Pulse welding control method and system

Abstract

The invention provides a pulse welding control method and system. The method comprises the steps that the sampling average value of output voltage of a single pulse period is collected; acquiring a peak current value of the next period based on the sampling average value and the voltage set value; according to a preset first corresponding relation between the peak current value and the base current value, the base current value of the next period is calculated based on the peak current value of the next period, and in the first corresponding relation, the larger the peak current value is, the larger the corresponding base current value is; according to a preset second corresponding relation between the peak current value and the pulse period length, the pulse period length of the next period is calculated based on the peak current value of the next period, and in the second corresponding relation, the larger the peak current value is, the smaller the corresponding pulse period length is. According to the method, the welding parameters in the pulse welding process are accurately controlled, stable control over the one-pulse one-drop transition mode is achieved, and the welding quality and efficiency are improved.

Description

Technical Field

[0001] The present application relates to the field of welding technology, and in particular to a pulse welding control method and system. Background Art

[0002] As an efficient and high-precision welding technology, pulse welding has been widely used in the field of industrial manufacturing. Among them, MIG (metal inert gas) pulse welding is widely used in the welding of various metal materials due to its advantages such as stable arc, high weld quality and small welding deformation. However, in the MIG pulse welding process, achieving stable droplet transfer and arc length control is the key difficulty to improve welding quality and efficiency.

[0003] Droplet transfer is a basic process in pulse welding, which directly affects the formation of welds and welding quality. In MIG pulse welding, there are three main ways of droplet transfer: one pulse multiple drops, one pulse one drop, and multiple pulses one drop. The one pulse multiple droplet transfer method refers to the formation of multiple droplets in one pulse cycle. In this method, the droplet size is small and the transition frequency is high, but it is difficult to control precisely. The multiple pulses one droplet transfer method refers to the formation of one droplet in multiple pulse cycles. In this method, the droplet size is large, the weld formation is inconsistent, the spatter is large, and it is difficult to be applied in practice. The one pulse one droplet transfer method refers to the formation of one droplet in one pulse cycle. In this method, the droplet transfer is stable and there is no spatter. Therefore, the one pulse one droplet transfer method is an ideal droplet transfer mode. However, to achieve the one pulse one droplet transfer method, it is necessary to accurately control the welding parameters during the pulse welding process.

[0004] It should be noted that the information disclosed in the above background technology section is only used to enhance the understanding of the background of the present application, and therefore may include information that does not constitute prior art known to ordinary technicians in the field. Summary of the invention

[0005] In response to the problems in the prior art, the purpose of this application is to provide a pulse welding control method and system to accurately control the welding parameters during the pulse welding process, achieve stable control of the one-pulse-one-drop transition mode, and improve welding quality and efficiency.

[0006] The first aspect of the present application provides a pulse welding control method, comprising the following steps:

[0007] Get the sampled average value of the output voltage in a single pulse cycle;

[0008] Based on the sampled average value and the voltage setting value, the peak current value of the next cycle is obtained;

[0009] According to a preset first correspondence between the peak current value and the base current value, the base current value of the next cycle is calculated based on the peak current value of the next cycle, wherein in the first correspondence, the larger the peak current value, the larger the corresponding base current value;

[0010] According to a preset second correspondence between the peak current value and the pulse cycle length, based on the peak current value of the next cycle, the pulse cycle length of the next cycle is calculated, wherein in the second correspondence, the larger the peak current value, the smaller the corresponding pulse cycle length;

[0011] The welding process of the next cycle is controlled according to the peak current value, base current value and pulse cycle length of the next cycle.

[0012] In some embodiments, obtaining a sampled average value of the output voltage in a single pulse cycle includes the following steps: at the beginning of the next cycle, obtaining multiple sampled values ​​of the output voltage in the single pulse cycle that just ended, and calculating the sampled average value based on the multiple sampled values.

[0013] In some embodiments, the first corresponding relationship is a first linear relationship between the peak current value and the base current value.

[0014] In some embodiments, the second corresponding relationship is a second linear relationship between the peak current value and the pulse period length.

