A welding power source and control method thereof, short-circuit transition welding method and device

Abstract

The present application discloses a welding power source and a control method thereof, a short-circuit transition welding method and a device, wherein the control method of the welding power source includes: obtaining characteristic parameters of an electrical signal between a welding wire and a base material; wherein the electrical signal includes a current signal and a voltage signal; determining the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal; in response to the molten droplet short-circuit transition cycle entering the initial arcing stage, adjusting the current signal from positive to negative; adjusting the average voltage of the voltage signal in the molten droplet short-circuit transition cycle to within a constant threshold range. In the above manner, the control method of the welding power source in the present application effectively reduces the overall welding heat input during the welding process by realizing the polarity conversion of the current signal in a molten droplet short-circuit transition cycle, thereby reducing ineffective power consumption and reducing the risk of welding defects such as "bite"; and at the same time, it also effectively improves the stability of the arc.

Description

Technical Field

[0001] The present application relates to the technical field of protective welding, and in particular to a welding power source and a control method thereof, and a short-circuit transition welding method and device. Background Art

[0002] In the melting electrode gas shielded welding, a fusible welding wire is generally used as the electrode of the welding power source to contact the base material, that is, the workpiece to be welded, to form a circuit, and to generate an arc starting current, so as to ignite an arc between the continuously fed welding wire and the base material as a heat source to melt the welding wire and the base metal, thereby achieving welding of the base material. Among them, the welding power source provides energy for the electric welding device, controls the generation and extinction of the arc, and then controls the welding process. And the output current of the welding power source will directly affect the stability of the welding process and the welding quality.

[0003] However, current welding power supply control methods generally have problems such as excessive welding heat input and poor arc stability, resulting in a narrow scope of application. Summary of the invention

[0004] The main technical problem solved by the present application is to provide a welding power supply and its control method, a short-circuit transition welding method and device, which can solve the problems of excessive welding heat input, poor arc stability and narrow application range commonly found in the control methods of welding power supplies in the prior art.

[0005] In order to solve the above technical problems, a technical solution adopted in the present application is: to provide a control method for a welding power supply, wherein the control method for the welding power supply includes: obtaining characteristic parameters of the electrical signal between the welding wire and the base material; wherein the electrical signal includes a current signal and a voltage signal; determining the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal; in response to the molten droplet short-circuit transition cycle entering the initial stage of arcing, adjusting the current signal from positive to negative; and adjusting the average voltage of the voltage signal in the molten droplet short-circuit transition cycle to within a constant threshold range.

[0006] Among them, the characteristic parameters of the electrical signal also include the rising speed of the voltage signal. The steps of determining the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal include: detecting whether the rising speed exceeds a first set threshold value; in response to the rising speed exceeding the first set threshold value, determining that the molten droplet short-circuit transition cycle has entered the initial stage of arcing.

[0007] The step of adjusting the current signal from positive to negative includes: adjusting the current signal from a positive first current value to a negative first current value using a first change speed, and maintaining the negative first current value until the end of the initial arcing stage.

[0008] Among them, in response to the molten droplet short-circuit transition cycle entering the initial stage of arcing, after the step of adjusting the current signal from positive to negative, and before the step of adjusting the average voltage of the voltage signal in the molten droplet short-circuit transition cycle to within a constant threshold range, it also includes: after the initial stage of arcing lasts for a first period of time, determining that the molten droplet short-circuit transition cycle enters the late stage of arcing, using a second change speed to adjust the current signal from a negative first current value to 0; using a third change speed to adjust the current signal from 0 to a positive second current value; or, using a third change speed to adjust the current signal for a second period of time.

[0009] Among them, the step of adjusting the average voltage of the voltage signal in the molten droplet short circuit transition period to within a constant threshold range includes: adjusting the current signal to a set pulse signal, and making the average voltage of the voltage signal in the molten droplet short circuit transition period within a constant threshold range.

[0010] Among them, the control method of the welding power supply also includes: in response to the molten droplet short-circuit transition period entering the initial short-circuit stage, adjusting the current signal to a third current value; after the third current value is maintained for a third period of time, using a fourth change speed to adjust the increase current signal.

[0011] Among them, after the step of maintaining the third current value for a third period of time and then using a fourth change speed to adjust the current signal to increase, it also includes: after maintaining the third current value for a fourth period of time and then using a fifth change speed to adjust the current signal to increase; wherein the fifth change speed is less than the fourth change speed.

[0012] Among them, the characteristic parameters of the electrical signal also include the falling speed and / or falling amplitude of the voltage signal. The steps of determining the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal include: detecting whether the falling speed and / or falling amplitude exceeds a second set threshold value; in response to the falling speed and / or falling amplitude exceeding the second set threshold value, determining that the molten droplet short-circuit transition cycle has entered the initial short-circuit stage.

[0013] The control method of the welding power supply further includes: in response to the molten droplet short-circuit transition period entering the molten droplet necking stage, adjusting the current signal to a first positive current value.

[0014] Among them, the characteristic parameters of the electrical signal also include instantaneous power and / or instantaneous power change rate. The steps of determining the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal include: detecting whether the instantaneous power and / or the instantaneous power change rate exceeds a third set threshold; in response to the instantaneous power and / or the instantaneous power change rate exceeding the third set threshold, determining that the molten droplet short-circuit transition cycle enters the molten droplet necking stage.

[0015] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a short-circuit transition welding method, wherein the short-circuit transition welding method includes: outputting an electrical signal to the welding wire and the base material; wherein the electrical signal includes a current signal and a voltage signal; and adjusting the electrical signal by using the control method of the welding power supply as described in any one of claims 1 to 10, so as to utilize the electrical signal to melt the welding wire and weld the base material.

[0016] Among them, the short-circuit transition welding method also includes: driving the welding wire to move towards or away from the base material according to the current stage of the molten droplet short-circuit transition cycle, and controlling the average speed of the welding wire during the molten droplet short-circuit transition cycle within a set speed threshold.

[0017] Among them, the steps of driving the welding wire to move towards or away from the base material according to the current stage of the molten droplet short-circuit transition cycle, and controlling the average speed of the welding wire during the molten droplet short-circuit transition cycle within a set speed threshold include: driving the welding wire to move towards the base material at a first movement speed in the initial stage of arcing and the later stage of arcing; driving the welding wire to move away from the base material at a second movement speed in the initial stage of short circuit and the molten droplet necking stage, and controlling the average speed of the welding wire during the molten droplet short-circuit transition cycle within the set speed threshold.

[0018] Among them, the welding power supply also includes a filtering circuit, which couples the sampling circuit and the main control circuit. The filtering circuit receives the electrical signal sent by the sampling circuit, filters the electrical signal and sends it to the main control circuit, so that the main control circuit uses the filtered electrical signal to adjust the electrical signal using the control method of the welding power supply as described in any one of claims 1-10.

[0019] In order to solve the above technical problems, another technical solution adopted in the present application is: to provide a short-circuit transition welding device, wherein the short-circuit transition welding device includes a welding power supply and a welding wire, and the welding power supply connects the welding wire and an external base material; wherein the welding power supply is used to output an electrical signal to the welding wire and the base material, and the electrical signal is adjusted by using the control method of the welding power supply as described in any one of claims 1-10, so as to utilize the electrical signal to melt the welding wire and weld the base material.

[0020] Among them, the short-circuit transition welding device also includes a driving mechanism, which is connected to the welding power supply and the welding wire. The driving mechanism receives a driving control signal sent by the welding power supply according to the current stage of the molten droplet short-circuit transition cycle, so as to drive the welding wire to move in a first movement speed toward the direction approaching the base material, or to move in a second movement speed toward the direction away from the base material based on the driving control signal.

