Power electronic power supply based on integrated power semiconductor module

Abstract

The invention discloses a power supply circuit, a power electronic power supply and an electric welding machine, and relates to the technical field of electric welding machines. The circuit comprises power supply equipment, a main controller and a power unit, a first input end of the power unit is connected with the power supply equipment, a first output end of the power unit is suitable for being connected with an output end of a power supply circuit, an input end of the main controller is connected with an output end of the power unit, and an output end of the main controller is connected with a control end of the power unit; wherein the main controller is used for acquiring the current output voltage of the power unit and outputting a compensation signal according to the current output voltage and a target output voltage, and the power unit is used for processing the output voltage of the power supply equipment according to the compensation signal, so that the output voltage of the power unit reaches the target output voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of welding machines, and particularly to a power supply circuit, a power electronic power supply, and a welding machine. Background Art

[0002] With the rapid development of the manufacturing industry, welding machines, as the core equipment of the welding process, are widely used in many fields such as construction, bridges, automobiles, aerospace, shipbuilding, petrochemical industry, etc. With the continuous progress of technology and the continuous innovation of processes, higher requirements are put forward for the performance of welding machines, especially the performance of the power supply system of welding machines. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to some extent. To this end, the first object of the present invention is to propose a power supply circuit to improve the performance of the power supply system.

[0004] The second object of the present invention is to propose a power electronic power supply.

[0005] The third object of the present invention is to propose a welding machine.

[0006] To achieve the above object, an embodiment of the first aspect of the present invention proposes a power supply circuit. The circuit includes a power supply device, a main controller, and a power unit. The first input end of the power unit is connected to the power supply device, the first output end of the power unit is adapted to be connected to the output end of the power supply circuit, the input end of the main controller is connected to the output end of the power unit, and the output end of the main controller is connected to the control end of the power unit; wherein, the main controller is used to obtain the current output voltage of the power unit and output a compensation signal according to the current output voltage and the target output voltage, and the power unit is used to process the output voltage of the power supply device according to the compensation signal so that the output voltage of the power unit reaches the target output voltage.

[0007] In addition, the power supply circuit according to the embodiment of the present invention may further have the following additional technical features:

[0008] According to an embodiment of the present invention, the power supply device is used to output alternating current. The circuit further includes a power transformer. The primary side of the power transformer is connected to the second output terminal of the power unit, and the secondary side of the power transformer is connected to the second input terminal of the power unit. The power unit includes: an input rectifier circuit, the input end of the input rectifier circuit is adapted to be connected to the first input end of the power unit, and the input rectifier circuit is used to convert the alternating current output by the power supply device into direct current; an inverter sub-circuit, the input end of the inverter sub-circuit is connected to the output end of the input rectifier circuit, the output end of the inverter sub-circuit is adapted to be connected to the second output terminal of the power unit, and the control end of the inverter sub-circuit is adapted to be connected to the control end of the power unit. The inverter sub-circuit is used to perform an inversion process on the direct current output by the input rectifier circuit according to the control signal output by the main controller; a full-wave rectifier sub-circuit, the input end of the full-wave rectifier sub-circuit is adapted to be connected to the second input terminal of the power unit, and the output end of the full-wave rectifier sub-circuit is adapted to be connected to the first output terminal of the power unit. The full-wave rectifier sub-circuit is used to perform full-wave rectification on the output current of the power transformer.

[0009] According to an embodiment of the present invention, the power unit further includes: a power unit controller, the first input end of the power unit controller is adapted to be connected to the control end of the power unit, the second input end of the power unit controller is connected to the output end of the inverter sub-circuit, and the power unit controller is used to obtain the current output current of the inverter sub-circuit and generate a control signal according to the current output current, the target output current and the compensation signal; a drive board, the input end of the drive board is connected to the output end of the drive unit controller, and the output end of the drive board is connected to the control end of the inverter sub-circuit. The drive board is used to control the inverter sub-circuit to perform an inversion process on the output voltage of the power supply device according to the control signal.

[0010] According to an embodiment of the present invention, the input end of the inverter sub-circuit is further adapted to be connected to the third input terminal of the power unit. The circuit further includes: a three-phase power factor correction sub-circuit, the input end of the three-phase power factor correction sub-circuit is connected to the output end of the power supply device, and the output end of the three-phase power factor correction sub-circuit is connected to the third input terminal of the power unit. The three-phase power factor correction sub-circuit is used to perform power factor correction on the output of the power supply device.

[0011] According to an embodiment of the present invention, the main controller includes: a first comparator, an input end of the first comparator is adapted to be connected to an input end of the main controller, and the first comparator is configured to obtain the current output voltage and obtain a voltage difference between the target output voltage and the current output voltage; an analog-to-digital converter, an input end of the analog-to-digital converter is connected to an output end of the first comparator, and the analog-to-digital converter is configured to convert the voltage difference into a digital signal; a voltage-loop digital compensator, an input end of the voltage-loop digital compensator is connected to an output end of the analog-to-digital converter, and the voltage-loop digital compensator is configured to obtain an initial compensation signal according to the digital signal; a digital-to-analog converter, an input end of the digital-to-analog converter is connected to an output end of the voltage-loop digital compensator, an output end of the digital-to-analog converter is adapted to be connected to an output end of the main controller, and the digital-to-analog converter is configured to convert the initial compensation signal into an analog signal to obtain the compensation signal.

