Welding machine power supply and welding equipment

Abstract

The utility model relates to a welding machine power supply and welding equipment. The welding machine power supply comprises a power supply topology structure which comprises a power factor correction circuit and an inverter circuit; the first control loop is connected with the power factor correction circuit; the second control loop is connected with the inverter circuit; the power factor correction circuit is used for performing power factor correction on the power input signal according to the first feedback control signal and then generating a correction electric signal; the inversion circuit is used for performing inversion processing on the correction electric signal according to the second feedback control signal and then generating a power supply output signal; the first control loop is used for sampling the correction electric signal, performing first pulse width modulation on the correction electric signal and then outputting a first feedback control signal to the power factor correction circuit; and the second control loop is used for sampling the power supply output signal, performing second pulse width modulation on the power supply output signal and then outputting a second feedback control signal to the inverter circuit. The working efficiency and the stability of the welding machine power supply can be improved, and meanwhile the integration degree and the maintainability are improved.

Description

Technical Field

[0001] The present application relates to the field of welding technology, and in particular to a welding power supply and welding equipment. Background Art

[0002] In the field of welding technology, the performance of welding power supplies directly impacts welding quality and efficiency. Silicon carbide (SiC), a new wide-bandgap semiconductor material, boasts excellent properties such as high-temperature resistance, high frequency, high voltage, radiation resistance, and low loss. Therefore, SiC is well-suited for manufacturing high-performance welding power supplies. In recent years, SiC power devices have been widely used in power electronics. Their excellent switching performance and high reliability contribute to improved welding power supply performance.

[0003] However, in actual applications, welding power supplies based on silicon carbide (SiC) power devices generally have a high switching frequency and large iron loss in the magnetic components, which will lead to large overall losses in the welding power supply and increase the design difficulty of various components in the welding power supply (such as magnetic components). In addition, when it comes to high-power equipment, it is often necessary to face the problem of parallel connection of multiple tubes and modules. The unreasonable design of welding power supply products will lead to complex equipment design, difficult assembly, low degree of modularization and other problems. Utility Model Content

[0004] Based on this, the embodiments of the present application provide a welding power supply and welding equipment, which, through modular circuit design and individual modulation of each functional circuit, are conducive to improving the working efficiency and working stability of the welding power supply while improving integration and maintainability.

[0005] To achieve the above objectives, in one aspect, some embodiments of the present application provide a welding power supply. The welding power supply includes a power supply topology, a first control loop, and a second control loop. The power supply topology includes a power factor correction circuit and an inverter circuit connected thereto. The first control loop is connected to the power factor correction circuit, and the second control loop is connected to the inverter circuit. The power factor correction circuit is configured to receive a power supply input signal and a first feedback control signal, and perform power factor correction on the power supply input signal according to the first feedback control signal to generate a correction electrical signal. The inverter circuit is configured to receive the correction electrical signal and the second feedback control signal, and perform inversion processing on the correction electrical signal according to the second feedback control signal to generate a power supply output signal. The first control loop is configured to sample the correction electrical signal, perform a first pulse width modulation on the correction electrical signal, and then output a first feedback control signal to the power factor correction circuit. The second control loop is configured to sample the power supply output signal, perform a second pulse width modulation on the power supply output signal, and then output a second feedback control signal to the inverter circuit.

[0006] In some embodiments, the first control loop and the second control loop both include a sampling circuit, a processing circuit, and a pulse width modulation circuit connected in sequence; wherein the sampling circuit of the first control loop is connected to the output end of the power factor correction circuit, and is configured to sample the correction electrical signal and output a first sampling signal to its processing circuit; the processing circuit of the first control loop is configured to perform data processing on the first sampling signal and output a first pulse width modulation control signal to its pulse width modulation circuit; the pulse width modulation circuit of the first control loop is configured to output a first feedback control signal to the input end of the power factor correction circuit according to the first pulse width modulation control signal; the sampling circuit of the second control loop is connected to the output end of the inverter circuit, and is configured to sample the power supply output signal and output a second sampling signal to its processing circuit; the processing circuit of the second control loop is configured to perform data processing on the second sampling signal and output a second pulse width modulation control signal to its pulse width modulation circuit; the pulse width modulation circuit of the second control loop is configured to output a second feedback control signal to the input end of the inverter circuit according to the second pulse width modulation control signal.

[0007] In some embodiments, the welding power supply further includes a sampling control board; wherein the sampling circuit, processing circuit and pulse width modulation circuit of the first control loop and / or the second control loop are integrated on the sampling control board.

