CN114289828A - Blocking circuit and welding machine - Google Patents
Blocking circuit and welding machine Download PDFInfo
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- CN114289828A CN114289828A CN202111485971.6A CN202111485971A CN114289828A CN 114289828 A CN114289828 A CN 114289828A CN 202111485971 A CN202111485971 A CN 202111485971A CN 114289828 A CN114289828 A CN 114289828A
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- 238000003466 welding Methods 0.000 title claims abstract description 90
- 230000000903 blocking effect Effects 0.000 title claims abstract description 64
- 238000004146 energy storage Methods 0.000 claims abstract description 35
- 239000003990 capacitor Substances 0.000 claims description 30
- 238000000034 method Methods 0.000 description 18
- 230000008569 process Effects 0.000 description 18
- 239000004568 cement Substances 0.000 description 13
- 238000010586 diagram Methods 0.000 description 11
- 238000007599 discharging Methods 0.000 description 9
- 230000009471 action Effects 0.000 description 3
- 239000002360 explosive Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 210000003739 neck Anatomy 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
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- 238000006467 substitution reaction Methods 0.000 description 1
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Abstract
The application discloses blocking circuit and welding machine, this blocking circuit is used for being connected with the secondary side of transformer, and this blocking circuit includes energy storage unit, switch element, afterflow unit, discharge unit and welding unit. The energy storage unit is respectively connected with the secondary side, the switch unit, the welding unit and the follow current unit, the follow current unit is respectively connected with the discharge unit and the secondary side, and the discharge unit is connected with the welding unit. The energy storage unit is used for storing the first part of electric energy output by the discharge unit when the switch unit is turned off so as to reduce the current flowing through the welding unit. The follow current unit is used for storing the second part of electric energy output by the discharge unit when the switch unit is turned off and providing follow current for the welding unit based on the second part of electric energy. Through the mode, the risk of arc breakage can be reduced, and the working stability of the welding machine is improved.
Description
Technical Field
The application relates to the technical field of electronic circuits, in particular to a blocking circuit and a welding machine.
Background
In general, when a droplet is constricted in a direct current welding process, a very strong explosive force is generated due to excessive current, the explosive force is in a square relation with a current value at the moment, the explosive force is in a direct proportion with spatter, and if the spatter in the welding process is reduced, the current needs to be reduced to a very small value within 100us before the droplet is constricted. Due to the large system inductance, it is difficult to reduce the current to a small value within 100us by loop control. It is therefore necessary to force the current to a small value in a short time by means of a blocking circuit for the secondary current.
At present, a current blocking circuit of a secondary side of a commonly used welding machine is shown in fig. 1, and when a system detects that a molten drop necking comes in a welding process, the IGBT module Q101 is controlled to be turned off. At the moment, due to the follow current function of the output inductor of the welding system, the current is transferred from the original IGBT module Q101 to the high-power cement resistor R101, and due to the consumption of the high-power cement resistor R101 on the current energy, the large current during necking is changed into small current in a short time, so that the splashing reduction effect is realized.
However, the current of the scheme in the later stage of the blocking is small, and the arc breaking phenomenon is easy to occur in the process of realizing the blocking.
Disclosure of Invention
The embodiment of the application aims to provide a blocking circuit and a welding machine, which can reduce the risk of arc breakage and improve the working stability of the welding machine.
To achieve the above object, in a first aspect, the present application provides a blocking circuit for connecting with a secondary side of a transformer, the blocking circuit comprising:
the device comprises an energy storage unit, a switch unit, a follow current unit, a discharge unit and a welding unit;
the first end of the energy storage unit is connected with the first end of the secondary side and the first end of the switch unit, the second end of the energy storage unit is connected with the second end of the switch unit and the first end of the welding unit, the third end of the energy storage unit is connected with the first end of the follow current unit, the second end of the follow current unit is connected with the first end of the discharge unit and the second end of the secondary side, and the second end of the discharge unit is connected with the second end of the welding unit;
the energy storage unit is used for storing the first part of electric energy output by the discharge unit when the switch unit is turned off so as to reduce the current flowing through the welding unit;
the follow current unit is used for storing the second part of electric energy output by the discharge unit when the switch unit is turned off and providing follow current for the welding unit based on the second part of electric energy.
