Laminated copper bar structure
By using insulating paper for isolation and connection in the stacked copper busbar, the problems of complex manufacturing, high cost and large stray inductance in the prior art are solved, and a stacked copper busbar structure with low cost, low stray inductance and good current sharing effect is realized.
Patent Information
- Application Number
- CN202422745500.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-12
- Publication Date
- 2025-11-11
- Estimated Expiration
- 2034-11-12
AI Technical Summary
Existing stacked copper busbars suffer from problems such as cumbersome and expensive manufacturing processes, high stray inductance, high risk of module damage, and poor current sharing performance.
The DC bus copper busbars P+ and P- are isolated by insulating paper II and insulating paper I. The IGBT module and the electrolytic capacitor are connected by screw fixing holes. The series copper busbars of the electrolytic capacitors are isolated by insulating paper I, achieving good insulation and series-parallel connection.
This reduces production costs, minimizes stray inductance, improves current sharing, and ensures the safety and lifespan of IGBT modules.
Smart Images
Figure CN223540024U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of wiring structures, and more specifically, to a stacked copper busbar structure. Background Technology
[0002] Laminated copper busbars, also known as composite copper busbars, are multi-layered composite structure busbars. Compared to traditional, time-consuming, and difficult-to-install wiring methods, laminated copper busbars provide a modern, easy-to-assemble, clearly structured, and easy-to-design power distribution system. Currently, laminated copper busbars are widely used in inverter units of power electronics such as frequency converters, inverters, and servo drives.
[0003] Currently, there are two main methods for stacked copper busbars: one is a professional stacked copper busbar, which involves stacking positive and negative plates and then isolating them with an insulating layer at the plate contact surface. Its disadvantage is that manufacturing this type of stacked copper busbar requires a professional mold opening and pressing process, which is complicated and expensive. The other method involves fixing the copper busbars separately to the power supply and power take-off sides, with a large gap between the copper busbars. This causes the stray inductance of the busbar to increase, resulting in a rise in the module's peak voltage, which can damage the module or electrolytic capacitors. In addition, the impedance matching of the copper busbars to the power supply side is inconsistent, which leads to a decrease in the current sharing effect of the module and can seriously damage the module. Summary of the Invention
[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a stacked copper busbar structure that is low in cost, easy to manufacture, has low stray inductance, and good current sharing effect.
[0005] To achieve the above objectives, this utility model discloses a stacked copper busbar structure, comprising a DC busbar P+, insulating paper II, an electrolytic capacitor series copper busbar, insulating paper I, a DC busbar P-, and an IGBT (Insulated Gate Bipolar Transistor). Bipolar Transistor (IGBT) module, electrolytic capacitors; The upper end of the DC bus copper bus P+ has screw holes for powering the upper bridge collector pin of the IGBT module; the upper end of the DC bus copper bus P- has screw holes for powering the lower bridge emitter pin of the IGBT module; both DC bus copper bus P+ and DC bus copper bus P- have windows corresponding to the IGBT module; the IGBT module connects to the DC bus copper bus P+ and DC bus copper bus P- through the corresponding screw holes; the DC bus copper bus P+ and DC bus copper bus P- are insulated and bonded together by insulating paper II in the middle; there are multiple electrolytic capacitors, and the pins of each electrolytic capacitor are connected in series and parallel through the corresponding screw holes on the series copper bus of the electrolytic capacitors; both DC bus copper bus P+ and DC bus copper bus P- have screw holes for connecting electrolytic capacitors, which are connected to the positive and negative pins of the electrolytic capacitors respectively; insulating paper I is used for isolation and insulation between the DC bus copper bus P- and the series copper bus of the electrolytic capacitors.
[0006] More specifically:
[0007] DC bus copper bus P+,
[0008] The upper end has screw fixing holes for the IGBT module's bridge collector to draw power from the DC bus copper bus P+. The DC bus copper bus P+ is provided with insulating paper II, which isolates the upper end of the DC bus copper bus P+ from the DC bus P-, and isolates the lower end from the electrolytic capacitor in series with the copper bus. The lower side of the DC bus copper bus P+ is provided with electrolytic capacitor screw holes corresponding to the positive pin of the electrolytic capacitor.
[0009] DC bus copper busbar P-,
[0010] The DC bus copper bus P- has screw fixing holes at its upper end for the IGBT module lower bridge emitter to draw power from the DC bus copper bus P-. The DC bus copper bus P- is connected in series with the upper electrolytic capacitor. The copper bus is separated by insulating paper I, and there is an electrolytic capacitor screw hole in the middle that corresponds to the negative terminal pin of the electrolytic capacitor.
