IGBT medium-frequency power supply device for large-tonnage induction furnace

Abstract

The utility model belongs to the technical field of medium-frequency induction furnaces, and discloses an IGBT (Insulated Gate Bipolar Translator) medium-frequency power supply device for a large-tonnage induction furnace, which comprises a cabinet body, a control part, a rectification part, an inverter bridge and a square capacitor device are arranged in the cabinet body, the square capacitor device comprises a plurality of capacitor banks which are connected in series, and the capacitor banks are connected through copper bar groups. At least one capacitor bank is arranged above and below the copper bar group, the control part is arranged above the copper bar group, and the rectification part is arranged on one side of the copper bar group and the control part; according to the utility model, the square capacitors arranged up and down are adopted, so that the effects of small size, low energy consumption and compact structure are achieved, and the device can be suitable for power supply of the large-tonnage medium-frequency induction furnace.

Description

Technical Field

[0001] The utility model relates to the technical field of medium frequency induction furnaces, in particular to an IGBT medium frequency power supply device for a large-tonnage induction furnace. Background Art

[0002] IGBT medium frequency induction furnace is an induction heating device that uses IGBT (insulated gate bipolar transistor) technology. Through the principle of electromagnetic induction, the metal material generates eddy currents in the medium frequency alternating magnetic field, thereby achieving rapid heating.

[0003] The main components of IGBT medium frequency induction furnace include medium frequency power supply, induction coil, furnace body, control system, etc. The medium frequency power supply device adopts power switch components such as thyristor and IGBT, and uses IGBT inverter technology to rectify three-phase industrial frequency AC into DC, which becomes a constant DC current after being smoothed by the reactor, and then inverts the DC into single-phase medium frequency AC of a certain frequency through the inverter bridge.

[0004] In the Chinese utility model patent with patent application number 202220274062.1, an IGBT dual-unit transistor medium-frequency power supply device is proposed. The problems with this patent are: on the one hand, the cylindrical capacitors used in this patent are suitable for occasions with relatively small loads; on the other hand, as the load increases, the number of capacitors also needs to increase. At the same time, for the horizontally arranged capacitor layout structure, the medium-frequency power supply of a large-tonnage medium-frequency induction furnace will be very large, and it will be difficult to have enough space for installation; the third aspect is that the increase in the number of capacitors means that the number of copper busbars and cooling fans will increase, which will lead to relatively high energy consumption of the power supply cabinet. Utility Model Content

[0005] The main technical problem to be solved by the utility model is to provide an IGBT medium frequency power supply device for a large-tonnage induction furnace, which adopts square capacitors with an upper and lower layout to achieve the effects of small size, low energy consumption and compact structure, and can be adapted to the power supply of a large-tonnage medium frequency induction furnace.

[0006] In order to solve the above technical problems, the utility model provides the following technical solutions:

[0007] An IGBT medium frequency power supply device for a large-tonnage induction furnace comprises a cabinet, a control part is arranged at the upper end of the cabinet, a rectifier part is arranged below the control part, a square capacitor device arranged up and down is arranged on one side of the control part and the rectifier part, and the rectifier part is connected to the square capacitor device through an inverter bridge;

[0008] The square capacitor device comprises a plurality of capacitor groups arranged in series, the capacitor groups are connected by copper bar groups, and at least one capacitor group is arranged above and below the copper bar group;

[0009] The control part is arranged above the copper bar group, and the rectifying part is arranged on one side of the copper bar group and the control part.

[0010] The following is a further optimization of the above technical solution by the utility model:

[0011] Each of the capacitor groups comprises a first filter capacitor, a second filter capacitor and a resonant capacitor which are arranged in sequence. A driving module is installed on the first filter capacitor, and each driving module is connected to an adjacent second filter capacitor.

[0012] Further optimization: the control part includes a power controller and a control box arranged on the left and right, the rectifier part is arranged below the power controller, the copper busbar group is arranged horizontally below the control box, and the capacitor group located above the copper busbar group is arranged on the right side of the control box.

[0013] Further optimization: the rectifier part includes a reactor and an inverter arranged in series, and the reactor and the inverter are connected to the square capacitor device through a copper bar group.

[0014] Further optimization: the copper bar group includes a first copper bar, a second copper bar, a third copper bar and a fourth copper bar which are arranged in sequence from front to back, the resonant capacitor is connected in series with the first filter capacitor through the first copper bar and the second copper bar, all the resonant capacitors are connected in series through the third copper bar, and all the second filter capacitors are connected in series through the fourth copper bar.

[0015] Further optimization: the reactor is connected to an inverter bridge, the inverter bridge is connected to the resonant capacitor and the first filter capacitor through a first copper bus, and the inverter is connected to the resonant capacitor and the first filter capacitor through a second copper bus.

[0016] The utility model adopts the above technical solution and has the following beneficial effects: the utility model adopts the above technical solution, the layout structure of the capacitor group is compact and reasonable, and on the basis of the medium-frequency induction furnace of the same tonnage, the volume of the cabinet in the utility model can be half the size of the traditional power cabinet, achieving the purpose of reducing the volume and saving space.

