Welding control method and system for preventing adhesion of tungsten electrode

Abstract

The invention belongs to the technical field of welding automation control, and provides a tungsten electrode anti-adhesion welding control method and system, and the method comprises the steps: obtaining arc voltage data in a welding process; performing wavelet transformation on the voltage data to obtain a voltage sampling value after wavelet transformation; determining a relative deviation ratio, a voltage fluctuation ratio and a voltage jump frequency of the voltage according to the voltage sampling value; according to the relative deviation ratio of the voltage, the voltage fluctuation ratio and the voltage abrupt change frequency, an adhesion risk value is obtained in a weighted summation mode; and according to comparison of the adhesion risk value and the relative deviation ratio of the voltage with corresponding preset values, the alarm grade is determined, and whether the welding gun is controlled to be lifted or shut down is determined. Comprehensive monitoring of adhesion in the welding process is achieved, tungsten electrode adhesion is prevented, welding conditions are adjusted in real time through an alarm mechanism and a closed-loop control mechanism, and the problem that adhesion affects welding quality is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of welding automation control, and in particular relates to a tungsten electrode anti-adhesion welding control method and system. Background Art

[0002] In welding operations, especially TIG (Tungsten Inert Gas) welding, adhesion between the tungsten electrode and the workpiece is a key factor affecting welding quality and efficiency. Adhesion not only causes weld defects such as discontinuous welds and uneven surfaces, but can also damage the tungsten electrode, increasing production costs.

[0003] At present, the focus of the welding process is on the research on the optimization of welding parameters. There is no effective comprehensive monitoring of welding and prevention of tungsten electrode adhesion. In particular, there is a lack of technical solutions to adjust welding conditions in real time through alarm mechanisms and closed-loop control mechanisms to avoid adhesion affecting welding quality. Summary of the Invention

[0004] In order to solve the above problems, the present invention proposes a tungsten electrode anti-sticking welding control method and system. The present invention realizes comprehensive monitoring of adhesion during welding and prevents the occurrence of tungsten electrode adhesion. The welding conditions are adjusted in real time through an alarm mechanism and a closed-loop control mechanism, thereby solving the problem of adhesion affecting welding quality.

[0005] In order to achieve the above object, the present invention is implemented through the following technical solutions: In a first aspect, the present invention provides a tungsten electrode anti-sticking welding control method, comprising: Obtain arc voltage data during welding; Perform wavelet transform on the voltage data to obtain voltage sampling values ​​after wavelet transform; According to the voltage sampling value, determine the voltage relative deviation rate, voltage fluctuation ratio and voltage mutation frequency; The adhesion risk value is obtained by weighted summation based on the relative voltage deviation rate, voltage fluctuation ratio, and voltage mutation frequency. Based on the comparison between the adhesion risk value and the relative deviation rate of the voltage and the corresponding preset value, the alarm level is determined, and whether the welding gun is raised or shut down is determined.

[0006] Furthermore, the wavelet transform formula of the voltage signal can be expressed as: ; in, It is a voltage signal, which indicates the change of arc voltage over time during welding; is the wavelet basis function; is the scale parameter; is a positional parameter; is the wavelet transform result.

[0007] Furthermore, the relative deviation rate of voltage is: ; in, is the voltage sampling value obtained after wavelet transform; is the preset reference voltage value, is the relative deviation rate.

[0008] Furthermore, the voltage fluctuation ratio is equal to the ratio of the voltage fluctuation amplitude to the peak value of the voltage signal; the voltage fluctuation amplitude is the difference between the peak value and the valley value of the voltage signal; the voltage mutation frequency is the number of voltage mutations per unit time, and the basis for judging the mutation is that the voltage change exceeds a preset threshold.

[0009] Furthermore, the adhesion risk value is: ; in, 、 and It is the weight coefficient, and the exact value can be determined through multiple tests after powering on.