[0015] In some embodiments, obtaining the peak current value of the next cycle based on the sampled average value and the voltage setting value includes the following steps:

[0016] Calculate the difference between the sampling average value and the voltage setting value as the error;

[0017] Based on the error, a proportional-integral control algorithm is used to obtain the peak current value of the next cycle.

[0018] In some embodiments, obtaining the peak current value of the next cycle based on the sampled average value and the voltage setting value includes the following steps:

[0019] Calculate the difference between the sampling average value and the voltage setting value as the error;

[0020] Based on the error, a proportional-integral control algorithm is used to obtain a first peak current value of the next cycle;

[0021] The first peak current value is limited based on a preset peak voltage range, the second peak current value of the next cycle is updated, and the second peak current value of the next cycle is used as the peak current value actually used in the next cycle.

[0022] In some embodiments, the preset peak voltage range includes a peak voltage value greater than or equal to a preset minimum peak current value;

[0023] Limiting the first peak current value based on a preset peak voltage range includes:

[0024] Determining whether the first peak current value is less than the minimum peak current value;

[0025] If yes, the minimum peak current value is used as the second peak current value of the next cycle;

[0026] If not, the first peak current value is used as the second peak current value of the next cycle.

[0027] In some embodiments, the first corresponding relationship is a first corresponding relationship between a preset second peak current value and a pulse cycle length; the second corresponding relationship is a second corresponding relationship between a preset first peak current value and a pulse cycle length.

[0028] In some embodiments, when controlling the welding process of the next cycle, the waveform change of the welding current is controlled based on an RC filtering algorithm.

[0029] A second aspect of the present application provides a pulse welding control system, which is applied to the pulse welding control method of the first aspect, and the system comprises:

[0030] The voltage sampling module is used to collect the sampling average value of the output voltage of a single pulse cycle;

[0031] A current acquisition module, used to acquire a peak current value of the next cycle based on a sampled average value and a voltage setting value; and calculate a base current value of the next cycle based on the peak current value of the next cycle according to a preset first correspondence between the peak current value and the base current value, wherein in the first correspondence, the larger the peak current value, the larger the corresponding base current value;

[0032] A cycle acquisition module, used for calculating the pulse cycle length of the next cycle based on the peak current value of the next cycle according to a preset second correspondence between the peak current value and the pulse cycle length, wherein in the second correspondence, the larger the peak current value, the smaller the corresponding pulse cycle length;

[0033] The welding control module is used to control the welding process of the next cycle according to the peak current value, base current value and pulse cycle length of the next cycle.

[0034] The pulse welding control method and system provided in this application have the following advantages:

[0035] By adopting the pulse welding method of the present application, the peak current value of the next cycle is obtained based on the sampled average value and voltage setting value of the output voltage of a single pulse cycle collected in real time, the sampled average value is used as the output voltage feedback value, and the voltage setting value is used as the reference value to obtain the peak current value of the next cycle, so that the output voltage average value in a pulse cycle can gradually approach the voltage setting value, so as to achieve precise control of the peak current value, and based on the peak current value of the next cycle, the corresponding base current value and pulse cycle length of the next cycle are obtained, so as to achieve precise control of the welding parameters of the next cycle, so that the next cycle can stably achieve a pulse-one-drop transition welding, in which only one droplet is generated during each pulse current period and transitions to the molten pool, so that the welding heat input and weld formation can be accurately controlled. After obtaining the peak current value, the pulse welding method directly uses the first corresponding relationship and the second corresponding relationship to obtain the base current value and the pulse cycle length, without using a complex calculation method to obtain the base current value and the pulse cycle length, and has a fast response speed, and can well adapt to the control mode of re-obtaining the welding parameters in the pulse cycle before the start of each pulse cycle, so as to achieve real-time and precise control of the welding parameters.

[0036] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Other features, objects and advantages of the present application will become more apparent by reading the detailed description of non-limiting embodiments made with reference to the following drawings.

