A short-circuit energy control method and system for metal-arc gas shielded welding

Abstract

The present invention discloses a short-circuit energy control method and system for metal-metal gas shielded welding, which belongs to the technical field of metal-metal gas shielded welding. The method comprises: obtaining a short-circuit current value and a short-circuit voltage value; calculating the short-circuit extension length using the short-circuit current value and the short-circuit voltage value; calculating the short-circuit extension change rate and the short-circuit extension acceleration according to the short-circuit extension length; using the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration, adopting a fuzzy control method to obtain the short-circuit control current; and calculating the short-circuit energy according to the short-circuit control current. The present invention calculates the short-circuit resistance by collecting the characteristic points of the short-circuit waveform, namely the short-circuit current and the short-circuit voltage. The resistance value of the short-circuit resistance can reflect the extension length. According to the calculated extension change rate and extension acceleration, the fuzzy control strategy is combined to control the change of the short-circuit current, promote the formation of necking, and reduce the spattering generated during the short-circuit process.

Description

Technical Field

[0001] The present invention relates to the technical field of gas metal arc welding, and in particular to a short-circuit energy control method and system for gas metal arc welding. Background Art

[0002] Gas Metal Arc Welding (GMAW), the most widely used welding process, includes short-circuiting as one of its fundamental techniques. However, short-circuiting, especially in CO2 welding, is often associated with significant spatter and poor weld formation.

[0003] The short-circuit transition form of gas metal arc welding (GMAW) is the basic transition form of GMAW. Its advantage lies in its low heat input, but its disadvantage lies in the difficulty in controlling the dynamic characteristics, which can produce welding spatter. Because the wire through which the welding current flows is long and there are many ferromagnetic objects around it, there is a large reactance in the circuit, and the current cannot be switched down quickly. In addition, production practice has shown that extremely fast switching of large currents before the short circuit ends is very difficult, and sometimes even impossible. Regarding the dynamic characteristics of short-circuit transition, there is an urgent need for a method that can solve the problem of energy control during the short-circuit stage of the short-circuit transition process. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a short-circuit energy control method for metal-electrode gas shielded welding, which can effectively improve the dynamic characteristics of the short-circuit transition process and reduce the spatter generation during the short-circuit process.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] In one aspect, the present invention provides a method for controlling short-circuit energy of gas metal arc welding, comprising:

[0007] Obtain short-circuit current value and short-circuit voltage value;

[0008] Calculating the short-circuit extension length using the short-circuit current value and the short-circuit voltage value;

[0009] Calculating the short-circuit stem extension change rate and the short-circuit stem extension acceleration according to the short-circuit stem extension length;

[0010] The short-circuit current, the short-circuit stem extension change rate and the short-circuit stem extension acceleration are used to obtain the short-circuit control current by adopting a fuzzy control method;

[0011] The short-circuit energy is calculated according to the short-circuit control current.

[0012] Optionally, obtaining the short-circuit voltage value includes:

[0013] In one control cycle, DSP multi-channel is used to collect voltages m times, and the average value of the m voltages is calculated to obtain the short-circuit voltage value; where m>1.

[0014] Optionally, the short-circuit stem extension length is shown as:

[0015] L n =f(R n );

[0016] R n =U n / I n ;

[0017] Where, L n Indicates the nth short circuit extension length; R n represents the nth short-circuit resistance value; f(·) represents the relationship function between the stem extension length and the short-circuit resistance; U n Indicates the nth short-circuit voltage value; I n Indicates the nth short-circuit current value.

[0018] Optionally, the short-circuit stem extension change rate and the short-circuit stem extension acceleration are expressed as:

[0019] △△L n =△L n -△L n-1 ;

[0020] △L n =L n -L n-1 ;

[0021] Where, △△L n Indicates the nth short-circuit extension acceleration; △L n Indicates the rate of change of stem extension after the nth short circuit; △L n-1 Indicates the change rate of the stem extension at the n-1th short circuit; L n Indicates the nth short-circuit extension length; L n-1 Indicates the n-1th short-circuit extension length.

