Low-interference high-frequency high-voltage arc striking device for argon tungsten-arc welding

Abstract

The invention discloses a low-interference high-frequency high-voltage arc striking device for argon tungsten-arc welding, and belongs to the technical field of electric arc welding. Comprising a soft-switching zero-voltage oscillating circuit, a spark gap oscillating circuit and a welding machine main circuit coupling. The soft switching circuit is composed of an inductor L1, field-effect tubes Q1 / Q2, resonant capacitors C1 / C2 and a high-voltage pack T1, zero voltage switching ZVS is achieved through push-pull self-excitation quasi-resonance, and electromagnetic interference is reduced. The spark gap circuit is composed of a T1 secondary side, a capacitor C3 and a spark gap HF, and RLC damped oscillation is formed; and the coupling inductor T2 accesses a boost signal to a main circuit of the welding machine to complete non-contact arc striking. A conducted interference test platform verifies that the interference peak values at the welding no-load moment and the arc starting moment are reduced by 12.61 dB (23.4%) and 9.52 dB (33.4%) respectively, and the interference peak values are obviously superior to those of a traditional scheme and FennisiWave230. The system supports a plurality of energy input modes (a main transformer, a power frequency rectifier or a battery), and has the characteristics of low interference and high reliability.

Description

Technical Field

[0001] The invention relates to the technical field of arc welding, in particular to a high-frequency and high-voltage arc starting device with low interference for tungsten inert gas arc welding. Background Art

[0002] Tungsten inert gas welding, also known as TIG welding, is an arc welding method that generates heat between the non-consumable tungsten electrode and the workpiece. It is often used for welding non-ferrous metals, such as aluminum alloys, magnesium alloys, copper alloys, etc. Therefore, as a high-precision welding process, it is widely used in aerospace, nuclear industry and other fields.

[0003] Tungsten inert gas welding usually uses two methods: contact arc starting and non-contact arc starting. However, since contact arc starting can easily cause tungsten to be clamped in the workpiece, non-contact arc starting is used in practice. Non-contact arc starting generally uses high frequency and high voltage, but this method often brings huge conduction interference to the power grid, causing the equipment in the power grid to not work properly or damage the equipment. Therefore, it is of great practical significance to study new arc starting circuits and reduce conduction interference.

[0004] There are many studies on arc starting related to tungsten inert gas welding. Li Liangyu et al. summarized and analyzed contact arc starting and non-contact arc starting in 1995. For non-contact arc starting, there are high-frequency high-voltage and high-voltage pulse methods, which are harmful to welders and equipment, indicating that the arc starting process is related to the electrode material and type, shielding gas, the gap between the tungsten electrode and the workpiece, and the external characteristics of the power supply. In 1997, Shao Chengji et al. gave different non-contact arc starting methods, such as double tungsten electrode high-frequency high-voltage arc starting, inverter vacuum arrester arc starter, double frequency high-voltage pulse arc starter, piezoelectric crystal arc starter, thyristor high-voltage pulse arc starter, etc. Shi Linan et al. conducted relevant mechanism analysis on the arc starting process of tungsten inert gas welding and MIG welding, and proposed a new method of laser-assisted tungsten inert gas welding arc starting. The patent "Arc Starting Method for Automated Welding System" Publication No. CN109648174B proposes an arc starting method for automated welding, which is essentially an automated realization of contact arc starting. In addition, in "Arc welding equipment Part 10: Electromagnetic compatibility (EMC) requirements"

[0005] In GB / T15579.10-2020, the standard specifies the requirements and test methods for electric welding machines during normal operation, but there is no clear definition for the arc striking process. These studies have the following shortcomings:

[0006] 1) Only different arc striking methods or mechanism analysis are proposed, but no quantitative research on the arc striking process's interference with power grid conduction is conducted;

[0007] 2) The current non-contact arc striking method causes great interference to the power grid conduction and is extremely harmful. Summary of the invention

[0008] The purpose of the present invention is to provide a high-frequency and high-voltage arc-starting device with low interference for tungsten inert gas arc welding. By testing and comparing the proposed zero-voltage arc-starting device with similar domestic and foreign Fronius products on the market, it is confirmed that the newly proposed arc-starting device can effectively reduce the conducted interference to the power grid under two working conditions: no-load welding (arc-starting circuit works but no arcing) and arc-starting moment.

