Parallel structure of power supply load capacitance

Abstract

The application discloses a parallel structure of power load capacitance, and solves the problem of fixed load capacitance mode in the prior art, which is inconvenient to disassemble and assemble. The application comprises a capacitance module, wherein the capacitance module is provided with an input end and an output end; the capacitance module comprises at least two groups of series-connected busbars, the busbars are provided with a plurality of evenly-distributed capacitance supports, and the capacitance supports are provided with a plurality of evenly-distributed and parallel-connected capacitors. The application has the advantages of simple and reliable structure, convenience in disassembly and assembly, small leakage inductance, parallel connection of multiple capacitors through the parallel structure of power resonance capacitance power capacitors, balanced alternating current and voltage among the capacitors, and reduction of induced inductance caused by the parallel capacitors.

Description

Technical Field

[0001] This invention relates to the field of power supply technology, and in particular to a power supply load capacitor. Background Technology

[0002] Induction heating utilizes the principle of electromagnetic induction to generate eddy currents inside the metal workpiece being heated, using these currents to achieve the purpose of heating the workpiece. The resonant circuit of an induction heating power supply requires high-power capacitors. Different operating environments have different requirements for the capacitance and value of these capacitors. Currently, the single-unit capacitance of power capacitors provided by capacitor manufacturers generally does not meet the power supply requirements, necessitating the use of multiple capacitors in parallel to achieve the required power capacity. The capacitors used in the resonant circuit are also called load capacitors because they are within the power supply's load. Existing parallel capacitor connections are mostly fixed structures, such as direct welding via copper busbars or rigid busbars. Once the capacitor specifications and quantity are determined, they are difficult to adjust. When changes in the induction heating process (such as switching workpiece material, size, or heating frequency) cause changes in the required load capacitor parameters, the original capacitor bank cannot be quickly adapted, requiring complete replacement or redesign, resulting in poor equipment versatility and high upgrade costs. The following problems also exist:

[0003] Disassembly and maintenance are difficult. Fixed connections require specialized tools (such as hydraulic pliers and torque wrenches), and the capacitors are densely packed, requiring the entire capacitor bank to be disassembled when removing or installing a single capacitor, which is time-consuming and labor-intensive. Especially in continuous industrial production scenarios, capacitor failures (such as capacitance decay or breakdown) can lead to prolonged production line downtime, and maintenance efficiency directly impacts production efficiency.

[0004] Poor current sharing performance and low reliability are issues. In hard-connection configurations, the impedance of each capacitor branch varies significantly due to factors such as bus length and contact resistance. Under high-frequency, high-current conditions, uneven current distribution can lead to overload and overheating of some capacitors, accelerating electrolyte drying or film aging, and triggering a chain reaction of failures. Furthermore, mechanical vibration (such as in mobile induction heating equipment) can loosen bolts, increase contact resistance, further exacerbate current imbalance, and even cause arcing, posing safety hazards.

[0005] Redundant heat dissipation designs and low space utilization: To alleviate heat generation caused by poor current sharing, existing solutions often increase capacitor spacing or add forced air cooling channels, resulting in bulky capacitor banks. For example, the load capacitor bank of a certain brand's 50kW induction heating power supply occupies more than 40% of the chassis space, limiting the miniaturization of the equipment, and is particularly unfavorable for the development of portable or integrated heating equipment.

[0006] Lacking the ability to dynamically adjust capacitance, in applications requiring real-time adjustment of resonant parameters (such as variable frequency induction heating and multi-segment temperature curve control), the fixed parallel structure cannot achieve stepless or graded adjustment of capacitance. It can only achieve coarse adjustment by switching the entire group of capacitors, resulting in a slow response speed (usually on the order of seconds). This makes it difficult to meet the microsecond-level parameter adjustment requirements of high-precision heating processes (such as semiconductor zone melting and precision quenching).

[0007] With "rigid connection" as its core, it sacrifices flexibility, maintainability, and reliability, and can no longer adapt to the trend of induction heating equipment developing towards higher frequency, intelligence, and modularity. Especially in medium and high power scenarios (such as above 50kW), the defects of the capacitor parallel structure have become a key bottleneck restricting the performance improvement of induction heating power supplies.