[0010] Furthermore, when the adhesion risk of the comprehensive judgment model is greater than a preset value and the relative deviation rate is greater than a first preset percentage, it indicates that there is a slight adhesion risk. At this time, a level 1 alarm is issued and the welding gun lifting control is started; When the adhesion risk of the comprehensive judgment model is greater than the preset value and the relative deviation rate is greater than the second preset percentage, it indicates that there is a serious adhesion risk. At this time, a second-level alarm is issued, triggering a shutdown and recording fault data; When the adhesion risk of the comprehensive judgment model is greater than the preset value, and the relative deviation rate exceeds the first preset percentage for a preset number of sampling cycles, the machine is shut down for inspection.

[0011] Furthermore, when the welding gun is lifted, the relative deviation rate Dynamic adjustment of welding gun height , for voltage deviation rate Integrate and the welding gun lifting control is: ; in, is the current height of the welding gun; is the base height of the welding gun; is the arc voltage deviation rate; is the proportionality coefficient; is the integral control coefficient; is the differential control coefficient.

[0012] In a second aspect, the present invention further provides a tungsten electrode anti-sticking welding control system, comprising: The data acquisition module is configured to: acquire arc voltage data during the welding process; The data processing module is configured to: perform wavelet transform on the voltage data to obtain voltage sampling values ​​after wavelet transform; The parameter determination module is configured to: determine the relative deviation rate of voltage, the voltage fluctuation ratio and the voltage mutation frequency according to the voltage sampling value; The comprehensive evaluation module is configured to obtain the adhesion risk value through weighted summation based on the relative voltage deviation rate, voltage fluctuation ratio, and voltage mutation frequency. The control module is configured to determine the alarm level and whether to control the welding gun to lift or shut down based on the comparison between the adhesion risk value and the relative deviation rate of the voltage and the corresponding preset value.

[0013] In a third aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the tungsten electrode anti-sticking welding control method described in the first aspect.

[0014] In a fourth aspect, the present invention also provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, wherein when the processor executes the program, the steps of the tungsten electrode anti-adhesion welding control method described in the first aspect are implemented.

[0015] In a fifth aspect, the present invention further provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of the tungsten electrode anti-sticking welding control method described in the first aspect are implemented.

[0016] Compared with the prior art, the present invention has the following beneficial effects: The present invention first determines the relative deviation rate of voltage, the voltage fluctuation ratio and the voltage mutation frequency based on the voltage sampling value; then, according to the relative deviation rate of voltage, the voltage fluctuation ratio and the voltage mutation frequency, obtains the adhesion risk value by weighted summation; finally, according to the adhesion risk value and the relative deviation rate of voltage, the alarm level is determined and whether the welding gun is to be raised or shut down is determined based on the comparison with the corresponding preset value; comprehensive monitoring of adhesion during the welding process and prevention of tungsten electrode adhesion are achieved, and the welding conditions are adjusted in real time through the alarm mechanism and the closed-loop control mechanism, thereby solving the problem of adhesion affecting the welding quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the specification of this embodiment are used to provide a further understanding of this embodiment. The schematic embodiments and descriptions of this embodiment are used to explain this embodiment and do not constitute an improper limitation on this embodiment.

[0018] Figure 1 This is a flow chart of the method of Example 1 of the present invention; Figure 2 This is a welding effect diagram of welding adhesion occurring in Example 1 of the present invention; Figure 3 This is a diagram showing the local welding effect after anti-adhesion welding control is performed according to Example 1 of the present invention; Figure 4 This is a diagram of the overall welding effect after anti-adhesion welding control is performed in Example 1 of the present invention. DETAILED DESCRIPTION

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0020] It should be noted that the following detailed descriptions are exemplary and are intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art to which the present application belongs.