[0038] Figure 1 is a flow chart of a pulse welding control method according to an embodiment of the present application;

[0039] Figure 2 It is a schematic diagram of the change trend of the peak current value, the base current value and the pulse current value of one embodiment of the present application;

[0040] Figure 3 is a schematic diagram of a pulse welding output current waveform according to an embodiment of the present application;

[0041] Figure 4 is a schematic diagram of a calculation process of a pulse welding control method according to an embodiment of the present application;

[0042] Figure 5 It is a structural block diagram of a pulse welding control system according to an embodiment of the present application. DETAILED DESCRIPTION

[0043] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this application will be comprehensive and complete and the concepts of the example embodiments will be fully conveyed to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted. Although "first" or "second" etc. are used in this specification to represent certain features, they are only used to represent the function and are not used as a limitation on the number and importance of specific features.

[0044] When pulse welding in the prior art adopts a one-pulse-one-drop transition method, the control of welding parameters is not precise enough, which may lead to problems such as unstable droplet size and poor welding effect during the welding process. Based on this, the present application provides a pulse welding control method to accurately control the welding parameters of each pulse cycle, improve the stability of the welding process, and enhance the welding effect. Among them, pulse welding refers to a welding method that realizes the welding process by periodically changing the welding current. During the pulse welding process, the current is not a constant value, but is composed of alternating peak current values ​​and base current values. This periodic current change can effectively control the welding heat input, making the welding process more stable and the weld quality higher. The welding parameters adjusted in the pulse welding control method proposed in the present application include the peak current value, base current value and pulse cycle length of each pulse cycle.

[0045] like Figure 1 As shown, an embodiment of the present application provides a pulse welding control method, comprising the following steps:

[0046] S100: Obtaining the sampled average value of the output voltage of a single pulse cycle;

[0047] In this embodiment, at the beginning of the next cycle, multiple sampling values ​​of the output voltage in the single pulse cycle that has just ended are obtained, and the sampling average value is calculated based on the multiple sampling values, that is, the sampling average value is the output voltage feedback value of the welding equipment in the previous pulse cycle, and the voltage sampling values ​​are accumulated in a single pulse cycle. After the pulse cycle ends, the accumulated value is divided by the number of accumulations to obtain the sampling average value;

[0048] S200: Obtaining a peak current value of the next cycle based on the sampled average value and the voltage setting value;

[0049] The peak current value refers to the maximum value reached by the current during the pulse cycle, which is mainly used to control the droplet transfer during the welding process; if the peak current value is too high, the droplet transfer will be too frequent, the droplet size will be too small, and it may cause droplet splashing, increasing the probability of welding defects; if the peak current value is too low, it is easy to form too large droplets, which is not conducive to the stable realization of the one-pulse-one-drop transfer mode;

[0050] This application uses the sampling average value as the output voltage feedback value of the welding equipment and the voltage setting value as the reference value to obtain the peak current value of the next cycle, so that the output voltage average value in one pulse cycle can gradually approach the voltage setting value to achieve accurate control of the peak current value;

[0051] The voltage setting value is a preset value, which can be determined comprehensively based on factors such as welding materials, welding wire diameter, and welding wire type. For example, for welding materials with higher melting points, the voltage setting value will be higher, and for materials with lower melting points, the voltage setting value will be lower. The larger the welding wire diameter, the higher the corresponding voltage setting value. The voltage setting value can be a better welding voltage value obtained based on existing welding experience, and can be adjusted according to actual scene requirements.

[0052] S300: Calculating a base current value of a next cycle based on a preset first correspondence between a peak current value and a base current value, based on a peak current value of a next cycle, wherein in the first correspondence, a larger peak current value corresponds to a larger base current value;

[0053] The base current value refers to the minimum current value in the pulse cycle, which is mainly used to maintain the stability of the arc and provide a basic current level between the peak current pulses so that the arc will not be extinguished; the base current can also preheat the welding pool to a certain extent, which helps to better transfer the droplet when the next peak current pulse arrives;

[0054] S400: Calculating the pulse cycle length of the next cycle based on the peak current value of the next cycle according to a preset second correspondence between the peak current value and the pulse cycle length, wherein in the second correspondence, the larger the peak current value, the smaller the corresponding pulse cycle length;

[0055] The pulse cycle is the alternating period of peak current and base current (transition frequency of pulse welding); the pulse cycle length refers to the time experienced by a complete pulse current cycle, including the peak current duration and the base current duration; the pulse cycle length determines the frequency of pulse welding and has an important influence on the heat input and droplet transition frequency during welding.

