Systems and methods for controlled arc and short phase time regulation

Abstract

A welding type system includes: a welding type power supply configured to generate output power for an arc welding process; and a controller. The controller calculates representative durations of multiple short circuit events and / or arc events during the arc welding process. Each short circuit event and / or arc event includes a transition phase, an intermediate phase, and an end phase. The controller calculates the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the ramp-down time from the target current of the intermediate phase to the target current of the end phase associated with a given short circuit event or arc event. The controller controls the welding type power supply so as to adjust the duration of the transition phase, the intermediate phase, or the ramp-down time associated with the given short circuit event so that the sum is within a threshold range of the representative duration. Alternatively, the controller maintains the duration of the end phase less than a predetermined value.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application is a non-provisional patent application of U.S. Provisional Patent Application No. 62 / 799,342, filed on January 31, 2019, entitled “Systems and Methods for Controlled Arc and Short Phase Time Adjustment,” which is incorporated herein by reference in its entirety. Background Art

[0003] Welding is a process that is becoming more and more common in all industries. Conventional systems and methods for joining processes such as welding, brazing, gluing and / or other joining operations require a significant investment in equipment, such as machining, displays, implements, welding tools, sensors and / or other equipment.

[0004] Conventional short-circuiting gas metal arc welding (GMAW), also known as metal inert gas (MIG) welding, is a welding process in which an electric arc is formed between an electrode and the metal parts to be welded. The electric arc generates heat that melts the metal parts. After the molten metal parts cool, the metal parts join and form a weld. Electrical and / or physical parameters can be measured, and the results of these measurements can be provided to the welder and / or control system and control circuitry as process feedback and system feedback during the welding operation. The welder and / or control system and control circuitry can use this feedback information to adjust the welding parameters in real time while welding, thereby improving the welding process.

[0005] Advanced forms of MIG welding are based on the generation of cyclic pulses that can result in a controlled short circuit between an advancing wire electrode and a weld pool comprising the molten metal of the workpiece and the wire electrode. That is, various pulse schemes can be implemented in which current pulses and / or voltage pulses are commanded by a power supply control circuit system to adjust the formation and deposition of metal droplets (and / or sprays and / or balls) from the welding wire, to maintain a desired heating profile and cooling profile of the weld pool, to control the short circuit between the wire and the weld pool, and so on.

[0006] Although effective in many applications, such pulsed and short-circuit welding schemes may have disadvantages. For example, depending on the transition mode, these processes may limit travel speed, generate excessive spatter requiring timely cleaning of the welded workpiece, provide non-optimal penetration, or any combination of these and other effects. Moreover, certain pulse processes (such as processes operating in a spray mode of material transfer) may overheat for certain applications. Other processes, such as short-circuit processes, may result in cooling, but may again generate spatter and other undesirable welding effects.

[0007] Furthermore, in certain welding situations and when using certain welding electrodes, a pulse welding process that is trained to implement a cyclic short circuit between the electrode and the workpiece may add too much energy to the weld. For example, for a wire electrode with a core layer, the electrode may be heated by the excess current added to the wire, especially because the welding current tends to flow through the wire sheath (which may be more easily melted than a solid wire). As a result, the arc may flare (i.e., become longer). However, in order to cross the gap, reduce burn-through, and increase travel speed, it may be desirable to maintain the arc length at a minimum. Unfortunately, this can cause the wire to short-circuit to the ongoing weld pool and require additional current to clear the short circuit, which also causes the wire sheath with a core layer to heat up and cause the arc to flare, resulting in a high power output using a large power source.

[0008] Therefore, there is a need for improved welding strategies that allow welding in both pulsed and short-circuit waveform regimes while improving weld quality and flexibility. Summary of the invention

[0009] The present disclosure relates generally to welding machines, and more particularly to a welding machine configured to control a short circuit event of an arc welding operation by adjusting the duration and / or current associated with one or more phases of the short circuit event or arc event. As a result, the controlled short circuit produces less spatter and lower current than conventional systems.

[0010] According to an exemplary embodiment, a welding method includes: generating a control waveform for welding power output, the waveform including a plurality of consecutive peak phases followed by a short circuit between a welding pool and an advancing wire electrode; and adjusting the duration of each current peak phase based at least on the duration of one or more phases of a previous short circuit event to control the short circuit that will occur after the current peak phase.

[0011] In some examples, these methods and systems allow: adjusting at least one waveform phase based at least on a previous short circuit to control the next short circuit that will occur; and / or adjusting at least one short circuit response phase based at least on a previous short circuit to control the next short circuit that will occur. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 is a diagrammatic representation of an exemplary arc welding system according to aspects of the present technology, showing a power supply coupled to a wire feeder to perform a controlled short circuit welding operation.

[0013] Figure 2 is used for Figure 1 A diagrammatic representation of exemplary control circuitry components for a welding power supply of the type shown.

[0014] Figure 3 is a graphical representation of an exemplary waveform for controlled short circuit welding according to the present disclosure.

[0015] Figure 4 is a graphical representation of another exemplary waveform for controlled short circuit welding according to the present disclosure.

[0016] Figure 5 is a graphical representation of yet another exemplary waveform for controlled short circuit welding according to the present disclosure.

[0017] Figure 6 is a flow chart illustrating a welding scheme according to the present disclosure. DETAILED DESCRIPTION

[0018] The present disclosure describes systems and methods for achieving controlled short circuits by time adjustment of one or more phases of arc events, short circuit events, or a combination of these two events. The time adjustment can be based on representative (e.g., average) durations of arc events and / or short circuit events to control short circuit clearing to occur at a desired current level.

[0019] For example, short circuit clearing prediction can be based on process feedback variables. If the current level is not sufficiently reduced before the short circuit clearing event, the higher current level will cause spatter. In order to reduce the amount of spatter, the duration of one or more stages of the short circuit event can be adjusted so that the current is at a desired value when the short circuit clearing occurs.

[0020] In some examples, the target current level in one or more stages of a short circuit can be adjusted. When the target peak current of the previous stage is reduced, the ramp-down time to the target threshold current of the next stage is shortened. The result is that the short circuit clearing event occurs at the target current rather than at a current level between the target peak current and the threshold current.

[0021] In some disclosed examples, the duration of a short circuit event can be described for three or more different stages (a transition stage, an intermediate stage, and an end stage). Each stage has an independently determined target current, current ramp rate, and / or duration. Additionally or alternatively, each stage can have an independently determined target wire feed speed (WFS) and WFS ramp rate that adjusts the speed and / or acceleration of the wire as it advances toward and / or retracts from the workpiece.

[0022] If the short circuit duration is less than the sum of the duration of the transition phase, the intermediate phase, and the time required to reduce the current from the peak current level to the background current level, the short circuit clearing event occurs at a current value higher than the expected background current level. Inconsistent timing of short circuit clearing and the associated current levels may adversely affect the stability of the welding process.