[0021] The beneficial effects of the present application are as follows: Different from the prior art, the control method of the welding power supply provided by the present application obtains the characteristic parameters of the electrical signal between the welding wire and the base material, and determines the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal. When the molten droplet short-circuit transition cycle enters the initial stage of arcing, the current signal is adjusted from positive to negative, and the average voltage of the voltage signal in the molten droplet short-circuit transition cycle is adjusted to a constant threshold range, so as to realize the polarity change of the current signal in one molten droplet short-circuit transition cycle, thereby effectively reducing the overall welding heat input during the welding process, thereby reducing ineffective power consumption and reducing the risk of welding defects such as "bite edge"; and by adopting constant voltage regulation in the later stage of arcing, the self-regulation ability of the arc is effectively guaranteed, thereby effectively improving the stability of the arc, as well as the good and consistent welding quality, and making the application range of the welding power supply control method wider. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work, among which:

[0023] Figure 1 It is a flow chart of a first embodiment of a control method for a welding power source of the present application;

[0024] Figure 2 It is a structural schematic diagram of an implementation method of the short-circuit transition welding device of the present application;

[0025] Figure 3 It is a flow chart of a second embodiment of the control method of a welding power source of the present application;

[0026] Figure 4 It is a flow chart of a third embodiment of the control method of a welding power source of the present application;

[0027] Figure 5 It is a flow chart of a fourth embodiment of the control method of a welding power source of the present application;

[0028] Figure 6 yes Figure 5 A schematic diagram of waveforms of an embodiment of current and voltage signals corresponding to S41-S415;

[0029] Figure 7 It is a schematic diagram of the process of the first implementation method of the short-circuit transition welding method of the present application;

[0030] Figure 8It is a flow chart of the second implementation mode of the short-circuit transition welding method of the present application;

[0031] Fig. 9 yes Figure 8 A schematic diagram of a flow chart of an embodiment of S63;

[0032] Fig.10 yes Fig. 9 A schematic diagram of waveforms of current, voltage signals and wire feeding speed corresponding to S631-S632 in an embodiment;

[0033] Fig.11 It is a structural schematic diagram of the first embodiment of the welding power supply of the present application;

[0034] Fig.12 It is a structural schematic diagram of the second embodiment of the welding power supply of the present application. DETAILED DESCRIPTION

[0035] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0036] The terms "first", "second" and "third" in this application are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Thus, the features defined as "first", "second" and "third" can explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. All directional indications (such as up, down, left, right, front, back...) in the implementation mode of this application are only used to explain the relative position relationship, movement, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices.

[0037] Reference to "embodiment" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiment may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] The present application is described in detail below with reference to the accompanying drawings and implementation methods.

[0039] See also Figure 1 and Figure 2 ,in, Figure 1 is a flow chart of a first embodiment of a control method for a welding power source of the present application, Figure 2 This is a schematic diagram of the structure of an embodiment of the short-circuit transition welding device of the present application. Specifically, it may include the following steps:

[0040] S11: Acquire characteristic parameters of the electrical signal between the welding wire and the base material.

[0041] It is understandable that if Figure 2 As shown, the welding power source 101 in this embodiment is specifically a power source for providing arc starting current to the welding wire 102 and the base material 201, that is, the workpiece to be welded, in the short-circuit transition welding device 100, so as to melt the welding wire 102, maintain the arc 301, and heat the base material 201, thereby realizing welding of the base material 201. The control method of the welding power source 101 is to control the generation and extinction of the arc 301 between the welding wire 102 and the base material 201 by controlling the output of the electrical signal of the welding power source 101, thereby realizing control of the entire welding process.

[0042] It is worth noting that gas shielded arc welding with a consumable electrode, referred to as gas shielded arc welding, gas shielded welding, also known as consumable electrode inert gas shielded arc welding and consumable electrode active gas shielded arc welding, specifically refers to an arc welding that uses an external gas as an arc medium and protects the arc 301 and the welding area, and is an automatic or semi-automatic process, wherein automatic welding requires continuous feeding of welding wire 102, and argon or helium is fed into the nozzle of the welding torch for protection. The welding power source 101 can use direct current and alternating current. According to the arc 301, it can be divided into spherical arc, jet arc 301, pulse jet arc 301 and short-circuit arc welding.

[0043] When welding is required, the welding power source 101 is first used to provide power to each device, and the user sets various parameters of the welding device, such as gas, material of welding wire 102, welding voltage and welding current, etc. Then the user presses the welding gun switch, and the welding power source 101 enters the arc ignition stage. The arc 301 melts the welding wire 102 and the base material 201 to form a molten pool and a welding area, which can effectively prevent the harmful effects of the surrounding air under the protection of inert gas or active gas, and then the welding is completed through the process of droplet transfer. Droplet transfer refers to the whole process in which the molten metal at the end of the welding wire 102 or the welding rod forms a droplet under the heat of the arc 301, and is separated from the end of the welding wire 102 and transferred to the molten pool under the action of various forces. It is directly related to the stability of the welding process, weld formation, spatter size, etc., and ultimately affects the welding quality and production efficiency.

[0044] Among them, for gas shielded welding, one form of droplet transfer is short-circuit transfer, which means that when welding with a relatively small current and low voltage, the droplet directly contacts the molten pool before it leaves the end of the welding wire 102, the arc 301 is extinguished instantly and short-circuited, and the droplet transfers to the molten pool under the electromagnetic contraction force generated by the short-circuit current and the surface tension of the liquid metal; short-circuit transfer is a kind of free transfer, the droplet flies freely through the space of the arc 301, and there is no direct contact between the end of the welding wire 102 and the molten pool; after the droplet falls off, the arc 301 is re-ignited, and the transfer is carried out alternately; and short-circuit transfer is the alternation of arcing and arc extinguishing. During short-circuit transfer, the average welding current is small.

[0045] Droplet transfer refers to the whole process that the molten metal at the end of the welding wire 102 or the welding rod forms a droplet under the heat of the arc 301, and is separated from the end of the welding wire 102 by various forces and transfers to the molten pool. It is directly related to the stability of the welding process, weld formation, spatter size, etc., and ultimately affects the welding quality and production efficiency.

[0046] For gas shielded welding, due to the short-circuit transition of metal droplets, the load state often switches between arcing and short-circuiting. In addition, the transition process from arcing to short-circuiting and from short-circuiting to arcing causes instantaneous changes in output current and voltage, which have a significant impact on welding spatter and weld formation. The reason why welding spatter is directly affected by the dynamic characteristics of the power supply is that the height of the short-circuit current peak and the speed of the growth rate are directly affected by the dynamic response speed of the welding machine.

[0047] If the dynamic response is too fast, the short-circuit current peak value will be too high and the growth rate will be too fast, causing explosion and splashing before the short-circuit liquid bridge is formed, and the short-circuit transition form cannot be formed. The characteristics of this splashing are high frequency and small particles. If the dynamic response is too slow, the short-circuit current growth rate is slow and the peak value is small. The magnetic contraction force produced by the current is not enough to ensure the smooth transition of the short-circuit liquid bridge. The short-circuit transition time is long, and the splashing characteristics produced are: low frequency and coarse particles.

[0048] Therefore, the welding power source 101 is required to have an appropriate short-circuit current growth rate to avoid large spatter. The short-circuit current has little effect on the heating of the weld joint, the penetration and formation of the weld. The main factor affecting the penetration and formation of the weld is the arc energy, that is, the arc current and voltage.