[0012] According to an embodiment of the present invention, the power unit controller includes: a second comparator, an input end of the second comparator is adapted to be connected to a second input end of the power unit controller, and the second comparator is configured to obtain the current output current and obtain a current difference between the current output current and the target output current; a current-loop regulator, an input end of the current-loop regulator is connected to an output end of the second comparator, and the current-loop regulator is configured to obtain a first initial signal according to the current difference; a third comparator, a first input end of the third comparator is connected to an output end of the current-loop regulator, a second input end of the third comparator is adapted to be connected to a first input end of the power unit controller, and the third comparator is configured to obtain a difference between the compensation signal and the first initial signal and use the difference as a second initial signal; a PWM modulator, an input end of the PWM modulator is connected to an output end of the third comparator, an output end of the PWM modulator is adapted to be connected to an output end of the power unit controller, and the PWM modulator is configured to obtain a PWM signal according to the second initial signal and use the PWM signal as the control signal.

[0013] According to an embodiment of the present invention, the voltage loop digital compensator includes: a unit delay element configured to output the received data after delaying a preset time; a first multiplier, an input end of the first multiplier being adapted to be connected to an input end of the voltage loop digital compensator, the first multiplier being configured to multiply the digital signal by a first preset parameter to obtain a first multiplication result; a second multiplier, an input end of the second multiplier being adapted to be connected to the input end of the voltage loop digital compensator, the second multiplier being configured to multiply the digital signal by a second preset parameter to obtain a second multiplication result; a first adder, a first input end of the first adder being connected to an output end of the first multiplier, an output end of the first adder being connected to an input end of the unit delay unit, the first adder being configured to add the first multiplication result and the output data of the unit delay element to obtain a first addition result; an anti-saturation element, an input end of the anti-saturation element being connected to the output end of the first adder, an output end of the anti-saturation element being connected to the input end of the unit delay element, the anti-saturation element being configured to obtain a correction signal according to the first addition result, wherein when the first addition result is greater than or equal to a preset upper limit, the correction signal is the preset upper limit, when the first addition result is less than or equal to a preset lower limit, the correction signal is the preset lower limit, and when the first addition result is greater than the preset lower limit and less than the preset upper limit, the correction signal is the first addition result; a second adder, a first input end of the second adder being connected to the output end of the anti-saturation element, a second input end of the second adder being connected to the output end of the second multiplier, an output end of the second adder being adapted to be connected to an output end of the voltage loop digital compensator, the second adder being configured to add the correction signal and the second multiplication result to obtain a second addition result, and using the second addition result as the initial compensation signal.

[0014] According to an embodiment of the present invention, the number of the power units is at least one.

[0015] To achieve the above object, an embodiment of the second aspect of the present invention provides a power electronic power supply including the above-mentioned power supply circuit.

[0016] To achieve the above object, an embodiment of the third aspect of the present invention provides a welding machine including the above-mentioned power electronic power supply.

[0017] According to the power supply circuit, power electronic power supply, and electric welding machine according to the embodiments of the present invention, the circuit includes a power supply device, a main controller, and a power unit. The first input end of the power unit is connected to the power supply device, the first output end of the power unit is adapted to be connected to the output end of the power supply circuit, the input end of the main controller is connected to the output end of the power unit, and the output end of the main controller is connected to the control end of the power unit; wherein, the main controller is used to obtain the current output voltage of the power unit and output a compensation signal according to the current output voltage and the target output voltage, and the power unit is used to process the output voltage of the power supply device according to the compensation signal so that the output voltage of the power unit reaches the target output voltage. Through the setting of the power unit, the structural design of the power supply can be simplified, and the problem of complex assembly structure of the whole machine can be solved.

[0018] Additional aspects and advantages of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a structural block diagram of the power supply circuit according to the embodiment of the present invention;

[0020] Figure 2 is a circuit diagram of an integrated power semiconductor module according to an embodiment of the present invention;

[0021] Figure 3 is a schematic diagram of an integrated power semiconductor module according to an embodiment of the present invention;

[0022] Figure 4 is a cross-sectional view of an integrated power semiconductor module according to an embodiment of the present invention;

[0023] Figure 5 is a circuit diagram of a three-phase power factor correction sub-circuit according to an embodiment of the present invention;

[0024] Figure 6 is a circuit diagram of a power unit according to an embodiment of the present invention;

[0025] Figure 7 is a schematic structural diagram of a power supply circuit according to an embodiment of the present invention;

[0026] Figure 8 is a circuit diagram of a power supply circuit according to an example of the present invention;

[0027] Figure 9 is a circuit diagram of a power supply circuit according to another example of the present invention;

[0028] Figure 10 is a schematic structural diagram of a voltage loop digital compensator according to an embodiment of the present invention;

[0029] Figure 11It is a diagram showing the relationship between the main controller and the power unit controller in an embodiment of the present invention;

[0030] Figure 12 It is a schematic structural diagram of the power supply circuit in another embodiment of the present invention;

[0031] Figure 13 It is a structural block diagram of the power electronic power supply in an embodiment of the present invention;

[0032] Figure 14 It is a structural block diagram of the power electronic power supply in an embodiment of the present invention. Detailed implementation manners

[0033] The following describes the power supply circuit, the power electronic power supply, and the electric welding machine in the embodiments of the present invention with reference to the accompanying drawings. Among them, the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions throughout. The embodiments described with reference to the accompanying drawings are exemplary and should not be construed as limiting the present invention.