[0023] To avoid short circuit clearing at current levels above the background level, the controller can use representative short circuit clearing event durations (e.g., average values) to adjust one or more characteristics of the short circuit phase (e.g., duration, current level) to avoid clearing the short circuit before the background current is reached.

[0024] The short circuit cycle alternates between short circuit events and arc events. In a manner consistent with the description of short circuit control, the arc events can be adjusted to control the short circuit clearing to occur. For example, it is desirable that molten droplets from the welding wire enter the weld pool at relatively low current levels during the MIG welding process. If the current level is too high, the normal "wetting" action between the droplet and the weld pool will be interrupted by the high Lorentz "pinch" force at the droplet / weld pool interface. This interruption of the droplet transfer process may cause the process to discharge large spatter droplets.

[0025] To avoid such unwanted spatter, multiple phases of the arc event are set so that a predetermined current level is reached before the short circuit event. In particular, the multiple phases of the arc event have the same independently adjustable parameters as described with respect to the short circuit phase. For example, the current level can be reduced much faster during the arc phase because a higher voltage is available during the arc phase to drive energy from the output inductor.

[0026] Thus, in a manner similar to that described with respect to short circuit events, arc events may be regulated according to a control scheme implemented by a controller.

[0027] The controller is configured to calculate the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the ramp-down time from the peak target current level of the intermediate phase to the target background current level of the end phase (when the short circuit event occurs).

[0028] The controller is configured to control the power supply to adjust the characteristics of one of the transition phase, the intermediate phase or the ramp-down time, so that the sum of the duration of the transition phase, the duration of the intermediate phase and the duration of the ramp-down time is less than the representative duration. As described above, the current level (e.g., the peak current level and the background current level) can also be adjusted to reduce the current decay time to achieve a similar effect. The duration and / or target current level of any or all of the phases associated with the short circuit event can be adjusted.

[0029] Additionally or alternatively, current levels (eg, peak current levels and / or background current levels) may be adjusted to reduce current decay time to achieve a similar effect. The duration and / or target current level of any or all of the phases associated with an arc event may be adjusted.

[0030] Additionally or alternatively, the phase current and time parameters may be fixed and the wire feed speed may be adjusted to vary the duration of one or more of the phases associated with short circuit events and / or arc events.

[0031] The systems and methods described herein are used to increase arc welding process stability and reduce spatter generation during welding. The resulting process is more responsive to dynamically changing process variables such as contact tip to workpiece distance (CTWD), torch travel speed, torch angle, workpiece material thickness, joint configuration, and other variables.

[0032] Depending on the welding process being performed, it may be desirable to heat the wire (e.g., via the Joule heating effect) by the current flowing through the wire. Therefore, the average short circuit current needs to be at an elevated level. Therefore, in order to maintain current for sufficient Joule heating of the wire while limiting the amount of spatter during a short circuit clearing event, the current level is dynamically adjusted so that the current is at a threshold level at the time of the clearing event.

[0033] In some examples, power is provided from a switch mode power supply. Due to the physical limitations of such a power supply, the rate at which the current can be reduced is limited by the magnitude of the welding process voltage. In the case of a short circuit, this voltage is very low, which corresponds to a low current decay rate.

[0034] As used herein, the term "welding-type power" refers to power suitable for welding, plasma cutting, induction heating, CAC-A, and / or hot wire welding / preheating (including laser welding and laser cladding). As used herein, the term "welding-type power supply" refers to any device capable of providing power for welding, plasma cutting, induction heating, CAC-A, and / or hot wire welding / preheating (including laser welding and laser cladding) when power is applied thereto, including but not limited to inverters, converters, resonant power supplies, quasi-resonant power supplies, etc., as well as control circuits and other auxiliary circuits associated therewith.

[0035] As used herein, the term "pulse welding" includes welding performed with output power that is pulsed between a higher peak and a lower background, typically at a controlled frequency, and the pulse welding is performed in an arc state.

[0036] As used herein, the terms "periodic" and / or "cyclical" welding processes and / or outputs include welding outputs that may be characterized as a series of periods and / or cycles, where each cycle may be the same, similar, or different.

[0037] As used herein, the term "wire feeder" includes the motor or mechanism that drives the wire, the mounting for the wire, the controls related thereto, and the associated hardware and software.

[0038] As used herein, the term "bidirectional wire feeder" includes a motor or mechanism for driving the wire, a mounting for the wire, controls associated therewith, and associated hardware and software, and the bidirectional wire feeder is capable of both advancing and retracting the wire. The bidirectional wire feeder can be used in periodic and / or cyclic welding processes.

[0039] As used herein, the term "controller" or "control circuitry" includes digital and / or analog circuits, discrete or integrated circuits, microprocessors, DSPs, FPGAs, etc., and / or software, hardware, and firmware located on one or more boards for controlling all or a portion of a welding-type system or device such as a power supply, power source, engine, or generator.

[0040] As used herein, "circuit" or "circuitry" includes any analog and / or digital components, power and / or control elements (such as microprocessors, digital signal processors (DSPs), software, etc.), discrete components and / or integrated components, or multiple parts and / or combinations thereof.

[0041] As used herein, the term "energy storage device" is any device that stores energy, such as, for example, a battery, a supercapacitor, or the like.

[0042] As used herein, the term "memory" includes volatile and non-volatile memory, and may be an array, a database, a list, and the like.

[0043] As used herein, the term "welding torch" or "welding-type tool" may include a handheld or robotic welding torch, welding gun, or other device for generating a welding arc.

[0044] As used herein, the term "welding mode" or "welding operation" is the type of process or output used, such as CC, CV, pulse, MIG, TIG, spray, short circuit, etc.

[0045] As used herein, the term "boost converter" is a converter used in a circuit that increases voltage. For example, a boost converter can be a step-up converter (such as a DC-DC power converter) that can step up voltage while stepping down current from its input (e.g., from an energy storage device) to its output (e.g., a load and / or an attached power bus). This is a switch mode power supply.

[0046] As used herein, the term "buck converter" (eg, step-down converter) refers to a power converter that steps down a voltage (eg, while stepping up a current) from its input to its output.

[0047] In the disclosed example, a welding-type system includes: a welding-type power supply configured to generate output power for an arc welding process; and a controller. The controller is configured to calculate a representative duration of multiple short circuit events during the arc welding process, wherein each short circuit event includes a transition phase, an intermediate phase, and an end phase. The controller calculates the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the ramp-down time from the target current of the intermediate phase to the target current of the end phase associated with a given short circuit event. The controller controls the welding-type power supply so as to adjust the duration of the transition phase, the intermediate phase, or the ramp-down time associated with a given short circuit event so that the aforementioned sum is less than the representative duration.