[0049] Since there is a short circuit process during welding, the power supply voltage cannot be too high, and the arc current in the steady state is small, so the current change process after the short circuit is an important part of the arc capacity. In other words, the dynamic characteristics of the welding power supply 101 have an important influence on the weld formation and penetration. The slower the dynamic characteristics, the longer the current transition time after the short circuit is over, the greater the arc capacity provided, the better the weld formation, and the greater the penetration. However, too slow dynamic characteristics will make the current growth rate too slow, resulting in serious spatter and even destroying the stability of the arc 301. Therefore, it is necessary to properly and accurately control the welding power supply 101 to ensure the requirements of the welding process and the stability of the welding process.

[0050] In this embodiment, the welding power source 101 specifically utilizes an internal sampling circuit to obtain characteristic parameters of the electrical signal between the welding wire 102 and the base material 201 in real time, which can also be understood as characteristic parameters of the arc 301 .

[0051] Among them, the electrical signal specifically includes the current signal and the voltage signal between the welding wire 102 and the base material 201; and the characteristic parameters of the electrical signal can specifically correspond to one or more of any reasonable parameters including the current value of the current signal, the voltage value of the voltage signal, the change speed of the current signal and / or the voltage signal, the instantaneous power of the electrical signal and / or the instantaneous power change rate, etc., and the present application does not limit this.

[0052] S12: Determine the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal.

[0053] Furthermore, since the transition process from arcing to short circuit and from short circuit to arcing will cause instantaneous changes in the electrical signal during the entire welding process, the welding power supply 101 can determine the current stage of the molten droplet short-circuit transition period between the welding wire 102 and the base material 201 based on the characteristic parameters of the currently acquired electrical signal. For example, by detecting whether the rising speed of the voltage signal exceeds the first set threshold, it is determined that the molten droplet short-circuit transition period enters the initial arcing stage; by detecting whether the falling speed and / or falling amplitude of the voltage signal exceeds the second set threshold, it is determined that the molten droplet short-circuit transition period enters the initial short-circuit stage, etc.

[0054] It is worth mentioning that the molten droplet short-circuit transition cycle can generally be divided into the initial short-circuit stage, the molten droplet necking stage, the initial arcing stage and the late arcing stage, and they are gradually alternating in time sequence. That is, in the welding process, it usually goes through multiple molten droplet short-circuit transition cycles, and specifically enters the initial short-circuit stage, the molten droplet necking stage, the initial arcing stage and the late arcing stage in a time sequence cycle.

[0055] The switching transition between each two adjacent stages will cause an instantaneous change in the electrical signal, which will be sampled and acquired by the welding power supply 101, and then its signal output will be adjusted to achieve a better welding effect.

[0056] S13: In response to the droplet short-circuit transition period entering the initial arcing stage, the current signal is adjusted from positive to negative.

[0057] Furthermore, when the welding power supply 101 determines that the current droplet short-circuit transition cycle has entered the initial arcing stage, the current signal is adjusted from positive to negative.

[0058] It is worth noting that when the welding power source 101 adopts positive power supply, more electric energy will be used to heat the molten pool, that is, to heat the base material 201, and a small part of the electric energy will be used to melt the welding wire 102; when the welding power source 101 adopts negative power supply, more electric energy will be used to melt the welding wire 102, and a small part of the electric energy will be used to heat the molten pool. Therefore, by controlling the proportion of the positive power supply and the negative power supply of the welding power source 101, the proportion of electric energy allocated to the welding wire 102 and the molten pool can be adjusted. When the negative power supply time is zero, the power source degenerates into a traditional single-polarity melting electrode gas shielded welding system, at which time the molten pool is heated the most and the welding wire 102 is heated the least.

[0059] It can be understood that by realizing the polarity switching of the current signal within each droplet short-circuit transition cycle, the efficiency of adjusting the distribution of electric energy between the welding wire 102 and the molten pool by adjusting the duration of the negative current is effectively retained, thereby effectively ensuring good and consistent welding quality without affecting the droplet transition and droplet size, without affecting the stability of the arc 301, and reducing the heat input of welding.

[0060] It is worth noting that the heat input of welding refers to the heat energy input to the weld per unit length by the welding energy during fusion welding.

[0061] S14: adjusting the average voltage of the voltage signal during the droplet short-circuit transition period to within a constant threshold range.

[0062] Specifically, a constant voltage control algorithm is used to adjust the average voltage of the voltage signal in a complete droplet short-circuit transition cycle to a constant threshold range to ensure that the average voltage in the arc maintenance stage is constant, and at the same time, the average voltage in the complete cycle is constant, thereby retaining the self-regulating effect of the arc 301 to avoid problems such as loss of control of the arc 301 length and decreased wettability of the molten pool caused by controlling the droplet size; and through average voltage control, the overall voltage is guaranteed to be constant, that is, from a macroscopic point of view, the average length of the arc 301 is constant, thereby ensuring the consistency of welding and the uniformity of the weld.

[0063] The above scheme, by realizing the polarity change of the current signal in a molten droplet short-circuit transition period, effectively reduces the overall welding heat input during the welding process, thereby reducing ineffective power consumption and reducing the risk of welding defects such as "bite edge"; and by adopting constant voltage regulation in the later stage of arcing, it also effectively guarantees the self-regulation ability of the arc 301, thereby effectively improving the stability of the arc 301, as well as the good and consistent welding quality, and making the application range of the welding power supply 101 control method wider.

[0064] Furthermore, in one embodiment, the characteristic parameter of the electrical signal also includes the rising speed of the voltage signal. In the above S12, it specifically includes: detecting whether the rising speed exceeds a first set threshold value; in response to the rising speed exceeding the first set threshold value, determining that the molten droplet short-circuit transition period enters the initial stage of arcing.

[0065] It can be understood that when the molten droplet short-circuit transition cycle enters the initial stage of arcing, the conductive state between the welding wire 102 and the base material 201 will quickly switch from a short circuit to an open circuit state, so that the voltage signal between the welding wire 102 and the base material 201 will increase rapidly, thereby being able to use the detection of the rising speed of the voltage signal to determine whether the current state has entered the initial stage of arcing.

[0066] Among them, the first set threshold can be reasonably set according to the signal sampling, analysis and statistics in the actual welding scene, so that when it is determined that the rising speed of the voltage signal exceeds the second set threshold, it can be determined that the molten droplet short-circuit transition cycle enters the initial stage of arcing. This application does not limit this.

[0067] Furthermore, in one embodiment, in the above S13, it specifically includes: adjusting the current signal from a positive first current value to a negative first current value using a first change speed, and maintaining the negative first current value until the end of the initial arcing stage.

[0068] It can be understood that when the welding power supply 101 determines that the molten droplet short-circuit transition cycle has entered the initial arcing stage, it specifically uses a first change speed to adjust the current signal from a positive first current value to a negative first current value, and maintains the negative first current value until the end of the initial arcing stage, so as to utilize the negative current in the initial arcing stage and its duration to reduce the heat input of welding as much as possible.

[0069] Optionally, the first change speed may be 500-1000A / ms (ampere / millisecond), that is, in the initial stage of arcing, the current signal is adjusted from the positive first current value to the negative first current value at a speed of decreasing by 500-1000A (ampere) per millisecond.

[0070] Optionally, the first current value may be specifically 20-200A, which is not limited in the present application.

[0071] Furthermore, in one embodiment, the above S14 specifically also includes: adjusting the current signal to a set pulse signal, and making the average voltage of the voltage signal in the droplet short-circuit transition period be within a constant threshold range.

[0072] It is understandable that in order to further improve the weld formation, a method of alternating control of positive pulse current and negative pulse current can be specifically adopted in the arc burning stage. For example, after the current signal is adjusted from positive to negative in the initial stage of arc burning, the current signal is adjusted to a set pulse signal, and at the same time, a constant voltage regulation algorithm is used to adjust the average voltage of the voltage signal in a molten droplet short-circuit transition cycle to a constant threshold range until the end of the late stage of arc burning.