[0008] In some embodiments, the welding power supply further includes an isolation drive board; the isolation drive board is located between the sampling control board and the power supply topology structure; the first feedback control signal is transmitted to the power factor correction circuit through the isolation drive board; and the second feedback control signal is transmitted to the inverter circuit through the isolation drive board.

[0009] In some embodiments, the processing circuit comprises a digital chip.

[0010] In some embodiments, the power topology structure is used to connect to a power grid; the welding power supply further includes a suppression circuit connected between the power grid and the power topology structure; the suppression circuit is configured to: receive a voltage signal from the power grid, perform electromagnetic interference suppression processing on the voltage signal, and then output a power input signal to the power topology structure.

[0011] In some embodiments, the welder power supply further includes an auxiliary power supply connected to the power topology.

[0012] In some embodiments, the welding power supply further includes a heat dissipation module connected to the power supply topology structure.

[0013] In some embodiments, the welding power supply further includes a voltage-current conversion module connected to the power supply topology structure; the voltage-current conversion module is used to connect to the welding load; the voltage-current conversion module is configured to: perform voltage-current conversion on the power supply output signal and then output a matching electrical signal to the welding load.

[0014] On the other hand, the present application also provides a welding device according to some embodiments; the welding device includes a welding power supply as described in any one of the aforementioned embodiments of the present application.

[0015] The embodiments of the present application may or at least have the following advantages:

[0016] In an embodiment of the present application, a power supply topology comprising a connected power factor correction circuit and an inverter circuit is provided. A first control loop performs a first pulse width modulation on the power factor correction circuit, while a second control loop performs a second pulse width modulation on the inverter circuit. This means that a two-stage control loop is provided to independently modulate the power factor correction circuit and the inverter circuit in the power supply topology. In this manner, the power factor correction circuit employs interleaved control to improve the switching efficiency of the welding power supply and reduce current ripple in the power supply input signal. By utilizing the zero-voltage switching characteristics of the inverter circuit, the switching loss and electromagnetic interference of the welding power supply are reduced, thereby improving the operating efficiency and stability of the welding power supply. Furthermore, the two-stage control loop enables independent control of each functional circuit in the power supply topology (i.e., the power factor correction circuit and the inverter circuit). This not only facilitates precise control of each signal to obtain an accurate power supply output signal, but also facilitates modular circuit design, independent packaging, and optimization of the control algorithm. This improves the response speed and stability of the welding power supply while also enhancing its integration and maintainability.

[0017] The details of one or more embodiments of the present application are set forth in the following drawings and description. Other features, objects, and advantages of the present application will become apparent from the description, drawings, and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0019] Figure 1 is a structural block diagram of a welding power supply provided in some embodiments;

[0020] Figure 2 is a structural block diagram of another welding power supply provided in some embodiments;

[0021] Figure 3 is a structural block diagram of another welding power supply provided in some embodiments;

[0022] Figure 4is a structural block diagram of another welding power supply provided in some embodiments;

[0023] Figure 5 is a structural block diagram of another welding power supply provided in some embodiments;

[0024] Figure 6 is a structural block diagram of another welding power supply provided in some embodiments;

[0025] Figure 7 is a structural block diagram of another welding power supply provided in some embodiments;

[0026] Figure 8 is a structural block diagram of another welding power supply provided in some embodiments;

[0027] Figure 9 A schematic diagram of a circuit principle of a power factor correction circuit provided in some embodiments;

[0028] Figure 10 A schematic diagram of a circuit principle of a welding power supply provided in some embodiments;

[0029] Figure 11 This is a schematic diagram of the circuit principle of another welding power supply provided in some embodiments.

[0030] Description of reference numerals:

[0031] 1-Power supply topology, 11-Power factor correction circuit, 12-Inverter circuit, 2-First control loop, 21-First sampling circuit, 22-First processing circuit, 23-First pulse width modulation circuit, 3-Second control loop, 31-Second sampling circuit, 32-Second processing circuit, 33-Second pulse width modulation circuit, 4-Sampling control board, 5-Isolation driver board, 6-Grid, 7-Suppression circuit, 8-Auxiliary power supply, 9-Heating module, 10-Current-voltage conversion module, 101-Transformer circuit, 102-Rectifier circuit, L-Welding machine load, D1-First diode, D2-Second diode, D3-Third diode, D4-Fourth diode, D5-Fifth diode, D6-Sixth diode, D7-Seventh diode, D8-Eighth diode, D9-Ninth diode, D10-tenth diode, D11-eleventh diode, D12-twelfth diode, D13-thirteenth diode, D14-fourteenth diode, D15-fifteenth diode, D16-sixteenth diode, D17-seventeenth diode, D18-eighteenth diode, D19-nineteenth diode, D20-twentieth diode, L1-first inductor, L2-second inductor, L3-third inductor, Lr-rectifier inductor, CS0-first current sensor, CS1-second current sensor, CT-current transformer, T-high frequency transformer, Q1-first transistor, Q2-second transistor, S1-third transistor, S2-fourth transistor, S3-fifth transistor, S4-sixth transistor, C1-first capacitor, C2-second capacitor, C3-third capacitor. DETAILED DESCRIPTION

[0032] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The drawings illustrate preferred embodiments of the present application. However, the present application may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application pertains. The terms used herein in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application.

