Driving circuit and laser wire feeding equipment

Abstract

The utility model provides a driving circuit and laser wire feeding equipment. The driving circuit comprises a bus voltage and current sampling module, a control module, a switch module and a full-bridge driving module, the first end of the switch module is connected with the first end of a direct-current power supply, the second end of the switch module is connected with the first end of the full-bridge driving module, the second end of the full-bridge driving module is connected with the second end of the direct-current power supply, and the third end of the full-bridge driving module is connected with the first end of the motor. The fourth end of the full-bridge driving module is used for being connected with the second end of the motor, the bus voltage and current sampling module is connected between the first end of the direct-current power source and the first end of the full-bridge driving module, and the control module is connected with the bus voltage and current sampling module, the switch module and the full-bridge driving module. The bus voltage and the bus current are acquired through the bus voltage and current sampling module, and the control module can control the switch-on or switch-off of the switch module based on the bus voltage and the bus current, so that overvoltage protection and overcurrent protection are realized, and the safety of the circuit is improved.

Description

Technical Field

[0001] The embodiments of the utility model relate to the field of electronic power technology, and in particular to a driving circuit and a laser wire feeding device. Background Art

[0002] The wire feeder is a vital device in the welding process, used to precisely control the delivery of welding wire or metal wire. In welding, the precise delivery of welding wire is essential for the connection and processing of materials. The wire feeder ensures the accuracy and stability of the welding process by controlling the speed and position of the welding wire. This equipment not only controls the speed of the welding wire, but also ensures the continuity and consistency of the welding wire during the welding process, thereby ensuring the quality of the welding. Through this precise control, the wire feeder can meet various welding needs, including the adaptation to different materials and welding environments, providing reliable technical support for welding operations.

[0003] At present, laser welding is gradually rising both at home and abroad, but the application of laser wire feeders is less and the technology is lacking. In the existing driving circuit of laser wire feeders, there is a lack of corresponding protection mechanism. For example, when the bus voltage or bus current is too large, the motor is always working, which may easily cause the motor to burn out and has poor safety. Utility Model Content

[0004] The embodiments of the utility model provide a driving circuit and a laser wire feeding device, which can improve the safety of the circuit.

[0005] In a first aspect, an embodiment of the utility model provides a drive circuit, which includes: a bus voltage and current sampling module, a control module, a switch module and a full-bridge drive module; the first end of the switch module is used to connect the first end of the DC power supply, the second end of the switch module is connected to the first end of the full-bridge drive module, the second end of the full-bridge drive module is used to connect the second end of the DC power supply, the third end of the full-bridge drive module is used to connect the first end of the motor, and the fourth end of the full-bridge drive module is used to connect the second end of the motor. The bus voltage and current sampling module is connected between the first end of the DC power supply and the first end of the full-bridge drive module, and the control module is respectively connected to the bus voltage and current sampling module, the control end of the switch module and the control end of the full-bridge drive module; wherein the bus voltage and current sampling module is used to obtain the bus voltage of the DC power supply and the bus current on the DC bus; the control module is used to control the conduction or disconnection of the switch module based on the bus voltage and the bus current to establish or disconnect the connection between the DC power supply and the full-bridge drive module to control the operation of the motor.

[0006] In some embodiments, the bus voltage and current sampling module includes a bus voltage sampling unit and a bus current sampling unit; the first end of the bus voltage sampling unit is respectively connected to the first end of the DC power supply and the first end of the switch module, the second end of the bus voltage sampling unit is connected to the second end of the DC power supply, and the third end of the bus voltage sampling unit is connected to the first end of the control module; the first end of the bus current sampling unit is connected to the second end of the switch module, the second end of the bus current sampling unit is connected to the first end of the full-bridge drive module, and the third end of the bus current sampling unit is connected to the second end of the control module; wherein the bus voltage sampling unit is used to output a bus sampling voltage to the control module based on the bus voltage, and the bus current sampling unit is used to output a sampling signal to the control module based on the bus current.