[0017] Compared with the traditional IGBT medium frequency power supply device, the square capacitor in the utility model has a small heat dissipation requirement, so the heat dissipation fan located at the rear side of the capacitor is cancelled, thereby reducing the energy consumption of the power supply and achieving the purpose of energy saving.

[0018] The compact arrangement of capacitors up and down also reduces the use of copper bars, which not only reduces the manufacturing cost of the power supply, but also reduces the energy consumption of the power supply, achieving the effect of cost reduction and energy saving.

[0019] The utility model is further described below in conjunction with the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 It is a schematic diagram of the overall structure in an embodiment of the utility model.

[0022] In the figure: 1-cabinet; 2-control part; 21-power controller; 22-control box; 3-rectifier part; 31-reactor; 32-inverter; 4-square capacitor device; 41-first filter capacitor; 42-second filter capacitor; 43-resonance capacitor; 44-drive module; 5-inverter bridge; 6-copper bar group; 61-first copper bar; 62-second copper bar; 63-third copper bar; 64-fourth copper bar. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0024] like Figure 1 As shown, an IGBT medium frequency power supply device for a large-tonnage induction furnace includes a cabinet 1, a control part 2 is arranged at the upper end of the cabinet 1, a rectifier part 3 is arranged below the control part 2, and a square capacitor device 4 arranged up and down is arranged on one side of the control part 2 and the rectifier part 3, and the rectifier part 3 is connected to the square capacitor device 4 through an inverter bridge 5.

[0025] In this embodiment, the structure and principle of the inverter bridge 5 constitute the prior art, which is well known to those skilled in the art and will not be described in detail here.

[0026] The square capacitor device 4 includes a plurality of capacitor groups arranged in series, and the capacitor groups are connected through a copper bar group 6 . At least one capacitor group is arranged above and below the copper bar group 6 .

[0027] In this embodiment, the internal structure of the square capacitor and the series connection principle and structure between the capacitors are prior art and well known to ordinary technicians in this field, and will not be described in detail here.

[0028] Compared with the structure of the horizontal layout of capacitors in the traditional IGBT medium frequency power supply device, the utility model adopts a structure in which the capacitors are arranged in parallel up and down, which not only realizes the compact and reasonable layout between the capacitor groups, but also effectively improves the utilization rate of the internal space of the cabinet 1, thereby effectively reducing the size of the power supply.

[0029] The volume of the cabinet 1 in the utility model is half the size of the traditional power cabinet, so it can be used in large-tonnage induction furnaces, thereby solving the problem that IGBT medium-frequency power supply devices cannot be used in large-tonnage induction furnaces.

[0030] The control part 2 is arranged above the copper bar group 6 , and the rectifying part 3 is arranged on one side of the copper bar group 6 and the control part 2 .

[0031] Each capacitor group includes a first filter capacitor 41 , a second filter capacitor 42 and a resonant capacitor 43 which are arranged in sequence. A driving module 44 is mounted on the first filter capacitor 41 , and each driving module 44 is connected to an adjacent second filter capacitor 42 .

[0032] In this embodiment, the structure and principle of the driving module 44 constitute the prior art and will not be described in detail here.

[0033] In this embodiment, the driving module 44 is connected to the circuit of the second filter capacitor 42 via a connecting copper busbar.

[0034] In this embodiment, the driving module 44 is disposed on the first filtering capacitor 41 , and the capacitor and the driving module 44 do not need to be disposed separately, thereby realizing a compact arrangement of the driving module 44 and the capacitor group, thereby achieving the effect of saving space.

[0035] Compared with the heat dissipation fan arranged at the rear side of the capacitor in the traditional IGBT medium frequency power supply, the utility model does not need to arrange a heat dissipation fan at the rear side of the capacitor, thereby reducing the energy consumption of the medium frequency power supply device and achieving the purpose of energy saving.

[0036] The control part 2 includes a power controller 21 and a control box 22 arranged on the left and right. The rectifier part 3 is arranged below the power controller 21. The copper busbar group 6 is horizontally arranged below the control box 22. The capacitor group located above the copper busbar group 6 is arranged on the right side of the control box 22.

[0037] In this embodiment, the structure, circuit connection relationship and control principle of the control box 22 constitute the prior art and are well known to ordinary technicians in this field, so they will not be repeated here.

[0038] The rectifying part 3 includes a reactor 31 and an inverter 32 which are connected in series. The reactor 31 and the inverter 32 are connected to the square capacitor device 4 through a copper bar group 6 .

[0039] In this embodiment, the connection relationship between the reactor 31, the inverter 32 and other electrical components in the rectifying part 3 and the rectification principle constitute the prior art, which is well known to ordinary technicians in this field and will not be repeated here.