In an optional mode, the energy storage unit comprises a first capacitor and a first diode;
the first end of the first capacitor is connected with the first end of the secondary side and the first end of the switch unit, the second end of the first capacitor is connected with the anode of the first diode and the first end of the follow current unit, and the cathode of the first diode is connected with the second end of the switch unit and the first end of the welding unit.
In an optional mode, the blocking circuit further comprises a control unit, and the switching unit comprises a switching tube;
the first end of the switch tube is connected with the control unit, the third end of the switch tube is connected with the first end of the first capacitor, and the second end of the switch tube is connected with the cathode of the first diode;
the control unit is used for controlling the on or off of the switch tube.
In an optional manner, the control unit is specifically configured to:
acquiring the voltage at two ends of the first capacitor;
and when the voltage at the two ends of the first capacitor is greater than a first voltage threshold value, controlling the switch tube to be conducted.
In an alternative mode, the discharge unit includes a first inductor;
the first end of the first inductor is connected with the second end of the secondary side and the second end of the follow current unit, and the second end of the first inductor is connected with the second end of the welding unit.
In an optional mode, the freewheeling unit comprises a second inductor and a second diode;
the first end of the second inductor is connected with the anode of the second diode, the second end of the second inductor is connected with the first end of the first inductor, and the cathode of the second diode is connected with the third end of the energy storage unit.
In an optional manner, an inductance value of the first inductor is smaller than an inductance value of the second inductor.
In an alternative form, the welding unit comprises a welding arc;
the first end of the welding arc is connected with the second end of the switch unit and the second end of the energy storage unit, and the second end of the welding arc is connected with the second end of the discharge unit.
In an optional mode, the blocking circuit further comprises a third diode and a fourth diode;
the anode of the third diode is connected with the first end of the secondary side, the cathode of the third diode is connected with the cathode of the fourth diode, the first end of the energy storage unit and the first end of the switch unit, and the anode of the fourth diode is connected with the third end of the secondary side;
the third diode and the fourth diode are used for rectifying the voltage output by the secondary side.
In a second aspect, the present application provides a weld comprising a transformer and a blocking circuit as described above;
the blocking circuit is connected with the secondary side of the transformer.
The beneficial effects of the embodiment of the application are that: the blocking circuit is used for being connected with the secondary side of the transformer and comprises an energy storage unit, a switch unit, a follow current unit, a discharging unit and a welding unit. The energy storage unit is respectively connected with the secondary side, the switch unit, the welding unit and the follow current unit, the follow current unit is respectively connected with the discharge unit and the secondary side, and the discharge unit is connected with the welding unit. When the switch unit is turned off, the energy storage unit stores the first part of electric energy output by the discharge unit so as to reduce the current flowing through the welding unit, and meanwhile, the follow current unit stores the second part of electric energy output by the discharge unit and provides follow current for the welding unit according to the second part of electric energy. Therefore, if the welding unit is a welding arc, the function of blocking can be realized, and follow current is provided for the arc in the blocking process, so that the probability of arc breakage is reduced, namely, the risk of arc breakage is reduced, and the stability of the work of the welding machine is improved.
Drawings
One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.
Fig. 1 is a schematic circuit diagram of a current blocking circuit in the related art;
FIG. 2 is a schematic diagram of signals of the current block circuit shown in FIG. 1 in operation according to the related art;
fig. 3 is a schematic structural diagram of a blocking circuit according to an embodiment of the present disclosure;
fig. 4 is a schematic circuit diagram of a blocking circuit according to an embodiment of the present disclosure;
FIG. 5 is a schematic diagram of signals of the blocking circuit shown in FIG. 4 during operation according to an embodiment of the present application;
fig. 6 is a schematic diagram of an output voltage and an output current of the blocking circuit shown in fig. 4 according to an embodiment of the present disclosure.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
Referring to fig. 1, fig. 1 is a circuit structure diagram of a current blocking circuit in the related art. As shown in fig. 1, the current blocking circuit is used for connection to the secondary side of a transformer T101, and includes diodes D101 and D102 for rectification, an IGBT module Q101, a diode D103, a high power cement resistor R101 for consuming current when constricted, an inductor L101 capable of discharging when constricted, and an arc PWL101 for welding.