[0073] The positive and negative pulse widths of the set pulse signal are small, i.e., "narrow pulse widths", which are used to control the energy of the droplet, i.e., the energy of the droplet is supplied in a digital manner. By controlling the current rising and falling slopes when the positive and negative narrow pulse widths are switched, the arc 301 stiffness can be indirectly controlled and the welding stability can be improved.

[0074] The positive and negative adjustment of "narrow pulse width" can more accurately control the energy of droplet formation, thereby effectively controlling the droplet size; at the same time, the adjustment control of the change speed when switching between positive and negative pulses can effectively improve the arc 301 stiffness and welding stability.

[0075] Optionally, the constant threshold may be specifically 10-50V (volts), which is not limited in the present application.

[0076] Furthermore, in one embodiment, the characteristic parameters of the electrical signal also include the falling speed and / or falling amplitude of the voltage signal. In the above S12, it specifically also includes: detecting whether the falling speed and / or falling amplitude exceeds a second set threshold value; in response to the falling speed and / or falling amplitude exceeding the second set threshold value, determining that the molten droplet short-circuit transition cycle enters the initial stage of short circuit.

[0077] It can be understood that when the arcing late stage in one molten droplet short-circuit transition cycle enters the short-circuit initial stage of another molten droplet short-circuit transition cycle, the conductive state between the welding wire 102 and the base material 201 will quickly switch from mutual disconnection to a short-circuit state, so that the voltage signal between the welding wire 102 and the base material 201 drops rapidly, thereby being able to use the detection of the falling speed and / or falling amplitude of the voltage signal to judge whether the current state has entered the short-circuit initial stage.

[0078] Among them, the second set threshold can be reasonably set according to the signal sampling, analysis and statistics in the actual welding scene, so that when it is determined that the falling speed and / or the falling amplitude of the voltage signal exceeds the second set threshold, it can be determined that the molten droplet short-circuit transition period enters the initial stage of short circuit. This application does not limit this.

[0079] Further, in one embodiment, in the above S12, it specifically includes: in response to the droplet short-circuit transition period entering the droplet necking stage, adjusting the current signal to a first positive current value.

[0080] Optionally, the first current value may be specifically 20-200A, which is not limited in the present application.

[0081] Optionally, the duration of the droplet necking stage does not exceed 2 ms (milliseconds), which is not limited in the present application.

[0082] Furthermore, in one embodiment, the characteristic parameters of the electrical signal also include instantaneous power and / or instantaneous power change rate. In the above S12, it specifically also includes: detecting whether the instantaneous power and / or instantaneous power change rate exceeds a third set threshold; in response to the instantaneous power and / or instantaneous power change rate exceeding the third set threshold, determining that the molten droplet short-circuit transition period enters the molten droplet necking stage.

[0083] It is worth explaining that the molten droplet necking stage specifically refers to the stage when the end of the welding wire 102 melts and separates from the main body of the welding wire 102 to transition from a short circuit between the welding wire 102 and the base material 201 to the re-ignition of the welding wire 102. During this stage, the instantaneous power and the instantaneous power change rate of welding will exceed a certain critical value, so that the critical value can be utilized, that is, the detection of whether the instantaneous power and / or the instantaneous power change rate exceeds the third set threshold value to determine whether the molten droplet short-circuit transition cycle has entered the molten droplet necking stage.

[0084] See also Figure 3 , Figure 3 : is a flow chart of a second embodiment of the control method of the welding power supply of the present application. The control method of the welding power supply of this embodiment is Figure 1 A flow chart of a detailed implementation of the control method of the welding power source in the embodiment of the present invention specifically includes the following steps:

[0085] S21: Acquire characteristic parameters of the electrical signal between the welding wire and the base material.

[0086] S22: Determine the current stage of the droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal.

[0087] S23: In response to the droplet short-circuit transition period entering the initial arcing stage, the current signal is adjusted from positive to negative.

[0088] Among them, S21, S22 and S23 are Figure 1 S11, S12 and S13 are the same, please refer to S11, S12 and S13 and their related text descriptions for details, which will not be repeated here.

[0089] S24: After the initial arcing stage lasts for a first time period, it is determined that the droplet short-circuit transition period enters the later arcing stage, and the current signal is adjusted from the negative first current value to 0 using a second change speed.

[0090] It is understandable that the welding power supply 101 specifically determines whether the molten droplet short-circuit transition cycle enters the late arcing stage based on the current duration of the initial arcing stage, so that when entering the late arcing stage, the current signal is adjusted from the negative first current value to 0 using a second change speed.

[0091] The second change speed may specifically be the adjustment limit of the hardware performance of the welding power source 101 itself, and the current signal is adjusted from the negative first current value to 0 at the fastest change speed.

[0092] Optionally, the first duration may be specifically 0-2 ms, which is not limited in this application.

[0093] S25: Use a third change speed to adjust the current signal from 0 to a second positive current value.

[0094] Optionally, the third change speed may specifically be 500-1000A / ms, which is not limited in the present application.

[0095] Optionally, the second current value is 30-300A, which is not limited in the present application.

[0096] S26: Adjusting the average voltage of the voltage signal during the droplet short-circuit transition period to within a constant threshold range.

[0097] Among them, S26 and Figure 1 For details, please refer to S14 and its related text descriptions, which will not be repeated here.

[0098] Furthermore, in one embodiment, the above S25 may be specifically replaced by: adjusting the current signal at a third changing speed for a second time period.

[0099] It is understandable that the welding power supply 101 can also specifically use a third change speed to adjust the current signal, and switch to constant voltage regulation after a second period of time, so as to adjust the average voltage of the voltage signal in the droplet short-circuit transition period to a constant threshold range.

[0100] In another embodiment, the welding power supply 101 can also specifically use a third change speed to adjust the current signal for a second period of time to adjust the current signal to a second positive current value, which can be specifically 30-300A. That is, when the current signal is adjusted for the second period of time and the current signal does not exceed 30A, the current current signal is set to 30A; when the current signal is adjusted for the second period of time and the current signal exceeds 300A, the current current signal is set to 300A to control the current signal within a set threshold range.

[0101] Optionally, the second duration may be specifically 0-2 ms, which is not limited in this application.

[0102] See also Figure 4 , Figure 4 : is a flow chart of the third embodiment of the control method of the welding power supply of the present application. The control method of the welding power supply of this embodiment is Figure 1 A flow chart of a detailed implementation of the control method of the welding power source in the embodiment of the present invention specifically includes the following steps:

[0103] S31: Acquire characteristic parameters of the electrical signal between the welding wire and the base material.

[0104] S32: Determine the current stage of the droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal.

[0105] Among them, S31 and S32 are Figure 1 S11 and S12 are the same. For details, please refer to S11 and S12 and their related text descriptions, which will not be repeated here.

[0106] S33: In response to the droplet short-circuit transition period entering the initial short-circuit stage, adjusting the current signal to a third current value.

[0107] It is understandable that when the welding power supply 101 determines that the molten droplet short-circuit transition cycle has entered the initial short-circuit stage, it specifically adjusts the current current signal to a preset constant value, that is, the third current value, and maintains forward control to achieve the best molten droplet transfer characteristics while reducing welding spatter caused by excessive short-circuit current.

[0108] Optionally, the third current value may be specifically 10-300A, which is not limited in the present application.

[0109] S34: after the third current value is maintained for a third period of time, the fourth change speed is used to adjust the increasing current signal.

[0110] Furthermore, after maintaining the third current value for a third period of time, the welding power source 101 specifically continuously increases the current signal at a fourth change speed.

[0111] Optionally, the third duration may be specifically 0-1 ms, which is not limited in this application.