[0056] S500: Control the welding process of the next cycle according to the peak current value, base current value and pulse cycle length of the next cycle.

[0057] By adopting the pulse welding method of the present application, the peak current value of the next cycle is obtained based on the sampled average value of the output voltage of a single pulse cycle collected in real time and the voltage setting value, the sampled average value is used as the output voltage feedback value, and the voltage setting value is used as the reference value to obtain the peak current value of the next cycle, so that the output voltage average value within a pulse cycle can gradually approach the voltage setting value to achieve precise control of the peak current value, and based on the peak current value of the next cycle, the corresponding base current value and pulse cycle length of the next cycle are obtained to achieve precise control of the welding parameters of the next cycle, so that the next cycle can stably achieve one-pulse-one-drop transition welding. Under this transition mode, only one molten droplet is generated and transitions to the molten pool during each pulse current, so that the welding heat input and weld formation can be accurately controlled.

[0058] After obtaining the peak current value, the pulse welding method directly uses the first corresponding relationship and the second corresponding relationship to obtain the base current value and the pulse cycle length, without using a complex calculation method to obtain the base current value and the pulse cycle length. It has a fast response speed and can adapt well to the control mode of re-obtaining the welding parameters within the pulse cycle before the start of each pulse cycle, thereby realizing real-time and precise control of the welding parameters.

[0059] This pulse welding method makes the molten droplet form transition at the moment when the pulse peak current drops or at the beginning of the subsequent pulse base current time, realizing a stable molten droplet transition of one pulse and one droplet, which can not only improve the forming quality of the weld, but also reduce spatter and oxidation, and improve the welding quality. By optimizing the pulse welding parameters, it is beneficial to improve the anti-interference ability of the arc length, so that the arc length remains stable during the welding process, which can not only improve the stability of the welding current, but also reduce welding defects caused by arc length fluctuations and improve welding efficiency.

[0060] Figure 2 It is a schematic diagram of the change trend of the peak current value, the base current value and the pulse current value of an embodiment of the present application. Figure 2 The changing trends of the various values ​​and the numerical relationships between the various values ​​are only examples. Figure 2 The horizontal axis represents time, and the vertical axis represents the value change. Curve A1 represents the peak current value change trend curve, curve A2 represents the base current value change trend curve, and curve A3 represents the pulse cycle length change trend. Figure 3 Schematic diagram of a pulse welding output current waveform according to an embodiment of the present application. Figure 3 The horizontal axis represents time, and the vertical axis represents the output current of the welding equipment. The maximum current in each pulse cycle is the peak current value, the minimum current is the base current value, and the duration of a complete pulse cycle is the pulse cycle length.

[0061] Combination Figure 2 and Figure 3It can be seen that in the first corresponding relationship, the larger the peak current value, the larger the corresponding base current value, that is, the peak current value and the base current value change in the same direction. When the peak current value gradually increases, the corresponding base current value also gradually increases. Because in the second corresponding relationship, the larger the peak current value, the smaller the corresponding pulse cycle length, that is, the peak current value and the pulse cycle length change in opposite directions. When the peak current value increases, it means that the arc length decreases, so the pulse cycle length needs to be reduced. Specifically, when shortening the pulse cycle length, the output current waveform rise time remains unchanged, while the current waveform fall time is shortened.

[0062] In this embodiment, the first corresponding relationship is a first linear relationship between the peak current value and the base current value. When the first corresponding relationship is preset, I 基值 =a*I 峰值 +b relationship, I 基值 Indicates the base current value, I 峰值 Indicates the peak current value. The values ​​of coefficients a and b are calibration values, which can be set by the staff based on the welding experience under the pulse-droplet transfer mode. For example, in the calibration process, the existing pulse welding method is used for welding, and multiple groups (greater than or equal to 3 groups) of peak current values ​​and base current values ​​(I 峰值 , I 基值 ), a straight line fitting is performed based on the multiple sets of sampling data to determine the values ​​of coefficients a and b in the relationship, thereby completing the establishment of the first corresponding relationship.