[0034] It should be understood that when an element or layer is referred to as being "on," "adjacent to," or "connected to" another element or layer, it may be directly on, adjacent to, connected to, or coupled to the other element or layer, or there may be intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, doping types, and / or portions, these elements, components, regions, layers, doping types, and / or portions should not be limited by these terms. These terms are merely used to distinguish one element, component, region, layer, doping type, or portion from another element, component, region, layer, doping type, or portion. Thus, a first element, component, region, layer, doping type, or portion discussed below may be represented as a second element, component, region, layer, or portion without departing from the teachings of the present application.

[0035] As used herein, the singular forms "a," "an," and "the" may also include the plural forms, unless the context clearly indicates otherwise. It should also be understood that when the terms "comprising" and / or "including" are used in this specification, they may specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. At the same time, when used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0036] While embodiments of the present invention are described herein with reference to cross-sectional illustrations that are schematic illustrations of idealized embodiments (and intermediate structures) of the present invention, variations from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are to be expected. Embodiments of the present invention should not be limited to the specific shapes of regions illustrated herein, but rather include deviations in shapes due to, for example, manufacturing techniques. Therefore, the regions shown in the figures are schematic in nature, and their shapes do not represent the actual shapes of regions of a device and do not limit the scope of the present invention.

[0037] The embodiments of the present application provide a welding power supply and welding equipment, which, through modular circuit design and individual modulation of each functional circuit, are conducive to improving the working efficiency and working stability of the welding power supply while improving integration and maintainability.

[0038] In some embodiments, see Figure 1The welding power supply includes a power supply topology 1, a first control loop 2, and a second control loop 3. The power supply topology 1 includes a connected power factor correction circuit 11 and an inverter circuit 12. The first control loop 2 is connected to the power factor correction circuit 11, and the second control loop 3 is connected to the inverter circuit 12. The power factor correction circuit 11 is configured to receive a power supply input signal and a first feedback control signal, and perform power factor correction on the power supply input signal according to the first feedback control signal to generate a correction electrical signal. The inverter circuit 12 is configured to receive the correction electrical signal and a second feedback control signal, and perform inversion processing on the correction electrical signal according to the second feedback control signal to generate a power supply output signal. The first control loop 2 is configured to sample the correction electrical signal, perform a first pulse width modulation on the correction electrical signal, and then output a first feedback control signal to the power factor correction circuit 11. The second control loop 3 is configured to sample the power supply output signal, perform a second pulse width modulation on the power supply output signal, and then output a second feedback control signal to the inverter circuit 12.

[0039] In some examples, the power factor correction circuit 11 includes a three-level boost (TL-Boost) converter.

[0040] It should be noted that the TL-Boost converter implements the power factor correction (PFC) function. By controlling the waveform of the power input current and synchronizing it with the waveform of the power input voltage, the power factor is improved and the harmonic content is reduced. It can effectively solve problems such as signal waveform distortion, electromagnetic interference (EMI) and electromagnetic compatibility (EMC) caused by capacitive loads.

[0041] In some examples, the inverter circuit 12 may be a phase-shifted full-bridge topology, for example.

[0042] It should be noted that the phase-shifted full-bridge topology has a zero voltage switching (ZVS) characteristic, which effectively reduces switching losses and electromagnetic interference in the power supply topology 1.

[0043] In some examples, the phase-shifted full-bridge topology includes silicon carbide (SiC) power devices; for example, they may be silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs), silicon carbide (SiC) insulated gate bipolar transistors (IGBTs), etc.

[0044] It should be noted that silicon carbide (SiC) power devices have the properties of high temperature resistance, high frequency, high voltage, radiation resistance, low loss, and fast switching speed. The embodiment of the present application uses silicon carbide (SiC) power devices as the core switching elements of the welding power supply, which can effectively solve the performance limitation problem of the welding power supply in extreme working environments such as high temperature and high voltage, and improve the working efficiency and operation stability of the welding power supply.

