An AC / DC composite arc welding power source, a welding system and a control method

Abstract

An embodiment of the present invention discloses an AC-DC composite arc welding power source, a welding system and a control method. The arc welding power source includes an all-in-one machine integrating AC and DC power sources. The all-in-one machine includes a DC unit, an AC unit and a remote control communication port. The DC unit includes a first switching device, a first voltage conversion device, a thyristor rectifier circuit, a first filter circuit, a DC output port, a main control board, a local control panel, a digital communication board and a selection switch. The AC unit includes a second switching device, a rectifier, a primary inverter, a second voltage conversion device, a secondary rectification circuit, a secondary inverter, a second filter circuit, an AC output port, a digital main control board, a drive board, a secondary drive board and a local control digital panel. The effects are as follows: By integrating the AC and DC power sources together, the volume and power consumption are reduced, the characteristics of thyristor type and IGBT inverter type are taken into account, and the complexity of the control system is reduced through the interaction with an external control device via the remote control communication port.

Description

Technical Field

[0001] The present invention relates to the technical field of welding power sources, and particularly relates to an AC / DC composite arc welding power source, a welding system and a control method. Background Art

[0002] At present, arc welding power sources are generally divided into two categories: AC arc welding power sources and DC arc welding power sources, which are distinguished according to the current characteristics of their outputs. The output of an AC arc welding power source is a square wave alternating current, and the output of a DC arc welding power source is a direct current.

[0003] In terms of the power rectification method, the above power sources are further divided into thyristor type and IGBT inverter type models. The thyristor type model has the characteristics of strong welding penetration, high durability, and low maintenance cost; the IGBT inverter type model has the characteristics of small size and power saving.

[0004] At present, the manufacturing of welding power sources is all single-machine AC output or single-machine DC output. In recent years, in the field of heavy steel structure welding, the double-wire double-arc welding method (one AC power source plus one DC power source) has gradually been used to replace the traditional single-wire single-arc (one DC power source) welding method to improve welding efficiency. However, this welding method uses two independent power sources for power supply, and the two power sources are respectively connected to the wire feeding mechanism, resulting in problems such as complex control systems, large volume, large placement area, large power grid interference, and high power consumption. Summary of the Invention

[0005] In order to solve the above problems, the purpose of the present invention is to provide an AC / DC composite arc welding power source, a welding system and a control method that can achieve AC / DC integration to reduce volume and take into account the characteristics of thyristor type and IGBT inverter type.

[0006] First aspect: An AC / DC composite arc welding power source, including an integrated machine integrating AC and DC power sources, the integrated machine includes a DC unit, an AC unit and a remote control communication port for communicating with an external control device;

[0007] The DC unit includes a first switching device, a first voltage conversion device, a thyristor rectification circuit, a first filtering circuit, a DC output port, a main control board, a local control panel, a digital communication board and a selection switch for remote / local control switching;

[0008] The first switching device, the first voltage conversion device, the thyristor rectification circuit, the first filtering circuit and the DC output port are sequentially connected from left to right. The main control board is respectively connected to the first switching device, the thyristor rectification circuit, the selection switch, the local control panel and the digital communication board. The main control board is also connected to the DC output port through a measuring device;

[0009] The AC unit includes a second switching device, a rectifier, a primary inverter, a second voltage conversion device, a secondary rectification circuit, a secondary inverter, a second filtering circuit, an AC output port, a digital main control board, a driving board, a secondary driving board, and a local control digital panel;

[0010] The second switching device, the rectifier, the primary inverter, the second voltage conversion device, the secondary rectification circuit, the secondary inverter, the second filtering circuit, and the AC output port are connected in sequence from left to right. The digital main control board is respectively connected to the driving board, the secondary driving board, and the local control digital panel. The driving board is also connected to the primary inverter, and the secondary driving board is also connected to the secondary inverter. The digital main control board is also connected to the AC output port through a sampling device;

[0011] The digital communication board and the digital main control board are also both connected to the remote control communication port to realize data interaction with an external control device.

[0012] Preferably, the first switching device is a contactor; the second switching device is an air switch.

[0013] Preferably, both the first voltage conversion device and the second voltage conversion device are transformers.

[0014] Preferably, the measuring device is a shunt; the sampling device is a Hall device.