[0034] Figure 1 It is a structural block diagram of the power supply circuit in an embodiment of the present invention.

[0035] As Figure 1 shown, the power supply circuit 100 includes a power supply device 101, a main controller 102, and a power unit 103. The first input end of the power unit 103 is connected to the power supply device 101, the first output end of the power unit 103 is adapted to be connected to the output end of the power supply circuit 100, the input end of the main controller 102 is connected to the output end of the power unit 103, and the output end of the main controller 102 is connected to the control end of the power unit 103; wherein, the main controller 102 is used to obtain the current output voltage of the power unit 103, and output a compensation signal according to the current output voltage and the target output voltage, and the power unit 103 is used to process the output voltage of the power supply device 101 according to the compensation signal so that the output voltage of the power unit 103 reaches the target output voltage.

[0036] Specifically, it is set that the power supply circuit 100 includes a power supply device 101, a main controller 102, and a power unit 103. The power unit 103 is a circuit in the power supply circuit 100 for converting the output voltage of the power supply device 101 into the required voltage, and the main controller 102 is a circuit for controlling the power unit 103.

[0037] Among them, the number of the above-mentioned power units 103 is at least one. That is to say, there can be multiple power units 103 in the power supply circuit 100, because each power unit 103 can be used to process the output voltage of the power supply device 101.

[0038] That is to say, since the power supply usually has a relatively complex structure. For example, in the case of an inverter welding machine, its power supply has a process of rectification → inversion → re-rectification. The power loop involves many links, the supporting drive loop is complex, and the manufacturing level requirement is relatively high. Therefore, by setting the above-mentioned power supply circuit 100, the processing of the output voltage of the power supply device 101 is realized by the independently set power unit 103, and the number of power units 103 can be more than one. The power unit 103 can be a pre-manufactured unit and adopts a plug-and-play method. When the power supply circuit 100 needs to work, only the power unit 103 needs to be installed. Moreover, if a certain power unit 103 fails, only need to control this power unit 103 to stop working.

[0039] Moreover, by setting the above-mentioned main controller 102 and power unit 103, self-equalizing current control, fault identification and power sharing mechanism can be realized. The above-mentioned self-equalizing current control means that the main controller 102 automatically identifies the connected power unit 103, performs enabling control on the power unit 103, and receives the current signal uploaded by the power unit 103 for control. After multiple power units 103 are connected, the main controller 102 performs equalizing current control on the multiple power units 103 to make the output currents of the power units 103 consistent. The above-mentioned fault identification and power sharing mechanism means that when an individual power unit 103 fails, the main controller 102 will cut off this power unit 103 and evenly distribute the power to other normal power units 103.

[0040] Thus, the power supply circuit 100 is set to include a power supply device 101, a main controller 102 and a power unit 103. The first input end of the power unit 103 is connected to the power supply device 101, the first output end of the power unit 103 is suitable for connecting to the output end of the power supply circuit 100, the input end of the main controller 102 is connected to the output end of the power unit 103, and the output end of the main controller 102 is connected to the control end of the power unit 103. Among them, the main controller 102 is used to obtain the current output voltage of the power unit 103 and output a compensation signal according to the current output voltage and the target output voltage. The power unit 103 is used to process the output voltage of the power supply device 101 according to the compensation signal so that the output voltage of the power unit 103 reaches the target output voltage. By setting the above-mentioned power unit 103, the structural design of the power supply can be simplified, and the problem of complex overall machine assembly structure can be solved.

[0041] In some embodiments of the present invention, the power supply device 101 is used to output alternating current. The power supply circuit 100 further includes a power transformer. The primary side of the power transformer is connected to the second output terminal of the power unit 103, and the secondary side of the power transformer is connected to the second input terminal of the power unit 103. The power unit 103 includes: an input rectifier circuit. The input terminal of the input rectifier circuit is adapted to be connected to the first input terminal of the power unit. The input rectifier circuit is used to convert the alternating current output by the power supply device 101 into direct current; an inverter sub-circuit. The input terminal of the inverter sub-circuit is connected to the output terminal of the input rectifier circuit. The output terminal of the inverter sub-circuit is adapted to be connected to the second output terminal of the power unit 103. The control terminal of the inverter sub-circuit is adapted to be connected to the control terminal of the power unit 103. The inverter sub-circuit is used to perform an inversion process on the direct current output by the input rectifier circuit according to the control signal output by the main controller 102; a full-wave rectifier circuit. The input terminal of the full-wave rectifier circuit is adapted to be connected to the second input terminal of the power unit 103. The output terminal of the full-wave rectifier circuit is adapted to be connected to the first output terminal of the power unit 103. The full-wave rectifier circuit is used to perform full-wave rectification on the output current of the power transformer.

