Inverter arc welding drive circuit, power circuit system and electric welding machine

Abstract

The invention discloses a drive circuit, a power circuit system and an electric welder for inverter arc welding. The drive circuit comprises a synchronous signal receiving end, a first logic gate module and a second logic gate module. The first logic gate module is connected to the synchronous signal receiving end. The first logic gate module can form a first pulse signal and a second pulse signal according to one of a rising edge and a falling edge of the synchronous signal. The second logic gate module can form a first drive signal according to level information of the synchronous signal and the level information of the first pulse signal. The second logic gate module can form a second drive signal according to the level information of the synchronous signal and the level information of the second pulse signal. In this way, within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flipping moment in the first drive signal and the level flipping moment in the second drive signal. The design utilizes synchronous signal processing to form multiple drive signals, facilitates the control of the inverter arc welding and improves the operation stability.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic circuits, and in particular to a drive circuit, a power loop system and an electric welder for inverter arc welding. Background Art

[0002] Existing electric welding machines need to be equipped with a power circuit system. The power circuit system modulates the output current of the power supply to power welding. The power circuit system generally includes a control module, a symmetrical half-bridge buck module and an inverter module. The control module needs to control the operation of the symmetrical half-bridge buck module and the inverter module respectively. The symmetrical half-bridge buck module steps down the power supply to power the inverter module, and the inverter module modulates the output current to power welding. Therefore, the control module needs to modulate and output multiple drive signals to drive the symmetrical half-bridge buck module and the inverter module respectively. The operating load requirements of the control module are high, control disorder may occur, and the stability is not high. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an inverter arc welding drive circuit, a power circuit system, and an electric welder, which can process synchronous signals to form multiple drive signals, thereby facilitating the control of the inverter arc welding and improving operational stability.

[0004] According to the first aspect of the present invention, an inverter arc welding drive circuit includes: a synchronization signal receiving end for receiving a synchronization signal; a first logic gate module connected to the synchronization signal receiving end, the first logic gate module being capable of forming a first pulse signal and a second pulse signal according to one of a rising edge and a falling edge of the synchronization signal, and the first pulse signal and the second pulse signal are complementary; a second logic gate module connected to the first logic gate module and the synchronization signal receiving end, the second logic gate module being capable of processing the first drive signal according to the level information of the synchronization signal and the level information of the first pulse signal, and the second logic gate module being capable of processing the second drive signal according to the level information of the synchronization signal and the level information of the second pulse signal, so that within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flipping moment in the first drive signal and the level flipping moment in the second drive signal.

[0005] An inverter arc welding drive circuit according to an embodiment of the present invention has at least the following beneficial effects:

[0006] In the inverter arc welding drive circuit, a first logic gate module can be triggered by either the rising edge or the falling edge of a synchronization signal to form complementary first and second pulse signals. The second logic gate module uses the level information of the synchronization signal and the level information of the first pulse signal to form the first drive signal, and uses the level information of the synchronization signal and the level information of the second pulse signal to form the second drive signal. This ensures that, within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flipping moment of the first drive signal and the level flipping moment of the second drive signal. Therefore, when the first drive signal and the second drive signal are used to drive a symmetrical half-bridge buck module, the complementary first and second pulse signals enable the two switching transistors in the symmetrical half-bridge buck module to be turned on and off respectively, thereby modulating the output voltage. However, due to the time difference between the level flipping moment of the first drive signal and the level flipping moment of the second drive signal, the two switching transistors in the half-bridge buck module will not be turned on simultaneously. This design utilizes a single synchronization signal to generate multiple drive signals, facilitating control of the inverter arc welding and improving operational stability.

[0007] According to some embodiments of the present invention, the first logic gate module is a D flip-flop.

[0008] According to some embodiments of the present invention, the second logic gate module includes a first logic gate unit and a second logic gate unit, the first input end of the first logic gate unit is connected to the first output end of the first logic gate module, the second input end of the first logic gate unit is connected to the synchronization signal receiving end, the first input end of the second logic gate unit is connected to the second output end of the first logic gate module, and the second input end of the second logic gate unit is connected to the synchronization signal receiving end.

[0009] According to some embodiments of the present invention, both the first logic gate unit and the second logic gate unit are OR gate circuits.

[0010] According to some embodiments of the present invention, a signal amplification module is further included. The signal amplification module is connected to the second logic gate module, and the signal amplification module is capable of amplifying the first driving signal and the second driving signal.

[0011] According to some embodiments of the present invention, a modulation module is further included. The modulation module is connected to the second logic gate module, and the modulation module is capable of processing the first driving signal and the second driving signal into an integrated signal.