[0045] In an embodiment of the present application, a power supply topology 1 is provided, comprising a connected power factor correction circuit 11 and an inverter circuit 12. A first control loop 2 performs a first pulse width modulation on the power factor correction circuit 11, and a second control loop 3 performs a second pulse width modulation on the inverter circuit 12. In other words, a two-stage control loop is provided to separately modulate the power factor correction circuit 11 and the inverter circuit 12 in the power supply topology 1. In this manner, the switching efficiency of the welding power supply is improved and the current ripple of the power supply input signal is reduced by employing interleaved control of the power factor correction circuit 11. Furthermore, the zero-voltage switching characteristics of the inverter circuit 12 are utilized to reduce the switching loss and electromagnetic interference of the welding power supply, thereby improving the operating efficiency and stability of the welding power supply. In addition, by setting up a two-stage control loop to achieve independent control of each functional circuit in the power supply topology structure 1 (i.e., the power factor correction circuit 11 and the inverter circuit 12), it is not only beneficial to achieve precise control of each signal to obtain a precise power output signal, but also beneficial to achieve modular design of the circuit, independent packaging and optimization of the control algorithm, thereby improving the response speed and stability of the welding power supply while also improving the integration and maintainability of the welding power supply.

[0046] It is understood that the first control loop 2 and / or the second control loop 3 mentioned in the above embodiments may be implemented in a variety of ways, and the structures of the components of the first control loop 2 and / or the second control loop 3 may also be implemented in a variety of ways. The present disclosure does not impose any specific restrictions on this, and is limited to the ability to achieve the corresponding functions.

[0047] In some embodiments, see Figure 2The first control loop 2 and the second control loop 3 both include a sampling circuit, a processing circuit, and a pulse width modulation circuit connected in sequence; wherein the first sampling circuit 21 of the first control loop 2 is connected to the output end of the power factor correction circuit 11, and is configured to sample and correct the electrical signal and then output a first sampling signal to the first processing circuit 22; the first processing circuit 22 of the first control loop 2 is configured to perform data processing on the first sampling signal and then output a first pulse width modulation control signal to the first pulse width modulation circuit 23; the first pulse width modulation circuit 23 of the first control loop 2 is configured to process the first sampling signal according to the first pulse width modulation control signal The first feedback control signal is output to the input end of the power factor correction circuit 11; the second sampling circuit 31 of the second control loop 3 is connected to the output end of the inverter circuit 12, and is configured to sample the power supply output signal and then output a second sampling signal to the second processing circuit 32; the second processing circuit 32 of the second control loop 3 is configured to perform data processing on the second sampling signal and then output a second pulse width modulation control signal to the second pulse width modulation circuit 33; the second pulse width modulation circuit 33 of the second control loop 3 is configured to output a second feedback control signal to the input end of the inverter circuit 12 according to the second pulse width modulation control signal.

[0048] By way of example, the first sampling signal and / or the second sampling signal may be discrete digital signals.

[0049] Illustratively, the processing circuit includes a digital chip.

[0050] It should be noted that in the embodiment of the present application, digital pulse width modulation (PWM) is achieved by sampling the correction electrical signal and the power supply output signal to perform signal processing and signal modulation based on discrete digital signals, which is conducive to achieving precise control of the power supply input signal and the power supply output signal.

[0051] Illustratively, the first feedback control signal and / or the second feedback control signal includes a duty cycle control signal.

[0052] In some embodiments, see Figure 3 The welding power supply further includes a sampling control board 4 ; wherein the sampling circuit, processing circuit and pulse width modulation circuit of the first control loop 2 and / or the second control loop 3 are integrated on the sampling control board 4 .

[0053] In some examples, the first sampling circuit 21 , the first processing circuit 22 , the first pulse width modulation circuit 23 , the second sampling circuit 31 , the second processing circuit 32 , and the second pulse width modulation circuit 33 are integrated on the same sampling control board 4 .

[0054] In some embodiments, see Figure 4The welding machine power supply also includes an isolation drive board 5; the isolation drive board 5 is located between the sampling control board 4 and the power supply topology structure 1; the first feedback control signal is transmitted to the power factor correction circuit 11 through the isolation drive board 5; the second feedback control signal is transmitted to the inverter circuit 12 through the isolation drive board 5.

[0055] It should be noted that, according to the above embodiment, please continue to refer to Figure 4 The isolation driver board 5 may be provided with one or more driver circuits, with the driver circuit inputs connected to the first pulse width modulation circuit 23 and the second pulse width modulation circuit 33; and the driver circuit outputs connected to the control terminals of the power factor correction circuit 11 and the inverter circuit 12. The present disclosure does not limit the specific structure of the driver circuits, provided they can achieve the transmission and drive of the first and second feedback control signals.