[0042] Specifically, since the volume of the power transformer is relatively large, usually in cubic meters, if the power transformer is disposed on the power unit 103, it will cause the power unit 103 to be too large in volume and it is difficult to achieve plug and play. Therefore, the power transformer is set independently of the power unit 103. The second input terminal of the power unit 103 is connected to the secondary side of the power transformer, and the second output terminal of the power unit 103 is connected to the primary side of the power transformer. At this time, when voltage increase or decrease is required, the power unit 103 outputs to the primary side of the power transformer, and the power transformer then outputs voltage to the power unit 103.

[0043] At this time, the power unit 103 is provided with an inverter sub-circuit and a full-wave rectifier circuit. The inverter sub-circuit is used to convert the input direct current into alternating current. The alternating current output by the inverter sub-circuit will leave the power unit 103 and enter the power transformer. The power transformer then performs step-up and step-down processing and outputs the processing result to the power unit 103.

[0044] The full-wave rectifier circuit in the power unit 103 will receive the output of the power transformer and perform full-wave rectification on the output current of the power transformer.

[0045] In some embodiments of the present invention, the power unit 103 further includes: a power unit controller, a first input end of the power unit controller is adapted to be connected to a control end of the power unit 103, a second input end of the power unit controller is connected to an output end of the inverter sub-circuit, and the power unit controller is configured to obtain a current output by the inverter sub-circuit and generate a control signal according to the current output, a target output current, and a compensation signal; a driver board, an input end of the driver board is connected to an output end of the driver unit controller, and an output end of the driver board is connected to a control end of the inverter sub-circuit, and the driver board is configured to control the inverter sub-circuit to perform an inversion process on an output voltage of the power supply device 101 according to the control signal.

[0046] Specifically, in order to achieve a better power output, the power unit 103 is provided with a power unit controller. The power unit controller is configured to collect the output current of the inverter sub-circuit to control the inverter sub-circuit according to the output current of the inverter sub-circuit.

[0047] Thus, by providing the main controller 102 and the power unit controller, the main controller 102 samples the output voltage, and the power unit controller samples the current, forming a double closed-loop negative feedback control system with the voltage as the outer loop and the current loop as the inner loop. The voltage outer loop adjusts the performance of the whole machine system by controlling the output voltage; the current inner loop controls the switching period by limiting the current peak value wave by wave to achieve the purpose of stable output.

[0048] It should be noted that the above-mentioned main controller 102 can adopt a programmable digital controller, and the above-mentioned power unit controller can adopt an analog controller.

[0049] In some embodiments of the present invention, the power supply device 101 is configured to output alternating current, a third input end of the power unit is further adapted to be connected to an input end of the inverter sub-circuit, and the power supply circuit 100 further includes: a three-phase power factor correction sub-circuit, an input end of the three-phase power factor correction sub-circuit is connected to an output end of the power supply device 101, and an output end of the three-phase power factor correction sub-circuit is connected to a third input end of the power unit 103, and the three-phase power factor correction sub-circuit is configured to perform power factor correction on the output of the power supply device 101.

[0050] The power unit 103 further includes: an input rectifier sub-circuit, an input end of the input rectifier sub-circuit is adapted to be connected to a first input end of the power unit, and an output end of the input rectifier sub-circuit is connected to an input end of the inverter sub-circuit, and the input rectifier sub-circuit is configured to convert the alternating current output by the power supply device 101 into direct current.

[0051] The following is described with reference to a specific embodiment.

[0052] In this specific embodiment, first, refer to Figure 2, the above-mentioned inverter sub-circuit, full-wave rectifier sub-circuit and input rectifier sub-circuit together constitute an integrated power semiconductor module. In Figure 2 , 201 is the input rectifier sub-circuit, 202 is the inverter sub-circuit, and 203 is the full-wave rectifier sub-circuit.

[0053] The input end of the input rectifier sub-circuit 201 is a three-phase input end, specifically the Figure 2 A terminal, B terminal and C terminal in. The third input end of the above-mentioned power unit 103 includes the Figure 2 DC+ terminal and DC- terminal in, Figure 2 The T1 terminal and T2 terminal in are the second output terminals of the power unit 103, Figure 2 The T3 terminal, T4 terminal and T5 terminal in are the second input terminals of the power unit 103.

[0054] Figure 3 is Figure 2 The schematic diagram of the wafer layout of the integrated power semiconductor module shown. The above-mentioned input rectifier sub-circuit 201 is an input rectifier bridge, including six input rectifier bridge diodes, which are used to convert the input alternating current into direct current. The above-mentioned inverter sub-circuit 202 includes four inverter circuit switching tubes and four external parallel diodes of the inverter circuit switching tubes. The above-mentioned full-wave rectifier sub-circuit 203 includes eight full-wave rectifier circuit diodes, and all are arranged on the substrate.

[0055] Optionally, the above-mentioned power unit controller, drive board and integrated power semiconductor module are integrally designed in structure. The drive board is installed on the integrated power semiconductor module, and the two are connected by welding pins; the power unit controller is installed on the drive board, and the two are connected by welding pins.

[0056] See Figure 4 The schematic diagram of the structure of the power unit 103 shown. The power unit 103 includes a power unit controller, a drive board and an integrated power semiconductor module. The above-mentioned power unit controller is connected to the drive board through a controller-to-drive board connection pin group, and the drive board is connected to the integrated power semiconductor module through a module-to-drive board connection pin group. The integrated power semiconductor module is composed of a housing, silicone gel, suture, power connection terminals, welding layer, insulating substrate, barrel coating layer, wafer, and metal bottom plate.