[0009] To achieve the above object, the present invention provides a low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding, comprising the following circuits:

[0010] Soft switching zero voltage oscillation circuit, composed of inductor L 1 , Field Effect Transistor Q 1 , Field Effect Transistor Q 2 , resonant capacitor C 1 , resonant capacitor C 2 And high voltage package T 1 Composition: input 12V DC power supply, generate high-frequency AC signal through push-pull self-excited quasi-resonance;

[0011] Spark gap oscillation circuit: composed of high voltage package T 1 The secondary output terminal, capacitor C 3 , spark gap HF and coupled inductor T 2 The primary side of the circuit forms an RLC attenuated oscillation.

[0012] The welding machine main circuit is coupled by coupling inductor T 2 The secondary side of the device connects the boosted high-frequency and high-voltage signal to the main circuit of the welding machine.

[0013] The input energy of the soft-switching zero-voltage oscillation circuit can be obtained by the secondary side rectification and transformation of the main inverter transformer of the arc welding power supply to obtain 12V, which is itself a quasi-resonant self-excited oscillation circuit. The self-excited oscillation is transmitted through the DC high-voltage package T 1 Perform a voltage boost, and then the capacitor C 3 It charges and breaks down the spark gap HF, and a similar RLC decay oscillation occurs. Finally, through the coupled inductor T 2 The secondary boost enters the main circuit of the welding machine.

[0014] Preferably, in the soft-switching zero-voltage oscillation circuit, the inductor L1 is connected to the source of the field-effect transistor Q1 (IRFP260) and the field-effect transistor Q2 (IRFP260), the gate of the field-effect transistor Q1 and the field-effect transistor Q2 is controlled by voltage division by resistors R1 (470Ω), R2 (470Ω), R3 (10kΩ) and R4 (10kΩ), and the drain is connected to the primary side of the high-voltage package T1 via resonant capacitors C1 (100nF) and C2 (100nF).

[0015] Preferably, in the spark gap oscillation circuit, the secondary output end of the high-voltage package T1 charges the capacitor C3 (470pF), and after the spark gap HF is broken down, an attenuated oscillation is formed through the primary side of the coupling inductor T2.

[0016] Preferably, in the coupling of the welding machine main circuit, the secondary side of the coupling inductor T2 is connected in series to the welding machine main circuit to directly act on the gap between the tungsten electrode and the workpiece.

[0017] Preferably, the input power of the soft switch zero voltage oscillation circuit is provided by the DC / DC module after rectification of the secondary side of the main inverter transformer of the welding machine. In the zero voltage oscillation circuit of the soft switch, its VCC input is 12V output by the arc welding power transformer secondary side rectification after passing through the arc control relay and the DC / DC module, and connected to the zero voltage oscillation circuit of the soft switch.

[0018] Preferably, the high voltage package T 1 Internal integrated rectifier diode D 5 , used to rectify the primary side resonant signal.

[0019] Preferably, the high voltage package T 1 The turns ratio is 12:3000, the coupled inductor T 2 The core is ferrite and the turns ratio is 10:25.

[0020] Preferably, in the soft switching zero voltage oscillation circuit, the diode D 1 and diode D 2 Reverse parallel connection in field effect tube Q 1 and Q 2 Between the drain and source of the field effect tube Q 1 and FET Q 2 Interlock;

[0021] Zener diode D 3 And Zener tube D 4 Connect across Q 1 and Q 2 Between the gate and ground, it is used to clamp the gate voltage to a preset safety value to prevent overvoltage damage.

[0022] Preferably, the diode D 1 and diode D 2 It is a fast recovery diode FR107, with a reverse recovery time of ≤100ns; the voltage regulator D 3 And Zener tube D 4 It is a 1N4172 type Zener diode with a clamping voltage of 12V±5%, which matches the gate drive voltage.