[0022] Optionally, the short-circuit stem extension change rate and the short-circuit stem extension acceleration are used to obtain the short-circuit control current using a fuzzy control method, including:

[0023] If the short-circuit extension change rate is greater than zero, the current welding process is in the gun-pulling state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration;

[0024] If the short-circuit extension change rate is zero and the short-circuit extension acceleration is zero, the current welding process is in a stable state, and the short-circuit control current is equal to the short-circuit current;

[0025] If the short-circuit extension change rate is less than zero, the current welding process is in the gun pressing state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration.

[0026] Optionally, if the short-circuit extension change rate is greater than zero, the current welding process is in the gun-pulling state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate, and the short-circuit extension acceleration, including:

[0027] If the short-circuit extension change rate is greater than zero, and the short-circuit extension acceleration is greater than zero, the current welding process is in the accelerated gun pulling state, and the short-circuit control current is expressed as:

[0028] I b =I a +(-20000)*△L n +(-200)*△△L n ;

[0029] If the short-circuit extension change rate is greater than zero and the short-circuit extension acceleration is zero, the current welding process is in a uniform gun pulling state, and the short-circuit control current is expressed as:

[0030] I b =I a +(-10000)*△L n +(-100)*△△L n ;

[0031] If the short-circuit extension change rate is greater than zero and the short-circuit extension acceleration is less than zero, the current welding process is in the deceleration gun pulling state, and the short-circuit control current is expressed as:

[0032] I b =I a +(-10000)*△L n +(-100)*△△L n ;

[0033] Where, I a Indicates short-circuit current; △L n Indicates the rate of change of the stem extension at the nth short circuit; △△L n Indicates the nth short-circuit extension acceleration.

[0034] Optionally, if the short-circuit extension change rate is less than zero, the current welding process is in a gun pressing state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate, and the short-circuit extension acceleration, including:

[0035] If the short-circuit extension change rate is less than zero and the short-circuit extension acceleration is greater than zero, the current welding process is in the accelerated gun pressure state, and the short-circuit control current is expressed as:

[0036] I b =I a + (20000) * △ L n +(200)*△△L n ;

[0037] If the short-circuit extension change rate is less than zero and the short-circuit extension acceleration is zero, the current welding process is in a uniform speed gun pressing state, and the short-circuit control current is expressed as:

[0038] I b =I a + (10000) * △L n +(100)*△△L n ;

[0039] If the short-circuit extension change rate is less than zero, and the short-circuit extension acceleration is less than zero, the current welding process is in the deceleration gun pressure state, and the short-circuit control current is expressed as:

[0040] I b =I a + (10000) * △ L n +(100)*△△L n ;

[0041] Where, I a Indicates short-circuit current; △L n Indicates the nth short circuit n Elongation change rate; △△L n Indicates the nth short-circuit extension acceleration.

[0042] Optionally, the short-circuit energy is expressed as:

[0043] E n = I b 2 R n t;

[0044] Where, I b Indicates the short-circuit control current, R n represents the nth short-circuit resistance; t represents the short-circuit time.

[0045] In a second aspect, the present invention provides a short-circuit energy control system for metal-arc gas shielded welding, comprising:

[0046] The data acquisition module is used to obtain the short-circuit current value and the short-circuit voltage value;

[0047] A stem extension calculation module is used to calculate the short-circuit stem extension length using the short-circuit current value and the short-circuit voltage value;

[0048] Calculating the short-circuit stem extension change rate and the short-circuit stem extension acceleration according to the short-circuit stem extension length;

[0049] A short-circuit control current calculation module is used to: use the short-circuit current, the short-circuit stem extension change rate and the short-circuit stem extension acceleration to obtain the short-circuit control current using a fuzzy control method;

[0050] The short-circuit energy calculation module is used to calculate the short-circuit energy according to the short-circuit control current.

[0051] In a third aspect, the present invention provides a computer-readable storage medium having computer instructions stored thereon, characterized in that when the computer instructions are executed by a processor, the steps of the short-circuit energy control method for metal electrode gas shielded welding described in the first aspect are implemented.