[0021] Example 1: In order to solve the problem of detection and closed-loop prevention of tungsten electrode welding adhesion, such as Figure 1 As shown, this embodiment provides a tungsten electrode anti-adhesion welding control method. First, the arc voltage data during the welding process is obtained; the voltage data is subjected to wavelet transform to obtain the voltage sampling value after the wavelet transform; and based on the voltage sampling value, the relative deviation rate of the voltage, the voltage fluctuation ratio and the voltage mutation frequency are determined; then, based on the relative deviation rate of the voltage, the voltage fluctuation ratio and the voltage mutation frequency, the adhesion risk value is obtained by weighted summation; finally, based on the adhesion risk value and the relative deviation rate of the voltage, and the comparison with the corresponding preset value, the alarm level is determined, and it is determined whether the welding gun is lifted or shut down. Comprehensive monitoring of adhesion during welding is achieved, and the occurrence of tungsten electrode adhesion is prevented. The welding conditions are adjusted in real time through the alarm mechanism and the closed-loop control mechanism, solving the problem of adhesion affecting welding quality. The specific contents of the method of this embodiment are as follows: S1. Data collection: Real-time acquisition of arc voltage data during welding. Optionally, a high-frequency sampling circuit (linearity 0.1%, response time 40us, frequency range 0-20kHz) is used to obtain arc voltage data.

[0022] S2. Data processing: By performing wavelet transform on the voltage, the influence of noise generated during data acquisition on the acquisition results can be reduced. The wavelet transform formula of the voltage signal can be expressed as: ; in, It is a voltage signal, which represents the change of arc voltage over time during the welding process. It is a non-stationary signal containing noise. As the wavelet basis function, Daubechies wavelet is selected (which has compact support and orthogonality and is suitable for removing noise). and location Wavelet basis functions can match different frequency and time characteristics of voltage signals; is the scale parameter, which controls the expansion and contraction of the wavelet basis function; when When it is larger, the wavelet basis function is stretched and used to analyze low-frequency features; when When it is small, the wavelet basis function is compressed and used to analyze high-frequency features; is the position parameter, which controls the translation of the wavelet basis function and is used to analyze the characteristics of the voltage signal at different time positions; is the wavelet transform result, which indicates that the voltage signal is in scale and location By analyzing the local characteristics of , the key information of the voltage signal can be extracted, such as the mutation point, fluctuation amplitude, etc.

[0023] in, In order to remove the noise from the arc voltage, a threshold can be set based on the maximum and minimum voltage values ​​measured after the subsequent startup. When the voltage is not within this threshold (18-20V), it will be discarded.

[0024] S3. Control process: S3.1. Initialization before arc starting: The initial distance between the tungsten electrode tip and the workpiece surface is determined by a contact sensor (the welding gun automatically descends after pressing the start button and automatically rises the required distance after the tungsten electrode touches the workpiece) H 1 (recommended range 3-5mm).

[0025] Setting the arc voltage reference value U 1: After the arc is stabilized within the preset time (≥1s), the maximum arc voltage is collected as the initial reference.

[0026] S3.3 Real-time monitoring and adhesion determination: Dynamic voltage deviation calculation: ; in, is the voltage sampling value obtained after wavelet transform; is the preset reference voltage value, is the relative deviation rate.

[0027] S3.4. Calculate the voltage fluctuation amplitude and fluctuation ratio: The voltage fluctuation amplitude is the difference between the peak value and the valley value of the voltage signal; the fluctuation ratio is equal to the ratio of the voltage fluctuation amplitude to the peak value of the voltage signal.

[0028] S3.4. Calculate the voltage mutation frequency: The voltage mutation frequency is the number of voltage mutations per unit time. The basis for judging the mutation is that the voltage change exceeds a certain threshold.

[0029] S3.5. Establish a comprehensive judgment model: Multiple voltage features are integrated into adhesion judgment to build a weighted comprehensive judgment model: ; in, 、 and is the weight coefficient, and its accurate value can be determined through multiple tests after power-on; the voltage mutation frequency is the number of voltage mutations per unit time, and is a dimensionless value.

[0030] S3.6, Alarm level classification: When the adhesion risk of the comprehensive judgment model is greater than the preset value, and the relative deviation rate is greater than the first preset percentage ( ≥50%), it indicates that there is a slight risk of adhesion. At this time, a level 1 alarm is issued and the welding gun lifting control is started.