[0015] In a second aspect: A DC-AC composite welding system includes a control device and a DC-AC composite arc welding power source as described in the first aspect;

[0016] The DC-AC composite arc welding power source is connected to the control device through a provided remote control communication port;

[0017] The control device includes a DC wire feeding board, an AC wire feeding board, a traveling board, a parameter setting device, and a main control panel; wherein, when the parameter setting device is configured to set, the generated welding parameters are transmitted to the DC wire feeding board, the AC wire feeding board, and the DC-AC composite arc welding power source;

[0018] The main control panel is respectively connected to the DC wire feeding board and the AC wire feeding board. The DC wire feeding board is also connected to the traveling board and the DC head of an external welding device. The AC wire feeding board is also connected to the AC head of the external welding device; the traveling board is connected to the welding device to control the traveling of the welding device.

[0019] Preferably, communication between the DC-AC composite arc welding power source and the control device is carried out in the RS485 manner.

[0020] Preferably, the main control panel, the DC wire feeding board, the AC wire feeding board, and the DC unit and the AC unit in the AC-DC composite arc welding power source are all set with communication addresses; among them, the main control panel is used as the host, and the rest are used as auxiliary machines.

[0021] Preferably, when the host communicates with each auxiliary machine, after the host receives the signal fed back by the corresponding auxiliary machine, it is sent to the next auxiliary machine, and so on, to establish the communication between the host and each auxiliary machine and realize the transmission of control signals.

[0022] Third aspect: A control method for an AC-DC composite welding system, which is applied to the AC-DC composite welding system described in the second aspect, and the method includes:

[0023] Establish a connection between the AC-DC composite welding system and an external welding device;

[0024] Set welding parameters and transmit the generated welding parameters to the control device and the AC-DC composite arc welding power source;

[0025] Generate a wire feeding command; wherein, the wire feeding command is obtained by triggering through an input device;

[0026] In response to the welding parameters and the wire feeding command, drive the welding device to feed the DC and AC welding wires to the workpiece and perform welding according to a preset welding strategy.

[0027] Preferably, the welding strategy is:

[0028] At the start of welding, first start the DC. When the DC starts and welding begins, then start the AC and add the AC part to the welding;

[0029] After welding is completed, first stop the DC welding, and then stop the AC welding.

[0030] Adopting the above technical solution, an AC-DC composite arc welding power source, a welding system and a control method proposed by the present invention integrate the AC and DC power supplies together, replace the traditional single-wire and single-arc welding method, reduce the volume and power consumption, take into account the characteristics of thyristor type and IGBT inverter type, and realize unified data interaction with an external control device through the provided remote control communication port to reduce the complexity of the control system. Brief Description of the Drawings

[0031] Figure 1 It is an overall schematic diagram of an AC-DC composite arc welding power source provided by an embodiment of the present invention;

[0032] Figure 2 For Figure 1 It is a schematic structural diagram of a main control board provided by the DC unit in

[0033] Figure 3 Schematic diagram of the structure of an AC-DC composite welding system provided by an embodiment of the present invention;

[0034] Figure 4 is Figure 3 Schematic diagram of the internal structure of the control device described in;

[0035] Figure 5 Flowchart of a control method for an AC-DC composite welding system provided by an embodiment of the present invention. Detailed implementation manners

[0036] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0037] As Figure 1 , Figure 2 shown, an embodiment of the present invention provides an AC-DC composite arc welding power source, including an all-in-one machine integrating AC and DC power sources. The all-in-one machine includes a DC unit, an AC unit, and a remote control communication port for communicating with an external control device;

[0038] The DC unit includes a first switching device, a first voltage conversion device, a thyristor rectifier circuit (i.e., Figure 1 the controlled rectification in), a first filter circuit (i.e., Figure 1 the first filter in), a DC output port (i.e., Figure 1 the DC output in), a main control board, a local control panel, a digital communication board, and a selection switch for remote / local control switching;

[0039] The first switching device, the first voltage conversion device, the thyristor rectifier circuit, the first filter circuit, and the DC output port are sequentially connected from left to right. The main control board is respectively connected to the first switching device, the thyristor rectifier circuit, the selection switch, the local control panel, and the digital communication board. The main control board is also connected to the DC output port through a measuring device;

[0040] The AC unit includes a second switching device, a rectifier, a primary inverter, a second voltage conversion device, a secondary rectifier circuit, a secondary inverter, a second filter circuit, an AC output port, a digital main control board, a driver board, a secondary driver board, and a local control digital panel;

[0041] The second switching device, rectifier, primary inverter, second voltage conversion device, secondary rectification circuit, secondary inverter, second filtering circuit and AC output port are connected in sequence from left to right. The digital main control board is respectively connected to the drive board, secondary drive board and local control digital panel. The drive board is also connected to the primary inverter. The secondary drive board is also connected to the secondary inverter. The digital main control board is also connected to the AC output port through a sampling device;

[0042] Both the digital communication board and the digital main control board are also connected to the remote control communication port to realize data interaction with an external control device.