[0007] In some embodiments, the bus voltage sampling unit includes a resistor R5 and a resistor R6; the first end of the resistor R5 is respectively connected to the first end of the DC power supply and the first end of the switch module, the second end of the resistor R5 is respectively connected to the first end of the resistor R6 and the first end of the control module, and the second end of the resistor R6 is respectively connected to the second end of the DC power supply.

[0008] In some embodiments, the bus current sampling unit includes a resistor Rs, a resistor R1, a resistor R2, a resistor R3, a resistor R4 and an operational amplifier U1; the first end of the resistor Rs is respectively connected to the second end of the switch module and the first end of the resistor R1, the second end of the resistor Rs is respectively connected to the first end of the full-bridge drive module and the first end of the resistor R2, the second end of the resistor R1 is respectively connected to the first end of the resistor R3 and the first input end of the operational amplifier U1, the second end of the resistor R2 is respectively connected to the first end of the resistor R4 and the second input end of the operational amplifier U1, the second end of the resistor R3 is respectively connected to the ground, and the output end of the operational amplifier U1 is respectively connected to the second end of the resistor R4 and the second end of the control module.

[0009] In some embodiments, the drive circuit further includes a motor current sampling module; the motor current sampling module is connected to the third end of the control module; the motor current sampling module is used to output a motor sampling current to the control module based on the current flowing through the motor.

[0010] In some embodiments, the motor current sampling module includes a Hall sensor; the current path of the motor passes through the Hall sensor, and the Hall sensor is also connected to the third terminal of the control module.

[0011] In some embodiments, the driving circuit further includes an inductor L1; the inductor L1 is connected between the third terminal of the full-bridge driving module and the first terminal of the motor.

[0012] In some embodiments, the drive circuit also includes a motor voltage sampling module; the first end of the motor voltage sampling module is used to connect the first end of the motor, the second end of the motor voltage sampling module is used to connect the second end of the motor, and the third end of the motor voltage sampling module is connected to the fourth end of the control module; the motor voltage sampling module is used to output a motor sampling voltage to the control module based on the voltage between the first end of the motor and the second end of the motor.

[0013] In some embodiments, the motor voltage sampling module includes a resistor R7, a resistor R8, a resistor R9, a resistor R10, and an operational amplifier U2; the first end of the resistor R7 is used to connect to the first end of the motor, the first end of the resistor R8 is used to connect to the second end of the motor, the second end of the resistor R7 is respectively connected to the first end of the resistor R9 and the first input end of the operational amplifier U2, the second end of the resistor R8 is respectively connected to the first end of the resistor R10 and the second input end of the operational amplifier U2, the second end of the resistor R9 is grounded, and the output end of the operational amplifier U2 is respectively connected to the second end of the resistor R10 and the fourth end of the control module.

[0014] In a second aspect, an embodiment of the utility model provides a laser wire feeding device, which includes a motor and a driving circuit as described in any one of the embodiments of the first aspect; the driving circuit is connected to the motor.

[0015] Compared with the prior art, the utility model has the following beneficial effects: Different from the prior art, the utility model provides a driving circuit and a laser wire feeding device, including a bus voltage and current sampling module, a control module, a switch module and a full-bridge drive module; the first end of the switch module is used to connect the first end of the DC power supply, the second end of the switch module is connected to the first end of the full-bridge drive module, the second end of the full-bridge drive module is used to connect the second end of the DC power supply, the third end of the full-bridge drive module is used to connect the first end of the motor, the fourth end of the full-bridge drive module is used to connect the second end of the motor, the bus voltage and current sampling module is connected between the first end of the DC power supply and the first end of the full-bridge drive module, and the control module is respectively connected to the bus voltage and current sampling module, the switch module and the full-bridge drive module. The bus voltage and bus current are obtained through the bus voltage and current sampling module, and the control module can control the switch module to turn on or off based on the bus voltage and bus current, so as to realize overvoltage protection and overcurrent protection and improve the safety of the circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] One or more embodiments are exemplarily described by pictures in the corresponding drawings, and these exemplified descriptions do not constitute limitations on the embodiments. Elements / modules and steps with the same reference numerals in the drawings are represented as similar elements / modules and steps. Unless otherwise specified, the figures in the drawings do not constitute proportional limitations.

