A control method and device of a TIG-II multifunctional inverter welder based on a single-chip microcomputer

Abstract

The application discloses a TIG-II multifunctional inverter welding machine control method and device based on a single-chip microcomputer, and the control method comprises the following steps: converting input direct-current voltage into high-frequency alternating-current voltage and outputting the high-frequency alternating-current voltage to a main transformer of an inverter welding machine; controlling a pulse width modulation signal of a power module to adjust the size and waveform of output current; detecting output current of the inverter welding machine and converting the output current into an analog voltage signal to feed back to the single-chip microcomputer; converting digital signals output by the single-chip microcomputer into analog signals and inputting the analog signals to the power module; obtaining an error value according to an analog voltage signal fed back by a secondary feedback module and a preset target current value; obtaining an adjusted DA output signal through proportional and integral operation according to the error value; displaying the working state and parameters of the inverter welding machine; and setting the working mode and parameters of the inverter welding machine. The application can realize accurate control and multifunctional adjustment of the inverter welding machine and improve welding quality and efficiency.

Description

Technical Field

[0001] This invention relates to the field of inverter welding machine technology, and in particular to a control method and device for a TIG-II multi-functional inverter welding machine based on a single-chip microcomputer. Background Technology

[0002] An inverter welding machine is a device that uses a power module to convert the input DC voltage into a high-frequency AC voltage. This AC voltage is then passed through a transformer and rectifier before being output to the welding torch. An arc is generated between the tungsten electrode and the workpiece to perform the welding operation. Inverter welding machines have advantages such as small size, light weight, high efficiency, energy saving, and environmental friendliness, and are widely used in welding various metal materials.

[0003] TIG welding is a common process using inverter welding machines, also known as gas tungsten inert gas welding or argon arc welding. TIG welding utilizes a non-molten tungsten electrode and an inert gas (such as argon or helium) as a protective medium to generate a stable arc for welding operations. TIG welding can be used to weld non-ferrous metals that are difficult to weld, such as stainless steel, aluminum alloys, and magnesium alloys, as well as ferrous metals. TIG welding offers advantages such as high weld quality, a small heat-affected zone, minimal deformation, no spatter, and no porosity, but it also has disadvantages such as high operational difficulty, slow speed, and high cost.

[0004] To improve the performance and effect of TIG welding, the control system of the inverter welding machine needs to be optimized and improved. Existing microcontroller-based inverter welding machine control systems have the following drawbacks: 1) The adjustment accuracy of the pulse width modulation signal of the power module is not high enough, resulting in an unstable and uneven output current waveform; 2) The control algorithm used by the microcontroller cannot be optimized, leading to a large error between the output current and the set value; 3) The logic function control implemented by the microcontroller is not perfect or flexible enough, making the inverter welding machine unsuitable for different occasions and needs; 4) The communication method between the microcontroller and the display and button components is not simple and efficient enough, resulting in inconvenience for user operation. Therefore, a microcontroller-based TIG-II multifunctional inverter welding machine control method, device, and control mechanism are needed to solve the above problems. Summary of the Invention

[0005] The purpose of this application is to provide a TIG-II multi-functional inverter welding machine control method and device based on a single-chip microcomputer. In this solution, the inverter welding machine can be precisely controlled and multi-functionally adjusted, thereby improving welding quality and efficiency. It has the advantages of high efficiency, stability and adjustability.

[0006] To address the aforementioned technical problems, this application provides a microcontroller-based control method for the TIG-II multi-functional inverter welding machine, comprising:

[0007] The input DC voltage is converted into a high-frequency AC voltage and output to the main transformer of the inverter welding machine;

[0008] The pulse width modulation signal of the control power module is used to adjust the magnitude and waveform of the output current;

[0009] The output current of the inverter welding machine is detected, and the output current is converted into an analog voltage signal and fed back to the microcontroller.

[0010] The error value is obtained based on the analog voltage signal fed back by the secondary feedback module and the preset target current value;

[0011] Based on the error value, the adjusted DA output signal is obtained through proportional and integral calculations;

[0012] The DA output signal is converted into an analog signal and sent to the power supply module to adjust the pulse width modulation signal of the power supply module;

[0013] Displays the operating status and parameters of the inverter welding machine;

[0014] Set the operating mode and parameters of the inverter welding machine.

[0015] Preferably, setting the operating mode and parameters of the inverter welding machine includes:

[0016] The system obtains the user's first key input signal to control the corresponding working mode and select different output current waveforms and parameters.

[0017] Preferably, setting the operating mode and parameters of the inverter welding machine further includes:

[0018] The user's second button input signal is used to set the cold welding function switch and control the output current to switch between working time and interval time.