[0011] Electrolytic capacitors connected in series with copper busbars
[0012] The series copper busbar of the electrolytic capacitor is connected to the lead of the electrolytic capacitor through screw holes and insulating paper I, so that the electrolytic capacitor is connected in series and parallel.
[0013] IGBT module,
[0014] The IGBT module draws power from the DC bus copper bus P+ and DC bus copper bus P-;
[0015] The collector pin of the IGBT module is powered by connecting to the upper screw fixing hole of the DC bus copper bus P+, and the emitter pin is powered by connecting to the upper screw fixing hole of the DC bus copper bus P-.
[0016] Insulating paper I,
[0017] Insulating paper I is made of high voltage and high temperature resistant material to isolate the non-series connection part between the DC bus copper bus P- and the series copper bus of the electrolytic capacitor, ensuring the correct series circuit of the electrolytic capacitor;
[0018] Insulating paper II,
[0019] Insulating paper II uses high-voltage and high-temperature resistant materials to isolate the DC bus copper bus P+ and DC bus copper bus P-, achieving insulation between the positive and negative copper busbars;
[0020] The upper left side of the insulating paper II has a rollable structure, and a positioning hole is provided on its right side corresponding to the P+ power supply screw hole 704. The edge of the insulating paper II should be at least 1cm larger than the edge of the DC bus copper bus P+.
[0021] In the stacked copper busbars of this utility model, the DC busbar P+ has a power supply screw hole on the right side corresponding to the power supply copper busbar screw hole, and a power take-off screw hole on the left side suspended for power take-off of other parts; the power take-off screw hole and the power supply screw hole correspond to the positioning holes on the left and right sides of the insulating paper II; the DC busbar P- has a power supply screw hole on the right side corresponding to the power supply copper busbar screw hole, and a power take-off screw hole on the left side suspended for power take-off of other parts, the power take-off screw hole on the left side is below the rollable part on the left side of the insulating paper II, and is separated from the DC busbar P+.
[0022] In the stacked copper busbars of this utility model, the screw holes of the electrolytic capacitor series copper busbar that contact the DC bus copper busbar P- correspond to the screw holes of the electrolytic capacitor series copper busbar that contact the DC bus copper busbar P-, and the non-contacting parts are isolated by insulating paper I. The screw holes of the electrolytic capacitor series copper busbar that contact the DC bus copper busbar P+ correspond to the screw holes of the electrolytic capacitor series copper busbar P- and DC bus copper busbar P+, and the non-contacting parts are isolated by insulating paper II. This enables the electrolytic capacitors connected in series and parallel to the DC bus copper busbar P- and DC bus copper busbar P+.
[0023] In the stacked copper busbar of this utility model, insulating paper I and insulating paper II can achieve good insulation under high temperature conditions, ensuring that the temperature rise of the IGBT module during operation will not affect its insulation.
[0024] Furthermore, the aforementioned DC bus copper bus P+, DC bus copper bus P-, and electrolytic capacitor series copper bus are fixed to the electrolytic capacitor pins via screw holes along with the corresponding insulating paper I and insulating paper II.
[0025] In the stacked copper busbars of this utility model, the DC busbar copper busbar P+ and the DC busbar copper busbar P- are isolated by insulating paper II, and the corresponding screw holes and positioning holes are aligned. In vertical space, the two busbar copper busbars are parallel and do not directly contact each other.
[0026] In the stacked copper busbars of this utility model, the power take-off screw holes of the DC busbar P+ and the DC busbar P- on the left side are staggered and separated by insulating paper. The power take-off screw hole of the DC busbar P- is buried under the rollable part on the left side of the insulating paper II.
[0027] In the stacked copper busbar of this utility model, the right side of the DC busbar P+ has an opening to avoid direct connection with the DC busbar P-.
[0028] Furthermore, the above IGBT modules are arranged in a three-phase, two-parallel configuration from left to right.
[0029] In the stacked copper busbars of this invention, the upper ends of the DC bus copper busbar P+ and DC bus copper busbar P- are opened to avoid contact with the output pins of the IGBT module, and the shape of the openings is guaranteed to be consistent.
[0030] The present invention has the following beneficial effects:
[0031] 1) The copper busbars P+ and P- are parallel and tightly bonded through screw holes, positioning holes and insulating paper, but are electrically insulated. This reduces the distance between the IGBT module and the electrolytic capacitor, effectively reducing the presence of stray inductance. This structure also has a lower production cost.