[0112] Optionally, the fourth change speed may specifically be 30-1000A / ms, which is not limited in the present application.

[0113] S35: In response to the droplet short-circuit transition period entering the initial arcing stage, the current signal is adjusted from positive to negative.

[0114] S36: Adjusting the average voltage of the voltage signal during the droplet short-circuit transition period to within a constant threshold range.

[0115] Among them, S35 and S36 are Figure 1 S13 and S14 are the same. For details, please refer to S13 and S14 and their related text descriptions, which will not be repeated here.

[0116] Furthermore, in one embodiment, after S34 and before S35, the process may further include: after the fourth change speed is used to adjust the increasing current signal for a fourth time period, the fifth change speed is used to adjust the increasing current signal.

[0117] Among them, the fifth change speed is lower than the fourth change speed.

[0118] Optionally, the fifth change speed may specifically be 30-1000A / ms, which is not limited in the present application.

[0119] It is understandable that when the positive current value of the current signal is large, when it is necessary to reduce it or change the polarity, that is, adjust the positive current to a negative current, there is a problem that is difficult to achieve, and even the welding power supply 101 with poor performance cannot effectively adjust the positive current to a suitable negative current within the preset time. Therefore, in the initial stage of short circuit, the welding power supply 101 needs to use different change speeds in stages, that is, the fourth change speed and the fifth change speed to adjust and increase the current signal, and make the fifth change speed less than the fourth change speed, so as to reduce the positive current value of the current signal at the end of the initial stage of short circuit as much as possible, that is, by reducing the short-circuit current peak value, it is convenient to change the polarity in the subsequent stage.

[0120] Furthermore, the current signal is adjusted and increased by multiple change speeds, which can effectively reduce the occurrence of welding spatter to ensure welding quality.

[0121] In other embodiments, after the fifth change speed is used to adjust and increase the current signal for the fifth period of time, the sixth change speed, the seventh change speed, the eighth change speed and any reasonable number of different change speeds can be used in sequence to adjust and increase the current signal, and the change speeds after the fourth change speed are reduced in sequence in order to reduce the forward current value of the current signal at the end of the initial stage of the short circuit as much as possible, to facilitate the subsequent polarity change, and to use multiple different change speeds to effectively reduce welding spatter and promote droplet separation.

[0122] Optionally, the duration from the welding power supply 101 using the fourth speed change to increase the current signal to the end of the initial short circuit stage is 0-2ms, which is not limited in the present application.

[0123] Optionally, the current value of the current signal at the end of the initial short circuit stage may be 600-700A, which is not limited in the present application.

[0124] See also Figure 5 and Figure 6 ,in, Figure 5 is a flow chart of a fourth embodiment of a control method for a welding power source of the present application, Figure 6 yes Figure 5 The waveform diagram of the current and voltage signals corresponding to S41-S415 in one embodiment. The control method of the welding power supply in this embodiment is Figure 1 A flow chart of a detailed implementation of the control method of the welding power source in the embodiment of the present invention specifically includes the following steps:

[0125] S41: Acquire characteristic parameters of the electrical signal between the welding wire and the base material.

[0126] Specifically, Figure 6As shown, the welding power source 101 samples and obtains the electrical signal and its characteristic parameters between the welding wire 102 and the base material 201 in real time.

[0127] Among them, the electrical signal includes a current signal and a voltage signal between the welding wire 102 and the base material 201; the characteristic parameters of the electrical signal include the current value of the current signal, the voltage value of the voltage signal, the rising speed and falling speed of the voltage signal, the rising amplitude and falling amplitude of the voltage signal, the instantaneous power and instantaneous power change rate of the electrical signal and other reasonable parameters, and the present application does not limit this.

[0128] S42: Detect whether the decreasing speed and / or decreasing amplitude of the voltage signal exceeds a second set threshold.

[0129] It can be understood that the arcing late stage in one droplet short-circuit transition cycle enters the short-circuit initial stage of another droplet short-circuit transition cycle, that is, at time T0, the conductive state between the welding wire 102 and the base material 201 will rapidly switch from mutual disconnection to a short-circuit state, so that the voltage signal between the welding wire 102 and the base material 201 drops rapidly, thereby being able to use the detection of the falling speed and / or falling amplitude of the voltage signal to judge whether the current state has entered the initial stage of the short circuit.

[0130] Among them, the second set threshold can be reasonably set according to the signal sampling, analysis and statistics in the actual welding scene, so that when it is determined that the falling speed and / or the falling amplitude of the voltage signal exceeds the second set threshold, it can be determined that the molten droplet short-circuit transition period enters the initial stage of short circuit. This application does not limit this.

[0131] If the decreasing speed and / or decreasing amplitude of the voltage signal does not exceed the second set threshold, S43 is executed; if the decreasing speed and / or decreasing amplitude of the voltage signal exceeds the second set threshold, S44 is executed.

[0132] S43: Maintain the current adjustment state.

[0133] S44: Determine that the droplet short-circuit transition period enters the initial short-circuit stage, and adjust the current signal to a third current value.

[0134] It is understandable that if Figure 6 As shown in the waveform corresponding to the current signal A, when the welding power supply 101 determines that the molten droplet short-circuit transition cycle enters the initial short-circuit stage, it specifically adjusts the current current signal to a preset constant value, that is, the third current value, and maintains positive control to achieve the best molten droplet transfer characteristics while reducing welding spatter caused by excessive short-circuit current.

[0135] Optionally, the third current value may be specifically 10-300A, which is not limited in the present application.

[0136] S45: After the third current value is maintained for a third period of time, the fourth change speed is used to adjust the increasing current signal.

[0137] Furthermore, after maintaining the third current value for a third period of time, the welding power source 101 continuously increases the current signal at a fourth change speed.

[0138] Optionally, the third duration may be specifically 0-1 ms, which is not limited in this application.

[0139] Optionally, the fourth change speed may specifically be 30-1000A / ms, which is not limited in the present application.

[0140] S46: after the fourth change speed is used to adjust the increasing current signal for a fourth time period, the fifth change speed is used to adjust the increasing current signal.

[0141] The fifth change speed is smaller than the fourth change speed.

[0142] Optionally, the fifth change speed may specifically be 30-1000A / ms, which is not limited in the present application.

[0143] Optionally, the duration from the welding power supply 101 using the fourth speed change to increase the current signal to the end of the initial short circuit stage is 0-2ms, which is not limited in the present application.

[0144] Optionally, the current value of the current signal at the end of the initial short circuit stage may be 600-700A, which is not limited in the present application.

[0145] S47: Detect whether the instantaneous power and / or the instantaneous power change rate exceeds a third set threshold.

[0146] It is worth explaining that the molten droplet necking stage specifically refers to the stage when the end of the welding wire 102 melts and separates from the main body of the welding wire 102 to transition from a short circuit between the welding wire 102 and the base material 201 to the re-ignition of the welding wire 102. During this stage, the instantaneous power and the instantaneous power change rate of welding will exceed a certain critical value, so that the critical value can be utilized, that is, the detection of whether the instantaneous power and / or the instantaneous power change rate exceeds the third set threshold value to determine whether the molten droplet short-circuit transition cycle has entered the molten droplet necking stage.

[0147] If the instantaneous power and / or the instantaneous power change rate does not exceed the second set threshold, S48 is executed; if the instantaneous power and / or the instantaneous power change rate exceeds the second set threshold, S49 is executed.

[0148] S48: Maintain the current adjustment state.

[0149] S49: Determine that the molten droplet short-circuit transition period enters the molten droplet necking stage, and adjust the current signal to a first positive current value.