[0057] The drive board has reserved a plug-in position for the three-phase power factor correction sub-circuit.

[0058] The semiconductors in the above-mentioned inverter sub-circuit 202, full-wave rectifier sub-circuit 203 and input rectifier sub-circuit 201 can use full silicon carbide material wafers or can also select partial silicon carbide material wafers.

[0059] In a specific embodiment of the present invention, the above-mentioned three-phase power factor correction sub-circuit can be referred to Figure 5, including six switching tubes and parallel diodes connected in parallel therewith, where a, b, and c are the three-phase input terminals of the three-phase power factor correction sub-circuit, and n is the single-phase output terminal of the three-phase power factor correction sub-circuit.

[0060] A specific embodiment will be described below.

[0061] In this specific embodiment, the connection relationship among the above-mentioned drive board, power unit controller, and integrated power semiconductor module can be referred to Figure 6 the power unit 103 shown. It can be seen that the power unit 103 includes a drive board, a power unit controller, and an integrated power semiconductor module. The drive board is used to control the inverter circuit switching tubes in the inverter sub-circuit 202 to achieve the control of the inverter sub-circuit 202. V+ and V- are the output terminals of the full-wave rectification sub-circuit 203 to achieve DC output, and the input rectification sub-circuit 201 is used to receive three-phase AC input.

[0062] Refer to Figure 6 It can be known that the power unit 103 is set to include a drive board, a drive unit controller, and an integrated power semiconductor module, and it is set that the integrated power semiconductor module is only composed of switching tubes and diodes. That is, only the drive board, drive unit controller, and integrated power semiconductor module with smaller volume and weight and easy to integrate are integrated into the power unit 103. Devices with larger volume or weight, such as power transformers, power supply devices 101, etc., and devices that are not easy to integrate, such as busbars, are not integrated into the power unit 103, which can achieve the maximum reduction of the volume of the power unit 103 and meet the plug-and-play requirements of the power unit 103.

[0063] During the overall assembly, an input filter, a DC bus capacitor, a power transformer, and an output filter are connected outside the power unit 103. When there are multiple power units 103, the three-phase inputs of each power unit 103 are connected, the DC buses are connected, and the outputs are connected.

[0064] Refer to Figure 7 , it can be seen that the above-mentioned power supply device 101 includes three AC power supplies and an EMC (Electromagnetic Compatibility electromagnetic compatibility filter).

[0065] Figure 8 This is a specific embodiment where the number of the above-mentioned power units 103 is one. Figure 9 This is a specific embodiment where the number of the above-mentioned power units 103 is three, with an integrated power semiconductor module 1, an integrated power semiconductor module 2, and an integrated power semiconductor module 3. Moreover, when there are multiple power units 103, the power transformers connected by these multiple power units 103 can be the same power transformer.

[0066] In some embodiments of the present invention, the main controller 102 includes: a first comparator, the input end of the first comparator is adapted to be connected to the input end of the main controller 102, and the first comparator is used to obtain the current output voltage and obtain the voltage difference between the target output voltage and the current output voltage; an analog-to-digital converter, the input end of the analog-to-digital converter is connected to the output end of the first comparator, and the analog-to-digital converter is used to convert the voltage difference into a digital signal; a voltage loop digital compensator, the input end of the voltage loop digital compensator is connected to the output end of the analog-to-digital converter, and the voltage loop digital compensator is used to obtain an initial compensation signal according to the digital signal; a digital-to-analog converter, the input end of the digital-to-analog converter is connected to the output end of the voltage loop digital compensator, and the output end of the digital-to-analog converter is adapted to be connected to the output end of the main controller 102, and the digital-to-analog converter is used to convert the initial compensation signal into an analog signal to obtain a compensation signal.

[0067] Among them, for the above voltage loop digital compensator, see Figure 10 , which includes: a unit delay element 301, the unit delay element 301 is used to delay the received data by a preset time and output it; a first multiplier 302, the input end of the first multiplier 302 is adapted to be connected to the input end of the voltage loop digital compensator, and the first multiplier 302 is used to multiply the digital signal by a first preset parameter to obtain a first multiplication result; a second multiplier 303, the input end of the second multiplier 303 is adapted to be connected to the input end of the voltage loop digital compensator, and the second multiplier 303 is used to multiply the digital signal by a second preset parameter to obtain a second multiplication result; a first adder 304, the first input end of the first adder 304 is connected to the output end of the first multiplier 302, the second input end of the first adder 304 is connected to the output end of the unit delay element 301, and the output end of the first adder 304 is connected to the input end of the unit delay unit. The first adder 304 is used to add the first multiplication result and the output data of the unit delay element 301 to obtain a first addition result; an anti-saturation element 306, the input end of the anti-saturation element 306 is connected to the output end of the first adder, and the output end of the anti-saturation element 306 is connected to the input end of the unit delay element. The anti-saturation element 306 is used to obtain a correction signal according to the first addition result. Among them, when the first addition result is greater than or equal to a preset upper limit, the correction signal is the preset upper limit. When the first addition result is less than or equal to a preset lower limit, the correction signal is the preset lower limit. When the first addition result is greater than the preset lower limit and less than the preset upper limit, the correction signal is the first addition result; a second adder 305, the first input end of the second adder 305 is connected to the output end of the anti-saturation element 306, the second input end of the second adder 305 is connected to the output end of the second multiplier 303, and the output end of the second adder 305 is adapted to be connected to the output end of the voltage loop digital compensator. The second adder 305 is used to add the correction signal and the second multiplication result to obtain a second addition result, and use the second addition result as the initial compensation signal.