[0040] The copper bar group 6 includes a first copper bar 61, a second copper bar 62, a third copper bar 63 and a fourth copper bar 64 which are arranged in sequence from front to back. The resonant capacitor 43 is connected in series with the first filter capacitor 41 through the first copper bar 61 and the second copper bar 62, all the resonant capacitors 43 are connected in series through the third copper bar 63, and all the second filter capacitors 42 are connected in series through the fourth copper bar 64.

[0041] In this embodiment, the copper bar group 6 is provided to realize the interconnection of the circuits between the rectifying part 3 and the square capacitor device 4 in the cabinet 1 .

[0042] The series connection of the resonant capacitor 43 and the first filter capacitor 41 is achieved through the first copper bar 61 and the second copper bar 62 , the series connection of all the resonant capacitors 43 is achieved through the third copper bar 63 , and the series connection of all the second filter capacitors 42 is achieved through the fourth copper bar 64 .

[0043] In this embodiment, the number of copper bars used is less than that of a traditional IGBT medium frequency power supply device, which not only reduces the manufacturing cost of the power supply device, but also reduces the energy consumption of the power supply device, thereby achieving the purpose of reducing costs and increasing efficiency.

[0044] The reactor 31 is connected to the inverter bridge 5 , and the inverter bridge 5 is connected to the resonant capacitor 43 and the first filter capacitor 41 through the first copper busbar 61 . The inverter 32 is connected to the resonant capacitor 43 and the first filter capacitor 41 through the second copper busbar 62 .

[0045] The working principle of the utility model is as follows: the working state of the power supply is controlled by the power supply controller 21 and the control box 22. First, the external three-phase industrial frequency AC power is rectified by the inverter 32 to achieve the purpose of converting AC to DC.

[0046] Then the DC power is filtered by the reactor 31 to remove the AC noise in the DC power, thus forming a constant DC power supply.

[0047] Then the constant DC power source is inverted into a single-phase medium-frequency AC power with a certain frequency through an inverter bridge 5 .

[0048] Finally, the intermediate frequency alternating current is separated from the direct current in the intermediate frequency alternating current through the resonant capacitor 43, the first filter capacitor 41 and the second filter capacitor 42, and the alternating current is filtered to remove high-frequency noise and clutter in the alternating current and reduce harmonics.

[0049] Finally, the obtained single-phase medium frequency current output is provided to the induction furnace.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An IGBT medium frequency power supply device for a large-tonnage induction furnace, comprising a cabinet (1), characterized in that: A control part (2) is arranged at the upper end of the cabinet (1), a rectifier part (3) is arranged below the control part (2), and square capacitor devices (4) arranged up and down are arranged on one side of the control part (2) and the rectifier part (3), and the rectifier part (3) is connected to the square capacitor device (4) via an inverter bridge (5); The square capacitor device (4) comprises a plurality of capacitor groups arranged in series, the capacitor groups being connected via a copper bar group (6), and at least one capacitor group is arranged above and below the copper bar group (6); The control part (2) is arranged above the copper bar group (6), and the rectifying part (3) is arranged on one side of the copper bar group (6) and the control part (2).

2. The IGBT medium frequency power supply device for a large tonnage induction furnace according to claim 1 is characterized in that: Each of the capacitor groups comprises a first filter capacitor (41), a second filter capacitor (42) and a resonant capacitor (43) which are arranged in sequence; a drive module (44) is mounted on the first filter capacitor (41); and each drive module (44) is connected to an adjacent second filter capacitor (42).

3. The IGBT medium frequency power supply device for a large tonnage induction furnace according to claim 2 is characterized in that: The control part (2) comprises a power controller (21) and a control box (22) arranged on the left and right, the rectifier part (3) is arranged below the power controller (21), the copper bar group (6) is arranged horizontally below the control box (22), and the capacitor group located above the copper bar group (6) is arranged on the right side of the control box (22).

4. The IGBT medium frequency power supply device for a large tonnage induction furnace according to claim 3 is characterized in that: The rectifying part (3) comprises a reactor (31) and an inverter (32) which are arranged in series, and the reactor (31) and the inverter (32) are connected to the square capacitor device (4) via a copper bar group (6).

5. The IGBT medium frequency power supply device for a large tonnage induction furnace according to claim 4 is characterized in that: The copper bar group (6) comprises a first copper bar (61), a second copper bar (62), a third copper bar (63) and a fourth copper bar (64) which are arranged in sequence from front to back; the resonant capacitor (43) is connected in series with the first filter capacitor (41) via the first copper bar (61) and the second copper bar (62); all the resonant capacitors (43) are connected in series via the third copper bar (63); and all the second filter capacitors (42) are connected in series via the fourth copper bar (64).

6. The IGBT medium frequency power supply device for a large tonnage induction furnace according to claim 5, characterized in that: The reactor (31) is connected to an inverter bridge (5), the inverter bridge (5) is connected to the resonant capacitor (43) and the first filter capacitor (41) via a first copper busbar (61), and the inverter (32) is connected to the resonant capacitor (43) and the first filter capacitor (41) via a second copper busbar (62).

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