[0150] Specifically, when the welding power supply 101 determines that the current droplet short-circuit transition cycle enters the droplet necking stage, that is, at time T1, it quickly adjusts the current signal down to a preset positive first current value to reduce welding spatter and wait for the initial arcing stage to arrive.

[0151] Optionally, the first current value may be specifically 20-200A, which is not limited in the present application.

[0152] Optionally, the duration of the droplet necking stage does not exceed 2 ms (milliseconds), which is not limited in the present application.

[0153] S410: Detect whether the rising speed of the voltage signal exceeds a first set threshold.

[0154] It can be understood that when the molten droplet short-circuit transition cycle enters the initial stage of arcing, the conductive state between the welding wire 102 and the base material 201 will quickly switch from a short circuit to an open circuit state, so that the voltage signal between the welding wire 102 and the base material 201 will increase rapidly, thereby being able to use the detection of the rising speed of the voltage signal to determine whether the current state has entered the initial stage of arcing.

[0155] Among them, the first set threshold can be reasonably set according to the signal sampling, analysis and statistics in the actual welding scene, so that when it is determined that the rising speed of the voltage signal exceeds the second set threshold, it can be determined that the molten droplet short-circuit transition cycle enters the initial stage of arcing. This application does not limit this.

[0156] If the rising speed of the voltage signal does not exceed the second set threshold, S411 is executed; if the rising speed of the voltage signal exceeds the second set threshold, S412 is executed.

[0157] S411: Maintain the current adjustment state.

[0158] S412: Determine that the molten droplet short-circuit transition period enters the initial arcing stage, use a first change speed to adjust the current signal from a positive first current value to a negative first current value, and maintain the negative first current value until the initial arcing stage ends.

[0159] It can be understood that when the welding power supply 101 determines that the molten droplet short-circuit transition period has entered the initial stage of arcing, that is, at time T2, it specifically uses a first change speed to adjust the current signal from a positive first current value to a negative first current value, and maintains the negative first current value until the end of the initial stage of arcing, so as to utilize the negative current in the initial stage of arcing and its duration to reduce the heat input of welding as much as possible.

[0160] Optionally, the first change speed may be 500-1000A / ms (ampere / millisecond), that is, in the initial stage of arcing, the current signal is adjusted from the positive first current value to the negative first current value at a speed of decreasing by 500-1000A (ampere) per millisecond.

[0161] Optionally, the first current value may be specifically 20-200A, which is not limited in the present application.

[0162] S413: After the initial arcing stage lasts for a first time period, it is determined that the droplet short-circuit transition period enters the later arcing stage, and the current signal is adjusted from the negative first current value to 0 using a second change speed.

[0163] It is understandable that the welding power supply 101 specifically determines whether the molten droplet short-circuit transition period has entered the late arcing stage based on the current duration of the initial arcing stage, so as to adjust the current signal from the negative first current value to 0 using a second change speed when entering the late arcing stage, that is, at time T3.

[0164] The second change speed may specifically be the adjustment limit of the hardware performance of the welding power source 101 itself, and the current signal is adjusted from the negative first current value to 0 at the fastest change speed.

[0165] Optionally, the first duration may be specifically 0-2 ms, which is not limited in this application.

[0166] S414: Use a third change speed to adjust the current signal from 0 to a second positive current value.

[0167] Optionally, the third change speed may specifically be 500-1000A / ms, which is not limited in the present application.

[0168] Optionally, the second current value is 30-300A, which is not limited in the present application.

[0169] S415: Adjusting the average voltage of the voltage signal during the droplet short-circuit transition period to within a constant threshold range.

[0170] Specifically, the remaining time from the late arcing stage to the early stage of the next short circuit is used to adjust the average voltage of the voltage signal in a complete droplet short circuit transition cycle to a constant threshold range using a constant voltage control algorithm, so as to retain the self-regulating effect of the arc 301 and avoid problems such as loss of control of the arc 301 length and decreased wettability of the molten pool caused by controlling the droplet size; and through average voltage control, the overall voltage is guaranteed to be constant, that is, from a macroscopic point of view, the average length of the arc 301 is constant, thereby ensuring the consistency of welding and the uniformity of the weld.

[0171] Optionally, the constant threshold may be specifically 10-50V (volts), which is not limited in the present application.

[0172] It is worth noting that the initial short-circuit stage in the molten droplet short-circuit transition cycle specifically corresponds to the T0-T1 period, the molten droplet necking stage corresponds to the T1-T2 period, the initial arcing stage corresponds to the T2-T3 period, and the late arcing stage corresponds to the T3 to T0 period of the next molten droplet short-circuit transition cycle.

[0173] The above scheme, by realizing the polarity switching of the current signal within each molten droplet short-circuit transition cycle, effectively retains the efficiency of adjusting the distribution of electric energy between the welding wire 102 and the molten pool by adjusting the duration of the negative current, thereby effectively ensuring good and consistent welding quality without affecting the molten droplet transition and droplet size, without affecting the stability of the arc 301, and reducing the heat input of welding.

[0174] In addition, constant voltage control is adopted in the arc base stage, that is, the later stage of arc burning, which retains the self-regulating function of the arc 301 and avoids problems such as loss of control of the arc 301 length and decreased wettability of the molten pool caused by controlling the droplet size; at the same time, through average voltage control, the overall voltage is effectively guaranteed to be constant, that is, from a macroscopic point of view, the average length of the arc 301 is constant, thereby ensuring the consistency of welding and the uniformity of the weld.

[0175] In the initial stage of short circuit and the stage of droplet necking, the use of forward current control can effectively promote the droplet transfer, thereby avoiding the use of reverse current to hinder the droplet transfer.

[0176] In addition, setting the negative current time at the initial stage of arcing can also avoid the control timing failure problem caused by the inconstant molten droplet short-circuit transition period to the greatest extent.

[0177] Further, in one embodiment, if Figure 6 As shown in the waveform corresponding to the current signal B, the above S414 and S415 can also be specifically replaced by: adjusting the current signal to a set pulse signal, and making the average voltage of the voltage signal in the droplet short-circuit transition period be within a constant threshold range.

[0178] It is understandable that in order to further improve the weld formation, a method of alternating control of positive pulse current and negative pulse current can be specifically adopted in the arc burning stage. For example, after the current signal is adjusted from positive to negative in the initial stage of arc burning, the current signal is adjusted to a set pulse signal, and at the same time, a constant voltage regulation algorithm is used to adjust the average voltage of the voltage signal in a molten droplet short-circuit transition cycle to a constant threshold range until the end of the late stage of arc burning.

[0179] The positive and negative pulse widths of the set pulse signal are small, i.e., "narrow pulse widths", which are used to control the energy of the droplet, i.e., the energy of the droplet is supplied in a digital manner. By controlling the current rising and falling slopes when the positive and negative narrow pulse widths are switched, the arc 301 stiffness can be indirectly controlled and the welding stability can be improved.

[0180] The positive and negative adjustment of "narrow pulse width" can more accurately control the energy of droplet formation, thereby effectively controlling the droplet size; at the same time, the adjustment control of the change speed when switching between positive and negative pulses can effectively improve the arc 301 stiffness and welding stability.

[0181] This application also provides a short-circuit transition welding method, see Figure 7 , Figure 7 This is a schematic flow chart of the first embodiment of the short-circuit transition welding method of the present application. Specifically, it may include the following steps:

[0182] S51: Output electrical signals to the welding wire and the base material.

[0183] It is understandable that if Figure 2 As shown, the short-circuit transition welding method in this embodiment is specifically a method in which the short-circuit transition welding device 100 welds the parent material 201 by melting the welding wire 102. The short-circuit transition welding device 100 includes a welding power source 101 and a welding wire 102 connected to each other.