[0068] Through the above-mentioned Figure 10 shown voltage-loop digital compensator, after the k-th digital signal V(k) is input, U(k)=Up(k)+Ui(k)=Kp×V(k)+Ki×Ts×V(k)+Ui(k - 1) can be output.

[0069] Among them, V(k) is the k-th input data input to the first multiplier 302 and the second multiplier 303, U(k) is the k-th data output by the second adder 305, the above-mentioned Ki is the above-mentioned first preset parameter, the above-mentioned Kp is the above-mentioned second preset parameter, Ui(k - 1) is the correction signal output by the anti-saturation element 306 when the input data is V(k - 1), and Up(k) is the second multiplication result output by the second multiplier 303 when the input data is V(k). The above-mentioned Ts is the sampling period, and preferably the delay time of the unit delay element 301 is set to this Ts, that is, the above-mentioned preset time is preferably this Ts.

[0070] Both the above-mentioned first preset parameter Ki and the second preset parameter Kp are preset digital compensator gains, and their initial values are given by external programming, and then automatically calibrated through digital automatic adjustment according to the frequency response of the compensator.

[0071] In some embodiments of the present invention, the power unit controller includes: a second comparator, the input end of the second comparator is adapted to be connected to the second input end of the power unit controller, and the second comparator is used to obtain the current output current and obtain the current difference between the current output current and the target output current; a current-loop regulator, the input end of the current-loop regulator is connected to the output end of the second comparator, and the current-loop regulator is used to obtain a first initial signal according to the current difference; a third comparator, the first input end of the third comparator is connected to the output end of the current-loop regulator, the second input end of the third comparator is adapted to be connected to the first input end of the power unit controller, and the third comparator is used to obtain the difference between the compensation signal and the first initial signal and use the difference as the second initial signal; a PWM modulator, the input end of the PWM modulator is connected to the output end of the third comparator, the output end of the PWM modulator is adapted to be connected to the output end of the power unit controller, and the PWM modulator is used to obtain a PWM signal according to the second initial signal and use the PWM signal as the control signal.

[0072] The following combines Figure 11 the specific embodiments shown for specific description.

[0073] Specifically, referring to Figure 11 , in the main controller 102, it includes a first comparator, an analog-to-digital converter, a voltage-loop digital compensator, a digital-to-analog converter, and a current distributor, and the power unit controller includes a second comparator, a current-loop regulator, a third comparator, and a PWM modulator.

[0074] The main controller 102 is connected to the operation panel, which can be, for example, an operation and display panel that can be used for both operation and display. Through the operation panel, the main controller 102 can obtain the operation panel given voltage Vref and the operation panel given current I provided by the user through the operation panel. The operation panel given voltage Vref is the above-mentioned target output voltage.

[0075] Moreover, the first comparator also needs to implement the sampling and feedback of the total output voltage of the whole machine to obtain the current output voltage V(t), and the second comparator also needs to implement the sampling and feedback of the current in the power unit 103 to obtain the current output current I(t).

[0076] After obtaining the current output voltage and the target output voltage, the first comparator obtains the voltage difference between them. The analog-to-digital converter converts the voltage difference into a digital signal. The voltage loop digital compensator is used for compensation to obtain an initial compensation signal. The digital-to-analog converter then converts the initial compensation signal into an analog signal to obtain a compensation signal.

[0077] Moreover, for the above-mentioned operation panel given current I, after the current distributor in the main controller 102 receives the operation panel given current I, it also needs to determine the target output current according to the operation panel given current I. For example, assuming the number of power units 103 is one, the target output current can be set as the operation panel given current I. Assuming the number of power units 103 is two, the target output current can be set as half of the operation panel given current I. Of course, if the number of power units 103 is more, it can be deduced by analogy, and other distribution methods can also be adopted, as long as the sum of the currents output by each power unit 103 is the operation panel given current I. Of course, if a certain power unit 103 fails, the current distributor can distribute the current originally assigned to this power unit 103 to other power units 103.

[0078] For each power unit 103, after it receives the current output current I(t) and the corresponding target output current, the second comparator obtains the current difference. The current loop regulator obtains the first initial signal according to the current difference. The third comparator obtains the difference between the compensation signal and the first initial signal to obtain the second initial signal. The PWM modulator obtains the PWM signal according to the second initial signal and controls the switching tubes in the inverter sub-circuit 202 according to the PWM signal.

[0079] In some embodiments of the present invention, the main controller 102 is connected to the operation and display panel. The main controller 102 receives the operation panel given voltage and operation panel given current of the manual operation through the operation and display panel, outputs the real-time voltage and real-time current to the display panel, controls the torch switch, and controls the gas valve switch. Among them, the above-mentioned operation panel given voltage is the above-mentioned target output voltage, and the above-mentioned operation panel given current is the above-mentioned target output current.