[0023] Therefore, the present invention adopts a low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding with the above structure, which has the following beneficial effects:

[0024] The present invention provides a method for measuring conducted interference related to non-contact arc striking, namely, measurement under two working conditions: welding no-load (arc striking circuit works but no arc forms) and arc striking moment; the present invention applies a soft-switching zero-voltage circuit to non-contact arc striking, and proposes a novel non-contact arc striking device, which has self-excited oscillation without the need for external drive, and controls energy release through a spark gap, thereby improving system stability, supporting a variety of energy input methods (main transformer, industrial frequency rectification, battery), and being suitable for different industrial scenarios; by comparing domestic and foreign products under two working conditions, the proposed new non-contact arc striking circuit effectively reduces conducted interference at no-load and at the moment of arc striking.

[0025] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A zero voltage oscillation arc starting device circuit for soft switching;

[0027] Figure 2 This is a schematic diagram of conducted interference testing;

[0028] Figure 3 Q 1 and Q 2 Gate voltage;

[0029] Figure 4 It is the current and voltage signal of a single field effect tube;

[0030] Figure 5 T 1 Primary voltage signal;

[0031] Figure 6 It is the arc starting signal between the tungsten electrode and the workpiece;

[0032] Figure 7 It is the quasi-peak value comparison of the live wire when welding without load;

[0033] Figure 8 It is the quasi-peak comparison of the live line at the moment of arcing;

[0034] Fig. 9 These are the quasi-peak values ​​of the fire line of the Fronius iWave230 under two working conditions. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0036] Unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The words "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0037] Example

[0038] like Figure 1 As shown, the present invention provides a high-frequency and high-voltage arc-starting device with low interference for tungsten inert gas arc welding, comprising the following circuits:

[0039] Soft switching zero voltage oscillation circuit, composed of inductor L 1 , Field Effect Transistor Q 1 , Field Effect Transistor Q 2 , resonant capacitor C 1 , resonant capacitor C 2 And high voltage package T 1 Composition: input 12V DC power supply, generate high-frequency AC signal through push-pull self-excited quasi-resonance;

[0040] Spark gap oscillation circuit: composed of high voltage package T 1 The secondary output terminal, capacitor C 3 , spark gap HF and coupled inductor T 2 The primary side of the circuit forms an RLC attenuated oscillation.

[0041] The welding machine main circuit is coupled by coupling inductor T 2 The secondary side of the device connects the boosted high-frequency and high-voltage signal to the main circuit of the welding machine.

[0042] The input energy of the soft-switching zero-voltage oscillation circuit can be obtained by the secondary side rectification and transformation of the main inverter transformer of the arc welding power supply to obtain 12V, which is itself a quasi-resonant self-excited oscillation circuit. The self-excited oscillation is transmitted through the DC high-voltage package T 1 Perform a voltage boost, and then the capacitor C 3 It charges and breaks down the spark gap HF, and a similar RLC decay oscillation occurs. Finally, through the coupled inductor T 2 The secondary boost enters the main circuit of the welding machine.

[0043] In the soft-switching zero-voltage oscillation circuit, the inductor L1 is connected to the source of the field-effect transistor Q1 (IRFP260) and the field-effect transistor Q2 (IRFP260), the gate of the field-effect transistor Q1 and the field-effect transistor Q2 is controlled by the voltage division of the resistor R1 (470Ω), the resistor R2 (470Ω), the resistor R3 (10kΩ) and the resistor R4 (10kΩ), and the drain is connected to the primary side of the high-voltage package T1 through the resonant capacitor C1 (100nF) and the resonant capacitor C2 (100nF).

[0044] In the soft switching zero voltage oscillation circuit, the diode D 1 and diode D 2 Reverse parallel connection in field effect tube Q 1 and FET Q 2 Between the drain and source of the field effect tube Q 1 and FET Q 2 Interlocking;

[0045] Zener diode D 3 And Zener tube D 4 Connect across Q 1 and Q 2 Between the gate and ground, it is used to clamp the gate voltage to a preset safety value to prevent overvoltage damage.

