Crimping type high-voltage high-power resistor and packaging unit

Abstract

The invention discloses a crimping type high-voltage high-power resistor and a packaging unit, and relates to the technical field of power electronics, and the crimping type alloy foil resistor comprises an alloy foil; the first ceramic substrate, the lower electrode and the second heat dissipation bottom plate are sequentially stacked on one side of the alloy foil; the second ceramic substrate, the upper electrode and the first heat dissipation bottom plate are sequentially stacked on the other side of the alloy foil. Heat dissipation is carried out by fixing the first heat dissipation bottom plate and the second heat dissipation bottom plate, so that the resistor has the characteristic of double-sided heat dissipation, the heat dissipation area is doubled under the same volume, the heating power can be correspondingly doubled, and the power density is doubled. In the packaging unit, a spring piece and a flow deflector are fixedly connected to the crimping type high-voltage high-power resistor, and pressure contact is adopted, so that the problems that a traditional resistor welding spot falls off and the contact is not reliable are solved, the long-term operation reliability is improved, and the resistor cannot damage other surrounding components due to faults.

Description

Technical Field

[0001] The invention relates to the technical field of power electronics, and in particular to a crimped high-voltage and high-power resistor and a packaging unit. Background Art

[0002] The thyristor damping resistor is a key component of the DC converter valve, which plays a role in limiting the thyristor turn-on current and preventing the thyristor from abnormally shutting down during transient processes. During operation, the average power of the damping resistor reaches more than several kilowatts, and the transient power is several megawatts. Therefore, the power density of the damping resistor needs to be increased in a compact space.

[0003] One of the heat dissipation solutions for traditional damping resistors is direct water cooling, which soaks the wire-wound alloy resistance wire in deionized water and connects it to the external circuit through an electrode with a sealing ring, thereby achieving the purpose of increasing the power density. However, this solution has the risk of water leakage and electrode corrosion and requires an additional cooling device, which is not suitable for compact spaces such as thyristors. The second heat dissipation solution for traditional damping resistors is indirect water cooling, which fills insulating and heat-conducting media such as magnesium oxide around the wire-wound alloy resistance wire, and then wraps the outer layer with metal skin. The resistor is tube-mounted as a whole, and the whole is inserted into the radiator, and the heat is taken away by the water flow inside the radiator. This solution has the disadvantages of poor contact between the tubular resistor and the radiator and poor heat dissipation effect, and also requires an additional cooling device, which is not suitable for compact spaces such as thyristors. The third heat dissipation solution for traditional damping resistors is also indirect water cooling, which is a welded, multi-layer stacked alloy foil type, with an insulating heat dissipation substrate and a bottom plate stacked under the alloy foil resistor body, and the whole is sealed with potting silicone rubber. This resistor is single-sided heat dissipation, and there is a problem of low heat dissipation efficiency. Therefore, the resistor in the prior art has the problem of low heat dissipation efficiency in a compact space. Summary of the invention

[0004] In order to solve the problem that the heat dissipation efficiency of the resistor in the prior art is low in a compact space.

[0005] The purpose of the present invention is to adopt the following technical solutions to achieve:

[0006] In a first aspect, the present invention provides a crimped alloy foil resistor, comprising: an alloy foil;

[0007] A first ceramic substrate, a lower electrode and a second heat dissipation base plate sequentially stacked on one side of the alloy foil;

[0008] A second ceramic substrate, an upper electrode and a first heat dissipation base plate are sequentially stacked on the other side of the alloy foil.

[0009] Preferably, a first buffer sheet is pressed between the upper electrode and the first heat dissipation bottom plate, and a second buffer sheet is pressed between the lower electrode and the second heat dissipation bottom plate.

[0010] Preferably, a third copper sheet and a fourth copper sheet are fixed to the upper surface and the lower surface of the first ceramic substrate respectively.

[0011] Preferably, a first copper sheet and a second copper sheet are fixed to the upper surface and the lower surface of the second ceramic substrate respectively.