[0017] Figure 1 It is a structural block diagram of a driving circuit provided by an embodiment of the utility model;

[0018] Figure 2 It is a structural schematic diagram of a driving circuit provided by an embodiment of the utility model;

[0019] Figure 3 This is a working logic diagram of a driving circuit provided by an embodiment of the utility model;

[0020] Figure 4 It is a control logic schematic diagram of a control module provided by an embodiment of the utility model. DETAILED DESCRIPTION

[0021] The utility model is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the utility model, but do not limit the utility model in any form. It should be pointed out that for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the utility model. These all fall within the scope of protection of the utility model.

[0022] For ease of understanding of the present application, the present application is described in more detail below in conjunction with the accompanying drawings and specific embodiments. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those generally understood by those skilled in the art of the present application. The terms used in the specification of the present application are only for the purpose of describing specific embodiments and are not used to limit the present application. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0023] It should be noted that, if there is no conflict, the various features in the embodiments of the present utility model can be combined with each other, and all are within the scope of protection of this application. In addition, although the functional module division is performed in the device schematic, in some cases, the module division can be different from that in the device. In addition, the words "first", "second", etc. used in this article do not limit the data and execution order, but only distinguish the same items or similar items with basically the same functions and effects.

[0024] At present, laser welding has just emerged at home and abroad, and the application of laser wire feeders is relatively small. The technology is lacking. Open-loop wire feeding is usually used, and the speed is manually adjusted. When the laser wire feeding motor is overloaded, not only will the speed be slower, but the current will be too large. In the case of overload and short circuit, the motor is prone to burn out, and the drive circuit will also burn out.

[0025] In order to improve the safety of circuit operation, an embodiment of the utility model provides a driving circuit and a laser wire feeding device, which samples the bus voltage and bus current through a bus voltage and current sampling module and outputs them to a control module. The control module can control the on or off of the switch module based on the bus voltage and bus current to improve the safety and reliability of circuit operation.

[0026] In a first aspect, the present invention provides a driving circuit. Figure 1 The driving circuit 100 includes: a bus voltage and current sampling module 10, a control module 20, a switch module 30 and a full-bridge driving module 40.

[0027] The first end of the switch module 30 is used to connect to the first end of the DC power supply 200, the second end of the switch module 30 is connected to the first end of the full-bridge drive module 40, the second end of the full-bridge drive module 40 is used to connect to the second end of the DC power supply 200, the third end of the full-bridge drive module 40 is used to connect to the first end of the motor 300, the fourth end of the full-bridge drive module 40 is used to connect to the second end of the motor 300, the bus voltage and current sampling module 10 is connected between the first end of the DC power supply 200 and the first end of the full-bridge drive module 40, and the control module 20 is respectively connected to the bus voltage and current sampling module 10, the control end of the switch module 30 and the control end of the full-bridge drive module 40.

[0028] The bus voltage and current sampling module 10 is used to obtain the bus voltage of the DC power supply 200 and the bus current on the DC bus. The control module 20 is used to control the on or off of the switch module 30 based on the bus voltage and the bus current to establish or disconnect the connection between the DC power supply 200 and the full-bridge drive module 40 to control the operation of the motor 300.

[0029] The bus voltage is the voltage of the DC power supply 200. The DC bus is the wire connecting the DC power supply 200 and the full-bridge drive module 40, and the bus current is the current delivered by the DC power supply 200 to the full-bridge drive module 40. In the drive circuit 100, the bus voltage and bus current are obtained by the bus voltage and current sampling module 10, and the bus voltage and bus current are output to the control module 20. The control module 20 can control the conduction or shutdown of the switch module 30 based on the magnitude of the bus voltage and the bus current, so as to establish or disconnect the connection between the DC power supply 200 and the full-bridge drive module 40, so that the motor 300 is powered by the DC power supply 200, or the DC power supply 200 stops supplying power to the motor 300, so as to control the work of the motor 300.