[0046] Diode D 1 and diode D 2 It is a fast recovery diode FR107, with a reverse recovery time of ≤100ns; the voltage regulator D 3 And Zener tube D 4 It is a 1N4172 type Zener diode with a clamping voltage of 12V±5%, which matches the gate drive voltage.

[0047] In the spark gap oscillation circuit, the secondary output end of the high-voltage package T1 charges the capacitor C3 (470pF), and after breaking down the spark gap HF, an attenuated oscillation is formed through the primary side of the coupling inductor T2.

[0048] In the coupling of the welding machine main circuit, the secondary side of the coupling inductor T2 is connected in series to the welding machine main circuit and directly acts on the gap between the tungsten electrode and the workpiece.

[0049] The input power of the soft switch zero voltage oscillation circuit is provided by the DC / DC module after rectification of the secondary side of the main inverter transformer of the welding machine. In the zero voltage oscillation circuit of the soft switch, its VCC input is rectified by the secondary side of the arc welding power transformer, and then output 12V through the arc control relay and DC / DC module, and connected to the zero voltage oscillation circuit of the soft switch.

[0050] High voltage package T 1 The internal integrated rectifier diode D5 is used to rectify the primary side resonant signal.

[0051] High voltage package T 1 The turns ratio is 12:3000, the coupled inductor T 2 The core is ferrite and the turns ratio is 10:25.

[0052] Workflow:

[0053] S1. Energy input and conversion

[0054] Input source: AC power is obtained from the secondary side of the welding machine's main inverter transformer, converted into DC power by the rectifier circuit, and then outputted as a 12V DC power supply (VCC) through a DC / DC module.

[0055] Function: Provide stable low voltage input for soft switching zero voltage oscillation circuit.

[0056] S2, soft switching zero voltage oscillation

[0057] Push-pull self-excited quasi-resonant:

[0058] Field Effect Transistor Q 1 and Q 2 The gate drive signal (by resistor R 1 -R 4 The two circuits are alternately turned on under the control of a voltage divider network to form a push-pull working mode.

[0059] Inductance L 1 (110μH) and resonant capacitor C 1 / C 2 (100nF) to form a quasi-resonant circuit to ensure Q 1 / Q 2 Switching under zero voltage condition (ZVS) reduces switching losses and EMI.

[0060] High-frequency signal generation: The resonant circuit generates a high-frequency AC signal (the frequency is determined by L 1 , C 1 / C 2 The resonant frequency is determined by the input to the high voltage package T 1 The primary side.

[0061] S3, primary boost and high voltage generation

[0062] Boosting process: High voltage package T 1 (Turns ratio 12:3000) The high-frequency AC signal on the primary side is boosted to a high-voltage AC of several thousand volts.

[0063] Rectification and energy storage: T 1 Internal integrated rectifier diode D 5 , rectifies the secondary high voltage AC into DC, and applies current to capacitor C 3 (470pF) charging.

[0064] S4, Spark Gap Breakdown and RLC Oscillation

[0065] Spark gap conduction: When C 3 When the voltage reaches the breakdown threshold of the spark gap HF (for example, 3kV), HF is instantly turned on to form a discharge channel.

[0066] RLC damped oscillation: C 3 , spark gap HF and coupled inductor T 2 The primary side (10 turns) forms an RLC circuit to generate a high-frequency attenuated oscillation signal.

[0067] S5, secondary voltage boost and arc striking

[0068] Coupling boost: The attenuated oscillation signal passes through the coupling inductor T 2 (Turns ratio 10:25) secondary boost to generate a higher amplitude high frequency high voltage signal.

[0069] Arc ignition output: T 2 The secondary side (25 turns) directly connects the high voltage signal to the main circuit of the welding machine, forming an arc in the air gap between the tungsten electrode and the workpiece, completing non-contact arc initiation.