[0056] In some embodiments, see Figure 5 The power supply topology structure 1 is used to connect to the power grid 6. The welding power supply also includes a suppression circuit 7 connected between the power grid 6 and the power supply topology structure 1. The suppression circuit 7 is configured to: receive a voltage signal from the power grid 6, perform electromagnetic interference suppression processing on the voltage signal, and then output a power input signal to the power supply topology structure 1.

[0057] By way of example, the power grid 6 may be a three-phase power grid or a single-phase-three-phase hybrid power grid.

[0058] In some examples, the suppression circuit 7 includes an electromagnetic interference (EMI) suppression circuit 7 .

[0059] In some embodiments, see Figure 6 The welding power supply also includes an auxiliary power supply 8 connected to the power topology structure 1.

[0060] It should be noted that the auxiliary power supply 8 is independent of the power grid 6 and can be used to power the power topology structure 1 in the event of a failure, power outage or other unexpected situation in the power grid 6, ensuring that the power topology structure 1 can still operate normally when the power grid 6 stops supplying power, effectively improving the operating stability of the welding machine power supply.

[0061] For some examples, see Figure 6 The auxiliary power supply 8 is connected to both the power factor correction circuit 11 and the inverter circuit 12.

[0062] According to the above example, the auxiliary power supply 8 can be used to power the phase power factor correction circuit 11 and / or the inverter circuit 12 .

[0063] For example, the auxiliary power source 8 includes but is not limited to a battery, an uninterruptible power supply (UPS) or a generator.

[0064] In some embodiments, see Figure 7 The welding power supply also includes a heat dissipation module 9 connected to the power topology structure 1.

[0065] For some examples, see Figure 7 , the heat dissipation module 9 is connected to the auxiliary power supply 8.

[0066] It should be noted that the auxiliary power supply 8 can also be used to supply power to the heat dissipation module 9, which can achieve the independence between the power consumption of the heat dissipation module 9 and the power consumption of the power topology structure 1, which is conducive to the modular design and independent packaging of the circuit, and improves the operating stability of the welding machine power supply.

[0067] In some examples, the heat dissipation module 9 includes but is not limited to a fan, etc.

[0068] In the embodiment of the present application, a heat dissipation module 9 is provided to dissipate heat from the power topology structure 1, thereby reducing the heat loss of the welding power supply, effectively solving the problem of performance limitation of the welding power supply in a high temperature environment, and being beneficial to improving the performance of the welding power supply.

[0069] In some embodiments, see Figure 8 The welding power supply also includes a voltage-current conversion module connected to the power topology structure 1; the voltage-current conversion module is used to connect the welding load L; the voltage-current conversion module is configured to: perform voltage-current conversion on the power supply output signal and then output a matching electrical signal to the welding load L.

[0070] In some embodiments, please refer to Figure 8 The voltage-current conversion module includes a transformer circuit 101 and a rectifier circuit 102. The transformer circuit 101 is connected to the inverter circuit 12. The rectifier circuit 102 is connected to the transformer circuit 101. The welding machine load L is connected to the rectifier circuit 102. The transformer circuit 101 is configured to receive a power supply output signal, transform the power supply output signal, and generate a transformed signal. The rectifier circuit 102 is configured to receive the transformed signal, rectify the transformed signal, and generate a matching electrical signal, which is then output to the welding machine load L.

[0071] Illustratively, the voltage conversion circuit 101 includes a high-frequency transformer.

[0072] In order to more clearly illustrate the welding power supply provided in the embodiments of the present application, the following embodiments are described in detail using the example of a single-phase-three-phase hybrid power grid 6, a power factor correction circuit 11 being a three-level boost (TL-Boost) converter, and an inverter circuit 12 including a phase-shifted full-bridge topology structure.

[0073] In some embodiments, see Figure 9 The power factor correction circuit 11 is connected to the power grid 6; the power grid 6 is a three-phase power grid, including a first phase output Ua, a second phase output Ub and a third phase output Uc; the power factor correction circuit 11 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a sixth diode D6, a seventh diode D7, an eighth diode D8, a first inductor L1, a second inductor L2, a first current sensor CS0, a first transistor Q1, a second transistor Q2, a first capacitor C1 and a second capacitor C2.

[0074] For example, the first transistor Q1 and / or the second transistor Q2 include but are not limited to silicon carbide (SiC) metal oxide semiconductor field effect transistors (MOSFETs).

[0075] Please continue to see Figure 9 , the cathode of the second diode D2 is connected to the anode of the first diode D1; the cathode of the fourth diode D4 is connected to the anode of the third diode D3; the cathode of the sixth diode D6 is connected to the anode of the fifth diode D5; the cathode of the first diode D1, the cathode of the third diode D3 and the cathode of the fifth diode D5 are all connected; the anode of the second diode D2, the anode of the fourth diode D4 and the anode of the sixth diode D6 are all connected.