Please refer to fig. 1 and fig. 2 together, wherein fig. 2 is a schematic diagram of signals of the current blocking circuit shown in fig. 1 in the related art during operation. In gas metal arc welding, there is a phase of droplet transfer, in which a droplet constriction is formed. In fig. 2, a curve L201 is an output current of the current blocking circuit; a curve L202 is a control signal of the IGBT module Q101; a curve L203 is the output voltage of the current blocking circuit; time t201 is the time at which necking of the droplet starts. As can be seen from fig. 2, when droplet constriction occurs, at time t201, the control signal of the IGBT module Q101 is a low level signal, and the IGBT module Q101 is turned off. At this time, the inductor L101 can output a current due to the freewheeling action of the inductor L101, and the current output from the inductor L101 flows through the high-power cement resistor R101 after passing through the secondary side of the transformer T101 and the diode D101. The high-power cement resistor R101 can consume the current output by the inductor L101 to reduce the large current output by the inductor L101 to a smaller current in a short time, thereby implementing the blocking process.
However, in the process of implementing the present application, the inventors of the present application found that: the solutions in the related art have the following five disadvantages: firstly, at the later stage of the blocking process, the current flowing through the arc is too small, which easily causes the arc breaking phenomenon. Secondly, due to the characteristics that the turn-off time of the IGBT module Q101 is different, and the equivalent inductance of the commonly used high-power cement resistor R101 is relatively large, a spike high voltage is easily generated when the current is blocked (as can be seen from the curve L203, a spike voltage is generated after the time t 201), and the IGBT module Q101 may be damaged due to overvoltage. Third, to reduce the probability of arc interruption, a relatively high no-load voltage and a relatively large inductance L101 are typically employed to increase the current provided to the arc, however, this results in increased cost. Fourth, in order to reduce the probability of over-voltage damage to the IGBT module Q101, a high-voltage IGBT module must be used, which also increases the cost significantly. Fifthly, the high-power cement resistor R101 is used for consuming the current generated during blocking, which results in a large amount of heat generated by the high-power cement resistor R101, i.e., the heat is generated seriously, and the electronic components are easily damaged.
Based on this, this application provides a blocking circuit, this blocking circuit through setting up the afterflow unit to realize in the process of blocking, reduce the risk that welding unit appears the broken arc. Secondly, the high-power cement resistor is not arranged, namely, the peak voltage generated by the equivalent inductance of the high-power cement resistor does not exist, so that the risk of overvoltage breakdown of the switch unit is low, and the system reliability is high. Meanwhile, because the risk of arc breakage is low, the high no-load voltage and the large inductance L101 are not needed, and the cost is low.
Referring to fig. 3, fig. 3 is a schematic structural diagram of a blocking circuit according to an embodiment of the present disclosure. As shown in fig. 3, the blocking circuit 100 is configured to be connected to the secondary side of the transformer T1, and the blocking circuit 100 includes an energy storage unit 10, a switching unit 20, a freewheeling unit 30, a discharging unit 40, and a welding unit 50. Specifically, a first end of the energy storage unit 10 is connected to a first end of the secondary side of the transformer T1 and a first end of the switching unit 20, a second end of the energy storage unit 10 is connected to a second end of the switching unit 20 and a first end of the welding unit 50, a third end of the energy storage unit 10 is connected to a first end of the freewheeling unit 30, a second end of the freewheeling unit 30 is connected to a first end of the discharging unit 40 and a second end of the secondary side of the transformer T1, and a second end of the discharging unit 40 is connected to a second end of the welding unit 50.
The energy storage unit 10 is configured to store a first portion of the electric energy output by the discharge unit 40 when the switching unit 20 is turned off, so as to reduce the current flowing through the welding unit 50. The freewheeling unit 30 is configured to store the second portion of the electrical energy output by the discharging unit 40 when the switching unit 20 is turned off, and provide a freewheeling for the welding unit 50 based on the second portion of the electrical energy.