[0043] Specifically, during implementation, the all-in-one machine further includes a box body, a power input interface, etc. well-known to those skilled in the art. Some of the related devices described above are located inside the box body, and some are arranged on the box body. Various output ports, button switches and indicator lights are provided on the box body. For example, a power switch, a stop switch, a start switch, a power indicator, a welding indicator, a thermal protection indicator, etc. Various output ports include the DC output port, AC output port, remote control communication port and a workpiece interface for connecting a workpiece;

[0044] As can be seen from the drawings, the first switching device uses a contactor; the second switching device uses an air switch;

[0045] Both the first voltage conversion device and the second voltage conversion device use transformers;

[0046] The measuring device uses a shunt; the sampling device uses a Hall device;

[0047] Among them, the first filtering circuit uses an inductor; the thyristor rectification circuit includes a diode and three thyristors (SCRs); the selection switch can use a two-stage or three-stage switch, which is not limited here; the local control panel is composed of a pointer meter, a potentiometer and a toggle switch, and the functions of local control and remote control can be switched through the panel toggle switch; this DC power supply part is placed with a digital communication board (ZZ-VIIZJDP-YKZ-190605) on the basis of previous mature technologies to make it have a 485 communication function; it can be connected to an external control box through the communication board to control the DC main control board (MZN-V2). MZN-V2 includes multiple interfaces, represented by CN1-CN7. Among them, CN2 is used for connection with the thyristor rectification circuit, CN6 can be used for current display, and CN7 can be used for voltage display;

[0048] Correspondingly, in the AC unit, the second filter circuit adopts a π-shaped filter circuit. The model of the primary inverter is IGBT (SGM300AHF12A3TFD); the model of the secondary inverter is IGBT (SKM300GB066D); the model of the digital main control board is NBMZE1000ZB-V3; the model of the drive board is MZ-FC V1; the model of the secondary drive board is QD4; the model of the local control digital panel is NBMZE1000MB-V3.

[0049] In the above solution, by integrating the AC and DC power supplies together, replacing the traditional single-wire single-arc welding method, the volume and power consumption are reduced, taking into account the characteristics of thyristor type and IGBT inverter type, and through the provided remote control communication port, the data interaction with the external control device is unified to reduce the complexity of the control system.

[0050] Furthermore, to achieve linkage with the welding device, referring to Figure 3 、 Figure 4 , the embodiment of the present invention also provides an AC-DC composite welding system, including a control device 1 and an AC-DC composite arc welding power source 2 described in the first aspect; the welding device includes a welding trolley and other welding tools; so that this solution can not only be applied to the welding trolley, but also be assembled on welding carriers such as gantry frames, cantilever frames, cross manipulators, and robotic arms to work.

[0051] The AC-DC composite arc welding power source 2 is connected to the control device through the provided remote control communication port; in this embodiment, the AC-DC composite arc welding power source 2 and the control device 1 communicate through the RS485 method, and the format adopts the MODBUS protocol to achieve the control of the welding machine for welding.

[0052] The control device 1 includes a DC wire feeding board, an AC wire feeding board, a traveling board, a parameter setting device, and a main control panel; among them, when the parameter setting device is configured to set, the generated welding parameters are transmitted to the DC wire feeding board, the AC wire feeding board, and the AC-DC composite arc welding power source; during application, the control device can be integrated in a control box, and the control device is also provided with input devices such as wire feeding switches. Of course, the main control panel can also be used as the input device;

[0053] Specifically, the parameter setting device includes voltage and current knobs for controlling the DC part, and voltage and current knobs for the AC part;

[0054] The main control panel is respectively connected to the DC wire feeding board and the AC wire feeding board. The DC wire feeding board is further connected to the traveling board and the DC torch of the external welding device 3. The AC wire feeding board is further connected to the AC torch of the external welding device 3. The traveling board is connected to the welding device to control the traveling of the welding device 3.

[0055] Specifically, the main control panel, the DC wire feeding board, the AC wire feeding board, and the DC unit and the AC unit in the AC / DC composite arc welding power source are all set with communication addresses. Among them, the main control panel is used as the host, and the rest are used as auxiliary machines. For example, the address of the main control panel is set to 2#, the address of the DC wire feeding board is set to 1#, the address of the DC unit is set to 3#, the address of the AC unit is set to 4#, and the address of the AC wire feeding board is set to 5#.

[0056] Further, during welding, communication is established first. The main control and each auxiliary machine need to transmit control signals. The control signals can be triggered and generated by the main control panel or the parameter setting device, which is not limited here.

