristic, at least one parameter of said welding waveform to regulate tethered incipient short circuiting of the welding electrode to the workpiece during the free flight transfer pulsed arc welding process after determining that tethered incipient short circuits are included in said welding waveform.

Disclosed welding-type systems include a welding-type power source to generate output power for a periodic welding process that operates in an arc mode, an open circuit mode or a short circuit mode. A wire-feeder advances an electrode wire toward a workpiece. A controller adjusts the current to below a threshold value during the arc mode to result in the open circuit mode prior to occurrence of a short circuit event based on one or more welding process parameters. In some examples, the controller determines the occurrence of the short circuit event based on the one or more welding process parameters, and adjusts the current to rise above a second threshold level to adjust a heat generated in the welding wire in response to the occurrence of the short circuit.

A power supply for welding, cutting and similar operations includes a dual two-switch forward converter. The converter has two inverter circuits coupled in parallel but controlled to provide output power in an interleaved fashion. To avoid walking of the circuits (which could result in different duty cycles and imbalance of the load sharing), control signals are determined and applied to a first of the inverter circuits, and on times of the first circuit is monitored, such as by augmenting a counter to determine the number of clock cycles the first circuit is on. The same duration is then used for commanding output from the second inverter circuit. The duty cycles of both circuits is thus ensured to be the same regardless of changes in the total output power.

The present invention improves the stability of arc welding carried out by cyclical repetition of forward feed and reverse feed of a weld wire. An arc welding control method includes repeated forward feed and reverse feed at a weld wire feed rate, according to a prescribed cycle and a prescribed amplitude, and generation of short-circuit time intervals and arc time intervals to carry out welding, wherein the feed rate cycle and/or the amplitude are set automatically on the basis of the average feed rate and the welding rate, or the wire deposition amount per unit of weld length. Further, in the event that the amplitude has changed, feedback control of the forward feed-side shift amount is carried out in such a way that the average value of the feed rate is constant. In so doing, the feed rate cycle and amplitude are always set to optimal values.