[0052] Compared with the prior art, the present invention has the following beneficial effects:

[0053] The present invention collects the characteristic points of the short-circuit waveform, namely the short-circuit current and the short-circuit voltage, and calculates the short-circuit resistance. The resistance value of the short-circuit resistance can reflect the dry extension length. According to the calculated dry extension change rate and dry extension acceleration, combined with a fuzzy control strategy, the short-circuit current change is controlled, the formation of necking is promoted, the dynamic characteristics of the short-circuit transition process are effectively improved, and the splashing generated during the short-circuit process is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 FIG2 is a flow chart of a method for controlling short-circuit energy of gas metal arc welding according to an embodiment of the present invention;

[0055] Figure 2 FIG2 is a schematic diagram showing key points of a method for controlling short-circuit energy of gas metal arc welding according to an embodiment of the present invention;

[0056] Figure 3 FIG2 is a schematic diagram of collecting short-circuit voltage in one control cycle in one embodiment of the present invention;

[0057] Figure 4 FIG2 is a schematic diagram of collecting short-circuit voltage in one control cycle in another embodiment of the present invention;

[0058] Figure 5Schematic diagram of the membership function of the short-circuit stem extension change rate in one embodiment of the present invention;

[0059] Figure 6 FIG. 1 is a schematic diagram of the membership function of the short-circuit stem extension acceleration in one embodiment of the present invention;

[0060] Figure 7 Schematic diagram of the membership function of the short-circuit stem elongation change rate coefficient in one embodiment of the present invention;

[0061] Figure 8 FIG2 is a schematic diagram of a membership function of a short-circuit stem extension acceleration coefficient in one embodiment of the present invention;

[0062] In the figure: A-short-circuit resistance acquisition point; B-short-circuit control current acquisition point; C-maximum short-circuit current acquisition point; A1-short-circuit voltage point; B1-short-circuit control voltage point; C1-maximum short-circuit voltage point. DETAILED DESCRIPTION

[0063] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present invention and the specific features in the embodiments are detailed descriptions of the technical solution of the present invention, rather than limitations on the technical solution of the present invention. In the absence of conflict, the embodiments of the present invention and the technical features in the embodiments can be combined with each other.

[0064] The term "and / or" simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. Additionally, the character " / " generally indicates an "or" relationship between the related objects.

[0065] Example 1

[0066] like Figure 1 As shown, this embodiment introduces a short-circuit energy control method for metal-arc gas shielded welding, which specifically includes the following steps:

[0067] Step 1: Obtain the short-circuit current and voltage values. The accuracy of current and voltage acquisition directly affects the adjustment of the short-circuit waveform. The accuracy of current acquisition is generally high and is less likely to be affected by external interference. The accuracy of voltage acquisition will be affected by factors such as the length of the output cable, the coiling of the output cable, the voltage CT zero drift, and the large discreteness of the main circuit. Only one voltage acquisition is performed in a single control cycle, which is very accidental. If it is affected by external interference, the acquisition accuracy will be greatly reduced.

[0068] Therefore, collecting the voltage m times (n is a natural number greater than 1) in a single control cycle and calculating the average value of the m voltages can better represent the current actual short-circuit voltage.

[0069] In a specific embodiment, the inverter frequency of the welding power supply is 40 kHz, and the half-cycle control frequency is 80 kHz, that is, the control is performed every 12.5 μs. The ADC sampling function of the control chip DSP is used to collect the current feedback I and voltage feedback U.

[0070] like Figure 3 As shown, in general, a single control cycle (12.5us) only collects one current feedback and one voltage feedback, where the current collection is I a1 , then I a =I a1 ; Voltage acquisition is U a1 , then U a =U a1 .

[0071] like Figure 4 As shown in the figure, in this embodiment, the multi-channel acquisition function of DSP is used, and the trigger signal is changed from 1 to m (m>1), that is, the voltage feedback is acquired m times in a single control cycle, and m=16 at this time. After the acquisition is completed, the acquisition results will be stored in the DSP registers ADCRESULT1~ADCRESULT m And the total time of m sampling is less than 12.5us; among them, the current acquisition is I a1 , then I a =I a1； Voltage acquisition is U a1 To U am , then the average value is calculated: U a = (U a1 +U a2 +…+U am ) / m.