[0076] The first phase output Ua of the grid 6 is connected to the anode of the first diode D1 and the cathode of the second diode D2; the second phase output Ub of the grid 6 is connected to the anode of the third diode D3 and the cathode of the fourth diode D4; the third phase output Uc of the grid 6 is connected to the anode of the fifth diode D5 and the cathode of the sixth diode D6.

[0077] The anode of the seventh diode D7 is connected to the cathode of the first diode D1, the cathode of the third diode D3, and the cathode of the fifth diode D5 via the first inductor L1 and the first current sensor CS0. The cathode of the eighth diode D8 is connected to the anode of the second diode D2, the anode of the fourth diode D4, and the anode of the sixth diode D6 via the second inductor L2. The first end of the first transistor Q1 is connected to the anode of the seventh diode D7, and the second end is connected to the cathode of the seventh diode D7 via the first capacitor C1. The cathode of the ninth diode D9 is connected to the first end of the first transistor Q1, and the anode is connected to the second end of the first transistor Q1. The first end of the second transistor Q2 is connected to the anode of the eighth diode D8 via the second capacitor C2 and is connected to the second end of the first transistor Q1. The second end of the second transistor Q2 is connected to the cathode of the eighth diode D8. The cathode of the tenth diode D10 is connected to the first end of the second transistor Q2, and the anode is connected to the second end of the second transistor Q2.

[0078] For example, for a three-phase rectifier bridge, when a three-phase grid is input, the diodes corresponding to the two lines with the largest line voltage difference are turned on; for example, when the line voltage difference (Ua-Ub) between the first-phase input Ua and the second-phase input Ub of the three-phase grid is the largest, and the first-phase input Ua is a forward input and the second-phase input Ub is a reverse input, the first diode D1 and the fourth diode D4 are turned on, and the remaining diodes are turned off.

[0079] For example, for a TL-Boost PFC circuit, the first transistor Q1 and the second transistor Q2 are active control transistors, and their on-duty ratios determine the PFC output voltage. The switching logics of the first transistor Q1 and the seventh diode D7 are mutually exclusive, and the switching logics of the second transistor Q2 and the eighth diode D8 are mutually exclusive. The turn-on time of the second transistor Q2 is half a switching cycle later than that of the first transistor Q1.

[0080] In addition, the power factor correction circuit 11 is also connected to a load circuit; the first end of the load circuit is connected to the cathode of the seventh diode D7, and the second end is connected to the anode of the eighth diode D8. It should be noted that for the sake of clarity of the example, Figure 9 The load circuit is simplified as a resistor R; it can be understood that the load circuit may include an inverter circuit 12 (eg, a phase-shifted full-bridge topology structure) and other circuits connected to the inverter circuit 12.

[0081] It should be noted that in the embodiment of the present application, the first diode D1, the second diode D2, the third diode D3, the fourth diode D4, the fifth diode D5 and the sixth diode D6 constitute a series structure of upper and lower tubes, which effectively reduces the voltage stress of the switching tube devices in the circuit (for example, the first transistor Q1 and / or the second transistor Q2), improves the switching efficiency through staggered control, thereby reducing the inductor volume and the power supply input current ripple.

[0082] In some embodiments, see Figure 10 The inverter circuit 12 is connected to the power factor correction circuit 11; the inverter circuit 12 includes at least one phase-shifted full-bridge topology structure connected in parallel. Figure 10 In the figure, the inverter circuit 12 is taken as an example of a two-stage phase-shifted full-bridge topology structure, but it can be understood that the inverter circuit 12 can also be a single-stage phase-shifted full-bridge topology structure or a multi-stage phase-shifted full-bridge topology structure, and the present disclosure does not limit this; and, the phase-shifted full-bridge topology structures at each stage are connected in parallel with each other, and the current-voltage conversion module 10 is set corresponding to the phase-shifted full-bridge topology structure at each stage.

[0083] The single-stage phase-shifted full-bridge topology structure includes: a third transistor S1, a fourth transistor S2, a fifth transistor S3, a sixth transistor S4, a third inductor L3, a third capacitor C3, an eleventh diode D11, a twelfth diode D12, a thirteenth diode D13, a fourteenth diode D14, a fifteenth diode D15 and a sixteenth diode D16.