[0030] Specifically, the bus voltage and current sampling module 10 obtains the bus voltage and outputs the bus voltage to the control module 20. The control module 20 controls the switch module 30 to be in the on state only when the bus voltage is in the normal range, that is, the connection between the DC power supply 200 and the full-bridge drive module 40 is established, and the full-bridge drive module 40 starts to drive the motor 300 to work. When the bus voltage is in an abnormal range, such as overvoltage or undervoltage, the control module 20 controls the switch module 30 to be in the off state. During the operation of the motor 300, the bus voltage and current sampling module 10 also obtains the bus current and outputs the bus current to the control module 20. When the bus current is in an abnormal range, such as overcurrent, the control module 20 controls the switch module 30 to be in the off state to disconnect the connection between the DC power supply 200 and the full-bridge drive module 40, thereby reducing the situation of unstable operation of hardware and overheating of components.

[0031] It can be seen that in the driving circuit 100 provided in this embodiment, the bus voltage and bus current are obtained through the bus voltage and current sampling module 10, and the control module 20 can control the on or off of the switch module 30 based on the bus voltage and bus current, thereby realizing overvoltage protection and overcurrent protection, solving the problem of burning of the motor and driving circuit when the subsequent wire feeding motor is overloaded or short-circuited, and improving the reliability and safety of the circuit operation.

[0032] In some of these examples, see Figure 2The bus voltage and current sampling module 10 includes a bus voltage sampling unit 11 and a bus current sampling unit 12. The first end of the bus voltage sampling unit 11 is respectively connected to the first end of the DC power supply 200 and the first end of the switch module 30, the second end of the bus voltage sampling unit 11 is connected to the second end of the DC power supply 200, and the third end of the bus voltage sampling unit 11 is connected to the first end of the control module 20. The first end of the bus current sampling unit 12 is connected to the second end of the switch module 30, the second end of the bus current sampling unit 12 is connected to the first end of the full-bridge drive module 40, and the third end of the bus current sampling unit 12 is connected to the second end of the control module 20. The bus voltage sampling unit 11 is used to output a bus sampling voltage to the control module 20 based on the bus voltage, and the bus current sampling unit 12 is used to output a sampling signal to the control module 20 based on the bus current.

[0033] In the drive circuit 100, the bus voltage is sampled by the bus voltage sampling unit 11, and the bus current is sampled by the bus current sampling unit 12. The subsequent control module 20 can determine whether the bus is overvoltage or undervoltage based on the bus sampling voltage, and determine whether the bus is overcurrent based on the magnitude of the bus sampling current. When overvoltage, undervoltage or overcurrent occurs, the switch module 30 is controlled to be turned off to disconnect the connection between the DC power supply 200 and the full-bridge drive module 40, so that the motor 300 stops working, thereby achieving overvoltage protection and overcurrent protection, and improving the safety and reliability of circuit operation.

[0034] In some of these embodiments, please continue to see Figure 2 The bus voltage sampling unit 11 includes a resistor R5, a resistor R6 and a capacitor C1. The first end of the resistor R5 is respectively connected to the first end of the DC power supply 200 and the first end of the switch module 30, the second end of the resistor R5 is respectively connected to the first end of the resistor R6, the first end of the capacitor C1 and the first end of the control module 20, and the second end of the resistor R6 is respectively connected to the second end of the DC power supply 200 and the second end of the capacitor C1.

[0035] In the bus voltage sampling unit 11, the resistor R5 and the resistor R6 form a voltage divider circuit, which can divide the voltage based on the input voltage of the DC power supply 200, and output a voltage divider signal (bus sampling voltage) to the control module 20. The control module 20 can then determine whether the bus voltage is within a normal range based on the voltage divider signal, and control the switch module 30 to disconnect when the bus voltage is overvoltage or undervoltage, thereby achieving bus voltage protection. At the same time, the capacitor C1 can filter the bus sampling voltage to improve the stability of signal transmission.