[0072] Step 2: Calculate the short-circuit extension length using the short-circuit current value and the short-circuit voltage value, specifically:

[0073] like Figure 2 As shown, point A is the short-circuit resistance acquisition point. The resistance value collected at this point is approximately equal to the resistance value of the welding wire under the current dry extension length.

[0074] Point B is the point where the short-circuit control current is obtained. The sharply changing current forms a radial electromagnetic contraction force, which promotes the formation of necking. Therefore, by changing the value of this point, the speed of necking formation can be effectively controlled.

[0075] Point C is the point where the maximum short-circuit current is obtained when arcing occurs. It is required to change relatively smoothly so that the necking and breaking process is relatively gentle and the generation of spatter is reduced.

[0076] Point A1 is the short-circuit voltage point and has no practical significance;

[0077] Point B1 is the short-circuit control voltage point and has no practical significance;

[0078] Point C1 is the maximum short-circuit voltage point and has no practical significance;

[0079] A, B, and C are characteristic points of short-circuit current, and A1, B1, and C1 are characteristic points at the corresponding positions of short-circuit voltage.

[0080] The nth short circuit extension length L n Expressed as:

[0081] L n =f(R n );

[0082] R n =U n / I n ;

[0083] Where R n represents the nth short-circuit resistance value; f(·) represents the relationship function between the short-circuit extension length and the short-circuit resistance; U n Indicates the nth short-circuit voltage value; I n Indicates the nth short-circuit current value.

[0084] Step 3: Calculate the short-circuit extension change rate and the short-circuit extension acceleration according to the short-circuit extension length. The nth short-circuit extension change rate ΔL n and the nth short-circuit extension acceleration △△L n Expressed as:

[0085] △△L n =△L n -△L n-1 ;

[0086] △L n =L n -L n-1 ;

[0087] Where, △L n-1 Indicates the change rate of the stem extension at the n-1th short circuit; L n-1 Indicates the n-1th short-circuit extension length.

[0088] In this embodiment, the short-circuit stem extension change rate ΔL n The membership function is as follows Figure 5 As shown, the short-circuit stem extension acceleration △△L n The membership function is as follows Figure 6 As shown, the short-circuit stem extension change rate coefficient △K p The membership function is as follows Figure 7 As shown, the short-circuit stem extension acceleration coefficient △K d The membership function is as follows Figure 8 As shown, △K p , △K d For subsequent calculations I b Use when.

[0089] Step 4: Using the short-circuit current, the short-circuit stem extension change rate and the short-circuit stem extension acceleration, a fuzzy control method is used to obtain the short-circuit control current, and the short-circuit energy is calculated according to the short-circuit control current, specifically:

[0090] In this embodiment, the short-circuit stem extension change rate ΔL n The fuzzy domain is [-0.010, 0.010], and the short-circuit stem extension acceleration △△L n The fuzzy domain is [-0.010, 0.010], and the short-circuit stem extension change rate coefficient △K p The fuzzy domain is determined to be [-20000, 20000], and the short-circuit stem extension acceleration coefficient △K d The fuzzy domain is determined to be [-200, 200], and the fuzzy control rules are shown in Table 1.

[0091] Table 1 Fuzzy control rules table

[0092]

[0093] Use △L n and △△L n It can determine whether the current welding process is in the gun-pressing state or the gun-pulling state. When in the gun-pressing state, the short-circuit transition frequency increases and the droplet particles decrease. At this time, if a short-circuit transition is to occur, more short-circuit energy is required to form a neck in the droplet. Conversely, when in the gun-pulling state, the short-circuit transition frequency decreases and the droplet particles increase. At this time, if a short-circuit transition is to occur, only a smaller short-circuit energy is required to achieve the effect of necking. The purpose is to control the short-circuit energy to control the timing of necking, thereby improving the short-circuit dynamic characteristics.