[0063] Therefore, after the peak current value of the next cycle is obtained in step S200, the base current value of the next cycle can be directly calculated by performing linear operation through the relational expression of the first corresponding relationship. The calculation method is simple and convenient, and a base current value with good welding effect can be obtained. The first corresponding relationship in the present application is not limited to a linear relationship, and can also be a nonlinear structure. For example, I 基值 =a*I 峰值 2 +b I 峰值 +c, and the values ​​of coefficients a, b, and c in the relationship are determined by calibration, thereby completing the establishment of the first corresponding relationship.

[0064] In this embodiment, the second corresponding relationship is a second linear relationship between the peak current value and the pulse period length. When the second corresponding relationship is preset, T=m*I is established. 峰值 +n, T represents the pulse cycle length, I 峰值Indicates the peak current value. The coefficients m and n are calibration values, which can be set by the staff based on the welding experience under the pulse-droplet transfer mode. For example, in the calibration process, the existing pulse welding method is used for welding, and multiple groups (greater than or equal to 3 groups) of peak current values ​​and pulse cycle lengths (I 峰值 , T), perform straight line fitting based on these multiple sets of sampling data, determine the values ​​of coefficients m and n in the relationship, and thus complete the establishment of the second corresponding relationship.

[0065] Therefore, after obtaining the peak current value of the next cycle in step S200, the pulse period length of the next cycle can be directly calculated by performing linear operation through the relationship of the second corresponding relationship. The calculation method is simple and can obtain the pulse period length with good welding effect. The first corresponding relationship in the present application is not limited to a linear relationship, but can also be a nonlinear structure, such as pre-establishing T = m * I 峰值 2 +n I 峰值 +p, and the values ​​of coefficients m, n, and p in the relationship are determined by calibration, thereby completing the establishment of the second corresponding relationship.

[0066] In one embodiment, the step S200: obtaining the peak current value of the next cycle based on the sampled average value and the voltage setting value, comprises the following steps:

[0067] Calculate the difference between the sampling average value and the voltage setting value as the error;

[0068] Based on the error, a proportional integral control algorithm (PI algorithm) is used to obtain the peak current value of the next cycle.

[0069] In the PI algorithm, the sampling average value is used as the voltage feedback value U fb , the voltage setting value is used as the reference value U ref , calculate the difference U between the two fb -U ref As error e. Based on the error e(t) at time t, the proportional gain K p And the integral gain K i To calculate the output value u(t) of the PI algorithm at the output time t. In this embodiment, u(t) represents the peak current value of the next cycle. By setting a reasonable proportional gain, the response speed of the peak current value to the voltage difference can be controlled. By setting a reasonable integral gain, the steady-state error can be eliminated. In proportional-integral control, an initial value of the proportional gain and the integral gain can be set first, and the proportional gain and the integral gain can be gradually adjusted to appropriate values ​​by observing the response and steady-state error of the control process. In this implementation, the u(t) value obtained by the PI algorithm can be used as the peak current value used for actual control in the next cycle.

[0070] In another embodiment, after the peak current value of the next cycle is obtained by the PI algorithm, the peak current value is not directly used to control the next cycle, but the peak current value is limited before being used to control the next cycle. Here, the peak current value directly obtained by the PI algorithm is defined as the first peak current value, and the peak current value after limiting is defined as the second peak current value. Figure 4 FIG. 1 is a schematic diagram of the calculation process of the pulse welding control method according to an embodiment of the present application. Figure 4 As shown, the step S200: obtaining the peak current value of the next cycle based on the sampled average value and the voltage setting value, includes the following steps:

[0071] Calculate the difference between the sampling average value and the voltage setting value as the error e;

[0072] Based on the error, a proportional-integral control algorithm is used to obtain a first peak current value for the next cycle; the first peak current value can be calculated using a PI algorithm, that is, the u(t) value obtained by the PI algorithm is the first peak current value;

[0073] The first peak current value is limited based on a preset peak voltage range, the second peak current value of the next cycle is updated, and the second peak current value of the next cycle is used as the peak current value actually used in the next cycle.

[0074] In this embodiment, the preset peak voltage range includes a peak voltage value greater than or equal to a preset minimum peak current value, that is, limiting the first peak current value is limiting the first peak current value to a minimum value, specifically including:

[0075] Determining whether the first peak current value is less than the minimum peak current value;

[0076] If yes, the minimum peak current value is used as the second peak current value of the next cycle;

[0077] If not, the first peak current value is used as the second peak current value of the next cycle.