[0012] According to some embodiments of the present invention, the modulation module includes a first switching transistor N1, a second switching transistor N2, a third switching transistor N3, and a fourth switching transistor N4. The input end of the first switching transistor N1 and the input end of the third switching transistor N3 are both connected to a power supply. The output end of the first switching transistor N1 is connected to the input end of the second switching transistor N2 to form one pole of the output end of the modulation module. The output end of the third switching transistor N3 is connected to the input end of the fourth switching transistor N4 to form the other pole of the output end of the modulation module. The output end of the second switching transistor N2 and the output end of the fourth switching transistor N4 are both grounded. The first output end of the second logic gate module is respectively connected to the controlled end of the first switching transistor N1 and the controlled end of the second switching transistor N2. The second output end of the second logic gate module is respectively connected to the controlled end of the third switching transistor N3 and the controlled end of the fourth switching transistor N4.

[0013] According to some embodiments of the present invention, an isolation module is further included, and the second logic gate module is connected to the isolation module.

[0014] According to the second aspect of the present invention, the power circuit system includes a control module, a symmetrical half-bridge buck module, an inverter module and the inverter arc welding drive circuit disclosed in any of the above embodiments, the input end of the symmetrical half-bridge buck module is used to be connected to the power supply, the input end of the inverter module is connected to the output end of the symmetrical half-bridge buck module, the control module is connected to the inverter module to control the operation of the inverter module, the control module is connected to the inverter arc welding drive circuit to provide a synchronization signal, and the inverter arc welding drive circuit is connected to the symmetrical half-bridge buck module to drive the symmetrical half-bridge buck module to operate.

[0015] The power circuit system according to the embodiment of the present invention has at least the following beneficial effects:

[0016] In the power circuit system of the present invention, the control module provides a synchronization signal, and the inverter arc welding drive circuit can generate multiple drive signals for driving the symmetrical half-bridge buck module to operate. The symmetrical half-bridge buck module generates an output voltage and provides it to the inverter module. The control module then controls the inverter module to modulate the output voltage to power the welding process. The control module of this design only needs to provide one synchronization signal, and the inverter arc welding drive circuit can process the synchronization signal to form multiple drive signals, which facilitates the control of the inverter arc welding and improves the operation stability.

[0017] An electric welding machine according to an embodiment of the third aspect of the present invention includes the power circuit system disclosed in the above embodiment.

[0018] The electric welding machine according to the embodiment of the present invention has at least the following beneficial effects:

[0019] In the electric welding machine of the present invention, the control module only needs to provide a synchronization signal, and the inverter arc welding drive circuit can process the synchronization signal to form multiple drive signals, which facilitates the control of the inverter arc welding and improves the operation stability.

[0020] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0022] Figure 1 This is a principle structural block diagram of one embodiment of the power circuit system of the present invention;

[0023] Figure 2 This is a block diagram of the principle structure of one embodiment of the inverter arc welding drive circuit of the present invention;

[0024] Figure 3 A circuit diagram of one embodiment of an inverter arc welding drive circuit according to the present invention;

[0025] Figure 4 This is a waveform diagram of one embodiment of the inverter arc welding drive circuit of the present invention;

[0026] Figure 5 The circuit diagram of the symmetrical half-bridge buck module and inverter module;

[0027] Figure 6 This is a circuit diagram of the control module.

[0028] Reference numerals:

[0029] Control module 100 , symmetrical half-bridge buck module 200 , inverter module 300 , first logic gate module 400 , second logic gate module 500 , first logic gate unit 510 , second logic gate unit 520 , signal amplification module 600 , modulation module 700 , isolation module 800 . DETAILED DESCRIPTION

[0030] The following describes embodiments of the present invention in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended only to explain the present invention and are not to be construed as limiting the present invention.

[0031] In the description of the present invention, it should be understood that descriptions involving orientations, such as the orientations or positional relationships indicated by terms such as "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside", are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0032] In the description of the present invention, "several" means one or more, "many" means more than two, "greater than," "less than," and "exceed" are understood to exclude the number itself, while "above," "below," and "within" are understood to include the number itself. The use of "first" and "second" in the description is solely for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, implicitly specifying the number of the indicated technical features, or implicitly specifying the order of the indicated technical features.