[0019] Preferably, setting the operating mode and parameters of the inverter welding machine further includes:

[0020] The system obtains the user's third key input signal to set the overheat protection function switch, detects the temperature of the inverter welding machine, and stops outputting current when the temperature exceeds the set value.

[0021] Preferably, setting the operating mode and parameters of the inverter welding machine further includes:

[0022] The system acquires the user's fourth key input signal to set the fault detection function switch, detects the input voltage, output current, and output voltage parameters of the inverter welding machine, and alarms and stops the output current when an abnormality occurs.

[0023] Preferably, the single-chip microcomputer-based TIG-II multi-functional inverter welding machine control method further includes:

[0024] Based on the storage function switch, the digital signal output by the microcontroller is stored in the storage chip;

[0025] Based on the function switch, the stored digital signal is read from the memory chip and input to the power module.

[0026] Preferably, the step of obtaining the user's first key input signal to control the corresponding working mode and selecting different output current waveforms and parameters includes:

[0027] The inverter welding machine has two working modes: TIG argon arc welding mode and MMA manual welding mode.

[0028] Preferably, detecting the output current of the inverter welding machine and converting the output current into an analog voltage signal to be fed back to the microcontroller includes:

[0029] The output current of the inverter welding machine is detected by a Hall sensor.

[0030] To address the aforementioned technical problems, this application provides a microcontroller-based TIG-II multi-functional inverter welding machine control device. A microcontroller-based TIG-II multi-functional inverter welding machine control method is applied to this device. The microcontroller-based TIG-II multi-functional inverter welding machine control device includes:

[0031] The power module is used to convert the input DC voltage into a high-frequency AC voltage and output it to the main transformer of the inverter welding machine.

[0032] A microcontroller is used to control the pulse width modulation signal of the power module to adjust the magnitude and waveform of the output current;

[0033] The secondary feedback module is used to detect the output current of the inverter welding machine and convert the output current into an analog voltage signal to feed back to the microcontroller;

[0034] The DA conversion module is used to convert the digital signal output by the microcontroller into an analog signal and input it to the power supply module;

[0035] The error calculation module is used to obtain the error value based on the analog voltage signal fed back by the secondary feedback module and the preset target current value;

[0036] The arithmetic module is used to obtain the adjusted DA output signal based on the error value through proportional and integral operations;

[0037] An adjustment module is used to convert the DA output signal into an analog signal and output it to the power supply module to adjust the pulse width modulation signal of the power supply module;

[0038] The display module is used to display the working status and parameters of the inverter welding machine;

[0039] The button module is used to set the working mode and parameters of the inverter welding machine.

[0040] Preferably, the power module has built-in overvoltage protection, overcurrent protection, undervoltage lockout, and soft-start protection mechanisms.

[0041] The TIG-II multi-functional inverter welding machine control method and device based on a microcontroller disclosed in this invention have the following beneficial effects. The method and device include: converting the input DC voltage into a high-frequency AC voltage and outputting it to the main transformer of the inverter welding machine; controlling the pulse width modulation signal of the power supply module to adjust the magnitude and waveform of the output current; detecting the output current of the inverter welding machine and converting it into an analog voltage signal to feed back to the microcontroller; obtaining an error value based on the analog voltage signal fed back by the secondary feedback module and a preset target current value; obtaining the adjusted DA output signal based on the error value through proportional and integral operations; converting the DA output signal into an analog signal and outputting it to the power supply module to adjust the pulse width modulation signal of the power supply module; displaying the working status and parameters of the inverter welding machine; and setting the working mode and parameters of the inverter welding machine. Therefore, this invention enables precise control and multi-functional adjustment of inverter welding machines, improving welding quality and efficiency. It employs a PI loop algorithm, which can quickly adjust the DA output signal based on real-time feedback and set values ​​of the output current, ensuring the stability and accuracy of the output current. Furthermore, this invention implements logic function control, allowing users to select different working modes and parameters according to their needs and operations, achieving functions such as cold welding, overheat protection, and fault detection, thereby improving welding safety and reliability. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort:

[0043] Figure 1 This is a flowchart illustrating a preferred embodiment of the TIG-II multi-functional inverter welding machine control method based on a microcontroller according to the present invention.

[0044] Figure 2 This is a flowchart illustrating the setting of the working mode and parameters of the TIG-II multi-functional inverter welding machine based on a microcontroller, according to a preferred embodiment of the present invention.