[0078] During pulse welding, if the peak current value is too small, the molten droplet will be too large, which will affect the welding effect. Therefore, by limiting the peak current value to a minimum value, it is possible to avoid the peak current value being too small, thereby effectively ensuring the welding quality.

[0079] The effect of limiting the first peak current value can be seen in Figure 2 The changing trend of the A1 curve. Figure 2 The trend A1 in the middle shows the change trend of the second peak current value after the limit. The dotted line part B shows the local change of the first peak current value. minIndicates the minimum peak current value. When the first peak current value is greater than the minimum peak current value, the first peak current value is equal to the second peak current value. When the first peak current value drops to less than the minimum peak current value, the second peak current value of this section is equal to the minimum peak current value through limiting, that is, Figure 2 The flat portion of the A1 curve until the first peak current value rises to be greater than the minimum peak current value, and then the second peak current value is equal to the first peak current value.

[0080] See also Figure 2 and Figure 4 , the first corresponding relationship is the first corresponding relationship between the preset second peak current value and the base current value. Therefore, the base current value corresponds to the peak current value after limiting. Figure 2 As shown, after the second peak current value is limited to a flat section equal to the minimum peak current value, the corresponding base current value is also a flat section. By limiting the peak current value to the minimum value, the minimum value limiting of the base current value is also achieved. By limiting the base current value to the minimum value, the smoothness of the droplet transfer can be avoided due to the base current value being too small.

[0081] See also Figure 2 and Figure 4 , the second corresponding relationship is the second corresponding relationship between the preset first peak current value and the pulse cycle length. Therefore, the pulse cycle length corresponds to the peak current value before limiting. When the peak current value is very small, it is necessary to shorten the arc, so the cycle is lengthened. By obtaining the pulse cycle length based on the peak current value before limiting, when the peak current value is very small, it is beneficial to obtain a longer pulse cycle length, so that the arc change response is faster. Figure 4 As shown, after the first peak current value is obtained by the PI algorithm, one path is limited to obtain the second peak current value, and then a linear operation is performed based on the first corresponding relationship to obtain the base current value, and the other path is not limited and a linear operation is performed directly based on the second corresponding relationship to obtain the pulse cycle length.

[0082] In this embodiment, when controlling the welding process of the next cycle, the waveform change of the welding current is controlled based on the RC filtering algorithm. The RC filtering circuit is mainly composed of a resistor and a capacitor, and can smooth the waveform change of the welding current. When the current waveform begins to rise, since the voltage across the capacitor cannot change suddenly, the capacitor begins to charge in the early stage of the current rise, so the capacitor voltage will gradually rise, making the rising edge of the current waveform after RC filtering become gentle. When the current waveform drops, the capacitor starts to discharge, making the falling process of the output current waveform also become gentle.

[0083] like Figure 5As shown, an embodiment of the present application provides a pulse welding control system, which is applied to the above-mentioned pulse welding control method, and the system includes:

[0084] The voltage sampling module M100 is used to collect the sampling average value of the output voltage of a single pulse cycle;

[0085] The current acquisition module M200 is used to obtain the peak current value of the next cycle based on the sampled average value and the voltage setting value; and calculate the base current value of the next cycle based on the peak current value of the next cycle according to a preset first correspondence between the peak current value and the base current value, wherein in the first correspondence, the larger the peak current value, the larger the corresponding base current value;

[0086] The cycle acquisition module M300 is used to calculate the pulse cycle length of the next cycle based on the peak current value of the next cycle according to the second corresponding relationship between the preset peak current value and the pulse cycle length, wherein in the second corresponding relationship, the larger the peak current value, the smaller the corresponding pulse cycle length;

[0087] The welding control module M400 is used to control the welding process of the next cycle according to the peak current value, base current value and pulse cycle length of the next cycle.

[0088] By adopting the pulse welding system, when the functions of each module are realized, each step of the above-mentioned pulse welding control method can be realized, and thus the technical effect of the above-mentioned pulse welding control method can also be achieved. The functions of each module in the pulse welding system can be realized by adopting the specific implementation methods of each step of the above-mentioned pulse welding control method, which will not be described in detail here.