[0057] Specifically, when the host communicates with each auxiliary machine, after the host receives the signal fed back by the corresponding auxiliary machine, it is then sent to the next auxiliary machine, and so on in a cycle to establish the communication between the host and each auxiliary machine and realize the transmission of control signals.

[0058] Continuing with the example given above, first send a signal from the main control panel 2# to the address 1#, and after receiving the feedback from 1#, then send it to the address 3#. After the main control panel 2# receives the feedback from 3#, then send it to the address 4#. After the main control panel 2# receives the feedback from 4#, it is sent to the address 5# again, and so on in a cycle to establish communication.

[0059] Then, through the main control panel 2#, the wire feeding switch sends commands to the DC wire feeding board 1# and the AC wire feeding board 5# respectively to feed the DC and AC welding wires to the workpiece.

[0060] Finally, first start the DC and send start commands to 1# and 3#. When the DC starts, welding begins. Then, through the main control panel 2#, send start commands to 4# and 5# to add the AC part to the welding. After welding is completed, the main control panel 2# first sends stop commands to 1# and 3#, and then sends stop commands to the AC 4# and 5#.

[0061] In the above solution, by using the AC / DC composite arc welding power source, two wire feeding mechanisms can be directly connected to respectively output alternating current and direct current, and combined with the control device, so that the two constitute a welding control system, achieving the double-arc and double-wire welding method, reducing the complexity of the system, and also avoiding problems such as large volume, large placement area, large power grid interference, and high power consumption caused by using two independent power supplies.

[0062] Referring to Figure 5 As shown, an embodiment of the present invention further provides a control method for an AC / DC composite welding system, which is applied to an AC / DC composite welding system described above. The composition of the welding system is as described above and will not be repeated here. The method includes:

[0063] S101, establish a connection between the AC / DC composite welding system and an external welding device.

[0064] Specifically, the AC / DC composite arc welding power source is connected to the control device through a remote control communication port provided; the main control panel is respectively connected to the DC wire feeding board and the AC wire feeding board. The DC wire feeding board is also connected to the traveling board and the DC welding head of the external welding device, and the AC wire feeding board is also connected to the AC welding head of the external welding device; the traveling board is connected to the welding device to control the traveling of the welding device.

[0065] S102, set welding parameters and transmit the generated welding parameters to the control device and the AC / DC composite arc welding power source.

[0066] Specifically, the welding parameters are set through corresponding voltage and current knobs or input devices.

[0067] S103, generate a wire feeding command; wherein, the wire feeding command is obtained by triggering through an input device.

[0068] Specifically, the input device includes an input device such as a wire feeding switch provided in the control device, or an input device using the main control panel.

[0069] S104, in response to the welding parameters and the wire feeding command, drive the welding device to feed the DC and AC welding wires to the workpiece and perform welding according to a preset welding strategy.

[0070] Specifically, the main control panel performs communication transmission of the received welding parameters and corresponding command driving; during control, the main control panel is used as the host, and the rest are used as auxiliary machines; for example, the address of the main control panel is set to 2#, the address of the DC wire feeding board is set to 1#, the address of the DC unit is set to 3#, the address of the AC unit is set to 4#, and the address of the AC wire feeding board is set to 5#; among them, the process of establishing communication refers to the description of the previous system embodiment;

[0071] After the communication is established, then through the main control panel 2#, the wire feeding switch sends commands to the DC wire feeding board 1# and the AC wire feeding board 5# respectively, feeds the DC and AC welding wires to the workpiece, and performs welding according to the preset welding strategy;

[0072] The welding strategy is as follows:

[0073] At the start of welding, first start the DC. When the DC starts and starts welding, then start the AC and add the AC part to the welding;

[0074] After welding is completed, first stop the DC welding, and then stop the AC welding.

[0075] Specifically, following the previous example, that is, first start the DC, send start commands to 1# and 3#, when the DC starts and starts welding, then through the main control panel 2#, send start commands to 4# and 5# to add the AC part to the welding; after welding is completed, the main control panel 2# first sends stop commands to 1# and 3#, and then sends stop commands to the AC 4# and 5#.

[0076] It should be noted that in the several embodiments provided in the present application, it should be understood that the disclosed units and methods can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed mutual coupling or direct coupling or communication connection can be an indirect coupling or communication connection through some interfaces, devices or units, and can also be an electrical, mechanical or other form of connection.

[0077] The above is only the specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention can easily think of various equivalent modifications or substitutions, and these modifications or substitutions should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention should be subject to the protection scope of the claims.