[0045] Figure 3 This is a schematic diagram of the structure of a TIG-II multi-functional inverter welding machine control device based on a single-chip microcomputer, according to a preferred embodiment of the present invention. Detailed Implementation

[0046] The core of this application is to provide a TIG-II multi-functional inverter welding machine control method and device based on a single-chip microcomputer. In this solution, precise control and multi-functional adjustment of the inverter welding machine can be achieved, thereby improving welding quality and efficiency. It has the advantages of high efficiency, stability and adjustability.

[0047] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0048] Please see Figure 1 , Figure 1 A flowchart illustrating a microcontroller-based TIG-II multi-functional inverter welding machine control method provided in this application includes:

[0049] S1. Converts the input DC voltage into a high-frequency AC voltage and outputs it to the main transformer of the inverter welding machine;

[0050] Specifically, the input DC voltage is converted into a high-frequency AC voltage through the power module and output to the main transformer of the inverter welding machine.

[0051] S2, control the pulse width modulation signal of the power supply module to adjust the magnitude and waveform of the output current;

[0052] Specifically, the power supply module is configured with a high-performance current-mode PWM controller, which converts the input DC voltage into a high-frequency AC voltage and outputs it to the main transformer. In this embodiment, the power supply module is designated as a power chip 3846. The COMP pin of the power supply module receives an analog signal from the DA converter to adjust its pulse width modulation signal, thereby regulating the magnitude and waveform of the output current. The microcontroller outputs a digital signal to set the operating frequency of the power supply module. In another preferred embodiment, the chip model of the power supply module is not specifically limited.

[0053] S3. Detect the output current of the inverter welding machine and convert the output current into an analog voltage signal to feed back to the microcontroller;

[0054] Specifically, in this embodiment, a microcontroller is used to implement various control functions of the inverter welding machine. The microcontroller outputs an 8-bit digital signal to the DA converter to adjust the pulse width modulation signal of the power supply module. In this embodiment, the microcontroller can be an AT89C51. In another preferred embodiment, the microcontroller can be an STM32 series microcontroller; no specific limitation is made here.

[0055] S4. Obtain the error value based on the analog voltage signal fed back by the secondary feedback module and the preset target current value;

[0056] Specifically, in this embodiment, the secondary feedback module is used to detect the output current of the inverter welding machine and convert it into an analog voltage signal, which is then fed back to the microcontroller. The secondary feedback module includes a voltage divider unit and an operational amplifier unit. The voltage divider unit reduces the DC voltage output from the secondary transformer to a suitable range and inputs it to the non-inverting input of the operational amplifier unit. Simultaneously, the voltage divider unit converts the set target current value into an analog voltage signal and inputs it to the inverting input of the operational amplifier unit. The operational amplifier unit is implemented using an operational amplifier. The operational amplifier compares the analog voltage signals at the two input terminals and outputs a corresponding analog voltage signal as an error value, which is then input to the microcontroller.

[0057] S5. Based on the error value, the adjusted DA output signal is obtained through proportional and integral calculations;

[0058] Specifically, the microcontroller uses a PI loop algorithm to calculate the error value based on the analog voltage signal fed back by the secondary feedback module and the set target current value, and then obtains the adjusted DA output signal through proportional and integral operations.

[0059] Specifically, in this embodiment, the PI loop algorithm uses a proportional coefficient of 0.5 and an integral coefficient of 0.01; the error value is limited by ±10V, which can quickly eliminate static errors, improve dynamic response speed, and effectively suppress the oscillation and distortion of the output current waveform.

[0060] S6. Convert the DA output signal into an analog signal and output it to the power supply module to adjust the pulse width modulation signal of the power supply module;

[0061] Specifically, in this embodiment, the application uses a DA converter DAC0808 to convert the signal. The DA converter DAC0808 is an 8-bit parallel input digital-to-analog converter that can convert the 8-bit digital signal output by the microcontroller into an analog signal and input it to the COMP pin of the power chip 3846 to adjust its pulse width modulation signal.

[0062] S7. Display the working status and parameters of the inverter welding machine;

[0063] Specifically, the microcontroller outputs a 4-bit digital signal, which is input to the display. The display chip inside the display controls the digital tube to display the working status and parameters of the inverter welding machine.

[0064] S8. Set the working mode and parameters of the inverter welding machine.

[0065] Specifically, the microcontroller receives a 4-bit digital signal from the button via pin P3, which is used to set the working mode and parameters of the inverter welding machine.