[0008] A prior art patent, such as Chinese Patent No. CN 212365741U, discloses a water-cooled DC filter capacitor, which includes a casing. Inside the casing, several parallel capacitor elements form a first capacitor module and a second capacitor module. A water-cooling coil is located under the outer wall of each capacitor element. Each capacitor element has a first input terminal and a second input terminal. The first input terminal of each capacitor element is connected to a lower main busbar, and the second input terminal is connected to a lower busbar. The lower main busbar extends and is connected to a lower main line terminal, which in turn is connected to a lower auxiliary line terminal extending out of the casing. At the end of the casing away from the lower auxiliary line terminal, there are upper auxiliary line terminals and upper main line terminals. The upper auxiliary line terminal is electrically connected to the lower main busbar, and the upper main line terminal is electrically connected to the lower busbar. The lower main line terminal, lower auxiliary line terminal, and lower main busbar are electrically connected through a main layer plate, and the lower main line terminal and lower busbar are electrically connected through a secondary layer plate. Although this patent reduces capacitor heat generation, it still suffers from inconvenient maintenance and a fixed number of capacitors that are difficult to replace. Summary of the Invention

[0009] To address the shortcomings in the aforementioned background technology, a parallel structure for power supply load capacitors is proposed, which solves the problem that the load capacitor mode is fixed in the prior art, making it inconvenient to disassemble and assemble.

[0010] The technical solution of the present invention is implemented as follows: a parallel structure of power load capacitors, including a capacitor module, the capacitor module having an input terminal and an output terminal; the capacitor module includes at least two sets of busbars connected in series, the busbars having a plurality of uniformly distributed capacitor supports, and the capacitor supports having a plurality of uniformly distributed and parallel capacitors.

[0011] Furthermore, the busbar includes busbar one and busbar two, with an insulating plate between busbar one and busbar two. The output terminal of the capacitor module is located on busbar one and the output terminal is located on busbar two.

[0012] Furthermore, the busbar is provided with a water-passing copper pipe, and the water-passing copper pipe is provided with a water inlet and a water outlet that cooperate with the water-passing copper pipe of the adjacent capacitor module.

[0013] More preferably, the busbar has M rows and N columns of first fixed ends that cooperate with the corresponding capacitor brackets, wherein M is greater than or equal to 2, N is greater than 2, the first fixed ends that are adjacent vertically are staggered, and a first square hole is provided between the first fixed ends that are adjacent horizontally.

[0014] More preferably, the second busbar is provided with a second fixing end corresponding to the first square hole, and the second fixing end cooperates with the first fixing end to fix the capacitor.

[0015] More preferably, the end faces of the first fixed end passing through the insulating plate and the first square hole and the second fixed end are located on the same plane.

[0016] Furthermore, the capacitor support is provided with a second water-conducting copper pipe, which has a U-shaped structure, and the inlet and outlet of the second water-conducting copper pipe are located on the same plane.

[0017] Furthermore, the capacitor module is provided with a support assembly. The support assembly includes a first support bakelite strip and a second support bakelite strip, with the first support bakelite strip located at the lower part of the capacitor module and the second support bakelite strip located at the upper part of the capacitor module.

[0018] More preferably, a third supporting bakelite strip is provided above the second supporting bakelite strip.

[0019] The beneficial effects of the present invention are as follows: The present invention has a simple and reliable structure, is easy to disassemble and expand, has low leakage inductance, and realizes the parallel connection of multiple capacitors through the parallel structure of power resonant capacitor and power capacitor, and the AC current and voltage between capacitors are balanced, reducing the induced inductance caused by parallel capacitors. Attached Figure Description

[0020] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is the front view of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the present invention. Figure 1 ;

[0023] Figure 3 This is a schematic diagram of the structure of the present invention. Figure 1 ;

[0024] Figure 4 This is a schematic diagram of the structure of the first busbar of the present invention;

[0025] Figure 5 This is a schematic diagram of the structure of the second motherboard of the present invention.