[0070] The arc ignition device circuit and the conducted interference test platform were built, and the conducted interference test and comparison were carried out between the domestic single-phase argon arc welding WS-250S and the Fronius iWave230. The specific implementation steps are as follows:

[0071] according to Figure 1 The circuit parameters provided are used to build the circuit, where the soft-switching zero-voltage oscillation circuit is composed of resistor R 1 , R 2 , R 3 , R 4 , diode D 1 , D 2 , Zener tube D 3 , D 4 , FET Q 1 , Q 2 , inductance L 1 And DC high voltage package T 1 Composed of 5 It is the rectification inside the high voltage package.

[0072] The no-load voltage on the secondary side of the main inverter transformer is rectified and then converted into 12V DC. Figure 1 Medium VCC. High voltage package T 1 (turns ratio 12:3000), capacitor C 3 and coupled inductor T 2 (turns ratio 10:25) to form a spark gap oscillation circuit, T 2The secondary side is connected in series to the main circuit of the welding machine.

[0073] according to Figure 2 The test platform for conducted interference was built. The linear impedance stabilization network (LISN) used the EM5040B model of Zhiyong Company, the oscilloscope used the SDS824X four-channel oscilloscope of Dingyang, and the high-voltage probe used the RIGOL RP1010H. The interference receiving device used the GW Instek GSP-818 spectrum analyzer, which has an EMI mode and complies with the international electromagnetic compatibility standard CISPR16-1-1. During the test, the high-pass filter at the output end of the LISN was set to 150KHz. The resolution bandwidth RBW and video bandwidth VBW of the spectrum analyzer were set to 9KHz according to the standard. The start frequency was set to 150KHz and the end frequency was set to 30MHz.

[0074] Figure 3 is the gate voltage signal of the field effect tube, proving that Q 1 and Q 2 Alternate push-pull conduction; Figure 4 The current and voltage signals of a single field effect tube confirm the quasi-resonance and close to zero voltage turn-on and turn-off; Figure 5 It is the high voltage package T 1 The primary electrical signal proves that the entire circuit system has produced self-excited oscillation; Figure 6 is the coupled inductor T 2 The voltage on the secondary side is also the arc striking voltage between the tungsten electrode and the workpiece.

[0075] On the single-phase domestic argon arc welding machine WS-250S, the interference of the arc starting method is compared based on the conducted interference test platform, such as Figure 7 and Figure 8 As shown. It is found that when welding without load (arcing), the maximum quasi-peak value of the live wire of the original arc starting circuit is 98.37dBuV, while the zero voltage soft switch arc starting circuit is 85.76dBuV, which is 12.61dB less, which is equivalent to the voltage interference of only 23.4% of the original arc starting. Under the gap of 1mm, when the arc is started normally instantly, the maximum quasi-peak value of the live wire of the original arc starting circuit is 79.78dBuV, while the zero voltage interference is reduced to 70.26dBuV, which is 9.52dB less, which is equivalent to the voltage interference of only 33.4% of the original arc starting.

[0076] Working principle:

[0077] Soft switching zero voltage technology (ZVS):

[0078] Through the inductor L 1 With capacitor C 1 / Capacitance C 2 The resonance of the field effect tube Q 1 / Effect tube Q 2Switching to the on state when the voltage passes through zero avoids the voltage / current mutation of traditional hard switching and significantly reduces electromagnetic interference (EMI).

[0079] Effect tube Q 1 / Effect tube Q 2 The alternating conduction self-excited oscillation mode does not require an external drive signal, simplifies the circuit structure and improves reliability.

[0080] Two-stage boost and energy transmission:

[0081] Through the high voltage package T 1 The 12:3000 turns ratio can boost the low-voltage high-frequency signal to several thousand volts to meet the requirements of breaking through the air gap.

[0082] Coupled inductor T 2 The 10:25 turns ratio further amplifies the voltage, ensuring the stability and strength of the arc ignition signal.

[0083] Spark gap and RLC oscillation:

[0084] The spark gap HF acts as a switching element and only at the capacitor C 3 When the voltage reaches the threshold, it turns on, forming a pulse discharge, reducing the impact of continuous high voltage on the circuit.