[0032] 2) The P+ and P- busbars have the same shape in the IGBT module window section, and the distance from the IGBT module to the power-taking copper busbar hole side is close. For the dual parallel tube structure, the copper busbar structure is symmetrical, and its current sharing effect is better.
[0033] 3) The stacked busbar structure is clear and can be installed in layers, making installation simpler and more convenient, and facilitating subsequent maintenance and disassembly. Attached Figure Description
[0034] Figure 1 This is an exploded structural diagram of the stacked copper busbar structure of this utility model;
[0035] Figure 2 for Figure 1 Schematic diagram of the structure of the copper busbar P+ of the DC busbar;
[0036] Figure 3 for Figure 1 A schematic diagram of the structure of the DC busbar P-. Detailed Implementation
[0037] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.
[0038] like Figure 1 The diagram shown is a schematic representation of an embodiment of the stacked copper busbar of this utility model. The stacked copper busbar includes, from top to bottom: DC busbar P+7, insulating paper II6, electrolytic capacitor series copper busbar 5, insulating paper I4, DC busbar P-3, IGBT module 2, and electrolytic capacitor 1. Insulating paper II6 is located between DC busbar P+7 and DC busbar P-3, and insulating paper I4 is located between DC busbar P-3 and electrolytic capacitor series copper busbar 5. DC busbar P-3 and DC busbar P+7 are used for wiring.
[0039] The aforementioned stacked copper busbars have multiple screw holes that correspond to the positioning holes on each insulating paper, the pins of IGBT module 2 and electrolytic capacitor 1, allowing the DC bus copper busbars P-3 and P+7 to be close together without direct contact, effectively reducing the influence of stray inductance and lowering manufacturing costs.
[0040] like Figure 2As shown, the upper side of the DC bus copper bus P+7 is provided with an opening 701 corresponding to the IGBT module. The DC bus copper bus P+7 and the IGBT module 2 are provided with screw holes 702 for fixing. At the same time, there is a power supply screw hole 703 on the left side for power supply wiring for other circuits, and a power supply screw hole 704 on the right side for powering the DC bus copper bus P+. There is an electrolytic capacitor connection screw hole 705 on the lower side, which can fix the DC bus copper bus P+7 to the positive pin of the electrolytic capacitor 1.
[0041] like Figure 3 As shown, the upper side of the DC bus copper bus P-3 is provided with a window 302 corresponding to the IGBT module. The DC bus copper bus P-3 is provided with screw fixing holes 301 at the corresponding positions of the IGBT module 2. At the same time, there are power supply screw holes 303 for power supply wiring for other circuits on the left side, 305 is a power supply screw hole, which can supply power to the DC bus copper bus P-, and 304 is an electrolytic capacitor connection screw hole, which can fix the DC bus copper bus P- to the negative terminal pin of the electrolytic capacitor.
[0042] Specifically, the upper left side of the insulating paper II6 has a rollable structure, and a positioning hole is provided on its right side at the position of the power supply screw hole 704 of the DC bus copper bus P+7. The edge of the insulating paper II6 is at least 1cm larger than the edge of the DC bus copper bus P+7 to ensure good insulation between the DC bus copper bus P+7 and the DC bus copper bus P-3.
[0043] When assembling and using the stacked copper busbar, first fix the electrolytic capacitor 1 and IGBT module 2 on the mounting surface. Then, place the DC busbar P-3, insulating paper I 4, electrolytic capacitor series copper busbar 5, insulating paper II 6, and DC busbar P+7 on the fixed electrolytic capacitor 1 and IGBT module 2 in sequence. The screw fixing hole 702 on the upper side of the DC busbar P+7 corresponds to the positive power supply pin of the IGBT module 2, and the copper busbar at the window position should avoid other pins of the IGBT module 2. The screw hole 705 on the lower side of the electrolytic capacitor corresponds to the positive pin of the electrolytic capacitor 1. The screw fixing hole 301 on the upper side of the DC busbar P-3 corresponds to the negative power supply pin of the IGBT module 2, and the copper busbar at the window position should avoid other pins of the IGBT module 2. The screw hole 304 on the lower side of the electrolytic capacitor corresponds to the negative pin of the electrolytic capacitor 1.
[0044] When assembling and using the stacked copper busbars, in order to ensure accurate installation of the insulating paper and copper busbars, after installing the DC busbar P-3, screws can be screwed into the screw fixing holes 301 on its upper end and the IGBT module 2 to fix their relative positions. Then, the insulating paper and other copper busbars can be placed, thereby achieving a tight lock on multiple points on the copper busbars. The installation process is convenient and easy to disassemble and maintain.