[0048] In some examples, a welding-type system includes a controller, wherein the controller is configured to receive a signal from a sensor, the signal representing a characteristic of each short circuit event in the plurality of short circuit events during an arc welding process. In an example, the system characteristic includes at least one of current, duration, or voltage.

[0049] In an example, a welding-type system includes a controller for measuring the duration of an end phase of a given short circuit event based on one or more of the characteristics. In an example, a welding-type torch performs an arc welding process, the welding-type torch including a wire feeder configured to drive an electrode to a workpiece via the welding-type torch. In an example, a welding-type system includes a wire feeder, wherein the wire feeder is configured to control electrode advancement or retraction.

[0050] In some examples, the controller adjusts the duration of the ramp-down during the end phase so that a short circuit clearing event associated with a given short circuit event occurs at a target current in the end phase. In an example, the target current in the intermediate phase is greater than the target current in the end phase. In an example, the controller adjusts one of the target current in the intermediate phase or the target current in the end phase to reduce the ramp-down time and / or the duration of the end phase. In some examples, the duration of the end phase is maintained at a level less than a predetermined value. In an example, the controller adjusts the duration of two or more of the transition phase, the intermediate phase, and the ramp-down time associated with a given short circuit event.

[0051] In an example, a welding-type system includes a power supply, wherein the power supply includes a switch-mode power supply. In some examples, a ramp-down rate is limited by a voltage amplitude associated with an output power from the switch-mode power supply for an arc welding process. In an example, each short circuit event includes at least two intermediate stages, each intermediate stage including a respective target current level.

[0052] In some disclosed examples, a welding-type system includes: a welding-type power supply configured to generate an output power for an arc welding process; and a welding torch including a wire feeder configured to drive an electrode to advance or retract during the arc welding process. The system also includes a controller configured to calculate a representative duration of multiple short circuit events during the arc welding process, wherein each short circuit event includes a transition phase, an intermediate phase, and an end phase. The controller calculates the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the ramp-down time from the target current of the intermediate phase to the target current of the end phase associated with a given short circuit event. When the electrode advances or retracts during the transition phase, the intermediate phase, or the end phase, the controller adjusts the wire feed speed and / or acceleration of the electrode to adjust the time of the short circuit event so that the aforementioned sum is less than the representative duration.

[0053] In an example, the controller increases the acceleration when the electrode is retracted during a transition phase, an intermediate phase, or an end phase associated with a given short circuit event. In an example, the welding-type system includes a controller, wherein the controller is configured to reduce the acceleration when the electrode is advanced during an arc event associated with a given short circuit event. In an example, the welding-type system includes a controller, wherein the controller is configured to adjust the length of the electrode extending from the welding torch during the arc event to control the arc length.

[0054] In some disclosed examples, a welding-type system includes: a welding-type power supply configured to generate output power for an arc welding process; and a controller configured to calculate representative durations of multiple arc events during the arc welding process, wherein each arc event includes a transition phase, an intermediate phase, and an end phase. The controller calculates the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the ramp-down time from the target current of the intermediate phase to the target current of the end phase of a given arc event. The controller adjusts the duration of one of the transition phase, the intermediate phase, or the ramp-down time associated with the given arc event so that the aforementioned sum is within a threshold range of the representative duration. Additionally or alternatively, the duration of the end phase is maintained at a level less than a predetermined value.

[0055] In an example, a welding-type system includes a welding-type power supply, wherein the welding-type power supply includes a switch-mode power supply to generate output power. In some examples, the welding-type system includes a controller, wherein the controller is configured to adjust a target current of an intermediate stage associated with a given arc event.

[0056] Figure 1 An example arc welding system 100 is shown for performing a controlled short circuit (CSC) welding operation. Figure 1 In the example of an arc welding type system shown, a power supply 10 and a wire feeder 12 are connected via a conductor or conduit 14. In the example shown, the power supply 10 is separated from the wire feeder 12 so that the wire feeder can be located at a distance from the power supply and near the welding location. However, in some examples, the wire feeder can be integrated with the power supply 10. In this case, the conduit 14 will be internal to the system. In examples where the wire feeder 12 is separated from the power supply 10, terminals are typically provided on the power supply and the wire feeder 12 to allow the conductor or conduit to be connected to the system, thereby allowing power and gas to be provided from the power supply 10 to the wire feeder 12, and allowing data to be exchanged between the two devices.

[0057] The system 100 is configured to provide wire, power, and shielding gas to a welding tool or torch 16. The tool 16 can be of many different types and can allow the welding wire 42 (e.g., electrode wire) and gas to be delivered to a position adjacent to a workpiece, substrate, or platform 18. A second conductor extends to the welding workpiece to complete the circuit between the power supply and the workpiece. In the context of additive manufacturing, the substrate 18 provides a foundation on which a part 78 including a layer 82 is formed by applying a metal droplet 80. The disclosed controlled short circuit welding system 100 can employ a switch 13 to provide an alternative current path for one or more welding processes. For example, employing a switch 13 provides an opportunity to adjust the current decay rate when transitioning from a high / peak current to a lower current value. In some examples, the reduced ramp-down duration results in a shorter sum of phase times (such as the phase time between the intermediate phase and the end phase in an arc event and / or a short circuit event). In some examples, the duration of the end phase is maintained at a level less than a predetermined value (e.g., 1 millisecond).

[0058] The welding system 100 is configured to be set by an operator and / or according to welding sequence selection data, for example, via an operator interface 20 provided on the power supply 10. The operator interface 20 will typically be incorporated into the front panel of the power supply 10 and may allow selection of settings such as the welding process, the type of wire to be used, voltage and current settings, etc. In particular, the system is configured to allow welding with various steel welding wires, aluminum welding wires, or other types of welding wires fed through the tool 16. In addition, the system is configured to employ welding wires having various cross-sectional geometries (e.g., circular, generally flat, triangular, etc.). These welding settings are transmitted to the control circuit 22 within the power supply. The system may be particularly suitable for implementing welding schemes configured for certain electrode types.

[0059] Processing instructions for the welding process may be provided by a welding sequence program, such as stored on a memory accessible to a processor / control circuit 22 associated with the power supply 10. In this case, the sequencer may employ stored information (e.g., associated with a desired product configuration and / or process, including historical data) and / or may be user-customizable. For example, information associated with a specific design corresponding to the part 78 (e.g., thermal distribution, material properties, system control parameters, etc. associated with the part 78) may be stored in a memory and / or provided via a network interface. Thus, this information may be used to control the operation of the system to facilitate the formation of the part 78, such as by controlling the power output from the power supply 10, the wire feeder motors 48, 54, etc.