[0085] The parameters of the RLC circuit (capacitor C 3 =470pF, coupled inductor T 2 The primary inductor is designed to match the high frequency (about MHz level) required for arc ignition to ensure efficient energy transmission.

[0086] Conducted interference suppression mechanism:

[0087] ZVS technology reduces voltage spikes and current surges during switching, suppressing high-frequency noise at the source.

[0088] The attenuation characteristics of the RLC oscillation signal further weaken the high-frequency harmonics and reduce the conducted interference to the power grid.

[0089] Therefore, the present invention adopts the above-mentioned soft-switching zero-voltage high-frequency high-voltage tungsten-inert gas arc welding arc-starting device. The device generates quasi-resonance through a push-pull self-excitation circuit, reduces the electromagnetic interference of the switch tube, and at the same time, 1 Generate sinusoidal AC input. Circuit oscillation is formed through spark gap HF and other devices, and then coupled inductor T 2 , forming a high-frequency and high-voltage arc-starting electrical signal at the end of the welding gun.

[0090] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding, characterized in that: Includes the following circuits: The soft-switching zero-voltage oscillation circuit is composed of an inductor L1, a field-effect transistor Q1, a field-effect transistor Q2, a resonant capacitor C1, a resonant capacitor C2 and a high-voltage package T1. It inputs a 12V DC power supply and generates a high-frequency AC signal through push-pull self-excited quasi-resonance. Spark gap oscillation circuit: It is composed of the secondary output end of the high-voltage package T1, capacitor C3, spark gap HF and the primary side of the coupled inductor T2 to form an RLC attenuation oscillation; The welding machine main circuit is coupled, and the boosted high-frequency and high-voltage signal is connected to the welding machine main circuit through the secondary side of the coupling inductor T2.

2. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: In the soft switching zero voltage oscillation circuit, the inductor L1 is connected to the source of the field effect transistor Q1 and the field effect transistor Q2, the gate of the field effect transistor Q1 and the field effect transistor Q2 is controlled by the voltage divider of the resistor R1, the resistor R2, the resistor R3 and the resistor R4, and the drain is connected to the primary side of the high-voltage package T1 through the resonant capacitor C1 and the resonant capacitor C2.

3. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: In the spark gap oscillation circuit, the secondary output end of the high-voltage package T1 charges the capacitor C3, and after breaking down the spark gap HF, an attenuated oscillation is formed through the primary side of the coupling inductor T2.

4. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: In the coupling of the welding machine main circuit, the secondary side of the coupling inductor T2 is connected in series to the welding machine main circuit and directly acts on the gap between the tungsten electrode and the workpiece.

5. The low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: The input power of the soft-switching zero-voltage oscillation circuit is provided by the DC / DC module after rectification by the secondary side of the welding machine main inverter transformer.

6. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: The high-voltage package T1 has an internal integrated rectifier diode D5 for rectifying the primary-side resonant signal.

7. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: The turns ratio of the high-voltage coil T1 is 12:3000, and the magnetic core of the coupled inductor T2 is ferrite with a turns ratio of 10:

25.

8. The low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 1, characterized in that: In the soft-switching zero-voltage oscillation circuit, the diode D1 and the diode D2 are connected in reverse parallel between the drain and the source of the field effect transistor Q1 and the field effect transistor Q2, and are used for interlocking the field effect transistor Q1 and the field effect transistor Q2; The voltage regulator D3 and the voltage regulator D4 are respectively connected between the gates of Q1 and Q2 and the ground, and are used to clamp the gate voltage to a preset safety value to prevent overvoltage damage.

9. A low-interference high-frequency and high-voltage arc-starting device for tungsten inert gas arc welding according to claim 8, characterized in that: The diode D1 and the diode D2 are fast recovery diodes FR107, and the reverse recovery time is ≤100ns; the voltage regulator D3 and the voltage regulator D4 are 1N4172 voltage regulator diodes, and the clamping voltage is 12V±5%, which matches the gate drive voltage.

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