[0033] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood broadly. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0034] like Figure 1 -6, according to the first aspect of the embodiment of the present invention, an inverter arc welding drive circuit includes a synchronization signal receiving end for receiving a synchronization signal, a first logic gate module 400 and a second logic gate module 500, the first logic gate module 400 is connected to the synchronization signal receiving end, the first logic gate module 400 can form a first pulse signal and a second pulse signal according to one of the rising edge and the falling edge of the synchronization signal, and the first pulse signal and the second pulse signal are complementary; the second logic gate module 500 is connected to the first logic gate module 400 and the synchronization signal receiving end, the second logic gate module 500 can form a first drive signal according to the level information of the synchronization signal and the level information of the first pulse signal, and the second logic gate module 500 can form a second drive signal according to the level information of the synchronization signal and the level information of the second pulse signal, so that within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flip moment in the first drive signal and the level flip moment in the second drive signal.

[0035] Among them, the synchronization signal receiving end can be an electrical terminal, wire, pin, etc., which is used to access the signal source that outputs the synchronization signal. It should be noted that the synchronization signal is a signal that provides the same time reference, which can be a switching signal or a continuous pulse, containing timing information.

[0036] In the inverter arc welding drive circuit, the first logic gate module 400 can be triggered by either the rising edge or the falling edge of the synchronization signal to generate complementary first and second pulse signals. The second logic gate module 500 uses the level information of the synchronization signal and the level information of the first pulse signal to generate the first drive signal, and uses the level information of the synchronization signal and the level information of the second pulse signal to generate the second drive signal. This ensures that within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flipping time of the first drive signal and the level flipping time of the second drive signal. Therefore, when the symmetrical half-bridge buck module 200 is driven by the first and second drive signals, the complementary first and second pulse signals can cause the two switches in the symmetrical half-bridge buck module 200 to be turned on and off respectively, thereby modulating the output voltage. However, due to the time difference between the level flipping time of the first drive signal and the level flipping time of the second drive signal, the two switches in the half-bridge buck module will not be turned on simultaneously. This design utilizes a single synchronization signal to generate multiple drive signals, facilitating control of the inverter arc welding and improving operational stability.

[0037] In some embodiments of the present invention, the first logic gate module 400 is a D flip-flop. The D flip-flop has a memory function and is an information storage device with two stable states. It can be flipped from one stable state to another stable state by a signal trigger. Specifically, in the present design, the input end of the D flip-flop is connected to the synchronization signal, and is flipped by one of the trigger levels of the rising edge and the falling edge of the synchronization signal to form a complementary first pulse signal and a second pulse signal, and outputs the first pulse signal through the first output end Q of the D flip-flop, and the second output end of the D flip-flop is Q. Output a second pulse signal.

[0038] The first logic gate module 400 can also be formed by a conventional delay component and an inverter to form a circuit capable of outputting a complementary first pulse signal and a second pulse signal.

[0039] In some embodiments of the present invention, Figure 3 、 4As shown, the second logic gate module 500 includes a first logic gate unit 510 and a second logic gate unit 520. The first input end of the first logic gate unit 510 is connected to the first output end of the first logic gate module 400, and the second input end of the first logic gate unit 510 is connected to the synchronization signal receiving end. The first input end of the second logic gate unit 520 is connected to the second output end of the first logic gate module 400, and the second input end of the second logic gate unit 520 is connected to the synchronization signal receiving end.

[0040] The first logic gate unit 510 and the second logic gate unit 520 are used to process the first pulse signal and the second pulse signal based on the synchronization signal, so that the first pulse signal and the second pulse signal do not interfere with each other.

[0041] Specifically, the first logic gate unit 510 and the second logic gate unit 520 are both OR gate circuits.

[0042] Of course, according to the selection of the switch tube type of the symmetrical half-bridge buck module 200 in the actual welding machine power circuit system, the type of the gate circuit in the first logic gate unit 510 and the second logic gate unit 520 can be adaptively changed. The first logic gate unit 510 and the second logic gate unit 520 can use the same gate circuit or different gate circuits.

[0043] Specifically, the first logic gate unit 510 and the second logic gate unit 520 adopt an OR gate circuit, such as Figure 4 As shown, if at least one of the first pulse signal and the synchronization signal is at a high level, the first drive signal is at a high level; otherwise, the first drive signal is at a low level. Similarly, if at least one of the second pulse signal and the synchronization signal is at a high level, the second drive signal is at a high level; otherwise, the second drive signal is at a low level. As a result, within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flipping moment in the first drive signal and the level flipping moment in the second drive signal.

[0044] In some embodiments of the present invention, Figure 2 、 3 As shown, it also includes a signal amplification module 600, which is connected to the second logic gate module 500. The signal amplification module 600 can amplify the first drive signal and the second drive signal, so that the first drive signal and the second drive signal can drive the symmetrical half-bridge buck module 200.