In practical applications, when the switching unit 20 is turned off, the discharging unit 40 discharges. At this time, on one hand, the first part of the electric energy output by the discharge unit 40 is stored by the energy storage unit 10, so that the current flowing through the welding unit 50 is reduced, thereby protecting the welding unit 50 and preventing the welding current 50 from being damaged due to the excessive current flowing through the welding unit. On the other hand, the second part of the electric energy output by the discharging unit 40 is stored by the freewheeling unit 30, and then the freewheeling unit 30 provides a freewheeling for the welding unit 50 according to the second part of the electric energy. It can be seen that when the welding unit 50 is a welding arc, the current can be reduced by the energy storage unit 10 for the purpose of blocking. Meanwhile, the follow current unit 30 can provide follow current for the welding arc in the blocking process so as to reduce the probability of arc breakage, namely, the risk of arc breakage is reduced, and even if the follow current unit 30 is in the blocking later stage, the probability of arc breakage is reduced through the follow current effect of the follow current unit 30, and the stability of the work of the welding machine is improved.
In one embodiment, as shown in fig. 4, the energy storage unit 10 includes a first capacitor C1 and a first diode D1. A first end of the first capacitor C1 is connected to the first end of the secondary side of the transformer T1 and the first end of the switch unit 20, a second end of the first capacitor C1 is connected to the anode of the first diode D1 and the first end of the freewheel unit 30, and a cathode of the first diode D1 is connected to the second end of the switch unit 20 and the first end of the welding unit 50.
Specifically, when the discharge unit 40 is discharged, the first capacitor C1 is charged, i.e., the first part of the electrical energy output by the discharge unit 40 is stored, thereby reducing the current in the electrical circuit, i.e., the current flowing through the welding unit 50. The first diode D1 can prevent the first capacitor C1 from discharging through a loop formed by the first and second terminals of the switch unit 20 to damage the switch unit 20 when the switch unit 20 is turned on.
In an embodiment, the blocking circuit 100 further includes a control unit (not shown), and the switching unit 20 includes a switching tube Q1. The first end of the switching tube Q1 is connected to the control unit, the third end of the switching tube Q1 is connected to the first end of the first capacitor C1, the second end of the switching tube Q1 is connected to the cathode of the first diode D1, and the control unit is configured to control the switching tube Q1 to be turned on or off.
In this embodiment, the switch Q1 is exemplified by an IGBT switch. The gate of the IGBT switch tube is the first end of the switch tube Q1, the emitter of the IGBT switch tube is the second end of the switch tube Q1, and the collector of the IGBT switch tube is the third end of the switch tube Q1.
Specifically, when the control unit outputs a high-level signal, and the voltage of the high-level signal is greater than the turn-on voltage of the IGBT, the IGBT is turned on; on the contrary, when the control unit outputs a low level signal and the voltage of the low level signal is less than the turn-on voltage of the IGBT, the IGBT is turned off.
It should be noted that the switch Q1 may be any controllable switch, such as an Insulated Gate Bipolar Transistor (IGBT) device, an Integrated Gate Commutated Thyristor (IGCT) device, a gate turn-off thyristor (GTO) device, a Silicon Controlled Rectifier (SCR) device, a junction gate field effect transistor (JFET) device, a MOS Controlled Thyristor (MCT) device, etc. Meanwhile, the switching tube Q1 shown in fig. 4 may be implemented as a plurality of switches connected in parallel.
In an embodiment, the control unit is specifically configured to: the voltage across the first capacitor C1 is obtained. When the voltage across the first capacitor C1 is greater than the first voltage threshold, the switching tube Q1 is controlled to be turned on.
The first voltage threshold may be set according to an actual application, which is not limited in the embodiment of the present application. In an embodiment, the first voltage threshold may be set according to the type of the switching tube Q1, for example, if the switching tube Q1 is an IGBT switching tube with a voltage withstanding value of 650 v, the first voltage threshold may be set to a value smaller than 650 v, such as 450 v.
In this embodiment, by obtaining the voltage across the first capacitor C1 and controlling the switching transistor Q1 to turn off when the voltage is greater than the first voltage threshold, the voltage between the second terminal and the third terminal of the switching transistor Q1 can be effectively controlled below a small voltage, and the switching transistor Q1 with a low withstand voltage value can be selected, which is beneficial to reducing the cost. For example, in one embodiment, for the circuit structure shown in fig. 1, the IGBT module Q101 with a voltage withstanding value of 1200 v is usually selected, and for the present application, the switching transistor Q1 may be a 650 v IGBT switching transistor, and the cost of the switching transistor Q1 is lower than that of the IGBT module Q101 with a voltage withstanding value of 1200 v.