[0080] After receiving the operation panel given current, the main controller 102 outputs it to each power unit controller through the current distributor.

[0081] The power unit controller is in signal connection with the main controller 102 and is also connected to the drive board in the corresponding power unit 103.

[0082] In a specific embodiment, see Figure 12 , in this example, the power supply circuit 100 is used for an electric welding machine. The main controller 102 is connected to the operation and display panel. The main controller 102 sends the current voltage information and current information to the operation and display panel so that the operation and display panel can display the voltage and current. The operation and display panel sends instructions to the main controller 102, including control instructions for the torch switch, welding voltage, and gas valve switch.

[0083] The main controller 102 is connected to the power unit controllers in each power unit 103 for communicating with the power unit controllers. The power unit controller is connected to the drive board and the integrated power semiconductor module for sending drive signals and receiving signals such as current signals, power unit temperature signals, and drive fault feedback signals.

[0084] In summary, for the power supply circuit of the embodiments of the present invention, through the setting of the power unit, the structural design of the power supply can be simplified, and the problem of complex assembly structure of the whole machine can be solved. Moreover, by combining digital control and analog control, the control parameters are optimized, the problem of difficult calibration of the control loop Kp and Ki parameters is solved, the control accuracy of the controller is improved, which is beneficial to achieving the best effect of the whole machine and making the control system less susceptible to interference. Moreover, by adopting the method of setting the integrated power semiconductor module, the power factor is improved, and the harmonic pollution of the inverter welding machine to the power grid is minimized.

[0085] Furthermore, the present invention proposes a power electronic power supply.

[0086] Figure 13 is the structural block diagram of the power electronic power supply of the embodiments of the present invention.

[0087] As Figure 13 shown, the power electronic power supply 400 includes the above-mentioned power supply circuit 100.

[0088] The power electronic power supply according to the embodiment of the present invention can simplify the structural design of the power supply through the power supply circuit of the above embodiment and the setting of the power unit, and solve the problem of complex assembly structure of the whole machine. Moreover, by combining digital control and analog control, the control parameters are optimized, the problem of difficult calibration of the Kp and Ki parameters of the control loop is solved, the control accuracy of the controller is improved, which is beneficial to achieving the best effect of the whole machine, and the control system is not easily interfered. Moreover, by setting the integrated power semiconductor module, the power factor is improved, and the harmonic pollution of the inverter welding machine to the power grid is minimized.

[0089] Further, the present invention provides a welding machine.

[0090] Figure 14 It is a structural block diagram of the welding machine according to the embodiment of the present invention.

[0091] As Figure 14 shown, the welding machine 500 includes the above-mentioned power electronic power supply 400.

[0092] The welding machine according to the embodiment of the present invention can simplify the structural design of the power supply through the power electronic power supply of the above embodiment and the setting of the power unit, and solve the problem of complex assembly structure of the whole machine. Moreover, by combining digital control and analog control, the control parameters are optimized, the problem of difficult calibration of the Kp and Ki parameters of the control loop is solved, the control accuracy of the controller is improved, which is beneficial to achieving the best effect of the whole machine, and the control system is not easily interfered. Moreover, by setting the integrated power semiconductor module, the power factor is improved, and the harmonic pollution of the inverter welding machine to the power grid is minimized.

[0093] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein can be considered as a definite sequence list of executable instructions for implementing logical functions, which can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in combination with an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium include the following: an electrical connection part with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or other suitable processing as necessary, and then stored in a computer memory.

[0094] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0095] In the description of this specification, the description referring to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0096] In the description of this specification, the orientation or positional relationship indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and does 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 should not be construed as a limitation of the present invention.

[0097] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0098] In the description of this specification, unless otherwise stated, the terms such as "mounted", "connected", "coupled", "fixed", etc. shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0099] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher horizontal height than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower horizontal height than the second feature.

[0100] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as a limitation of the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A power supply circuit, characterized in that, The circuit includes a power supply device, a main controller, and a power unit. The first input end of the power unit is connected to the power supply device. The first output end of the power unit is adapted to be connected to the output end of the power supply circuit. The input end of the main controller is connected to the output end of the power unit. The output end of the main controller is connected to the control end of the power unit. Among them, the main controller is used to obtain the current output voltage of the power unit and output a compensation signal according to the current output voltage and the target output voltage. The power unit is used to process the output voltage of the power supply device according to the compensation signal so that the output voltage of the power unit reaches the target output voltage.

2. The power supply circuit according to claim 1, wherein The power supply device is used to output alternating current. The circuit further includes a power transformer. The primary side of the power transformer is connected to the second output end of the power unit. The secondary side of the power transformer is connected to the second input end of the power unit. The power unit includes: an input rectifier circuit. The input end of the input rectifier circuit is adapted to be connected to the first input end of the power unit. The input rectifier circuit is used to convert the alternating current output by the power supply device into direct current. an inverter circuit. The input end of the inverter circuit is connected to the output end of the input rectifier circuit. The output end of the inverter circuit is adapted to be connected to the second output end of the power unit. The control end of the inverter circuit is adapted to be connected to the control end of the power unit. The inverter circuit is used to perform an inversion process on the direct current output by the input rectifier circuit according to the control signal output by the main controller. a full-wave rectifier circuit. The input end of the full-wave rectifier circuit is adapted to be connected to the second input end of the power unit. The output end of the full-wave rectifier circuit is adapted to be connected to the first output end of the power unit. The full-wave rectifier circuit is used to perform full-wave rectification on the output current of the power transformer.