[0026] In the diagram: 1. Supporting bakelite strip one, 2. Water pipe one, 3. Water inlet one, 4. Water pipe two, 5. Water outlet one, 6. Busbar one, 7. Insulating plate, 8. First square hole, 9. Supporting bakelite strip two, 10. Supporting bakelite strip three, 11. Busbar two, 12. Water outlet two, 13. Load capacitor, 14. Water inlet two, 15. Capacitor bracket one, 16. Capacitor bracket two, 17. Capacitor bracket three, 18. Capacitor bracket four, 19. Capacitor bracket five, 20. Capacitor bracket six, 21. Capacitor bracket seven, 22. Capacitor bracket eight, 23. Capacitor bracket nine, 24. Capacitor bracket ten, 25. Capacitor bracket eleven, 26. Capacitor bracket twelve, 27. Capacitor bracket thirteen, 28. Capacitor bracket fourteen, 29. Capacitor bracket fifteen, 30. Capacitor bracket sixteen, 31. Capacitor bracket seventeen, 32. Capacitor bracket eighteen, 33. Capacitor bracket nineteen, 3 4. Capacitor bracket 20, 35. Capacitor bracket 21, 36. Capacitor bracket 22, 37. Capacitor bracket 23, 38. Capacitor bracket 24, 39. Input terminal 1, 40. Input terminal 2, 41. Output terminal 1, 42. Output terminal 2, 43. Fixed terminal 1, 44. Fixed terminal 2, 45. Fixed terminal 3, 46. Fixed terminal 4, 47. Fixed terminal 5, 48. Fixed terminal 6, 49. Fixed terminal 7, 50. Fixed End 8, 51. Square Hole 1, 52. Square Hole 2, 53. Square Hole 3, 54. Square Hole 4, 55. Square Hole 5, 58. Square Hole 6, 57. Square Hole 7, 58. Square Hole 8, 59. Fixed End 9, 60. Fixed End 10, 61. Fixed End 11, 62. Fixed End 12, 63. Fixed End 13, 64. Fixed End 14, 65. Fixed End 15, 66. Fixed End 16, 67. First Fixed End, 68. Second Fixed End. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0028] like Figure 1 and Figure 2As shown in Embodiment 1, a parallel structure for a power supply load capacitor includes a load capacitor module with an input terminal and an output terminal. The load capacitor module includes at least two sets of busbars connected in series. Several uniformly distributed capacitor supports are provided on the busbars, and several uniformly distributed and parallel-connected load capacitors 13 are provided on the capacitor supports. The number of busbars can be adjusted as needed. The series busbar structure is simple and reliable, easy to disassemble and expand, and has low leakage inductance. The parallel structure of the power load capacitors (power resonant capacitors 13 and 13) achieves the parallel connection of multiple load capacitors, and the AC current and voltage among the load capacitors 13 are balanced, reducing the induced inductance caused by the parallel load capacitors 13.

[0029] like Figure 4 and Figure 5 As shown in Embodiment 2, a parallel structure of a power supply load capacitor is provided. The busbar includes a first busbar 6 and a second busbar 11 arranged in parallel. An insulating plate 7, made of polytetrafluoroethylene (PTFE), is provided between the first busbar 6 and the second busbar 11 to isolate the first busbar 6 and the second busbar 11 and prevent high-voltage breakdown. The output terminal of the load capacitor module is located on the first busbar 6 and the output terminal is located on the second busbar 11. The insulating plate 7 between the first busbar 6 and the second busbar 11 can also reduce heat transfer between the two busbars, force current sharing, avoid overcurrent failure of individual load capacitors 13, prevent the expansion of busbar short circuit accidents, require no maintenance for a long time, and have low life cycle costs.

[0030] In a preferred embodiment, the busbar 6 is provided with a water-conducting copper pipe 2, which has an inlet nozzle 14 and an outlet nozzle 12 that cooperate with the water-conducting copper pipe 2 of the adjacent load capacitor module. The water-conducting copper pipe 2 can be laid in an S-shape on the busbar to improve the cooling effect of the busbar. The busbar 6 has M rows and N columns of first fixed ends 67 that cooperate with the corresponding capacitor brackets, where M is greater than or equal to 2, N is greater than 2, and the vertically adjacent first fixed ends 67 are staggered, and the horizontally adjacent first fixed ends 67 are provided with a first square hole 8. The first fixed ends 67 and the first square holes 8 are spaced apart, and the positions of the first fixed ends 67 in the upper row and the first square holes 8 in the lower row correspond. The load capacitor 13 is installed between the first fixed ends 67 and the first square holes 8.

[0031] In another preferred embodiment, the busbar 6 is provided with a water-conducting copper pipe 2. The water-conducting copper pipe 2 has a second inlet 14 and a second outlet 12 that cooperate with the water-conducting copper pipes 2 of adjacent load capacitor modules. The water-conducting copper pipe 2 is a U-shaped pipe used for cooling the busbar. Preferably, the second outlet 12 and the second inlet 14 are located on the same side for easy expansion. The busbar 6 has four rows and three columns of first fixing ends 67 that cooperate with corresponding capacitor supports. The vertically adjacent first fixing ends 67 are staggered, and a first square hole 8 is provided between the horizontally adjacent first fixing ends 67. The first fixing ends 67 and the first square holes 8 are evenly distributed on the busbar 6, facilitating the installation, removal, ventilation, and heat dissipation of the load capacitors 13.