[0184] Specifically, the welding power source 101 outputs an electrical signal to the welding wire 102 and the base material 201 outside the short-circuit transfer welding device 100 .

[0185] S52: The electrical signal is adjusted by using a preset control method, so as to utilize the electrical signal to melt the welding wire and weld the base material.

[0186] Furthermore, the welding power source 101 uses a preset control method to adjust the electrical signal so as to utilize the electrical signal to melt the welding wire 102 and weld the base material 201 .

[0187] It should be noted that the preset control method described in this embodiment is the control method of the welding power source 101 described in any of the above embodiments. Figure 1-6 And the related text content will not be repeated here.

[0188] See also Figure 8 , Figure 8 The short circuit transition welding method of the present invention is a schematic diagram of the process of the second embodiment of the short circuit transition welding method. Figure 7 A schematic flow chart of a detailed implementation of the short-circuit transition welding method in the embodiment of the present invention specifically includes the following steps:

[0189] S61: Output electrical signals to the welding wire and the base material.

[0190] S62: The electrical signal is adjusted by using a preset control method so as to utilize the electrical signal to melt the welding wire and weld the base material.

[0191] Among them, S61 and S62 are Figure 7 S51 and S52 are the same. For details, please refer to S51 and S52 and their related text descriptions, which will not be repeated here.

[0192] S63: driving the welding wire to move towards or away from the base material according to the current stage of the droplet short-circuit transition cycle, and controlling the average speed of the welding wire during the droplet short-circuit transition cycle to be within a set speed threshold.

[0193] It is understandable that the short-circuit transition welding device 100 specifically also includes a driving mechanism 103, which connects the welding power supply 101 and the welding wire 102 to receive the driving control signal sent by the welding power supply 101 according to the current stage of the molten droplet short-circuit transition cycle, and drives the welding wire 102 to move toward or away from the base material 201 according to the current stage of the molten droplet short-circuit transition cycle. Specifically, it can be to move in the direction of approaching the base material 201 at a first movement speed, or to move in the direction of moving away from the base material 201 at a second movement speed, so as to reasonably adjust the distance between the welding wire 102 and the base material 201 at different stages, and control the average speed of the welding wire 102 in the molten droplet short-circuit transition cycle within the set speed threshold, so as to effectively ensure the consistency of the welding process and the uniformity of the weld.

[0194] It is worth noting that the first movement speed and the second movement speed are in opposite directions, and the driving mechanism 103 reasonably selects the first movement speed and / or the second movement speed according to each stage in the molten droplet short-circuit transition cycle, and dynamically adjusts the speed to control the average speed within the set speed threshold.

[0195] In addition, the welding wire 102 is specifically fed into the wire feeding tube of the welding gun at a certain speed by the driving mechanism 103 in the short-circuit transition welding device 100 to melt it by the electric arc 301. The feeding speed of the welding wire 102 is consistent with the melting speed of the welding wire 102 to ensure the stability of the welding process. Therefore, the feeding speed of the welding wire 102 is an important factor affecting the stability of the welding process.

[0196] See also Fig. 9 and Fig.10 ,in, Fig. 9 yes Figure 8 The flow chart of S63 in the embodiment of FIG. Fig.10 yes Fig. 9The waveform diagram of the current, voltage signal and wire feeding speed corresponding to S631-S632 in one embodiment. In one embodiment, the short-circuit transition welding method of the present application includes some more specific steps in addition to the above S61-S63. Specifically, the above S63 may also include the following steps:

[0197] S631: In the initial stage and the later stage of arc burning, the welding wire is driven to move toward the base material at a first movement speed.

[0198] It is understandable that if Fig.10 As shown in the waveform corresponding to the medium movement speed C, the driving mechanism 103 in the short-circuit transition welding device 100 specifically drives the welding wire 102 to move toward the direction close to the base material 201 at the first movement speed in the initial stage and the later stage of arcing.

[0199] S632: In the initial stage of short circuit and the stage of droplet necking, the welding wire is driven to move in a direction away from the base material at a second movement speed, and the average speed of the welding wire during the droplet short circuit transition period is controlled within a set speed threshold.

[0200] Furthermore, the driving mechanism 103 specifically drives the welding wire 102 to move in a direction away from the base material 201 at a second movement speed in the initial stage of short circuit and the stage of molten droplet necking, and specifically reasonably adjusts the speed of the second movement speed according to the speed and duration of the first movement speed in the initial stage of arcing and the later stage of arcing, so as to achieve the average speed of the welding wire 102 in the molten droplet short circuit transition period being controlled within a set speed threshold.

[0201] Optionally, the first movement speed is greater than or equal to the second movement speed, but the two are in opposite directions.

[0202] It can be understood that the overall wire feeding speed is adjusted to be constant through average speed control, that is, the wire feeding is kept at a constant speed on a macro scale, thereby effectively ensuring the consistency of the welding process and the uniformity of the weld.

[0203] This application also provides a welding power source, see Fig.11 , Fig.11 1 is a schematic diagram of the structure of the first embodiment of the welding power supply of the present application. In this embodiment, the welding power supply 70 includes: a main control circuit 71 and a sampling circuit 72.

[0204] Specifically, the main control circuit 71 is coupled to an external welding wire (not shown) and a base material (not shown) to output an electrical signal to the welding wire and the base material; the sampling circuit 72 is coupled to the welding wire, the base material and the main control circuit 71 to sample and obtain the electrical signal between the welding wire and the base material in real time, and send the electrical signal to the main control circuit 71, so that the main control circuit 71 uses the control method of the welding power source 70 described in any one of the above embodiments to adjust the electrical signal, so as to use the electrical signal to melt the welding wire and weld the base material. For details, please refer to Figure 1-6 And the related text content will not be repeated here.

[0205] See also Fig.12 , Fig.12 The difference between the welding power supply in this embodiment and the welding power supply in the first embodiment provided by the present application is that the welding power supply 80 further includes a filter circuit 83 .

[0206] Specifically, the filter circuit 83 is coupled to the sampling circuit 82 and the main control circuit 81. The filter circuit 83 is used to receive the electrical signal sent by the sampling circuit 82, and to filter the electrical signal and send it to the main control circuit 81, so that the main control circuit 81 uses the filtered electrical signal to adjust the electrical signal using the control method of the welding power supply 80 described in any one of the above embodiments, so as to use the electrical signal to melt the welding wire and weld the base material, thereby effectively eliminating interference and improving the accuracy of the output control of the welding power supply 80. For details, please refer to Figure 1-6 And the related text content will not be repeated here.

[0207] It is understandable that, in this embodiment, the sampling circuit 82 and the main control circuit 81 are respectively the same as the sampling circuit 72 and the main control circuit 71. For details, please refer to Fig.11 And the related text content will not be repeated here.

[0208] This application also provides a short-circuit transition welding device, please continue to refer to Figure 2 , Figure 2 1 is a schematic diagram of the structure of an embodiment of a welding power source of the present application. In this embodiment, the short-circuit transition welding device 100 specifically includes a welding power source 101 and a welding wire 102 .

[0209] Specifically, the welding power source 101 is connected to the welding wire 102 and the external base material 201; wherein the welding power source 101 is used to output an electrical signal to the welding wire 102 and the base material 201, and the control method of the welding power source 101 as described in any one of the above embodiments is used to adjust the electrical signal, so as to use the electrical signal to generate a gas arc 301 between the welding wire 102 and the base material 201, thereby melting the welding wire 102 and welding the base material 201. For details, please refer to Figure 1-6And the related text content will not be repeated here.