[0089] The above content is a further detailed description of the present application in combination with specific preferred implementation methods, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, which should be deemed to fall within the scope of protection of the present application.

Claims

1. A pulse welding control method, characterized in that: The steps include: Get the sampled average value of the output voltage in a single pulse cycle; Based on the sampled average value and the voltage setting value, obtaining the peak current value of the next cycle; According to a preset first correspondence between the peak current value and the base current value, the base current value of the next cycle is calculated based on the peak current value of the next cycle, wherein in the first correspondence, the larger the peak current value, the larger the corresponding base current value; According to a preset second correspondence between the peak current value and the pulse cycle length, based on the peak current value of the next cycle, the pulse cycle length of the next cycle is calculated, wherein in the second correspondence, the larger the peak current value, the smaller the corresponding pulse cycle length; The welding process of the next cycle is controlled according to the peak current value, the base current value and the pulse cycle length of the next cycle.

2. The pulse welding control method according to claim 1, characterized in that: The method of obtaining the sampled average value of the output voltage of a single pulse period comprises the following steps: At the beginning of the next cycle, a plurality of sampling values ​​of the output voltage in the single pulse cycle that has just ended are obtained, and a sampling average value is calculated based on the plurality of sampling values.

3. The pulse welding control method according to claim 1, characterized in that: The first corresponding relationship is a first linear relationship between the peak current value and the base current value.

4. The pulse welding control method according to claim 1, characterized in that: The second corresponding relationship is a second linear relationship between the peak current value and the pulse cycle length.

5. The pulse welding control method according to claim 1, characterized in that: Based on the sampled average value and the voltage setting value, the peak current value of the next cycle is obtained, comprising the following steps: Calculate the difference between the sampled average value and the voltage setting value as an error; Based on the error, a proportional-integral control algorithm is adopted to obtain the peak current value of the next cycle.

6. The pulse welding control method according to claim 1, characterized in that: Based on the sampled average value and the voltage setting value, the peak current value of the next cycle is obtained, comprising the following steps: Calculate the difference between the sampled average value and the voltage setting value as an error; Based on the error, a proportional-integral control algorithm is used to obtain a first peak current value of the next cycle; The first peak current value is limited based on a preset peak voltage range, the second peak current value of the next cycle is updated, and the second peak current value of the next cycle is used as the peak current value actually used in the next cycle.

7. The pulse welding control method according to claim 6, characterized in that: The preset peak voltage range includes a peak voltage value greater than or equal to a preset minimum peak current value; The limiting the first peak current value based on a preset peak voltage range includes: Determining whether the first peak current value is less than the minimum peak current value; If yes, taking the minimum peak current value as the second peak current value of the next cycle; If not, the first peak current value is used as the second peak current value of the next cycle.

8. The pulse welding control method according to claim 7, characterized in that: The first corresponding relationship is a first corresponding relationship between a preset second peak current value and a pulse cycle length; The second corresponding relationship is a second corresponding relationship between a preset first peak current value and a pulse cycle length.

9. The pulse welding control method according to claim 1, characterized in that: When controlling the welding process of the next cycle, the waveform change of the welding current is controlled based on the RC filtering algorithm.

10. A pulse welding control system, characterized in that: The pulse welding control method applied to any one of claims 1 to 9, wherein the system comprises: The voltage sampling module is used to collect the sampling average value of the output voltage of a single pulse cycle; A current acquisition module, configured to acquire a peak current value of a next cycle based on the sampled average value and the voltage setting value; and calculate a base current value of a next cycle based on the peak current value of the next cycle according to a preset first correspondence between the peak current value and the base current value, wherein in the first correspondence, the larger the peak current value, the larger the corresponding base current value; A cycle acquisition module, configured to calculate the pulse cycle length of the next cycle based on the peak current value of the next cycle according to a preset second correspondence between the peak current value and the pulse cycle length, wherein in the second correspondence, the larger the peak current value, the smaller the corresponding pulse cycle length; The welding control module is used to control the welding process of the next cycle according to the peak current value, base current value and pulse cycle length of the next cycle.

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