[0032] In this embodiment, the second busbar 11 is provided with a second fixed end 68 corresponding to the first square hole 8. The second fixed end 68 cooperates with the first fixed end 67 to fix the load capacitor 13. The end faces of the first fixed end 67 passing through the first square hole 8 and the second fixed end 68 are located on the same plane. The fixed end on the second busbar 11 extends out of the first square hole 8 through the groove on the insulating plate 7, and the length and width of the groove are both smaller than the first square hole 8, to prevent the busbar short circuit from escalating and to avoid the second fixed end 68 from contacting the first busbar 6, thereby improving the safety of the device.

[0033] All other structures are the same as in Example 1.

[0034] like Figure 2 and Figure 3 As shown in Embodiment 3, a parallel structure of a power supply load capacitor is provided. The capacitor support is equipped with a second copper water pipe 4, which has a U-shaped structure. The inlet and outlet of the second copper water pipe 4 are located on the same plane. The second copper water pipe 4 on the capacitor support is used to cool the capacitor support and the load capacitor 13 mounted on it. The cooling effect is good. Each capacitor support is equipped with a cooling module, which can also avoid the self-heating problem caused by plugging and unplugging the load capacitor 13, thus preventing the load capacitor 13 from failing.

[0035] All other structures are the same as in Example 2.

[0036] like Figure 3 and Figure 4 As shown in Embodiment 4, a parallel structure of a power supply load capacitor is provided, wherein the load capacitor module is provided with a support component. The support component is used to fix the parallel load capacitor modules.

[0037] In a preferred embodiment, the support assembly includes a first support bakelite strip 1 and a second support bakelite strip 9. The first support bakelite strip 1 is located at the lower part of the load capacitor module, and the second support bakelite strip 9 is located at the lower part of the load capacitor module. A third support bakelite strip 10 is provided above the second support bakelite strip 9. Three support bakelite strips 1 and 9 are provided, corresponding vertically. These three bakelite strips are used to install two series-connected load capacitor modules, resulting in a simple installation method and good structural stability.

[0038] As another preferred embodiment, the supporting bakelite strip 1 and supporting bakelite strip 9 can be selected as a rectangular frame structure. The capacitor bracket is installed inside the rectangular frame, which can further fix the load capacitor module and ensure the stability of the load capacitor module.

[0039] All other structures are the same as in Example 3.

[0040] like Figures 1-5 As shown in Embodiment 4, a parallel structure for a power load capacitor mainly consists of two sets of capacitor modules connected in series. The two sets of capacitor modules are mounted on three supporting bakelite strips 1. Three supporting bakelite strips 2 9 are mounted on the top of the two sets of capacitor modules to fix the capacitor modules. A supporting bakelite strip 3 10 is mounted on the middle supporting bakelite strip 2 9 to install the parallel structure of the power load capacitor.

[0041] Capacitor Module: The capacitor module consists of twelve load capacitors 13 connected in parallel via busbar 6 and busbar 11.

[0042] A U-shaped copper water pipe 2 is installed in the middle of the busbar 6. A water inlet 14 and a water outlet 12 are respectively installed at both ends of the copper water pipe 2. From left to right and top to bottom, the busbar 6 is arranged with the following terminals in sequence: fixed end 43, square hole 51, fixed end 2 44, square hole 2 52, square hole 3 53, fixed end 3 45, square hole 4 54, fixed end 46, fixed end 5 47, square hole 55, fixed end 6 48, square hole 6 56, square hole 7 57, fixed end 7 49, square hole 8 58, and fixed end 8 50. An input end 39 is installed at the right end of the busbar 6.

[0043] The busbar 2 11 is provided with fixed end 9 59, fixed end 10 60, fixed end 11 61, fixed end 12 62, fixed end 13 63, fixed end 14 64, fixed end 15 65, and fixed end 16 66 in sequence from left to right and from top to bottom.

[0044] Busbar 1 (6) and Busbar 2 (11) are stacked, and a polytetrafluoroethylene (PTFE) insulating plate (7) is placed between them. Corresponding to square holes 1 (51), 2 (52), 3 (53), 4 (54), 5 (55), 6 (56), 7 (57), and 8 (58), corresponding square holes are provided on the PTFE insulating plate (7). Fixed ends 9 (59), 10 (60), 11 (61), 12 (62), 13 (63), 14 (64), 15 (65), and 16 (66) pass through the square holes 1 (51), 2 (52), 3 (53), 4 (54), 5 (55), 6 (56), 7 (57), 8 (58), and the corresponding square holes on the PTFE insulating plate (7). The fixing surfaces of all fixed ends are on the same plane.