[0031] When the adhesion risk of the comprehensive judgment model is greater than the preset value, and the relative deviation rate is greater than the second preset percentage ( ≥75%), it indicates that there is a serious risk of adhesion. At this time, a secondary alarm is issued, triggering a shutdown and recording fault data.

[0032] Alternatively, when the adhesion risk of the comprehensive judgment model is greater than the preset value and the relative deviation rate ΔU exceeds 50% for five consecutive sampling cycles, the machine is shut down for inspection.

[0033] The first preset percentage is smaller than the second preset percentage.

[0034] S3.7, Closed-loop control strategy: When controlling the welding gun lifting, according to the relative deviation rate Dynamic adjustment of welding gun height , for voltage deviation rate Integrate to eliminate steady-state error, and calculate the voltage deviation rate (i.e. derivatives of ), predict the future behavior of the system and adjust it in advance.

[0035] ; in, is the current height of the welding gun; is the base height of the welding gun; is the arc voltage deviation rate; is the proportionality coefficient (empirical value 0.05-0.2%); is the integral control coefficient (the empirical value is 0.05-0.1%); is the differential control coefficient (the empirical value is 0.05-0.2%), and the response speed is optimized through the PID algorithm.

[0036] S3.8, Self-protection mechanism: When the relative deviation rate is greater than the third preset percentage (ΔU ≥ 80%), or the current height of the welding gun after adjustment Exceeding the safety threshold ( H 1±3mm), forced shutdown.

[0037] The optional tungsten electrode distance adjustment mechanism includes a servo motor-driven Z-axis lift with an adjustment accuracy of ±0.2mm and a response time of ≤60ms. The control unit is a Programmable Logic Controller (PLC), which includes an arc voltage data signal receiver, an anti-tungsten electrode sticking control algorithm, and an actuator closed-loop control program. The PLC can be used to output alarms and control the actuator to adjust the welding torch or perform an emergency shutdown.

[0038] like Figure 2 、 Figure 3 and Figure 4 As shown, this embodiment reduces molten pool disturbance by dynamically adjusting the tungsten electrode distance, resulting in improved weld consistency and a lower incidence of sticking accidents. Furthermore, this embodiment supports integration with robotic welding systems and is compatible with all tungsten inert gas arc welding machine models.

[0039] Example 2: This embodiment provides a tungsten electrode anti-sticking welding control system, including: The data acquisition module is configured to: acquire arc voltage data during the welding process; The data processing module is configured to: perform wavelet transform on the voltage data to obtain voltage sampling values ​​after wavelet transform; The parameter determination module is configured to: determine the relative deviation rate of voltage, the voltage fluctuation ratio and the voltage mutation frequency according to the voltage sampling value; The comprehensive evaluation module is configured to obtain the adhesion risk value through weighted summation based on the relative voltage deviation rate, voltage fluctuation ratio, and voltage mutation frequency. The control module is configured to determine the alarm level and whether to control the welding gun to lift or shut down based on the comparison between the adhesion risk value and the relative deviation rate of the voltage and the corresponding preset value.

[0040] The working method of the system is the same as the tungsten electrode anti-sticking welding control method in Example 1, and will not be repeated here.

[0041] Example 3: This embodiment provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the steps of the tungsten electrode anti-sticking welding control method described in Example 1 are implemented.

[0042] Example 4: This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and capable of running on the processor. When the processor executes the program, the steps of the tungsten electrode anti-sticking welding control method described in Example 1 are implemented.

[0043] Example 5: This embodiment provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the steps of the tungsten electrode anti-sticking welding control method described in Example 1 are implemented.

[0044] The above description is merely a preferred embodiment of this embodiment and is not intended to limit this embodiment. Those skilled in the art will readily appreciate that this embodiment may be modified and varied in various ways. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this embodiment shall be within the scope of protection of this embodiment.