In addition, by selecting the switching tube Q1 with a lower voltage withstanding value, the conduction voltage drop of the switching tube Q1 is lower at this time, and on the premise that the current remains unchanged, compared with the circuit structure shown in fig. 1, the power consumed by the switching tube Q1 is lower, so that the efficiency can be improved while the cost is reduced.
In one embodiment, the discharge unit 40 includes a first inductor L1. A first terminal of the first inductor L1 is connected to the second terminal of the secondary side of the transformer T1 and the second terminal of the freewheel unit 30, and a second terminal of the first inductor L1 is connected to the second terminal of the welding unit 50.
Specifically, when the switching tube Q1 is turned off, the first inductor L1 can output a large current due to the freewheeling action of the first inductor L1, and the current is reduced by charging the first capacitor C1 to protect the welding unit 50. At the same time, the current also contributes to reducing the risk of arc interruption by charging the freewheeling unit 30 so that the freewheeling unit 30 can provide freewheeling for the welding unit 50.
In one embodiment, the freewheeling unit 30 includes a second inductor L2 and a second diode D2. A first terminal of the second inductor L2 is connected to an anode of the second diode D2, a second terminal of the second inductor L2 is connected to a first terminal of the first inductor L1, and a cathode of the second diode D2 is connected to a third terminal of the energy storage unit 10 (i.e., an anode of the first diode D1).
In particular, when the first inductor L1 is discharged, the second inductor L2 is charged, i.e. storage of the second portion of electrical energy output by the first inductor L1 is achieved, so that a follow current can be provided to the welding unit 50 to reduce the risk of arc interruption.
Referring to fig. 5, fig. 5 is a schematic diagram of signals of the blocking circuit 100 shown in fig. 4 during operation according to an embodiment of the present disclosure. Wherein, the curve L501 is a curve of the output current of the blocking circuit 100; a curve L502 is a current flowing through the freewheel unit 30 when blocked; the curve L503 is a curve of the control signal of the switching tube Q1.
As shown in fig. 5, at time T501, the necking process starts, i.e., the current interruption starts, at which time the freewheel unit 30 starts to have the freewheeling current pass through, and the current reaches the maximum value at time T502. Due to the current, the probability of arc breaking in the necking stage can be greatly reduced, and the stable operation of the welding process is favorably maintained.
In one embodiment, the inductance of the first inductor L1 is less than the inductance of the second inductor L2.
In this embodiment, since the inductance of the second inductor L2 is greater than the inductance of the first inductor L1, only a second portion of the current output by the first inductor L1 flows through the second inductor L2 during the turn-off process of the switching transistor Q1. And the second partial current enables the second inductor L2 to provide follow current, namely, the second inductor L2 has strong capability of inhibiting arc breaking, so that the phenomenon of arc breaking in a necking time period is basically avoided in an actual welding process.
In one embodiment, the inductance of the second inductor L2 is greater than or equal to 5 times the inductance of the first inductor L1.
In an embodiment, the welding unit 50 includes a welding arc PWL1, wherein a first terminal of the welding arc PWL1 is connected to the second terminal of the switching unit 20 (i.e., the second terminal of the switching tube Q1) and the second terminal of the energy storage unit 10 (i.e., the cathode of the first diode D1), and a second terminal of the welding arc PWL1 is connected to the second terminal of the discharge unit 40 (i.e., the second terminal of the first inductor L1).
In one embodiment, the blocking circuit 100 further includes a third diode D3 and a fourth diode D4. An anode of the third diode D3 is connected to the first end of the secondary side of the transformer T1, a cathode of the third diode D3 is connected to a cathode of the fourth diode D4, the first end of the energy storage unit 10 (i.e., the first end of the first capacitor C1) and the first end of the switching unit 20 (i.e., the third end of the switching tube Q1), and an anode of the fourth diode D4 is connected to the third end of the secondary side of the transformer T1.
Specifically, the third diode D3 and the fourth diode D4 are used for rectifying the voltage output by the secondary side of the transformer T1.