[0045] Capacitor bracket 1 15, Capacitor bracket 2 16, Capacitor bracket 3 17, Capacitor bracket 4 18, Capacitor bracket 5 19, Capacitor bracket 6 20, Capacitor bracket 7 21, Capacitor bracket 8 22, Capacitor bracket 9 23, Capacitor bracket 10 24, Capacitor bracket 11 25, Capacitor bracket 12 26, Capacitor bracket 13 27, Capacitor bracket 14 28, Capacitor bracket 15 29, Capacitor bracket 16 30, Capacitor bracket 17 31, Capacitor bracket 18 32, Capacitor bracket 19 33, Capacitor bracket 2 Capacitor supports 34, 35, 36, 37, 38 are respectively installed on fixed ends 43, 59, 44, 60, 61, 45, 62, 46, 47, 63, 48, 64, 65, 49, 66, and 50. Two capacitor supports are installed on each of the fixed ends 59, 44, 45, 42, 63, 63, 64, 65, 49, and 66, while one capacitor support is installed on each of the remaining fixed ends. A water-passing copper pipe 4 is installed on each capacitor support, with an inlet 3 and an outlet 5 at each end of the water-passing copper pipe 4. An output terminal 41 is provided at the left end of the busbar 2 11.

[0046] A load capacitor 13 is provided between the capacitors of each adjacent fixed terminal.

[0047] Input terminal 2 40 and output terminal 2 42 are connected to another set of capacitor modules. In use, output terminal 1 41 and output terminal 2 42 are connected in series with a downstream load, thus realizing the series connection of the two sets of capacitor modules.

[0048] Connect all the copper water pipes with flexible hoses and introduce cooling water. Connect input terminal 39 and input terminal 40 to the upstream power supply, and connect output terminal 41 and output terminal 42 to the downstream load.

[0049] 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 within the protection scope of the present invention.

Claims

1. A parallel structure for a power supply load capacitor, characterized in that, It includes a load capacitor module, which has an input terminal and an output terminal; the load capacitor module includes at least two sets of busbars connected in series, the busbars are provided with a number of uniformly distributed capacitor supports, and the capacitor supports are provided with a number of uniformly distributed and parallel load capacitors (13).

2. The parallel structure of the power supply load capacitor according to claim 1, characterized in that, The busbar includes busbar one (6) and busbar two (11), with an insulating plate (7) between busbar one (6) and busbar two (11). The output terminal of the load capacitor module is located on busbar one (6) and the output terminal is located on busbar two (11).

3. The parallel structure of the power supply load capacitor according to claim 2, characterized in that, The busbar 1 (6) is provided with a water-passing copper pipe (2), and the water-passing copper pipe (2) is provided with a water inlet 2 (14) and a water outlet 2 (12) that cooperate with the water-passing copper pipe (2) of the adjacent load capacitor module.

4. The parallel structure of the power supply load capacitor according to claim 3, characterized in that, The busbar (6) is provided with M rows and N columns of first fixed ends (67) that cooperate with the corresponding capacitor brackets. M is greater than or equal to 2, N is greater than 2, the first fixed ends (67) that are adjacent vertically are staggered, and the first fixed ends (67) that are adjacent horizontally are provided with a first square hole (8).

5. The parallel structure of the power supply load capacitor according to claim 4, characterized in that, The busbar 2 (11) is provided with a second fixed end (68) corresponding to the first square hole (8), and the second fixed end (68) cooperates with the first fixed end (67) to fix the load capacitor (13).

6. The parallel structure of the power supply load capacitor according to claim 5, characterized in that, The first fixed end (67) passes through the insulating plate (7) and the first square hole (8), and the end face of the second fixed end (68) is on the same plane.

7. The parallel structure of the power supply load capacitor according to claim 6, characterized in that, The capacitor support is provided with a water-conducting copper pipe 2 (4), which has a U-shaped structure. The water inlet and outlet of the water-conducting copper pipe 2 (4) are located on the same plane.

8. The parallel structure of the power supply load capacitor according to any one of claims 1 to 7, characterized in that, The load capacitor module is equipped with a support component.

9. The parallel structure of the power supply load capacitor according to claim 8, characterized in that, The support assembly includes a first support bakelite strip (1) and a second support bakelite strip (9). The first support bakelite strip (1) is located at the lower part of the load capacitor module, and the second support bakelite strip (9) is located at the upper part of the load capacitor module.

10. The parallel structure of the power supply load capacitor according to claim 9, characterized in that, Above the second (9) supporting bakelite strip is a third (10) supporting bakelite strip.

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