Claims

1. A tungsten electrode anti-sticking welding control method, characterized in that: include: Obtain arc voltage data during welding; Perform wavelet transform on the voltage data to obtain voltage sampling values ​​after wavelet transform; According to the voltage sampling value, determine the voltage relative deviation rate, voltage fluctuation ratio and voltage mutation frequency; The adhesion risk value is obtained by weighted summation based on the relative voltage deviation rate, voltage fluctuation ratio, and voltage mutation frequency. Based on the comparison between the adhesion risk value and the relative deviation rate of the voltage and the corresponding preset value, the alarm level is determined, and whether the welding gun is raised or shut down is determined.

2. A tungsten electrode anti-sticking welding control method according to claim 1, characterized in that: The wavelet transform formula of voltage signal can be expressed as: ； in, It is a voltage signal, which indicates the change of arc voltage over time during welding; is the wavelet basis function; is the scale parameter; is a positional parameter; is the wavelet transform result.

3. A tungsten electrode anti-sticking welding control method according to claim 1, characterized in that: The relative deviation rate of voltage is: ； in, is the voltage sampling value obtained after wavelet transform; is the preset reference voltage value, is the relative deviation rate.

4. A tungsten electrode anti-sticking welding control method as claimed in claim 3, characterized in that: The voltage fluctuation ratio is equal to the ratio of the voltage fluctuation amplitude to the peak value of the voltage signal; the voltage fluctuation amplitude is the difference between the peak value and the valley value of the voltage signal; the voltage mutation frequency is the number of voltage mutations per unit time, and the basis for judging the mutation is that the voltage change exceeds the preset threshold.

5. A tungsten electrode anti-sticking welding control method according to claim 4, characterized in that: The adhesion risk value is: ； in, 、 and It is the weight coefficient, and the exact value can be determined through multiple tests after powering on.

6. A tungsten electrode anti-sticking welding control method according to claim 1, characterized in that: When the adhesion risk of the comprehensive judgment model is greater than the preset value and the relative deviation rate is greater than the first preset percentage, it indicates that there is a slight adhesion risk. At this time, a level 1 alarm is issued and the welding gun lifting control is started; When the adhesion risk of the comprehensive judgment model is greater than the preset value and the relative deviation rate is greater than the second preset percentage, it indicates that there is a serious adhesion risk. At this time, a second-level alarm is issued, triggering a shutdown and recording fault data; When the adhesion risk of the comprehensive judgment model is greater than the preset value, and the relative deviation rate exceeds the first preset percentage for a preset number of sampling cycles, the machine is shut down for inspection.

7. The tungsten electrode anti-sticking welding control method according to claim 1, characterized in that: When controlling the welding gun lifting, according to the relative deviation rate Dynamic adjustment of welding gun height , for voltage deviation rate Integrate and the welding gun lifting control is: ； in, is the current height of the welding gun; is the base height of the welding gun; is the arc voltage deviation rate; is the proportionality coefficient; is the integral control coefficient; is the differential control coefficient.

8. A tungsten electrode anti-sticking welding control system, characterized in that: include: The data acquisition module is configured to: acquire arc voltage data during the welding process; The data processing module is configured to: perform wavelet transform on the voltage data to obtain voltage sampling values ​​after wavelet transform; The parameter determination module is configured to: determine the relative deviation rate of voltage, the voltage fluctuation ratio and the voltage mutation frequency according to the voltage sampling value; The comprehensive evaluation module is configured to obtain the adhesion risk value through weighted summation based on the relative voltage deviation rate, voltage fluctuation ratio, and voltage mutation frequency. The control module is configured to determine the alarm level and whether to control the welding gun to lift or shut down based on the comparison between the adhesion risk value and the relative deviation rate of the voltage and the corresponding preset value.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and capable of running on the processor, characterized in that: When the processor executes the program, the steps of the tungsten electrode anti-sticking welding control method according to any one of claims 1 to 7 are implemented.

10. A computer program product, characterized in that The computer program product includes a computer program, and when the computer program is executed by a processor, the steps of the tungsten electrode anti-sticking welding control method according to any one of claims 1 to 7 are implemented.

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