[0094] The short-circuit control current is expressed as:

[0095] I b =I a +△K p * △L n +△K d * △△L n ;

[0096] The specific fuzzy control method and calculation of short-circuit control current are as follows:

[0097] (1) When △L n >>0, △△L n >>0, indicating that the current welding process is in the state of accelerated gun pulling, then the current at point B is greatly reduced, that is, I b =Ia+(-20000) * △L n +(-200) * △△L n ; At this time △K p =-20000, △K d =-200.

[0098] (2) When △L n >>0, △△L n >0, indicating that the current welding process is in the state of accelerated gun pulling, then the current at point B is greatly reduced, that is, I b =Ia+(-20000) * △L n +(-200) * △△L n .

[0099] (3) When △L n >>0, △△L n =0, indicating that the current welding process is in a state of uniform gun pulling, then the current at point B decreases slightly, that is, I b =Ia+(-10000) * △L n +(-100) * △△L n .

[0100] (4) When △L n >>0, △△L n <0, indicating that the current welding process is in the state of slowing down the gun, then the current at point B is slightly reduced, that is, I b =I a +(-10000) * △L n +(-100) * △△L n .

[0101] (5) When △L n >>0, △△L n <<0, indicating that the current welding process is in the state of slowing down the gun, then the current at point B is slightly reduced, that is, I b =I a +(-10000) * △L n +(-100) * △△L n .

[0102] (6) When △L n >0,△△L n >>0, indicating that the current welding process is in the state of accelerated gun pulling, then the current at point B is greatly reduced, that is, I b =I a +(-20000) * △L n +(-200) * △△L n .

[0103] (7) When △L n >0,△△L n >0, indicating that the current welding process is in the state of accelerated gun pulling, then the current at point B is greatly reduced, that is, I b =I a +(-20000) * △L n +(-200) * △△L n .

[0104] (8) When △L n >0,△△L n =0, indicating that the current welding process is in a state of uniform gun pulling, then the current at point B decreases slightly, that is, I b =I a +(-10000) * △L n +(-100) * △△L n .

[0105] (9) When △L n >0,△△L n <0, indicating that the current welding process is in the state of slowing down the gun, then the current at point B is slightly reduced, that is, I b =I a +(-10000) * △L n +(-100) * △△L n .

[0106] (10) When △L n >0,△△L n <<0, indicating that the current welding process is in the state of slowing down the gun, then the current at point B is slightly reduced, that is, I b =I a +(-10000) * △L n +(-100) * △△Ln .

[0107] (11) When △L n =0, △△L n >>0, this situation does not exist.

[0108] (12) When △L n =0, △△L n >0, the situation does not exist.

[0109] (13) When △L n =0, △△L n =0, indicating that the current welding process is in a stable state, then the current at point B remains unchanged, that is, I b =Ia.

[0110] (14) When △L n =0, △△L n <0, the situation does not exist.

[0111] (15) When △L n =0, △△L n <<0, the situation does not exist.

[0112] (16) When △L n <0, △△L n >>0, indicating that the current welding process is in the state of accelerated gun pressure, then the current at point B increases significantly, that is, I b =I a +(20000) * △L n +(200) * △△L n .

[0113] (17) When △L n <0, △△L n >0, indicating that the current welding process is in the state of accelerated gun pressure, then the current at point B increases significantly, that is, I b =I a +(20000) * △L n +(200) * △△L n .

[0114] (18) When △L n <0, △△L n =0, indicating that the current welding process is in a uniform speed gun pressing state, then the current at point B increases slightly, that is, I b =I a +(10000) * △L n +(100)* △△L n .

[0115] (19) When △L n <0, △△L n <0, indicating that the current welding process is in the state of deceleration and gun pressure, then the current at point B increases slightly, that is, I b =I a +(10000) * △L n +(100) * △△L n .

[0116] (20) When △L n <0, △△L n <<0, indicating that the current welding process is in the state of deceleration and gun pressure, then the current at point B increases slightly, that is, I b =I a +(10000) * △L n +(100) * △△L n .