[0084] Please continue to see Figure 10A first end of the third transistor S1 is connected to the cathode of the seventh diode D7 and the cathode of the eleventh diode D11, and a second end of the third transistor S1 is connected to the anode of the eleventh diode D11 and the cathode of the twelfth diode D12 via the third inductor L3; a first end of the fifth transistor S3 is connected to the anode of the eleventh diode D11 and the cathode of the twelfth diode D12 via the third inductor L3, and a second end of the fifth transistor S3 is connected to the anode of the eighth diode D8 and the anode of the twelfth diode D12; a cathode of the thirteenth diode D13 is connected to the first end of the third transistor S1, and an anode of the thirteenth diode D13 is connected to the second end of the third transistor S1; a cathode of the fourteenth diode D14 is connected to the first end of the fourth transistor S2, An anode of the fourteenth diode D14 is connected to the second end of the fourth transistor S2; a first end of the fourth transistor S2 is connected to the first end of the third transistor S1, and a second end of the fourth transistor S2 is connected to the anode of the eleventh diode D11 via the third capacitor C3; a cathode of the fourteenth diode D14 is connected to the first end of the fourth transistor S2, and an anode of the fourteenth diode D14 is connected to the second end of the fourth transistor S2; a first end of the sixth transistor S4 is connected to the cathode of the twelfth diode D12 via the third capacitor C3, and a second end of the sixth transistor S4 is connected to the anode of the twelfth diode D12; a cathode of the sixteenth diode D16 is connected to the first end of the sixth transistor S4, and an anode of the sixteenth diode D16 is connected to the second end of the sixth transistor S4.

[0085] It should be noted that the on-duty cycle of the third transistor S1, the fourth transistor S2, the fifth transistor S3, and the sixth transistor S4 is all 50%. The third transistor S1 and the fifth transistor S3 form the leading bridge arm, while the fourth transistor S2 and the sixth transistor S4 form the lagging bridge arm. The switching logic of the two switches in the same bridge arm is mutually exclusive. The leading bridge arm is turned on a period earlier than the lagging bridge arm. This period is determined by the phase-shift angle of the phase-shifted full-bridge and directly controls the output current.

[0086] In addition, the eleventh diode D11 and the twelfth diode D12 are clamping diodes, which are turned on when a spike is detected and turned off otherwise.

[0087] For example, the third transistor S1 , the fourth transistor S2 , the fifth transistor S3 and / or the sixth transistor S4 all include but are not limited to silicon carbide (SiC) insulated gate bipolar transistors (IGBTs).

[0088] The voltage transformation circuit 101 includes a current transformer CT and a high-frequency transformer T. The high-frequency transformer T includes a first coil and a second coil. The first coil of the high-frequency transformer T is connected to the inverter circuit 12, and the second coil of the high-frequency transformer T is connected to the rectifier circuit 102. The rectifier circuit 102 includes a seventeenth diode D17, an eighteenth diode D18, a nineteenth diode D19, a twentieth diode D20, a rectifier inductor Lr, and a second current sensor CS1.

[0089] Please continue to see Figure 10 The first end of the first coil of the high-frequency transformer T is connected to the anode of the eleventh diode D11 via the current transformer CT and the third capacitor C3. The second end of the first coil of the high-frequency transformer T is connected to the first end of the sixth transistor S4. The first end of the second coil of the high-frequency transformer T is connected to the anode of the seventeenth diode D17, and the second end of the second coil of the high-frequency transformer T is connected to the cathode of the twentieth diode D20. The cathode of the seventeenth diode D17 is connected to the cathode of the eighteenth diode D18; the anode of the seventeenth diode D17 is connected to the cathode of the nineteenth diode D19; the cathode of the twentieth diode D20 is connected to the anode of the eighteenth diode D18; and the anode of the nineteenth diode D19 is connected to the anode of the twentieth diode D20.

[0090] In addition, the welding machine load L includes a positive electrode V o + and negative electrode V o - Among them, the positive electrode V of the welding machine load L o + The cathode of the eighteenth diode D18 is connected to the second current sensor CS1 and the rectifier inductor Lr; the negative electrode V o - Connected to the anodes of the nineteenth diode D19 and the twentieth diode D20.

[0091] In some embodiments, see Figure 11 The first input terminal of the sampling circuit on the sampling control board 4 is connected to the first current sensor CS0 to sample signals from the power factor correction circuit 11. The second input terminal of the sampling circuit on the sampling control board 4 is connected to the first capacitor C1 and the second capacitor C2 to sample signals from the power factor correction circuit 11 and the inverter circuit 12. The third input terminal of the sampling circuit on the sampling control board 4 is connected to the second current sensor CS1 to sample signals from the current-voltage conversion module 10. (Here, the sampling circuit on the sampling control board 4 includes at least the aforementioned first and second sampling circuits, and may also include other sampling circuits for sampling the output voltage or current of the power grid, etc.)