In an embodiment, the blocking circuit 100 further includes a fifth diode D5, wherein an anode of the fifth diode D5 is connected to the second terminal of the switch Q1 and the cathode of the first diode D1, and a cathode of the fifth diode D5 is connected to the third terminal of the switch Q1.
The fifth diode D5 is a body diode of the switching tube Q1.
For a better understanding of the present application, the principle of the circuit configuration shown in fig. 4 is described below.
When the control unit comes to the moment of necking of the molten drop in the welding process, the switching tube Q1 is controlled to be turned off. At this time, the first inductor L1 discharges due to the freewheeling action of the first inductor L1.
In the first aspect, a first part of the electric energy discharged from the first inductor L1 charges the first capacitor C1 through a loop of the first inductor L1, the third diode D3, the first capacitor C1, the first diode D1 and the welding arc PWL 1. Most of the energy in the first inductor L1 is stored in the first capacitor C1, so that the welding current can be rapidly reduced to a small value when necking, thereby protecting the welding arc PWL 1.
Meanwhile, because the equivalent inductance of the capacitor is smaller, instantaneous peak voltage cannot be generated, the risk that the switching tube Q1 is broken down by voltage can be reduced, and compared with a high-power cement resistor R101 adopted in a related technology shown in figure 1, the high-power cement resistor R101 can effectively protect the switching tube Q1, namely, the service life of the switching tube Q1 can be longer.
And, the process of draining the first capacitor C1 can be realized by turning on the switching tube Q1. The bleed path of the energy stored when the first capacitor C1 necks down is: the welding device comprises a first capacitor C1, a switching tube Q1, a welding arc PWL1, a first inductor L1, a second inductor L2 and a second diode D2. The stored energy is again re-used by welding arc PWL1 to achieve a secondary use of energy, which can reduce energy losses. In the circuit structure shown in fig. 1, the high-power cement resistor R101 directly consumes the energy output by the inductor L101. It can be seen that the embodiment of the present application provides a blocking circuit 100 with less energy loss and thus higher efficiency, relative to the circuit structure shown in fig. 1 in the related art. Moreover, due to the improvement of the efficiency, the blocking circuit 100 provided by the embodiment of the present application can be suitable for working at a higher short circuit transition frequency, that is, the practicability is strong.
In a second aspect, a second portion of the power discharged from the first inductor L1 is used to charge the second inductor L2 through the loop of the first inductor L1, the second inductor L2, the second diode D2, the first diode D1, and the welding arc PWL 1. The energy on the first inductor L1 is stored by the second inductor L2, so that the second inductor L2 has a follow current capability, the probability of arc breaking in a necking time period is reduced, and stable operation of the welding machine is maintained.
In addition, referring to fig. 6, fig. 6 is a schematic diagram of an output voltage and an output current of the blocking circuit 100 shown in fig. 4 in an actual welding process according to an embodiment of the present application. Wherein, the curve L601 is the output voltage; curve L602 is the output current.
As shown in fig. 6, during the actual welding process, the operation of the whole system is stable and the arc breaking phenomenon does not occur. It can be seen that, since the second inductor L2 has a strong capability of suppressing arc breaking, it is not necessary to increase the no-load voltage of the whole system, and it is also not necessary to increase the inductance of the first inductor L1. Therefore, the efficiency can be improved, and the cost of the welding machine can be reduced to a greater extent.
The embodiment of the application also provides a welding machine, which comprises a transformer and the power supply blocking circuit 100 in any embodiment. Wherein the blocking circuit 100 is used for connecting with the secondary side of the transformer.
Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit the same; within the context of the present application, where technical features in the above embodiments or in different embodiments can also be combined, the steps can be implemented in any order and there are many other variations of the different aspects of the present application as described above, which are not provided in detail for the sake of brevity; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present application.