[0036] In addition, when the driving circuit 100 is subsequently applied to a laser wire feeding device, please refer to Figure 3When the laser wire feeding equipment is in the circuit self-starting stage or standby stage, the bus current sampling unit 12 outputs the bus sampling voltage to the control module 20. The control module 20 judges the bus sampling voltage to determine whether the input voltage of the DC power supply 200 is less than the upper threshold and greater than the lower threshold. If so, the switch module 30 is controlled to be turned on, the full-bridge drive module 40 is powered, and the motor 300 starts working. If the input voltage of the DC power supply 200 is greater than or equal to the upper threshold and lasts for more than 100ms, the control module 20 determines that the current power supply is abnormal, controls the switch module 30 to be turned off, and implements bus voltage protection until the input voltage of the DC power supply 200 returns to the normal range. The control module 20 will release the bus voltage protection, control the switch module 30 to be turned on, and the system will continue to complete self-starting. Moreover, during the circuit operation stage, such as in the subsequent wire feeding process, if it is determined based on the bus sampling voltage that the bus voltage is over-voltage or under-voltage for more than 100ms, the control module 20 will determine that the current power supply is abnormal, and immediately and synchronously shut down the PWM output and the switch module 30 to protect the system from potential damage. After the power supply voltage condition returns to the set normal working range, the bus voltage protection mechanism will be automatically released and restored to the standby state. That is, if the bus voltage protection is triggered during the wire feeding process, the system will not automatically continue to feed the wire even after the obstacle that triggered the voltage protection is removed.

[0037] In some of these examples, see Figure 2 The bus current sampling unit 12 includes a resistor Rs, a resistor R1, a resistor R2, a resistor R3, a resistor R4 and an operational amplifier U1. The first end of the resistor Rs is respectively connected to the second end of the switch module 30 and the first end of the resistor R1, the second end of the resistor Rs is respectively connected to the first end of the full-bridge drive module 40 and the first end of the resistor R2, the second end of the resistor R1 is respectively connected to the first end of the resistor R3 and the first input end of the operational amplifier U1, the second end of the resistor R2 is respectively connected to the first end of the resistor R4 and the second input end of the operational amplifier U1, the second end of the resistor R3 is respectively connected to ground, and the output end of the operational amplifier U1 is respectively connected to the second end of the resistor R4 and the second end of the control module 20.

[0038] In this embodiment, the resistor Rs is usually a milliohm resistor. After being amplified by the operational amplifier, the current flowing through the resistor Rs will be converted into a voltage signal and output to the control module 20. The control module 20 can determine the bus current size based on the voltage signal, and when the bus current is overcurrent, control the switch module 30 to disconnect to achieve overcurrent protection.

[0039] Specifically, after the switch module 30 is turned on, the bus sampling unit outputs the sampled voltage signal to the control module in real time. The control module 20 determines the bus current based on the voltage signal. If the bus current exceeds the maximum current limit within 10 ms, the control module 20 controls the switch module 30 to disconnect and terminates the PWM output to the full-bridge drive module 40 to prevent unstable hardware operation and overheating of components and achieve overcurrent protection.

[0040] In some of these examples, see Figure 2 The switch module 30 may include a switch tube Q5, a first end of the switch tube Q5 is respectively connected to the first end of the DC power supply 200 and the first end of the resistor R5, a second end of the switch tube Q5 is connected to the first end of the resistor Rs, and a third end of the switch tube Q5 is connected to the control module 20. In this embodiment, the switch tube Q5 can be turned off or on based on the control signal of the control module 20.