[0092] In some embodiments, please refer to Figure 11 The output end of the sampling circuit on the sampling control board 4 is connected to the input end of the driving circuit on the isolation driving board 5; the first output end of the driving circuit on the isolation driving board 5 is connected to the control end of the first transistor Q1 and the control end of the second transistor Q2 to control the power factor correction circuit 11, and the second output end of the driving circuit on the isolation driving board 5 is connected to the control end of the thirteenth diode D13, the control end of the fourteenth diode D14, the control end of the fifteenth diode D15, and the control end of the sixteenth diode D16 to control the inverter circuit 12.

[0093] In another aspect, the present application also provides a welding device according to some embodiments; the welding device includes a welding power supply as described in any of the aforementioned embodiments of the present application. This welding device also possesses the technical advantages of the aforementioned welding power supplies. It should be noted that for portions that are identical or corresponding to the aforementioned embodiments, reference can be made to the corresponding descriptions of the aforementioned embodiments and will not be elaborated upon below.

[0094] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above 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.

[0095] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that a person skilled in the art may make various modifications and improvements without departing from the scope of the present application, and these modifications and improvements are all within the scope of protection of the present application.

Claims

1. A welding power supply, characterized in that: include: A power supply topology, including connected power factor correction circuits and inverter circuits; a first control loop connected to the power factor correction circuit; a second control loop connected to the inverter circuit; The power factor correction circuit is configured to: receive a power input signal and a first feedback control signal, and perform power factor correction on the power input signal according to the first feedback control signal to generate a correction electrical signal; The inverter circuit is configured to: receive the correction electrical signal and the second feedback control signal, and generate a power output signal after performing an inversion process on the correction electrical signal according to the second feedback control signal; The first control loop is configured to: sample the correction electrical signal, perform first pulse width modulation on the correction electrical signal, and then output the first feedback control signal to the power factor correction circuit; The second control loop is configured to: sample the power output signal, perform a second pulse width modulation on the power output signal, and then output the second feedback control signal to the inverter circuit.

2. The welding power supply according to claim 1, characterized in that: The first control loop and the second control loop both include: a sampling circuit, a processing circuit and a pulse width modulation circuit connected in sequence; wherein, The sampling circuit of the first control loop is connected to the output end of the power factor correction circuit and is configured to sample the correction electrical signal and output a first sampling signal to its processing circuit; the processing circuit of the first control loop is configured to perform data processing on the first sampling signal and output a first pulse width modulation control signal to its pulse width modulation circuit; the pulse width modulation circuit of the first control loop is configured to output the first feedback control signal to the input end of the power factor correction circuit according to the first pulse width modulation control signal; The sampling circuit of the second control loop is connected to the output end of the inverter circuit and is configured to sample the power supply output signal and output a second sampling signal to its processing circuit; the processing circuit of the second control loop is configured to perform data processing on the second sampling signal and output a second pulse width modulation control signal to its pulse width modulation circuit; the pulse width modulation circuit of the second control loop is configured to output the second feedback control signal to the input end of the inverter circuit according to the second pulse width modulation control signal.

3. The welding power supply according to claim 2, characterized in that: Also included is a sampling control board; The sampling circuit, the processing circuit and the pulse width modulation circuit of the first control loop and / or the second control loop are integrated on the sampling control board.

4. The welding power supply according to claim 3, characterized in that: Also included is an isolated driver board; The isolation driving board is located between the sampling control board and the power supply topology structure; The first feedback control signal is transmitted to the power factor correction circuit through the isolation driving board; The second feedback control signal is transmitted to the inverter circuit through the isolation driving board.

5. The welding power supply according to any one of claims 2 to 4, characterized in that: The processing circuit includes a digital chip.

6. The welding power supply according to claim 1, characterized in that: The power topology structure is used to connect to the power grid; The welding power supply further includes: a suppression circuit connected between the power grid and the power supply topology; The suppression circuit is configured to: receive a voltage signal from the power grid, perform electromagnetic interference suppression processing on the voltage signal, and then output the power input signal to the power topology structure.

7. The welding power supply according to claim 6, characterized in that: Also includes: An auxiliary power supply connected to the power topology structure.

8. The welding power supply according to claim 1, characterized in that: Also includes: A heat dissipation module connected to the power topology structure.

9. The welding power supply according to claim 1, characterized in that: Also includes: A voltage-current conversion module connected to the power topology structure; The voltage-current conversion module is used to connect to a welding machine load, and is configured to: perform voltage-current conversion on the power supply output signal and then output a matching electrical signal to the welding machine load.

10. A welding device, characterized in that: include: The welding power supply according to any one of claims 1 to 9.

Images