[0066] In summary, this invention provides a microcontroller-based control method for a TIG-II multi-functional inverter welding machine. The control method includes: converting the input DC voltage into a high-frequency AC voltage and outputting it to the main transformer of the inverter welding machine; controlling the pulse width modulation signal of the power supply module to adjust the magnitude and waveform of the output current; detecting the output current of the inverter welding machine and converting the output current into an analog voltage signal to feed back to the microcontroller; obtaining an error value based on the analog voltage signal fed back by the secondary feedback module and a preset target current value; obtaining the adjusted DA output signal based on the error value through proportional and integral operations; converting the DA output signal into an analog signal and outputting it to the power supply module to adjust the pulse width modulation signal of the power supply module; displaying the working status and parameters of the inverter welding machine; and setting the working mode and parameters of the inverter welding machine. Therefore, this invention enables precise control and multi-functional adjustment of inverter welding machines, improving welding quality and efficiency. It employs a PI loop algorithm, which can quickly adjust the DA output signal based on real-time feedback and set values ​​of the output current, ensuring the stability and accuracy of the output current. Furthermore, this invention implements logic function control, allowing users to select different working modes and parameters according to their needs and operations, achieving functions such as cold welding, overheat protection, and fault detection, thereby improving welding safety and reliability.

[0067] Based on the above embodiments:

[0068] Please refer to Figure 2 , Figure 2 This application provides a flowchart illustrating the process of setting the operating mode and parameters of the inverter welding machine.

[0069] In a preferred embodiment, setting the operating mode and parameters of the inverter welding machine includes:

[0070] S81: Obtain the user's first key input signal to control the corresponding working mode and select different output current waveforms and parameters;

[0071] In a preferred embodiment, setting the operating mode and parameters of the inverter welding machine further includes:

[0072] S82: Obtain the user's second button input signal to set the cold welding function switch and control the output current to switch between working time and interval time.

[0073] In a preferred embodiment, setting the operating mode and parameters of the inverter welding machine further includes:

[0074] S83. Obtain the user's third key input signal to set the overheat protection function switch, detect the temperature of the inverter welding machine, and stop the output current when it exceeds the set value;

[0075] In a preferred embodiment, setting the operating mode and parameters of the inverter welding machine further includes:

[0076] S84. Obtain the user's fourth key input signal to set the fault detection function switch, detect the input voltage, output current, and output voltage parameters of the inverter welding machine, and alarm and stop the output current when an abnormality occurs.

[0077] As a preferred embodiment, the single-chip microcomputer-based TIG-II multi-functional inverter welding machine control method further includes:

[0078] Based on the storage function switch, the digital signal output by the microcontroller is stored in the storage chip;

[0079] Based on the function switch, the stored digital signal is read from the memory chip and input to the power module.

[0080] In one preferred embodiment, obtaining the user's first key input signal to control the corresponding operating mode and selecting different output current waveforms and parameters includes:

[0081] The inverter welding machine has two working modes: TIG argon arc welding mode and MMA manual welding mode.

[0082] Specifically, in this embodiment, the user can switch the working mode of the inverter welding machine through the button component, which is not specifically limited here.

[0083] In a preferred embodiment, detecting the output current of the inverter welding machine and converting the output current into an analog voltage signal to be fed back to the microcontroller includes:

[0084] The output current of the inverter welding machine is detected by a Hall sensor.

[0085] This application also provides a microcontroller-based TIG-II multi-functional inverter welding machine control device, wherein a microcontroller-based TIG-II multi-functional inverter welding machine control method is applied in the device, and the microcontroller-based TIG-II multi-functional inverter welding machine control device includes:

[0086] Power module 1 is used to convert the input DC voltage into a high-frequency AC voltage and output it to the main transformer of the inverter welding machine;

[0087] The microcontroller 2 is used to control the pulse width modulation signal of the power supply module to adjust the magnitude and waveform of the output current;

[0088] Secondary feedback module 3 is used to detect the output current of the inverter welding machine and convert the output current into an analog voltage signal to feed back to the microcontroller;

[0089] The DA conversion module 4 is used to convert the digital signal output by the microcontroller into an analog signal and input it to the power supply module;

[0090] Error calculation module 5 is used to obtain the error value based on the analog voltage signal fed back by the secondary feedback module and the preset target current value;

[0091] The calculation module 6 is used to obtain the adjusted DA output signal based on the error value through proportional and integral calculations;

[0092] The adjustment module 7 is used to convert the DA output signal into an analog signal and output it to the power supply module to adjust the pulse width modulation signal of the power supply module.

[0093] Display module 8 is used to display the working status and parameters of the inverter welding machine;

[0094] The button module 9 is used to set the working mode and parameters of the inverter welding machine.

[0095] In one preferred embodiment, the power module has built-in overvoltage protection, overcurrent protection, undervoltage lockout, and soft-start protection mechanisms.