[0041] In some of these embodiments, please continue to see Figure 2 The full-bridge driving module 40 includes a switch tube Q1, a switch tube Q2, a switch tube Q3 and a switch tube Q4; wherein the first ends of the switch tubes Q1 and Q4 are both connected to the second end of the resistor Rs, the second end of the switch tube Q1 is respectively connected to the first end of the motor 300 and the first end of the switch tube Q3, the second end of the switch tube Q4 is respectively connected to the second end of the motor 300 and the first end of the switch tube Q2, the second end of the switch tube Q3 and the second end of the switch tube Q4 are both connected to the second end of the DC power supply 200, and the third ends of the switch tubes Q1, Q2, Q3 and Q4 are all connected to the control module 20.

[0042] In this embodiment, the switch tubes Q1, Q2, Q3 and Q4 form an H-bridge circuit, which can drive the motor 300 to work based on the PWM output of the control module 20. The specific working principle can refer to the existing technology and will not be repeated here.

[0043] In some of these examples, see Figure 2 The driving circuit also includes a capacitor C2, which is connected between the second end of the resistor Rs and the second end of the DC power supply 200. The capacitor C2 is used for filtering to improve the stability of the circuit operation.

[0044] In some of these embodiments, please continue to see Figure 2 The drive circuit 100 further includes a motor current sampling module 50 . The motor current sampling module 50 is connected to the third terminal of the control module 20 ; the motor current sampling module 50 is used to output a sampled current of the motor 300 to the control module 20 based on the current flowing through the motor 300 .

[0045] In this embodiment, during the operation of the motor 300, the motor current sampling module 50 also outputs the motor 300 sampling current to the control module 20. When the control module 20 determines whether the current flowing through the motor 300 is in an abnormal range based on the motor 300 sampling current, such as when it exceeds the peak current protection threshold, the control module 20 controls the switch module 30 to be in an off state to disconnect the connection between the DC power supply 200 and the full-bridge drive module 40, thereby realizing motor overcurrent protection and improving the reliability and safety of the circuit operation.

[0046] Specifically, in some embodiments, the motor current sampling module 50 includes a Hall sensor. The current path of the motor 300 passes through the Hall sensor, and the Hall sensor is also connected to the third terminal of the control module 20. Figure 2 In the illustrated embodiment, the wire connected between the second end of the motor 300 and the second end of the switch tube Q4 can be passed through a Hall sensor. When the motor 300 is working, the Hall sensor will output a signal to the control module 20. The control module 20 can determine whether the current flowing through the motor 300 is in an abnormal range based on the output signal of the Hall sensor. If the motor current sampling value exceeds the current protection point for 10 ms continuously, the control module 20 will immediately stop the PWM output and control the switch module 30 to be in the off state to prevent the abnormal operation of the H-bridge from causing the field effect tube to break down, thereby achieving motor current protection.

[0047] In some of these examples, see Figure 2 , the driving circuit 100 also includes an inductor L1. The inductor L1 is connected between the third end of the full-bridge driving module 40 and the first end of the motor 300. Specifically, the first end of the inductor L1 is connected to the second end of the switch tube Q1 and the first end of the switch tube Q3 respectively. In the driving circuit 100, the inductor L1 can be used to suppress the sudden change of current. For example, when the motor 300 is short-circuited, the H-bridge drive still works at this time, and the current flowing through the H-bridge is large, which is easy to burn the field effect tube. The inductor L1 can effectively suppress the current rise rate per unit time (di / dt) and improve the safety and reliability of the circuit operation.

[0048] In some of these embodiments, please continue to see Figure 2 The drive circuit 100 further includes a motor voltage sampling module 60. A first end of the motor voltage sampling module 60 is used to connect to a first end of the motor 300, a second end of the motor voltage sampling module 60 is used to connect to a second end of the motor 300, and a third end of the motor voltage sampling module 60 is connected to a fourth end of the control module 20. The motor voltage sampling module 60 is used to output a sampled voltage of the motor 300 to the control module 20 based on a voltage between the first end of the motor 300 and the second end of the motor 300.