[0060] The control circuit 22 operates to control the generation of welding power output supplied to the welding wire 42 for performing the desired welding operation. In an example, the control circuit 22 can be adapted to adjust a pulsed MIG welding scheme that promotes short-circuit transfer of molten metal to the part 78 without adding excessive energy to the part 78 or the welding wire 42. In the "short-circuit" mode, droplets of molten material are formed on the welding wire 42 under the influence of heating generated by the welding arc and are periodically transferred to the part 78 due to contact or short circuiting between the welding wire 42, the droplets 80 and the part 78. Note that herein in this disclosure, the part 78 is sometimes referred to as a workpiece, a weldment, or a welded workpiece.

[0061] In this manner, the system and / or control circuit 22 controls the welding of the part 78 by adjusting one or more welding process parameters of the system during the welding process. The welding process parameters may include, but are not limited to, wire feeder speed, wire feeder direction, travel speed, power output, process mode, deposition path, deposition sequence, torch angle, etc.

[0062] In addition, the sensor(s) 70 may measure operating parameters associated with the operation of the system (e.g., current, voltage, inductance, phase, impedance, power, inductance, wire speed, acceleration, orientation, position, etc.). The sensed operating characteristics (e.g., voltage, current, temperature, shape, speed, etc.) may be provided to the control circuit 22 or other controller (e.g., the control circuit 32, a controller associated with the control system 72, etc.) to further control the welding process.

[0063] Power is typically applied to the wire electrode 42 from a power supply through a welding cable 52. Similarly, shielding gas is fed through the wire feeder and welding cable 52. During a welding operation, the welding wire 42 is advanced through the sheath of the welding cable 52 toward the tool 16. Within the tool 16, a second wire feeder motor 53 includes a roller 54 that may be provided with an associated drive roller that may be adjusted to provide a desired wire feed speed and / or direction.

[0064] A control system 72 may be employed to adjust, for example, the movement and position of the tool 16 based on the control circuits 22, 32 and information from the sensor(s) 70. In an example, the control system 72 may communicate with the power supply 10, the wire feeder 12, and / or the tool 16 via one or more cables 75. Thus, power and / or information may be provided and / or exchanged via the cables 75 to control the welding process. In particular, the control system 72 may employ one or more arms 74 having one or more actuators 76 (e.g., servomotors, joints, etc.). In this manner, the control system 72 may issue commands to finely control the attached tool 16 in six degrees of freedom during the welding operation, including travel speed, tool position, distance from the part 78, etc. The control system 72 may include one or more sensors for sensing welding process parameters, which may communicate with the control circuits 22, 32 to further facilitate the formation of the part 78.

[0065] In some examples, the control circuit 22, 32 can provide signals to the wire feeder 12, the power supply 10, and / or the control system 72 to enable the welding process to be started and stopped according to the specific application or welding process. That is, when the process is started, gas flow can be started, the wire can be fed, and power can be applied to the welding cable 52 and applied to the feeding welding wire 42 through the tool 16. The work cable and clamp 58 allow the circuit from the power source through the welding torch, the electrode (wire), and the part 78 to be closed for maintaining the welding arc during operation.

[0066] The present arc welding system allows for controlling the promotion, occurrence, continuation and interruption of short circuit events between the weld pool and the advancing wire electrode by controlling the successive voltage levels and / or current levels and / or pulse durations based on previous current and duration measurements. In particular, the current waveform is adjusted based on one or more of the above short circuit events or aspects of the short circuit events, such as their duration.

[0067] The control circuit 22 is coupled to a power conversion circuit 24. The power conversion circuit 24 is adapted to generate an output power, such as a pulse waveform applied to the welding wire 42 at the tool 16. Various power conversion circuits may be employed, including choppers, boost circuits, buck circuits, inverters, converters, etc. The configuration of such circuits may be of a type known in the art as such. As indicated by arrow 26, the power conversion circuit 24 is coupled to a source of electrical power. The electrical power applied to the power conversion circuit 24 may be derived from an electrical grid, but other sources of electrical power may also be used, such as power generated by an engine driven generator, a battery, a fuel cell, or other alternative sources of electrical power. Figure 1 The power supply shown in FIG. 1 may also include an interface circuit 28 configured to allow the control circuit 22 to exchange signals with the wire feeder 12 .

[0068] In this manner, the control circuit 22 (and / or the control circuit 32) is configured to control short circuit events by controlling time adjustments to one or more stages of an arc event, a short circuit event, or a combination of both events, as disclosed herein. For example, the time adjustments may be based on representative (e.g., calculated average, determined average, and / or historical average) durations of arc events and / or short circuit events to control short circuit clearing to occur at a desired current level.

[0069] In some examples, one or more of the phases of short circuit events and arc events have individually determined representative durations. In addition, each phase can be associated with a desired target range of threshold durations. Thus, the control circuit can adjust the duration of one of the transition phases, intermediate phases, or end phases associated with a given event so that the respective phases are within a range of threshold durations (e.g., stored in a storage device, input from a networking system, etc.). Additionally or alternatively, the phase durations can be adjusted to ensure that the total duration of all associated phases is within a threshold range of representative durations, and / or that the duration of the end phase is maintained at a level less than a predetermined value (e.g., 1 millisecond). The predetermined value can be a range of values ​​or a selected threshold value about a predetermined value, which is selected for a variable in a particular welding process (e.g., wire type, material type, torch type, etc.) and / or selected in response to a command (e.g., from an operator). Limiting the duration of the end phase can be achieved by limiting the amount of time spent in the relatively low power end phase (e.g., Figures 3 to 5 As shown) to benefit the Joule heating of the electrode wire 42 and / or facilitate the complete deposition of the electrode wire 42.

[0070] For example, the control circuit 22 can generate a short circuit clearing prediction, which can be based on process feedback variables (based on inputs from one or more sensors 70). If the current level is not sufficiently reduced before the short circuit clearing event, the higher current level will cause spatter. In order to reduce the amount of spatter, the control circuit 22 can adjust the duration of one or more stages of the short circuit event so that the current is at a desired value when the short circuit clearing occurs.

[0071] In some disclosed examples, the duration of the short circuit event can be described for three or more different stages (a transition stage, an intermediate stage, and an end stage). Each stage has an independently determined target current, current ramp rate, and / or duration. Additionally or alternatively, each stage can have an independently determined target wire feed speed and wire feed speed ramp rate (e.g., provided via coordination between the control circuit 22 and the control circuit 32), which adjusts the speed and / or acceleration of the wire 42 as it advances toward and / or retracts from the workpiece 18.

[0072] As disclosed herein, to avoid short circuit clearing at current levels above background levels, the controller 32 can utilize representative short circuit clearing event durations (e.g., average values) to adjust one or more characteristics of the short circuit phase (e.g., duration, current level) to avoid clearing the short circuit before the background current is reached.

[0073] The wire feeder 12 may include complementary interface circuitry 30 coupled to the interface circuitry 28. In some examples, a multi-pin interface may be provided on both components, with a multi-conductor cable extending between the interface circuitry to allow information such as wire feed speed, process, selected current, voltage, or power level to be set on the power supply 10, the wire feeder 12, or both.