3. The power supply circuit according to claim 2, wherein The power unit further includes: a power unit controller. The first input end of the power unit controller is adapted to be connected to the control end of the power unit. The second input end of the power unit controller is connected to the output end of the inverter circuit. The power unit controller is used to obtain the current output current of the inverter circuit and generate a control signal according to the current output current, the target output current, and the compensation signal. a drive board. The input end of the drive board is connected to the output end of the drive unit controller. The output end of the drive board is connected to the control end of the inverter circuit. The drive board is used to control the inverter circuit to perform an inversion process on the output voltage of the power supply device according to the control signal.

4. The power supply circuit according to claim 2, wherein, The input end of the inverter circuit is further adapted to be connected to the third input end of the power unit. The circuit further includes: a three-phase power factor correction sub-circuit. The input end of the three-phase power factor correction sub-circuit is connected to the output end of the power supply device. The output end of the three-phase power factor correction sub-circuit is connected to the third input end of the power unit. The three-phase power factor correction sub-circuit is used to perform power factor correction on the output of the power supply device.

5. The power supply circuit according to claim 3, characterized in that The main controller includes: A first comparator, wherein an input end of the first comparator is adapted to be connected to an input end of the main controller, and the first comparator is configured to obtain the current output voltage and obtain a voltage difference between the target output voltage and the current output voltage; An analog-to-digital converter, wherein an input end of the analog-to-digital converter is connected to an output end of the first comparator, and the analog-to-digital converter is configured to convert the voltage difference into a digital signal; A voltage-loop digital compensator, wherein an input end of the voltage-loop digital compensator is connected to an output end of the analog-to-digital converter, and the voltage-loop digital compensator is configured to obtain an initial compensation signal according to the digital signal; A digital-to-analog converter, wherein an input end of the digital-to-analog converter is connected to an output end of the voltage-loop digital compensator, an output end of the digital-to-analog converter is adapted to be connected to an output end of the main controller, and the digital-to-analog converter is configured to convert the initial compensation signal into an analog signal to obtain the compensation signal.

6. The power supply circuit according to claim 5, wherein The power unit controller includes: A second comparator, wherein an input end of the second comparator is adapted to be connected to a second input end of the power unit controller, and the second comparator is configured to obtain the current output current and obtain a current difference between the current output current and the target output current; A current-loop regulator, wherein an input end of the current-loop regulator is connected to an output end of the second comparator, and the current-loop regulator is configured to obtain a first initial signal according to the current difference; A third comparator, wherein a first input end of the third comparator is connected to an output end of the current-loop regulator, a second input end of the third comparator is adapted to be connected to a first input end of the power unit controller, and the third comparator is configured to obtain a difference between the compensation signal and the first initial signal and use the difference as a second initial signal; A PWM modulator, wherein an input end of the PWM modulator is connected to an output end of the third comparator, an output end of the PWM modulator is adapted to be connected to an output end of the power unit controller, and the PWM modulator is configured to obtain a PWM signal according to the second initial signal and use the PWM signal as the control signal.

7. The power supply circuit according to claim 5, wherein The voltage-loop digital compensator includes: A unit delay element, which is configured to delay the received data and output it after a preset time; A first multiplier, wherein an input end of the first multiplier is adapted to be connected to an input end of the voltage-loop digital compensator, and the first multiplier is configured to multiply the digital signal by a first preset parameter to obtain a first multiplication result; A second multiplier, wherein an input end of the second multiplier is adapted to be connected to an input end of the voltage-loop digital compensator, and the second multiplier is configured to multiply the digital signal by a second preset parameter to obtain a second multiplication result; A first adder, wherein a first input end of the first adder is connected to an output end of the first multiplier, an output end of the first adder is connected to an input end of the unit delay unit, and the first adder is configured to add the first multiplication result and the output data of the unit delay element to obtain a first addition result; An anti-saturation element, the input end of the anti-saturation element is connected to the output end of the first adder, the output end of the anti-saturation element is connected to the input end of the unit delay element, and the anti-saturation element is used to obtain a correction signal according to the first addition result, wherein when the first addition result is greater than or equal to a preset upper limit, the correction signal is the preset upper limit, when the first addition result is less than or equal to a preset lower limit, the correction signal is the preset lower limit, and when the first addition result is greater than the preset lower limit and less than the preset upper limit, the correction signal is the first addition result; A second adder, the first input end of the second adder is connected to the output end of the anti-saturation element, the second input end of the second adder is connected to the output end of the second multiplier, the output end of the second adder is adapted to be connected to the output end of the voltage loop digital compensator, and the second adder is used to add the correction signal and the second multiplication result to obtain a second addition result and use the second addition result as the initial compensation signal.

8. The power supply circuit according to claim 1, wherein The number of the power units is at least one.

9. A power electronic power supply, characterized in that, Comprising a power supply circuit according to any one of claims 1-8.

10. A welding machine, characterized in that, Comprising a power electronic power supply according to claim 9.

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