Claims

1. A AC / DC composite arc welding power source, characterized in that, it includes an integrated machine integrating AC and DC power sources, and the integrated machine includes a DC unit, an AC unit, and a remote control communication port for communicating and connecting with an external control device; the DC unit includes a first switching device, a first voltage conversion device, a thyristor rectification circuit, a first filter circuit, a DC output port, a main control board, a local control panel, a digital communication board, and a selection switch for remote / local control switching; the first switching device, the first voltage conversion device, the thyristor rectification circuit, the first filter circuit, and the DC output port are sequentially connected from left to right, the main control board is respectively connected to the first switching device, the thyristor rectification circuit, the selection switch, the local control panel, and the digital communication board, and the main control board is also connected to the DC output port through a measuring device; the AC unit includes a second switching device, a rectifier, a primary inverter, a second voltage conversion device, a secondary rectification circuit, a secondary inverter, a second filter circuit, an AC output port, a digital main control board, a driver board, a secondary driver board, and a local control digital panel; the second switching device, the rectifier, the primary inverter, the second voltage conversion device, the secondary rectification circuit, the secondary inverter, the second filter circuit, and the AC output port are sequentially connected from left to right, the digital main control board is respectively connected to the driver board, the secondary driver board, and the local control digital panel, the driver board is also connected to the primary inverter, the secondary driver board is also connected to the secondary inverter, and the digital main control board is also connected to the AC output port through a sampling device; the digital communication board and the digital main control board are both connected to the remote control communication port to realize data interaction with an external control device; the first filter circuit includes a reactor; the thyristor rectification circuit includes a diode and three thyristors; the selection switch adopts a two-stage or three-stage switch; the local control panel is composed of a pointer meter, a potentiometer, and a toggle switch, and the functions of local control and remote control are switched through the toggle switch; the second filter circuit adopts a π-shaped filter circuit.

2. A AC / DC composite arc welding power source according to claim 1, characterized in that, the first switching device adopts a contactor; the second switching device adopts an air switch.

3. A AC / DC composite arc welding power source according to claim 1, characterized in that, both the first voltage conversion device and the second voltage conversion device adopt transformers.

4. A AC / DC composite arc welding power source according to claim 1, characterized in that, the measuring device adopts a shunt; the sampling device adopts a Hall device.

5. A AC / DC composite welding system, characterized in that, it includes a control device and a AC / DC composite arc welding power source according to any one of claims 1 to 4; the AC / DC composite arc welding power source is connected to the control device through the provided remote control communication port; the control device includes a DC wire feeding board, an AC wire feeding board, a traveling board, a parameter setting device, and a main control panel; wherein, when the parameter setting device is configured to set, the generated welding parameters are transmitted to the DC wire feeding board, the AC wire feeding board, and the AC / DC composite arc welding power source. The main control panel is respectively connected to the DC wire feeding board and the AC wire feeding board. The DC wire feeding board is further connected to the traveling board and the DC head of an external welding device, and the AC wire feeding board is further connected to the AC head of the external welding device; the traveling board is connected to the welding device to control the traveling of the welding device.

6. A DC-AC composite welding system according to claim 5, wherein, communication between the DC-AC composite arc welding power source and the control device is carried out in the RS485 manner.

7. A DC-AC composite welding system according to claim 6, wherein, the main control panel, the DC wire feeding board, the AC wire feeding board, and the DC unit and the AC unit in the DC-AC composite arc welding power source are all provided with communication addresses; among them, the main control panel is used as the host, and the rest are used as slave machines.

8. A DC-AC composite welding system according to claim 7, wherein, when the host communicates with each slave machine, after the host receives the signal fed back by the corresponding slave machine, it is sent to the next slave machine, and so on in a cycle to establish communication between the host and each slave machine and realize the transmission of control signals.

9. A control method for a DC-AC composite welding system, wherein, applied to a DC-AC composite welding system according to claim 5, the method includes: establishing a connection between the DC-AC composite welding system and an external welding device; setting welding parameters and transmitting the generated welding parameters to the control device and the DC-AC composite arc welding power source; generating a wire feeding command; wherein, the wire feeding command is obtained by triggering through an input device; responding to the welding parameters and the wire feeding command to drive the welding device to feed DC and AC welding wires onto the workpiece and perform welding according to a preset welding strategy.

10. A control method for a DC-AC composite welding system according to claim 9, wherein, the welding strategy is: at the start of welding, DC is started first. After DC is started and welding begins, AC is then started and the AC part is also added to the welding; after welding is completed, DC welding is stopped first, and then AC welding is stopped.

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