Claims (10)
1. A blocking circuit for connection to a secondary side of a transformer, the blocking circuit comprising:
the device comprises an energy storage unit, a switch unit, a follow current unit, a discharge unit and a welding unit;
the first end of the energy storage unit is connected with the first end of the secondary side and the first end of the switch unit, the second end of the energy storage unit is connected with the second end of the switch unit and the first end of the welding unit, the third end of the energy storage unit is connected with the first end of the follow current unit, the second end of the follow current unit is connected with the first end of the discharge unit and the second end of the secondary side, and the second end of the discharge unit is connected with the second end of the welding unit;
the energy storage unit is used for storing the first part of electric energy output by the discharge unit when the switch unit is turned off so as to reduce the current flowing through the welding unit;
the follow current unit is used for storing the second part of electric energy output by the discharge unit when the switch unit is turned off and providing follow current for the welding unit based on the second part of electric energy.
2. The blocking circuit of claim 1, wherein the energy storage unit comprises a first capacitor and a first diode;
the first end of the first capacitor is connected with the first end of the secondary side and the first end of the switch unit, the second end of the first capacitor is connected with the anode of the first diode and the first end of the follow current unit, and the cathode of the first diode is connected with the second end of the switch unit and the first end of the welding unit.
3. The blocking circuit of claim 2, further comprising a control unit, the switching unit comprising a switching tube;
the first end of the switch tube is connected with the control unit, the third end of the switch tube is connected with the first end of the first capacitor, and the second end of the switch tube is connected with the cathode of the first diode;
the control unit is used for controlling the on or off of the switch tube.
4. The blocking circuit according to claim 3, wherein the control unit is specifically configured to:
acquiring the voltage at two ends of the first capacitor;
and when the voltage at the two ends of the first capacitor is greater than a first voltage threshold value, controlling the switch tube to be conducted.
5. The blocking circuit of claim 1, wherein the discharge unit comprises a first inductor;
the first end of the first inductor is connected with the second end of the secondary side and the second end of the follow current unit, and the second end of the first inductor is connected with the second end of the welding unit.
6. The blocking circuit of claim 5, wherein the freewheeling unit comprises a second inductor and a second diode;
the first end of the second inductor is connected with the anode of the second diode, the second end of the second inductor is connected with the first end of the first inductor, and the cathode of the second diode is connected with the third end of the energy storage unit.
7. The blocking circuit of claim 6,
an inductance value of the first inductor is less than an inductance value of the second inductor.
8. The blocking circuit of claim 1, wherein the welding unit comprises a welding arc;
the first end of the welding arc is connected with the second end of the switch unit and the second end of the energy storage unit, and the second end of the welding arc is connected with the second end of the discharge unit.
9. The blocking circuit of claim 1, further comprising a third diode and a fourth diode;
the anode of the third diode is connected with the first end of the secondary side, the cathode of the third diode is connected with the cathode of the fourth diode, the first end of the energy storage unit and the first end of the switch unit, and the anode of the fourth diode is connected with the third end of the secondary side;
the third diode and the fourth diode are used for rectifying the voltage output by the secondary side.
10. A welding machine comprising a transformer and a blocking circuit as claimed in any one of claims 1 to 9;
the blocking circuit is connected with the secondary side of the transformer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111485971.6A CN114289828A (en) | 2021-12-07 | 2021-12-07 | Blocking circuit and welding machine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111485971.6A CN114289828A (en) | 2021-12-07 | 2021-12-07 | Blocking circuit and welding machine |
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| Publication Number | Publication Date |
|---|---|
| CN114289828A true CN114289828A (en) | 2022-04-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111485971.6A Pending CN114289828A (en) | 2021-12-07 | 2021-12-07 | Blocking circuit and welding machine |
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| Country | Link |
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| CN (1) | CN114289828A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3711058A (en) * | 1970-01-14 | 1973-01-16 | Elektriska Svetsnings Ab | Apparatus for inductor current control in electric arc welding |
| CN111001901A (en) * | 2020-03-09 | 2020-04-14 | 杭州凯尔达电焊机有限公司 | Short-circuit type AC welding control circuit and welding power supply |
-
2021
- 2021-12-07 CN CN202111485971.6A patent/CN114289828A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3711058A (en) * | 1970-01-14 | 1973-01-16 | Elektriska Svetsnings Ab | Apparatus for inductor current control in electric arc welding |
| CN111001901A (en) * | 2020-03-09 | 2020-04-14 | 杭州凯尔达电焊机有限公司 | Short-circuit type AC welding control circuit and welding power supply |
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