[0117] (21) When △L n <<0,△△L n >>0, indicating that the current welding process is in the state of accelerated gun pressure, then the current at point B increases significantly, that is, I b =I a +(20000) * △L n +(200) * △△L n .

[0118] (22) When △L n <<0,△△L n >0, indicating that the current welding process is in the state of accelerated gun pressure, then the current at point B increases significantly, that is, I b =I a +(20000) * △L n +(200) * △△L n .

[0119] (23) When △L n <<0,△△L n =0, indicating that the current welding process is in a uniform speed gun pressing state, then the current at point B increases slightly, that is, I b =I a +(10000) * △L n+(100) * △△L n .

[0120] (24) When △L n <<0,△△L n <0, indicating that the current welding process is in the state of deceleration and gun pressure, then the current at point B increases slightly, that is, I b =I a +(10000) * △L n +(100) * △△L n .

[0121] (25) When △L n <<0,△△L n <<0, indicating that the current welding process is in the state of deceleration and gun pressure, then the current at point B increases slightly, that is, I b =I a +(10000) * △L n +(100) * △△L n .

[0122] Where, I b Indicates short-circuit control current; I a Indicates short-circuit current.

[0123] Then the short-circuit energy is expressed as:

[0124] E n = I b 2 R n t;

[0125] Where R n represents the nth short-circuit resistance; t represents the short-circuit time.

[0126] Example 2

[0127] This embodiment introduces a short-circuit energy control system for gas metal arc welding, including:

[0128] The data acquisition module is used to obtain the short-circuit current value and the short-circuit voltage value;

[0129] A stem extension calculation module is used to calculate the short-circuit stem extension length using the short-circuit current value and the short-circuit voltage value;

[0130] Calculating the short-circuit stem extension change rate and the short-circuit stem extension acceleration according to the short-circuit stem extension length;

[0131] A short-circuit control current calculation module is used to: use the short-circuit current, the short-circuit stem extension change rate and the short-circuit stem extension acceleration to obtain the short-circuit control current using a fuzzy control method;

[0132] The short-circuit energy calculation module is used to calculate the short-circuit energy according to the short-circuit control current.

[0133] Example 3

[0134] This embodiment introduces a computer-readable storage medium having computer instructions stored thereon. When the computer instructions are executed by a processor, the steps of the short-circuit energy control method for gas metal arc welding described in Example 1 are implemented.

[0135] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0136] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or block in the flowchart and / or block diagram, as well as the combination of processes and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0137] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0138] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0139] The embodiments of the present invention are described above in conjunction with the accompanying drawings, but the present invention is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms without departing from the scope of protection of the purpose of the present invention and the claims, which are all protected by the present invention.