[0045] To facilitate power draw from the busbars for other circuits, both DC busbar P+7 and DC busbar P-3 have two power draw screw holes on their left sides, which are staggered. During assembly, the power draw screw hole 303 on the left side of DC busbar P-3 should be buried under the bendable part on the left side of insulating paper II6 to ensure that the terminals are not directly connected.
[0046] The screw used at the power take-off screw hole 703 on the left side of the DC bus copper bus P+7 should be of appropriate length; otherwise, it may puncture the insulation paper II6, resulting in a decrease in its insulation.
[0047] The insulating paper material between DC bus copper bus P+7 and DC bus copper bus P-3 can be made of Nomic paper.
[0048] The upper window shapes of DC bus copper bus P+7 and DC bus copper bus P-3 are the same, and the distances from the power supply screw holes on the copper bus to the positive and negative power supply pins of IGBT module 2 are similar, resulting in good impedance matching. For IGBT parallel modules, their current sharing characteristics are good, which can effectively extend the service life of IGBT module 2.
[0049] The beneficial effects of this invention are as follows:
[0050] 1) The processing flow of the stacked copper busbar is convenient, and the components such as insulating paper, IGBT, electrolytic capacitor and busbar copper busbar are well matched with each other, which facilitates installation and maintenance.
[0051] 2) The copper busbars are parallel and tightly attached to each other through screw holes and positioning holes on the insulating paper, and are fixed to the IGBTs and electrolytic capacitors through screw holes. The parallel and tightly attached busbar structure can effectively reduce the stray inductance caused by wiring, and at the same time reduce the distance between the IGBT and the electrolytic capacitor, thus reducing the stray inductance of the busbar. This can effectively reduce the surge voltage generated when the IGBT power element is working, and the withstand voltage requirements of the electrolytic capacitor and IGBT can be appropriately relaxed.
[0052] 3) For IGBTs used in parallel, the distance from the IGBT to the positive and negative copper busbars is similar, and the impedance matching from the parallel tubes to the power supply busbar is better, which makes the current sharing effect of the parallel IGBTs better. When the IGBTs are working, the two parallel tubes bear similar current, which increases the service life of the IGBTs.
[0053] The above description is merely a specific embodiment of this utility model. It should be noted that the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.
Claims
1. A stacked copper busbar structure, characterized in that, The stacked copper bus structure includes a DC bus copper bus P+, insulating paper II, a series copper bus with electrolytic capacitors, insulating paper I, a DC bus copper bus P-, an IGBT module, and an electrolytic capacitor. The upper end of the DC bus copper bus P+ has screw holes for powering the upper bridge collector pin of the IGBT module; the upper end of the DC bus copper bus P- has screw holes for powering the lower bridge emitter pin of the IGBT module; both the DC bus copper bus P+ and DC bus copper bus P- have openings corresponding to the IGBT module; the IGBT module is connected to the IGBT module via the corresponding screw holes. The DC bus copper busbars P+ and P- are connected for power supply; the DC bus copper busbars P+ and P- are insulated and bonded together by insulating paper II placed in the middle; there are multiple electrolytic capacitors, and the pins of each electrolytic capacitor are connected in series and parallel to the corresponding screw holes on the series copper busbar; both the DC bus copper busbars P+ and P- are provided with electrolytic capacitor connection screw holes, which are respectively connected to the positive and negative pins of the electrolytic capacitors; the insulating paper I is used to isolate and insulate the DC bus copper busbar P- from the series copper busbar of the electrolytic capacitors.
2. The stacked copper busbar structure according to claim 1, characterized in that, The DC bus copper bus P+ is provided with a power supply screw hole for supplying power to the DC bus copper bus P+; the DC bus copper bus P- is provided with a power supply screw hole for supplying power to the DC bus copper bus P-.
3. The stacked copper busbar structure according to claim 2, characterized in that, The DC bus copper bus P+ and DC bus copper bus P- are respectively provided with staggered power supply connection screw holes.
4. The stacked copper busbar structure according to claim 3, characterized in that, Positioning holes are provided at the corresponding positions of the insulating paper II and the power take-off screw holes and power supply screw holes of the DC bus copper bus P+.
5. The stacked copper busbar structure according to claim 4, characterized in that, The upper left portion of the insulating paper II is a rollable part; the power supply screw hole of the DC bus copper busbar P- is located on the left side and is located below the rollable part of the insulating paper II during assembly.
6. The stacked copper busbar structure according to claim 5, characterized in that, The IGBT module adopts a three-phase, two-parallel arrangement.
7. The stacked copper busbar structure according to claim 6, characterized in that, The insulating paper II and insulating paper I are made of Nomic paper.