[0096] Therefore, this invention uses a microcontroller program to control the pulse width of the power chip and adjust the output current, achieving a highly efficient, stable, and adjustable inverter welding machine control system. This invention also implements logic function control through a microcontroller, improving the intelligence level and ease of use of the inverter welding machine. Furthermore, this invention implements a cold welding function through a microcontroller program, effectively preventing oxides generated during the welding process and improving welding quality. This invention has advantages such as simple structure, excellent performance, low cost, and ease of implementation, and is suitable for inverter welding machine control in various applications.

[0097] It should be noted that, in this specification, the terms "comprising," "including," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0098] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A control method for a TIG-II multi-functional inverter welding machine based on a microcontroller, characterized in that, include: The input DC voltage is converted into a high-frequency AC voltage and output to the main transformer of the inverter welding machine; The pulse width modulation signal of the control power module is used to adjust the magnitude and waveform of the output current; The output current of the inverter welding machine is detected, and the output current is converted into an analog voltage signal and fed back to the microcontroller. The error value is obtained based on the analog voltage signal fed back by the secondary feedback module and the preset target current value; Based on the error value, the adjusted DA output signal is obtained through proportional and integral calculations; The DA output signal is converted into an analog signal and sent to the power supply module to adjust the pulse width modulation signal of the power supply module; Displays the operating status and parameters of the inverter welding machine; Set the operating mode and parameters of the inverter welding machine.

2. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 1, characterized in that, The setting of the working mode and parameters of the inverter welding machine includes: The system obtains the user's first key input signal to control the corresponding working mode and select different output current waveforms and parameters.

3. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 1, characterized in that, The setting of the working mode and parameters of the inverter welding machine also includes: The user's second button input signal is used to set the cold welding function switch and control the output current to switch between working time and interval time.

4. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 1, characterized in that, The setting of the working mode and parameters of the inverter welding machine also includes: The system obtains the user's third key input signal to set the overheat protection function switch, detects the temperature of the inverter welding machine, and stops outputting current when the temperature exceeds the set value.

5. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 1, characterized in that, The setting of the working mode and parameters of the inverter welding machine also includes: The system acquires the user's fourth key input signal to set the fault detection function switch, detects the input voltage, output current, and output voltage parameters of the inverter welding machine, and alarms and stops the output current when an abnormality occurs.

6. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 1, characterized in that, The single-chip microcomputer-based TIG-II multi-functional inverter welding machine control method also includes: Based on the storage function switch, the digital signal output by the microcontroller is stored in the storage chip; Based on the function switch, the stored digital signal is read from the memory chip and input to the power module.

7. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 2, characterized in that, The process of obtaining the user's first key input signal to control the corresponding working mode and selecting different output current waveforms and parameters includes: The inverter welding machine has two working modes: TIG argon arc welding mode and MMA manual welding mode.

8. The TIG-II multi-functional inverter welding machine control method based on a single-chip microcomputer according to claim 1, characterized in that, The step of detecting the output current of the inverter welding machine and converting the output current into an analog voltage signal and feeding it back to the microcontroller includes: The output current of the inverter welding machine is detected by a Hall sensor.

9. A microcontroller-based TIG-II multi-functional inverter welding machine control device, employing the microcontroller-based TIG-II multi-functional inverter welding machine control method as described in any one of claims 1-8, characterized in that, The TIG-II multi-functional inverter welding machine control device based on a single-chip microcomputer includes: The power module is used to convert the input DC voltage into a high-frequency AC voltage and output it to the main transformer of the inverter welding machine. A microcontroller is used to control the pulse width modulation signal of the power module to adjust the magnitude and waveform of the output current; The secondary feedback module is used to detect the output current of the inverter welding machine and convert the output current into an analog voltage signal to feed back to the microcontroller; The DA conversion module is used to convert the digital signal output by the microcontroller into an analog signal; The error calculation module is used to obtain the error value based on the analog voltage signal fed back by the secondary feedback module and the preset target current value; The arithmetic module is used to obtain the adjusted DA output signal based on the error value through proportional and integral operations; An adjustment module is used to convert the DA output signal into an analog signal and output it to the power supply module to adjust the pulse width modulation signal of the power supply module; The display module is used to display the working status and parameters of the inverter welding machine; The button module is used to set the working mode and parameters of the inverter welding machine.

10. A TIG-II multi-functional inverter welding machine control device based on a single-chip microcomputer according to claim 9, characterized in that, The power module has built-in overvoltage protection, overcurrent protection, undervoltage lockout, and soft-start protection mechanisms.

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