Claims

1. A method for controlling short-circuit energy of metal-metal gas shielded welding, characterized in that: include: Obtain short-circuit current value and short-circuit voltage value; Calculating the short-circuit extension length using the short-circuit current value and the short-circuit voltage value; Calculating the short-circuit stem extension change rate and the short-circuit stem extension acceleration according to the short-circuit stem extension length; The short-circuit current, the short-circuit stem extension change rate and the short-circuit stem extension acceleration are used to obtain the short-circuit control current by adopting a fuzzy control method; calculating short-circuit energy according to the short-circuit control current; The acquisition of the short-circuit voltage value includes: In one control cycle, DSP multi-channel is used to collect voltages m times, and the average value of the voltages is calculated to obtain the short-circuit voltage value; where m>1; The short-circuit stem extension change rate and the short-circuit stem extension acceleration are used to obtain the short-circuit control current using a fuzzy control method, including: If the short-circuit extension change rate is greater than zero, the current welding process is in the gun-pulling state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration; If the short-circuit extension change rate is zero and the short-circuit extension acceleration is zero, the current welding process is in a stable state, and the short-circuit control current is equal to the short-circuit current; If the short-circuit extension change rate is less than zero, the current welding process is in the gun pressing state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration; If the short-circuit extension change rate is greater than zero, the current welding process is in the gun-pulling state. According to the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration, the short-circuit control current is obtained, including: If the short-circuit extension change rate is greater than zero, and the short-circuit extension acceleration is greater than zero, the current welding process is in the accelerated gun pulling state, and the short-circuit control current is expressed as: I b =I a +(-20000)*△L n +(-200)*△△L n ; If the short-circuit extension change rate is greater than zero and the short-circuit extension acceleration is zero, the current welding process is in a uniform gun pulling state, and the short-circuit control current is expressed as: I b =I a +(-10000)*△L n +(-100)*△△L n ; If the short-circuit extension change rate is greater than zero and the short-circuit extension acceleration is less than zero, the current welding process is in the deceleration gun pulling state, and the short-circuit control current is expressed as: I b =I a +(-10000)*△L n +(-100)*△△L n ; Where, I a Indicates short-circuit current; △L n Indicates the rate of change of the stem extension at the nth short circuit; △△L n Indicates the nth short-circuit extension acceleration; If the short-circuit extension change rate is less than zero, the current welding process is in the gun pressing state, and the short-circuit control current is obtained according to the short-circuit current, the short-circuit extension change rate and the short-circuit extension acceleration, including: If the short-circuit extension change rate is less than zero and the short-circuit extension acceleration is greater than zero, the current welding process is in the accelerated gun pressure state, and the short-circuit control current is expressed as: I b =I a +(20000)*△L n +(200)*△△L n ; If the short-circuit extension change rate is less than zero and the short-circuit extension acceleration is zero, the current welding process is in a uniform speed gun pressing state, and the short-circuit control current is expressed as: I b =I a +(10000)*△L n +(100)*△△L n ; If the short-circuit extension change rate is less than zero, and the short-circuit extension acceleration is less than zero, the current welding process is in the deceleration gun pressure state, and the short-circuit control current is expressed as: I b =I a +(10000)*△L n +(100)*△△L n ; Where, I a Indicates short-circuit current; △L n Indicates the nth short circuit n Elongation change rate; △△L n Indicates the nth short-circuit extension acceleration; The short-circuit energy is expressed as: E n = I b 2 R n t; Where, I b Indicates the short-circuit control current, R n represents the nth short-circuit resistance; t represents the short-circuit time.

2. The short-circuit energy control method for gas metal arc welding according to claim 1, characterized in that: The short-circuit stem extension length is shown as: L n =f(R n ); R n =U n / I n ; Where, L n Indicates the nth short circuit extension length; R n represents the nth short-circuit resistance value; f(·) represents the relationship function between the stem extension length and the short-circuit resistance; U n Indicates the nth short-circuit voltage value; I n Indicates the nth short-circuit current value.

3. The short-circuit energy control method for gas metal arc welding according to claim 1, characterized in that: The short-circuit stem extension change rate and the short-circuit stem extension acceleration are expressed as: △△L n =△L n -△L n-1 ; △L n =L n -L n-1 ; Where, △△L n Indicates the nth short-circuit extension acceleration; △L n Indicates the rate of change of stem extension after the nth short circuit; △L n-1 Indicates the change rate of the stem extension at the n-1th short circuit; L n Indicates the nth short-circuit extension length; L n-1 Indicates the n-1th short-circuit extension length.

4. A control system based on the short-circuit energy control method of gas metal arc welding according to any one of claims 1 to 3, characterized in that: include: The data acquisition module is used to obtain the short-circuit current value and the short-circuit voltage value; A stem extension calculation module is used to calculate the short-circuit stem extension length using the short-circuit current value and the short-circuit voltage value; Calculating the short-circuit stem extension change rate and the short-circuit stem extension acceleration according to the short-circuit stem extension length; A short-circuit control current calculation module is used to: use the short-circuit current, the short-circuit stem extension change rate and the short-circuit stem extension acceleration to obtain the short-circuit control current using a fuzzy control method; The short-circuit energy calculation module is used to calculate the short-circuit energy according to the short-circuit control current.

5. A computer-readable storage medium having computer instructions stored thereon, characterized in that: When the computer instructions are executed by a processor, the steps of the short-circuit energy control method for gas metal arc welding according to any one of claims 1 to 3 are implemented.

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