[0210] Furthermore, in one embodiment, the short-circuit transition welding device 100 specifically also includes a driving mechanism 103, which is connected to the welding power supply 101 and the welding wire 102. The driving mechanism 103 is used to receive a driving control signal sent by the welding power supply 101 according to the current stage of the molten droplet short-circuit transition cycle, so as to drive the welding wire 102 to move in a first movement speed toward the direction approaching the base material 201, or to move in a second movement speed toward the direction away from the base material 201 based on the driving control signal.

[0211] Specifically, the driving mechanism 103 drives the welding wire 102 to move toward the base material 201 at a first speed in the initial stage of arcing and the later stage of arcing; and drives the welding wire 102 to move away from the base material 201 at a second speed in the initial stage of short circuit and the stage of molten droplet necking.

[0212] In one embodiment, the short-circuit transition welding device 100 further includes a resistor 104 , which is coupled between the welding power source 101 and the welding wire 102 .

[0213] The beneficial effects of the present application are as follows: Different from the prior art, the control method of the welding power supply provided by the present application obtains the characteristic parameters of the electrical signal between the welding wire and the base material, and determines the current stage of the molten droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal. When the molten droplet short-circuit transition cycle enters the initial stage of arcing, the current signal is adjusted from positive to negative, and the average voltage of the voltage signal in the molten droplet short-circuit transition cycle is adjusted to a constant threshold range, so as to realize the polarity change of the current signal in one molten droplet short-circuit transition cycle, thereby effectively reducing the overall welding heat input during the welding process, thereby reducing ineffective power consumption and reducing the risk of welding defects such as "bite edge"; and by adopting constant voltage regulation in the later stage of arcing, the self-regulation ability of the arc is effectively guaranteed, thereby effectively improving the stability of the arc, as well as the good and consistent welding quality, and making the application range of the welding power supply control method wider.

[0214] The above description is only an implementation method of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for controlling a welding power source, characterized in that: The control method of the welding power supply comprises: Acquire characteristic parameters of the electrical signal between the welding wire and the base material; wherein the electrical signal includes a current signal and a voltage signal; Determining the current stage of the droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal; In response to the droplet short-circuit transition period entering the initial arcing stage, adjusting the current signal from a positive direction to a negative direction; After the arcing initial stage lasts for a first time period, determining that the droplet short-circuit transition period enters the arcing late stage, and adjusting the current signal from the negative first current value to 0 using a second change speed; Using a third change speed to adjust the current signal from 0 to a second positive current value; or, using the third change speed to adjust the current signal for a second time period; The average voltage of the voltage signal during the droplet short circuit transition period is adjusted to be within a constant threshold range.

2. The control method of welding power source according to claim 1, characterized in that: The characteristic parameters of the electrical signal also include the rising speed of the voltage signal. The step of determining the current stage of the droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal includes: Detecting whether the rising speed exceeds a first set threshold; In response to the rising speed exceeding the first set threshold, it is determined that the droplet short-circuit transition period enters the initial arcing stage.

3. The control method of welding power source according to claim 1, characterized in that: The step of adjusting the current signal from a positive direction to a negative direction comprises: The current signal is adjusted from the first positive current value to the first negative current value using a first change speed, and the first negative current value is maintained until the initial arcing stage ends.

4. The control method of welding power source according to claim 1, characterized in that: The step of adjusting the average voltage of the voltage signal in the droplet short circuit transition period to a constant threshold range comprises: The current signal is adjusted to a set pulse signal, and the average voltage of the voltage signal in the droplet short-circuit transition period is within the constant threshold range.

5. The control method of welding power source according to claim 1, characterized in that: The control method of the welding power supply also includes: In response to the droplet short-circuit transition period entering the short-circuit initial stage, adjusting the current signal to a third current value; After the third current value is maintained for a third period of time, the current signal is increased by adjusting the fourth change speed.

6. The control method of welding power source according to claim 5, characterized in that: After the step of maintaining the third current value for a third time period and increasing the current signal by using a fourth change speed, the method further includes: After the fourth change speed is used to adjust and increase the current signal for a fourth time period, the fifth change speed is used to adjust and increase the current signal; wherein the fifth change speed is lower than the fourth change speed.

7. The control method of welding power source according to claim 5 or 6, characterized in that: The characteristic parameters of the electrical signal also include the falling speed and / or the falling amplitude of the voltage signal. The step of determining the current stage of the droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal includes: Detecting whether the descent speed and / or the descent amplitude exceeds a second set threshold; In response to the descending speed and / or the descending amplitude exceeding a second set threshold, it is determined that the droplet short-circuit transition period enters the short-circuit initial stage.

8. The control method of welding power source according to claim 1, characterized in that: The control method of the welding power supply also includes: In response to the droplet short-circuit transition period entering the droplet necking stage, the current signal is adjusted to a positive first current value.

9. The control method of welding power source according to claim 8, characterized in that: The characteristic parameters of the electrical signal further include instantaneous power and / or instantaneous power change rate. The step of determining the current stage of the droplet short-circuit transition cycle between the welding wire and the base material based on the characteristic parameters of the electrical signal includes: Detecting whether the instantaneous power and / or the instantaneous power change rate exceeds a third set threshold; In response to the instantaneous power and / or the instantaneous power change rate exceeding a third set threshold, it is determined that the droplet short-circuit transition period enters the droplet necking stage.

10. A short-circuit transition welding method, characterized in that: The short-circuit transition welding method comprises: Outputting electrical signals to the welding wire and the base material; wherein the electrical signals include current signals and voltage signals; The electrical signal is adjusted by using the control method of the welding power source as described in any one of claims 1 to 9, so as to utilize the electrical signal to melt the welding wire and weld the base material.

11. The short-circuit transition welding method according to claim 10, characterized in that: The short-circuit transition welding method also includes: The welding wire is driven to move toward or away from the base material according to the current stage of the molten droplet short-circuit transition cycle, and the average speed of the welding wire during the molten droplet short-circuit transition cycle is controlled within a set speed threshold.

12. The short-circuit transition welding method according to claim 11, characterized in that: The step of driving the welding wire to move toward or away from the base material according to the current stage of the molten droplet short-circuit transition cycle, and controlling the average speed of the welding wire in the molten droplet short-circuit transition cycle to be within a set speed threshold comprises: In the initial stage of arc burning and the later stage of arc burning, the welding wire is driven to move toward the parent material at a first moving speed; In the initial short circuit stage and the droplet necking stage, the welding wire is driven to move in a direction away from the base material at a second movement speed, and the average speed of the welding wire during the droplet short circuit transition period is controlled within the set speed threshold.

13. A welding power source, characterized in that: The welding power source comprises: A main control circuit coupled to an external welding wire and a base material to output an electrical signal to the welding wire and the base material; A sampling circuit is coupled to the welding wire, the base material and the main control circuit to sample and obtain the electrical signal between the welding wire and the base material in real time, and send the electrical signal to the main control circuit so that the main control circuit adjusts the electrical signal using the control method of the welding power supply as described in any one of claims 1-9.

14. A short-circuit transition welding device, characterized in that: The short-circuit transition welding device comprises a welding power source and a welding wire, wherein the welding power source is connected to the welding wire and an external parent material; Wherein, the welding power supply is used to output electrical signals to the welding wire and the base material, and the electrical signals are adjusted by using the control method of the welding power supply as described in any one of claims 1-9, so as to utilize the electrical signals to melt the welding wire and weld the base material.

15. The short-circuit transition welding device according to claim 14, characterized in that: The short-circuit transition welding device also includes a driving mechanism, which is connected to the welding power supply and the welding wire. The driving mechanism receives a driving control signal sent by the welding power supply according to the current stage of the molten droplet short-circuit transition cycle, so as to drive the welding wire to move in a direction approaching the base material at a first movement speed, or to move in a direction away from the base material at a second movement speed based on the driving control signal.

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