[0074] The wire feeder 12 may also include a control circuit 32 coupled to the interface circuit 30. As described below, the control circuit 32 allows the wire feed speed to be controlled according to the operator's selection or stored sequence instructions, and allows these settings to be fed back to the power supply via the interface circuit. The control circuit 32 is coupled to an operator interface 34 on the wire feeder, which allows the selection of one or more welding parameters, particularly the wire feed speed. The operator interface may also allow the selection of welding parameters such as process, type of wire used, current, voltage or power settings. The control circuit 32 may also be coupled to a gas control valve 36, which adjusts the flow of shielding gas to the welding torch. Typically, this gas is provided during welding and can be turned on immediately before welding and turned on in a short time after welding. The gas applied to the gas control valve 36 may be provided in the form of a pressurized bottle, as indicated by reference numeral 38.

[0075] The wire feeder 12 includes components for feeding wire to the tool 16 and thereby to the welding application under the control of the control circuit 32. For example, one or more spools 40 of welding wire are contained in the wire feeder. The welding wire 42 is unwound from the spool and gradually fed to the tool 16. The spool may be connected to a clutch 44, which is disengaged from the spool when the wire is fed to the tool. The clutch 44 may also be adjusted to maintain a minimum friction level to prevent the spool 40 from rotating freely. A first wire feeder motor 46 may be disposed in a housing 48, which engages a wire feed roller 47 to advance the wire from the wire feeder 12 toward the tool 16.

[0076] exist Figure 1In an example of the embodiment of the present invention, the movable buffer 60 may include a first portion 62 and a second portion 64, wherein at least one of the first portion and the second portion is configured to move relative to the other of the first portion and the second portion in response to a change in the amount of welding wire 42 between the first wire feeder motor 46 and the second wire feeder motor 53. The sensor 66 (e.g., one or more sensors) is configured to sense the relative movement or displacement between the first portion and the second portion and provide the sensor data to the control circuit (e.g., the control circuit 22, 32) to adjust the speed and / or direction of the welding wire 42 in response.

[0077] In practice, at least one of the rollers 47 is mechanically coupled to a motor and is rotated by the motor to drive the wire from the wire feeder, while the cooperating rollers apply a bias toward the wire to maintain good contact between the two rollers and the wire. Some systems may include multiple rollers of this type. A tachometer 50 or other sensor may be provided to detect the speed of the first wire feeder motor 46, roller 47, or any other associated component to provide an indication of the actual wire feeding speed. The signal from the tachometer is fed back to the control circuit 32, such as for continuous or periodic monitoring, calibration, etc. In some examples, the system includes a wire spool motor for rotating the wire feeder, which can be similarly adjusted to increase or decrease the amount of wire between the wire feeder motors.

[0078] In some examples, the wire feeder 12 can be configured to reverse the direction of the welding wire 42 (i.e., a bidirectional wire feeder). In addition, although described as operating with two wire feeders and / or wire feeder motors (e.g., wire feeder motors 46 and 53), the system can operate with a single wire feeding unit to advance and / or retract the wire during a welding operation (e.g., forming of part 78). Additionally or alternatively, in some examples, one wire feeder can be configured to advance the welding wire 42 while the other wire feeder is configured to reverse the direction of the welding wire. In this example, as disclosed herein, one or more control circuits (e.g., control circuits 22, 32) coordinate the operation of the two wire feeders to implement a controlled short circuit welding process in the welding system.

[0079] In the disclosed example, a control circuit (e.g., control circuit 22, 32) receives a feedback signal corresponding to a contact force applied to the wire 42 from one or more drive rollers 47, 54. Then, in response to the contact force falling outside the range of the threshold contact force value, the control circuit commands the actuator and / or mechanical device to adjust the contact force. For example, the control circuit (e.g., control circuit 22, 32) can command the actuator to automatically adjust the contact force via a motor (e.g., motor 46) or an associated clutch, solenoid, piezoelectric device, and / or other electromechanical device. The result is to adjust the contact force applied to the welding wire 42 from one or more drive rollers 47, 54. For example, the actuator and / or mechanical device can cause the position of the drive roller to change, such as increasing or decreasing the distance between multiple drive rollers through which the wire is fed. Additionally or alternatively, the position of the drive roller can be adjusted to change the area on the surface of the drive roller that contacts the wire.

[0080] Other system arrangements and input schemes may also be implemented. For example, the welding wire may be fed from a bulk storage container (e.g., a drum) or from one or more spools external to the wire feeder. Similarly, the welding wire may be fed from a "spool gun" in which the spool is mounted on or near the welding torch in a spool gun configuration. As described herein, the wire feed speed setting may be input via an operator input 34 on the wire feeder or an operator interface 20 of the power supply or via both the operator input 34 and the operator interface 20. In a system with a wire feed speed adjustment on the welding torch, this may be an input used for such a setting.

[0081] Although described with respect to an arc welding type system, the disclosed system may be implemented in conjunction with various techniques to perform various types of welding processes.

[0082] Therefore, as regards Figure 1 As described, the welding-type system 100 may include a welding-type power source 10 configured to generate output power for an arc welding process, such as to power one or more of a wire feeder 12, a robotic system 74, perform arc welding via a tool 16, etc. The wire feeder 12 may be a bidirectional wire feeder configured to advance or retract the wire 42 to or from the workpiece 18. The sensor 70 measures one or more welding process parameters and provides such measurements to a controller (e.g., control circuit 22, control circuit 32, control system 72, etc.), which commands an operation, such as in response to one or more welding process parameters exceeding one or more thresholds corresponding to a short circuit clearing event during a welding / additive manufacturing operation.

[0083] Figure 2 An example control circuit is shown, which is configured to Figure 1The control circuitry 22 shown functions in a system of a similar type as that described above. The overall circuitry includes the operator interface 20 discussed above and the interface circuitry 28 for transmitting and receiving parameters to and from downstream components (generally indicated by reference numeral 29), such as the wire feeder 12, the welding torch 16, and various sensors and / or actuators. The circuitry includes processing circuitry 21 (which itself may include one or more special purpose or general purpose processors) configured to execute welding regimens, perform calculations on waveforms implemented in welding regimens, etc. The processing circuitry 21 is coupled to driver circuitry 23, which converts control signals from the processing into drive signals that are applied to power electronic switches of the power conversion circuitry 24. Generally, the driver circuitry 23 reacts to the control signals from the processing circuitry 21 to allow the power conversion circuitry 24 to generate controlled waveforms for pulsed welding regimens of the type disclosed herein. The processing circuit 21 will also be associated with a memory circuit system 25, which can be composed of one or more types of permanent data storage devices and temporary data storage devices. The memory circuit system is used, for example, to provide implemented welding plans, store welding parameters, store welding settings, store error logs, etc.