[0045] Specifically, the signal amplification module 600 may include two 555 timers, so as to respectively amplify the power of the first driving signal and the second driving signal.

[0046] The signal amplification module 600 may also be selected from conventional signal amplification chips, which is not limited here.

[0047] In some embodiments of the present invention, Figure 2 、 3 As shown, it also includes a modulation module 700, which is connected to the second logic gate module 500. The modulation module 700 can process the first drive signal and the second drive signal into an integrated signal. The integrated signal contains the characteristics of the first drive signal and the second drive signal. The integrated signal can be used to drive different switching tubes in the symmetrical half-bridge buck module 200 respectively.

[0048] In some embodiments of the present invention, the modulation module 700 includes a first switching transistor N1, a second switching transistor N2, a third switching transistor N3, and a fourth switching transistor N4. The input end of the first switching transistor N1 and the input end of the third switching transistor N3 are both connected to a power supply. The output end of the first switching transistor N1 is connected to the input end of the second switching transistor N2 to form one terminal of the output end of the modulation module 700. The output end of the third switching transistor N3 is connected to the input end of the fourth switching transistor N4 to form the other terminal of the output end of the modulation module 700. The output end of the second switching transistor N2 and the output end of the fourth switching transistor N4 are both grounded. The first output end of the second logic gate module 500 is respectively connected to the controlled end of the first switching transistor N1 and the controlled end of the second switching transistor N2. The second output end of the second logic gate module 500 is respectively connected to the controlled end of the third switching transistor N3 and the controlled end of the fourth switching transistor N4.

[0049] The first switch tube N1, the second switch tube N2, the third switch tube N3 and the fourth switch tube N4 can be transistors, MOS tubes, IGBTs, etc. The first switch tube N1 and the third switch tube N3 can be N-channel MOS tubes, and the second switch tube N2 and the fourth switch tube N4 can be P-channel MOS tubes, so that Figure 4 The integrated signal waveform is shown.

[0050] In some embodiments of the present invention, Figure 2 、 3 As shown, an isolation module 800 is also included. The second logic gate module 500 is connected to the isolation module 800. The isolation module 800 can isolate signal interference, impact, etc. between the inverter arc welding drive circuit and the symmetrical half-bridge buck module 200.

[0051] Specifically, the isolation module 800 may be a transformer, a photoelectric coupler, or the like.

[0052] According to the power circuit system of the second embodiment of the present invention, Figure 1 、 56, comprising a control module 100, a symmetrical half-bridge buck module 200, an inverter module 300 and the inverter arc welding drive circuit disclosed in any of the above embodiments, the input end of the symmetrical half-bridge buck module 200 is used to be connected to the power supply, the input end of the inverter module 300 is connected to the output end of the symmetrical half-bridge buck module 200, the control module 100 is connected to the inverter module 300 to control the operation of the inverter module 300, the control module 100 is connected to the inverter arc welding drive circuit to provide a synchronization signal, and the inverter arc welding drive circuit is connected to the symmetrical half-bridge buck module 200 to drive the symmetrical half-bridge buck module 200 to operate.

[0053] The control module 100 can be composed of an MCU, a CPU or a conventional control chip and auxiliary circuits. The symmetrical half-bridge buck module 200 can include a switch tube Q1, a switch tube Q2, a capacitor C10, a capacitor C20, a diode D20, a diode D30, a capacitor C30 and a resistor R10. The input end of the switch tube Q1 and one end of the capacitor C10 are both connected to one pole of the power supply. The output end of the switch tube Q1 is respectively connected to the cathode of the diode D20, one end of the capacitor C30 and one end of the resistor R10 to form one pole of the output end of the symmetrical half-bridge buck module 200. The anode of the diode D20 is respectively connected to the cathode of the diode D30, the capacitor C10 and the resistor R10. The other end of the switching tube Q1 and the other end of the switching tube Q2 are connected to the positive electrode of the diode D30 and one end of the capacitor C20, the input end of the switching tube Q2 is respectively connected to the positive electrode of the diode D30, the other end of the capacitor C30, and the other end of the resistor R10 to form the other end of the output end of the symmetrical half-bridge buck module 200. The other end of the capacitor C20 and the output end of the switching tube Q2 are both connected to the other end of the power supply. The controlled electrode of the switching tube Q1 can be connected to the first drive signal, and the controlled electrode of the switching tube Q2 can be connected to the second drive signal. If the input voltage is U1, the operation of the switching tubes Q1 and Q2 can form a voltage of 1 / 2U1 across the capacitor C30, thereby reducing the switching loss of the rear inverter module 300.