[0049] In this embodiment, during the operation of the motor 300, the motor voltage sampling module 60 also samples the voltage across the motor 300 and outputs the sampled voltage of the motor 300 to the control module 20. When the control module 20 determines whether the voltage across the motor 300 is in an abnormal range based on the sampled voltage of the motor 300, such as overvoltage or undervoltage, the control module 20 controls the switch module 30 to be in an off state to disconnect the connection between the DC power supply 200 and the full-bridge drive module 40, thereby realizing overvoltage protection of the motor 300 and improving the reliability and safety of the circuit operation.

[0050] In some of these examples, see Figure 2 The motor voltage sampling module 60 includes a resistor R7, a resistor R8, a resistor R9, a resistor R10, and an operational amplifier U2. The first end of the resistor R7 is used to connect to the first end of the motor 300, the first end of the resistor R8 is used to connect to the second end of the motor 300, the second end of the resistor R7 is respectively connected to the first end of the resistor R9 and the first input end of the operational amplifier U2, the second end of the resistor R8 is respectively connected to the first end of the resistor R10 and the second input end of the operational amplifier U2, the second end of the resistor R9 is grounded, and the output end of the operational amplifier U2 is respectively connected to the second end of the resistor R10 and the fourth end of the control module 20.

[0051] Usually, the voltage across the motor 300 is relatively large. In this embodiment, the voltage across the motor 300 is reduced by an operational amplifier through differential sampling and then output to the control module 20. The control module 20 can determine the motor current based on the output signal to achieve corresponding control.

[0052] In a second aspect, an embodiment of the utility model provides a laser wire feeding device, which includes a motor and a driving circuit as described in any one of the embodiments of the first aspect; the driving circuit is connected to the motor.

[0053] In this embodiment, the driving circuit has the same structure and function as the driving circuit described in any one of the first aspects, which will not be described in detail here. The laser wire feeding device is a device that uses the laser emitted by a laser as an energy source to melt metal powder or wire layer by layer and deposit it on the surface of the workpiece.

[0054] In addition, the control module in the drive circuit can use closed-loop control to operate the motor, for example Figure 4As shown, the calibrated actual speed and the set target speed are used as the main control input, and the PWM duty cycle output to the full-bridge drive module is automatically adjusted by the PID controller to control the driving voltage of the motor so that the actual speed of the motor gradually approaches the target speed. It is also possible to participate in the current closed-loop control of the motor based on the output signal of the Hall sensor, such as the control module continuously monitoring the deviation between the actual motor current and the target motor current, and automatically adjusting through the PID controller to ensure the stability and efficiency of the motor operation. Further, the control module can also correct the PID loop parameters based on feedback information such as the motor voltage, motor current, and real-time speed calculated by the algorithm model to optimize the dynamic performance of the motor. Compared with the manual adjustment method, the above method uses the controller to automatically control, which can reduce the speed inconsistency caused by different welding wire weights and different welding wire diameters during use, and improve the accuracy of motor control.

[0055] It should be noted that the device embodiments described above are merely illustrative, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Under the idea of ​​the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A driving circuit, characterized in that: include: Bus voltage and current sampling module, control module, switch module and full-bridge drive module; The first end of the switch module is used to connect to the first end of the DC power supply, the second end of the switch module is connected to the first end of the full-bridge drive module, the second end of the full-bridge drive module is used to connect to the second end of the DC power supply, the third end of the full-bridge drive module is used to connect to the first end of the motor, the fourth end of the full-bridge drive module is used to connect to the second end of the motor, the bus voltage and current sampling module is connected between the first end of the DC power supply and the first end of the full-bridge drive module, and the control module is respectively connected to the bus voltage and current sampling module, the control end of the switch module and the control end of the full-bridge drive module; Wherein, the bus voltage and current sampling module is used to obtain the bus voltage of the DC power supply and the bus current on the DC bus; The control module is used to control the on or off of the switch module based on the bus voltage and the bus current to establish or disconnect the connection between the DC power supply and the full-bridge drive module to control the operation of the motor.