[0084] Figure 3 An exemplary graphical representation 80 of a current waveform 82 and a voltage waveform 84 during a phase of a short circuit event as described herein is shown. For example, as disclosed herein, the waveforms 82 and / or 84 may be generated by the control circuitry 22 and / or 32 to issue commands to the power output from the welding power supply 12. Further, these commands may be generated by one or more remote computing platforms, such as transmitted via one or more data channels (e.g., via a network interface, a networked computer, etc.).

[0085] As shown in the figure, the process alternates from arc events to short circuit events. Figure 3 As shown, at voltage 86 and current 88, the process occurs at time t 1 Approaching the transition from the previous arc event to the short circuit event. Although the current level 88 is shown as corresponding to the background current level during the transition phase P1, the current can be adjusted as needed (e.g., to adjust the heat input). When the electrode wire 42 contacts the workpiece 18, the voltage drops rapidly to a low voltage level 92 as shown by reference numeral 90. As the voltage drops during the transition phase (P1), the arc event transitions to a short circuit event, and the current level rises 94 to a predetermined peak current level 96 associated with the intermediate short circuit phase (P2).

[0086] In addition, if Figure 4Depicted and described further below, a second intermediate phase (P2B) may be included, in which case each phase includes a target current level, such as a first peak current level 96 associated with the first intermediate phase (P2A) and a second peak current level 100 associated with the second intermediate phase (P2B).

[0087] Return to reference Figure 3 , the ramp-down time (indicated by reference numeral 102) from the previous current level 96 can be defined by the time required to transition between target current levels. Thus, adjustment of one or two target current levels (e.g., peak current, background current, etc.) limits the duration of the transition between these two current levels. Additionally or alternatively, the ramp-down rate 102 can correspond to one or more characteristics of a power source (e.g., a switch-mode power supply), characteristics of the cable(s) 75, and / or can be adjusted by a user and / or a sequencer.

[0088] During the intermediate phase (P2), the short circuit event progresses to the point where the molten ball transfer is about to occur. In order for the short circuit to clear, at time t 3 With t 4 , the commanded current level is reduced from the peak current level 96 to a lower (e.g., background) current level 104. Likewise, the current decay rate (represented as 102) may be limited by various factors. Once the background current level 104 is reached, short circuit clearing occurs in the end phase (P3) of the short circuit event. As disclosed herein, the duration of the end phase may be maintained at a level less than a predetermined value (e.g., 1 millisecond). Such a value may be programmed, set by an operator, stored in a memory device, provided via a remote computing platform, informed by historical data, or provided from another suitable source. At time t 4 , the cycle advances to the arc event stage until the cycle repeats. As shown, the voltage level increases from the low level 92 at a ramp rate represented by reference numeral 108 to a peak voltage level 110 sufficient to sustain an arc.

[0089] like Figure 3 and Figure 4 As shown, the low voltage level can be maintained at a single level (e.g., low voltage 92), or the low voltage level can be adjusted and / or achieved by controlling the current level to a second voltage level 106 or a third voltage level 107. As shown, Figure 4 The short circuit event includes a first intermediate stage (P2A) and a second intermediate stage (P2B). However, according to the present disclosure, a single intermediate stage, or three or more intermediate stages may be employed. In addition, the transition between the stages may be initiated by commanding different current levels, wherein the voltage level is responsive to the current command.

[0090] Figure 4 A graphical representation 80 of a current waveform 82 and a voltage waveform 84 during the phases of a short circuit event as described herein is shown. As shown, the process is cyclical and at time t 1 The arc event transitions to a short circuit event and at time t 5 The transition from a short circuit event to an arc event. Therefore, at voltage 86 and current 88, the process is close to Figure 4 The transition from the previous arc event to the short circuit event shown. When the electrode contacts the workpiece, the voltage drops rapidly (as shown in the figure 90) to a low voltage level 92. As shown, as the arc event transitions to the short circuit event, the voltage drops during the transition phase (P1). The current level rises 94 to a predetermined peak current level 96 associated with the first intermediate short circuit stage (P2A). In addition, a second intermediate stage (P2B) may be included. As described herein, each stage includes a target current level, such as a second peak current level 100 associated with the second intermediate stage (P2B). The time between the transition (indicated as reference numeral 98) from the first peak current level 96 to the second peak current level 100 may be limited by the difference between the target current levels. Therefore, the adjustment of one or two target current levels (e.g., the first peak current, the second peak current, the background current, etc.) can limit the duration of the transition between any two current levels. Additionally or alternatively, the ramp-down rates 98, 102 may correspond to one or more characteristics of the power source, characteristics of the cable, and / or may be adjustable by a user and / or a sequencer.

[0091] During the intermediate phase (P2A-B), the short circuit event progresses to a point in time when the molten ball transfer is about to occur. In order for the short circuit clearing to occur at a lower current level, the current level is reduced from the second peak current level 100 to a lower (e.g., background) current level 104. Again, the current decay rate (represented as 102) may be limited by various factors. Once the background current level 104 is reached, the short circuit clearing is completed at time t after the end phase P3. 5 The short circuit event is signaled to be complete. The cycle advances to the arc event phase until the cycle repeats. As shown, the voltage level increases 108 from a low level to a peak voltage level 110 sufficient to sustain an arc.

[0092] Figure 5 A graphical representation 120 of a current waveform 82 and a voltage waveform 84 during the stages of an arc event during a cyclic welding process as described herein is shown. As shown, the process is at time t 1 The short circuit event transitions to an arc event and at time t 5 The transition from an arc event to a short circuit event. Therefore, at voltage 122 and current 124, the process is close to the transition from the previous short circuit event to Figure 5As the electrode is retracted from the workpiece, the voltage rapidly increases (as indicated by reference numeral 126) to a second voltage level 128 as the arc is ignited. As shown, the voltage rises during the arc transition phase (AP1) as the short circuit event transitions to an arc event.

[0093] The commanded current level rises 130 to a first peak current level 132 associated with a first arc intermediate stage (AP2A). Additionally, a second arc intermediate stage (AP2B) may be included. As described herein, each stage includes a target current level, such as a first peak current level 132 and a second peak current level 134 associated with a second arc intermediate stage (AP2B). The time between transitions (indicated by reference numeral 136) from the first peak current level 132 to the second peak current level 134 may be limited by the difference between different target current levels. Thus, adjustment of one or two target current levels (e.g., a first peak current, a second peak current, a background current, etc.) may limit the duration of the transition between any two current levels. Additionally or alternatively, as disclosed herein, the ramp-down rate may correspond to one or more characteristics of the power source, characteristics of the cable, and / or may be adjusted by a user and / or a sequencer.