[0054] In the power circuit system of the present invention, the control module 100 provides a synchronization signal, and the inverter arc welding drive circuit can generate multiple drive signals for driving the symmetrical half-bridge buck module 200 to operate. The symmetrical half-bridge buck module 200 generates an output voltage and provides it to the inverter module 300. The control module 100 then controls the inverter module 300 to modulate the output voltage to power the welding process. In this design, the control module 100 only needs to provide one synchronization signal, and the inverter arc welding drive circuit can process the synchronization signal to form multiple drive signals, which facilitates the control of the inverter arc welding and improves the operation stability.

[0055] An electric welding machine according to an embodiment of the third aspect of the present invention includes the power circuit system disclosed in the above embodiment.

[0056] In the electric welding machine of the present invention, the control module 100 only needs to provide a synchronization signal, and the inverter arc welding drive circuit can process the synchronization signal to form multiple drive signals, which facilitates the control of the inverter arc welding and improves the operation stability.

[0057] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0058] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A drive circuit for inverter arc welding, characterized in that: include: A synchronization signal receiving end, used for receiving a synchronization signal; a first logic gate module, connected to the synchronization signal receiving end, wherein the first logic gate module is capable of generating a first pulse signal and a second pulse signal according to one of a rising edge and a falling edge of the synchronization signal, and the first pulse signal and the second pulse signal are complementary; The second logic gate module is connected to the first logic gate module and the synchronization signal receiving end. The second logic gate module can process the level information of the synchronization signal and the level information of the first pulse signal to form a first drive signal. The second logic gate module can process the level information of the synchronization signal and the level information of the second pulse signal to form a second drive signal, so that within the same cycle of the first drive signal and the second drive signal, there is a time difference between the level flipping moment in the first drive signal and the level flipping moment in the second drive signal.

2. The inverter arc welding drive circuit according to claim 1, characterized in that: The first logic gate module is a D flip-flop.

3. The inverter arc welding drive circuit according to claim 1, characterized in that: The second logic gate module includes a first logic gate unit and a second logic gate unit, the first input end of the first logic gate unit is connected to the first output end of the first logic gate module, the second input end of the first logic gate unit is connected to the synchronization signal receiving end, the first input end of the second logic gate unit is connected to the second output end of the first logic gate module, and the second input end of the second logic gate unit is connected to the synchronization signal receiving end.

4. The inverter arc welding drive circuit according to claim 3, characterized in that: The first logic gate unit and the second logic gate unit are both OR gate circuits.

5. The inverter arc welding drive circuit according to claim 1, characterized in that: It also includes a signal amplification module, which is connected to the second logic gate module and can amplify the first drive signal and the second drive signal.

6. The inverter arc welding drive circuit according to claim 1, characterized in that: The system further includes a modulation module connected to the second logic gate module. The modulation module can process the first driving signal and the second driving signal into an integrated signal.

7. The inverter arc welding drive circuit according to claim 6, characterized in that: The modulation module includes a first switching transistor N1, a second switching transistor N2, a third switching transistor N3, and a fourth switching transistor N4. The input end of the first switching transistor N1 and the input end of the third switching transistor N3 are both connected to a power supply. The output end of the first switching transistor N1 is connected to the input end of the second switching transistor N2 to form one pole of the output end of the modulation module. The output end of the third switching transistor N3 is connected to the input end of the fourth switching transistor N4 to form the other pole of the output end of the modulation module. The output end of the second switching transistor N2 and the output end of the fourth switching transistor N4 are both grounded. The first output end of the second logic gate module is respectively connected to the controlled end of the first switching transistor N1 and the controlled end of the second switching transistor N2. The second output end of the second logic gate module is respectively connected to the controlled end of the third switching transistor N3 and the controlled end of the fourth switching transistor N4.

8. The inverter arc welding drive circuit according to claim 1, characterized in that: It also includes an isolation module, and the second logic gate module is connected to the isolation module.

9. A power circuit system, characterized in that: It includes a control module, a symmetrical half-bridge buck module, an inverter module and an inverter arc welding drive circuit as described in any one of claims 1 to 8, wherein the input end of the symmetrical half-bridge buck module is used to be connected to a power supply, the input end of the inverter module is connected to the output end of the symmetrical half-bridge buck module, the control module is connected to the inverter module to control the operation of the inverter module, the control module is connected to the inverter arc welding drive circuit to provide a synchronization signal, and the inverter arc welding drive circuit is connected to the symmetrical half-bridge buck module to drive the symmetrical half-bridge buck module to operate.

10. An electric welding machine, characterized in that: Comprising the power circuit system as claimed in claim 9.

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