2. The driving circuit according to claim 1, characterized in that: The bus voltage and current sampling module includes a bus voltage sampling unit and a bus current sampling unit; The first end of the bus voltage sampling unit is connected to the first end of the DC power supply and the first end of the switch module respectively, the second end of the bus voltage sampling unit is connected to the second end of the DC power supply, and the third end of the bus voltage sampling unit is connected to the first end of the control module; The first end of the bus current sampling unit is connected to the second end of the switch module, the second end of the bus current sampling unit is connected to the first end of the full-bridge drive module, and the third end of the bus current sampling unit is connected to the second end of the control module; The bus voltage sampling unit is used to output a bus sampling voltage to the control module based on the bus voltage, and the bus current sampling unit is used to output a sampling signal to the control module based on the bus current.

3. The driving circuit according to claim 2, characterized in that: The bus voltage sampling unit includes a resistor R5 and a resistor R6; The first end of the resistor R5 is respectively connected to the first end of the DC power supply and the first end of the switch module, the second end of the resistor R5 is respectively connected to the first end of the resistor R6 and the first end of the control module, and the second end of the resistor R6 is respectively connected to the second end of the DC power supply.

4. The driving circuit according to claim 2, characterized in that: The bus current sampling unit includes a resistor Rs, a resistor R1, a resistor R2, a resistor R3, a resistor R4 and an operational amplifier U1; The first end of the resistor Rs is respectively connected to the second end of the switch module and the first end of the resistor R1, the second end of the resistor Rs is respectively connected to the first end of the full-bridge drive module and the first end of the resistor R2, the second end of the resistor R1 is respectively connected to the first end of the resistor R3 and the first input end of the operational amplifier U1, the second end of the resistor R2 is respectively connected to the first end of the resistor R4 and the second input end of the operational amplifier U1, the second end of the resistor R3 is grounded, and the output end of the operational amplifier U1 is respectively connected to the second end of the resistor R4 and the second end of the control module.

5. The driving circuit according to any one of claims 1 to 4, characterized in that: The driving circuit also includes a motor current sampling module; The motor current sampling module is connected to the third terminal of the control module; The motor current sampling module is used to output a motor sampling current to the control module based on the current flowing through the motor.

6. The driving circuit according to claim 5, characterized in that: The motor current sampling module includes a Hall sensor; The current path of the motor passes through the Hall sensor, and the Hall sensor is also connected to the third terminal of the control module.

7. The driving circuit according to any one of claims 1 to 4, characterized in that: The driving circuit also includes an inductor L1; The inductor L1 is connected between the third terminal of the full-bridge driving module and the first terminal of the motor.

8. The driving circuit according to any one of claims 1 to 4, characterized in that: The driving circuit also includes a motor voltage sampling module; The first end of the motor voltage sampling module is used to connect to the first end of the motor, the second end of the motor voltage sampling module is used to connect to the second end of the motor, and the third end of the motor voltage sampling module is connected to the fourth end of the control module; The motor voltage sampling module is used to output a motor sampling voltage to the control module based on a voltage between a first end of the motor and a second end of the motor.

9. The driving circuit according to claim 6, characterized in that: The motor voltage sampling module includes a resistor R7, a resistor R8, a resistor R9, a resistor R10, and an operational amplifier U2; The first end of the resistor R7 is used to connect to the first end of the motor, the first end of the resistor R8 is used to connect to the second end of the motor, the second end of the resistor R7 is respectively connected to the first end of the resistor R9 and the first input end of the operational amplifier U2, the second end of the resistor R8 is respectively connected to the first end of the resistor R10 and the second input end of the operational amplifier U2, the second end of the resistor R9 is grounded, and the output end of the operational amplifier U2 is respectively connected to the second end of the resistor R10 and the fourth end of the control module.

10. A laser wire feeding device, characterized in that: Comprising a motor and a driving circuit as claimed in any one of claims 1 to 9; The driving circuit is connected to the motor.

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