[0094] During the intermediate phase (P2A-B), the arc event progresses to a point in time when a short circuit is about to occur. Before entering the short circuit phase, the current level decreases from the second peak current level 134 to a lower (e.g., background) current level 138. Again, the current decay rate (represented as 140) may be limited by various factors. Once the background current level 138 is reached, the arc event is terminated at t 5 End, indicating that a short circuit event has been entered. The loop advances to the short circuit event phase until the loop repeats. As shown, the voltage level can respond to the command / target current level during the arc event phase and eventually decrease from the voltage level in the arc end phase AP3 (e.g., voltage 128 or the response voltage level) to a low voltage level (e.g., voltage 122) when a short circuit begins. Additionally or alternatively, similar to the end phase described with respect to the short circuit event, the duration of the arc end phase AP3 can be maintained at a level less than a predetermined value (e.g., 1 millisecond). As shown, Figure 5 The arc event includes a first arc intermediate stage (AP2A) and a second arc intermediate stage (AP2B). However, according to the present disclosure, a single intermediate stage, or three or more intermediate stages may be adopted.

[0095] Figure 6The method 600 of a welding power supply configured to generate output power for an arc welding process. In block 622, a controller (e.g., control circuit 22, 32) is configured to calculate representative durations of a plurality of arc events. For example, similar to a short circuit event, each arc event includes a transition phase, an intermediate phase, and an end phase. In block 624, one or more characteristics of the arc welding process are monitored (e.g., via one or more sensors 70).

[0096] In box 626, based on the data from the sensor, the controller calculates the duration of the transition phase of the arc event, the duration of the intermediate phase, and the sum of the duration of the ramp-down time from the target current of the intermediate phase to the target current of the end phase. In box 628, the controller compares the calculated sum of durations (and / or each individual phase duration) and compares the aforementioned sum to the representative duration (and / or the representative duration of each individual phase). If the aforementioned sum is not greater than the representative duration, the process returns to box 624 to continue monitoring the characteristics of the arc welding process.

[0097] If the aforementioned sum is greater than the representative duration, the process proceeds to block 630 where the controller adjusts the duration of one of the transition phase, the intermediate phase, or the ramp-down time so that the aforementioned sum is within the threshold range of the representative duration. As a result, the short circuit event is calculated to begin at a predetermined current level that is selected to control the timing and energy level associated with the short circuit clearing event.

[0098] The present method and system may be implemented in hardware, software and / or a combination of hardware and software.Example implementations include application specific integrated circuits and / or programmable control circuits.

[0099] As used herein, the terms "circuit" and "circuitry" refer to physical electronic components (i.e., hardware) and any software and / or firmware ("code") that can configure, be executed by, and / or otherwise be associated with hardware. As used herein, for example, a particular processor and memory may constitute a first "circuit" when executing a first line or more lines of code, and may constitute a second "circuit" when executing a second line or more lines of code. As used herein, "and / or" refers to any one or more items in a list that are combined together by "and / or". For example, "x and / or y" refers to any element in a three-element set {(x), (y), (x, y)}. In other words, "x and / or y" refers to "one or both of x and y". As another example, "x, y, and / or z" refers to any element in a seven-element set {(x), (y), (z), (x, y), (x, z), (y, z), (x, y, z)}. In other words, "x, y, and / or z" refers to "one or more of x, y, and z". As used herein, the term "exemplary" means serving as a non-limiting example, instance, or illustration. As used herein, the terms "such as" and "for example" provide a list of one or more non-limiting examples, instances, or illustrations. As used herein, a circuit system is "operable" to perform a function when the circuit system includes the necessary hardware and code (if necessary) to perform the function, regardless of whether the performance of the function is disabled or enabled (e.g., by a user-configurable setting, a factory adjustment, etc.).

[0100] Although the present method and / or system has been described with reference to certain embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the present method and / or system. For example, the frames and / or components of the disclosed examples may be combined, divided, rearranged and / or otherwise modified. In addition, many modifications may be made to adapt specific circumstances or materials to the teachings of the present disclosure without departing from the scope of the present disclosure. Therefore, the present method and / or system is not limited to the specific embodiments disclosed. On the contrary, the present method and / or system will include all embodiments that fall within the scope of the appended claims, both literally and under the doctrine of equivalents.

Claims

1. A welding type system, include: a welding-type power supply configured to generate output power for an arc welding process; as well as A controller configured to: Calculating representative durations of a plurality of short circuit events during the arc welding process, wherein each short circuit event transitions from an arc event, and each short circuit event includes: a transition phase, the transition phase including a voltage drop from a peak voltage level to a first low voltage level corresponding to the short circuit, an intermediate phase after the transition phase, the intermediate phase initiated by a current increase from a first background current level to a target current level and a voltage increase to an intermediate voltage level, the intermediate voltage level being lower than the peak voltage level, an end phase after the intermediate phase, the end phase including a voltage drop to a second low voltage level, a current drop to a second background current level, and maintaining the second background current level and increasing the voltage before switching to another arc event; calculating a sum of a duration of the transition phase, a duration of the intermediate phase, and a duration of a ramp-down time during the ending phase from the target current level of the intermediate phase to the second background current level of the ending phase associated with a given short circuit event; selecting a predetermined value for the duration of the end phase; and The welding-type power supply is controlled so as to adjust one of the durations of the transition phase, the intermediate phase, or the ramp-down time associated with the given short circuit event so that the sum is within a threshold range of the representative duration and so as to maintain the duration of the end phase less than the predetermined value.

2. The system according to claim 1, in, The controller is configured to receive a signal from a sensor, the signal representing a characteristic of each of the plurality of short circuit events during the arc welding process.

3. The system according to claim 2, in, The characteristic includes at least one of current, duration, or voltage.

4. The system according to claim 3, in, The controller is configured to measure a duration of the ending phase of the given short circuit event based on one or more of the characteristics.

5. The system of claim 2, further comprising a welding-type torch for performing the arc welding process, the welding-type torch comprising a wire feeder configured to drive an electrode to a workpiece via the welding-type torch.

6. The system according to claim 5, in, The wire feeder is configured to control advancement or retraction of the electrode.

7. The system of claim 1, in, The controller is configured to adjust a duration of the termination phase such that a short circuit clearing event associated with the given short circuit event occurs at a target current of the termination phase.

8. The system of claim 1, in, The target current in the middle stage is greater than the target current in the end stage.

9. The system of claim 1, in, The controller is configured to adjust one of the target current of the intermediate stage or the target current of the end stage to reduce the ramp-down time.

10. The system of claim 1, in, The controller is configured to adjust a duration of two or more of the transition phase, the intermediate phase, and the ramp-down time associated with the given short circuit event.

11. The system of claim 1, in, The welding-type power supply includes a switch mode power supply.

12. The system according to claim 11, in, The ramp-down rate is limited by the voltage amplitude associated with the output power from the switch-mode power supply for the arc welding process.

13. The system of claim 1, in, Each short circuit event includes at least two intermediate stages, each intermediate stage including a respective target current level.

14. A welding type system, include: a welding-type power supply configured to generate output power for an arc welding process; a welding torch including a wire feeder configured to drive an electrode forward or retract during the arc welding process; as well as A controller configured to: Calculating representative durations of a plurality of short circuit events during the arc welding process, wherein each short circuit event comprises: a transition phase starting from the arc event, the transition phase comprising a voltage drop from a first voltage level to a second voltage level corresponding to the short circuit, a first intermediate phase after the transition phase, the first intermediate phase being initiated by a current rising from a first background current level to a first target current level and a voltage rising to a third voltage level lower than the first voltage level, a second intermediate phase after the first intermediate phase, the second intermediate phase comprising a current drop to a second target current level lower than the first target current level and a voltage drop to a fourth voltage level lower than the third voltage level, an end phase after the second intermediate phase, the end phase comprising a first portion and a second portion, the first portion comprising a current drop from the second target current level of the second intermediate phase to a second background current level, the second portion comprising maintaining the second background current level before switching to another arc event; calculating a sum of a duration of the transition phase, a duration of the intermediate phase, and a duration of a ramp-down time during the ending phase from the second target current level of the second intermediate phase to the second background current level of the ending phase associated with a given short circuit event; When the electrode is advanced or retracted during the transition phase, the intermediate phase, or the end phase, adjusting the wire feed speed of the electrode to increase the time of the short circuit event so that the sum is within the threshold range of the representative duration; and A total duration of a first duration of the first portion of the end phase and a second duration of the second portion of the end phase is maintained to be less than a predetermined value.

15. The system according to claim 14, wherein, the controller is configured to increase the acceleration when the electrode retracts during the transition phase, the intermediate phase, or the end phase associated with the given short - circuit event.

16. The system according to claim 14, wherein, the controller is configured to decrease the acceleration when the electrode advances during the arc event associated with the given short - circuit event.

17. The system according to claim 16, wherein, the controller is configured to adjust the length of the electrode extending from the torch during the arc event to control the arc length.

18. A welding - type system, comprising: a welding - type power supply configured to generate output power for an arc - welding process; a torch including a wire feeder configured to drive an electrode to advance or retract during the arc - welding process; and a controller configured to: calculate a representative duration of a plurality of arc events during the arc - welding process, wherein each short - circuit event includes a transition phase starting from the arc event, an intermediate phase after the transition phase, and an end phase after the intermediate phase, the transition phase includes a voltage drop corresponding to the short - circuit, the intermediate phase includes a current rising from a background current level to a target current level, the end phase includes a first part and a second part, the first part includes a current dropping from the target current level of the intermediate phase to the background current level, and the second part includes maintaining the background current level before transitioning to another arc event; calculate the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the slope - down time during the end phase from the target current level of the intermediate phase to the background current level associated with a given short - circuit event; when the electrode advances or retracts during the transition phase, the intermediate phase, or the end phase, adjust the wire - feeding speed of the electrode to increase the time of the short - circuit event such that the sum is within a threshold range of the representative duration; and wherein the controller is further configured to maintain the total duration of a first duration of the first part of the end phase and a second duration of the second part of the end phase to be less than a predetermined value.

19. A welding - type system, comprising: a welding - type power supply configured to generate output power for an arc - welding process; and a controller configured to: calculate a representative duration of a plurality of arc events during the arc - welding process, wherein each arc event includes: a transition phase including a voltage rising from a first voltage level to a second voltage level and a current reaching a first background current level; a first intermediate stage after the transition stage, the first intermediate stage comprising a current rising from the first background current level to a first peak current, and a voltage rising from the second voltage level to a third voltage level; a second intermediate stage after the first intermediate stage, the second intermediate stage comprising a current drop to a second peak current and a voltage drop to a fourth voltage level; and an end phase after the second intermediate phase, after which a short circuit occurs, the end phase comprising a voltage drop to a fifth voltage level and a current drop to a second background current level; calculating the sum of the duration of the transition phase, the duration of the first intermediate phase and the duration of the second intermediate phase of a given arc event, and the duration of the ramp-down time from the second peak current of the second intermediate phase to the second background current level of the ending phase during the ending phase, and maintaining the second background current level of the ending phase when the arc welding process transitions to a short circuit event; adjusting a duration of one of the transition phase, the first intermediate phase, the second intermediate phase, or the ramp-down time associated with the given arc event so that the sum is within a threshold range of the representative duration; and The duration of the end phase is maintained to be less than a predetermined value.

20. The system of claim 19, in, The welding-type power supply includes a switch mode power supply to generate output power.

21. The system of claim 19, in, The controller is configured to adjust a target current of the intermediate phase associated with the given arc event.

22. A welding system, include: a welding-type power supply configured to generate output power for an arc welding process; a welding torch including a wire feeder configured to drive an electrode forward or retract during the arc welding process; as well as A controller configured to: Calculating representative durations of a plurality of arc events during the arc welding process, wherein each arc event comprises: a transition phase, wherein the voltage rises from a first voltage level to a second voltage level, and the current reaches a background current level; an intermediate stage after the transition stage, the intermediate stage comprising a current rising from the background current level to a peak current, and a voltage rising from the second voltage level to a third voltage level; an end stage after the intermediate stage, after which a short circuit occurs, the end stage comprising a voltage drop to the second voltage level and a current drop to the background current level; calculating a sum of a duration of the transition phase, a duration of the intermediate phase, and a duration of a ramp-down time during the ending phase from the peak current of the intermediate phase to the background current level of the ending phase for a given arc event; When the electrode is advanced or retracted during the transition phase, the intermediate phase, or the end phase, adjusting the wire feed speed of the electrode to adjust the timing of the arc event so that the sum is within a threshold range of the representative duration; and The duration of the end phase is maintained to be less than a predetermined value.

23. A welding system, include: a welding-type power supply configured to generate output power for an arc welding process; as well as A controller, the controller being configured to: Calculating representative durations of a plurality of arc events during an arc welding process, wherein each arc event comprises: a transition phase, wherein the transition phase includes the voltage rising from the first voltage level to the second voltage level, and the current reaching the background current level; an intermediate stage after the transition stage, the intermediate stage including a current rising from the background current level to a peak current, and a voltage rising from the second voltage level to a third voltage level; and an end phase after the intermediate phase, the end phase being followed by a short circuit, the end phase comprising a voltage drop to the second voltage level and a current drop to the background current level; calculating the sum of the duration of the transition phase, the duration of the intermediate phase, and the duration of the ramp-down time from the peak current in the intermediate phase to the background current level in the ending phase during the ending phase for a given arc event, wherein the background current level in the ending phase is maintained when the arc welding process transitions to a short circuit event; adjusting a duration of one of the transition phase, the intermediate phase, or the ramp-down time associated with the given arc event so that the sum is within a threshold range of the representative duration; and The duration of the end phase is maintained to be less than a predetermined value.

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