[0012] Preferably, it further comprises a ceramic shell, wherein the ceramic shell is potted with silicone rubber to integrally encapsulate the alloy foil, the first ceramic substrate, the second ceramic substrate, the upper electrode, the lower electrode, the first heat dissipation base plate and the second heat dissipation base plate.

[0013] Preferably, the first ceramic substrate and the second ceramic substrate have the same thickness.

[0014] Preferably, the first ceramic substrate and the second ceramic substrate are made of aluminum oxide or aluminum nitride.

[0015] Preferably, the first heat dissipation base plate and the second heat dissipation base plate have the same thickness.

[0016] In a second aspect, the present invention provides a packaging unit of a crimped high-voltage high-power resistor, characterized in that it comprises any one of the crimped high-voltage high-power resistors described above;

[0017] A plurality of the crimped high-voltage and high-power resistors are connected in parallel between the first electrode and the second electrode; a spring sheet and a guide sheet are fixedly connected to each crimped high-voltage and high-power resistor; and the spring sheet and the guide sheet are both connected to the first electrode.

[0018] Preferably, the spring sheet and the guide sheet are fixed to the first electrode and the crimped high-voltage and high-power resistor by welding.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] The invention provides a crimping type high-voltage and high-power resistor. A first ceramic substrate and a second ceramic substrate are respectively fixed on the upper and lower sides of an alloy foil. The first ceramic substrate and the second ceramic substrate are used to transfer the heat of the alloy foil. An upper electrode is fixed on the surface of the second ceramic substrate. A lower electrode is fixed on the surface of the first ceramic substrate to connect with an external circuit. Heat is dissipated by fixing a first heat dissipation bottom plate and a second heat dissipation bottom plate. Thus, the resistor has a double-sided heat dissipation feature. Under the same volume, the heat dissipation area is increased by 1 times, the heat generation power can be increased by 1 times accordingly, and the power density is also increased by 1 times.

[0021] The present invention provides a packaging unit for a crimped high-voltage and high-power resistor. A spring sheet and a guide sheet are fixedly connected to the crimped high-voltage and high-power resistor, and pressure contact is adopted to avoid the problems of traditional resistor welding points falling off and unreliable contact, thereby improving long-term operating reliability, and the resistor will not damage other surrounding components due to a malfunction. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic structural diagram of a crimped alloy foil resistor in Example 1 of the present invention;

[0023] Figure 2 This is a schematic diagram of parallel press-fitting of packaging units of a press-fit type high-voltage and high-power resistor in Example 2 of the present invention;

[0024] In the figure: alloy foil 1, first ceramic substrate 2, second ceramic substrate 3, upper electrode 4, lower electrode 5, first buffer sheet 6, second buffer sheet 7, first copper sheet 8, second copper sheet 9, third copper sheet 10, fourth copper sheet 11, first heat dissipation base plate 12, second heat dissipation base plate 13, crimped alloy foil resistor 14, spring sheet 15, guide sheet 16, first electrode 17, second electrode 18. DETAILED DESCRIPTION

[0025] In the following, only some exemplary embodiments are briefly described. As those skilled in the art will appreciate, the described embodiments may be modified in various ways without departing from the spirit or scope of the present invention. Therefore, the drawings and descriptions are considered to be exemplary and non-restrictive in nature.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0027] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or a communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0030] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0031] It should also be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0032] It should be further understood that the term "and / or" used in the present description and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0033] Various structural schematic diagrams of the embodiments disclosed in the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified and some details may be omitted for the purpose of clear expression. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships therebetween are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs.

[0034] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0035] Embodiment 1:

[0036] The present invention provides a crimped alloy foil resistor, comprising: an alloy foil 1; a first ceramic substrate 2, a lower electrode 5 and a second heat dissipation base plate 13 stacked in sequence on one side of the alloy foil 1; a second ceramic substrate 3, an upper electrode 4 and a first heat dissipation base plate 12 stacked in sequence on the other side of the alloy foil 1.

[0037] In the present invention, the first ceramic substrate 2 and the second ceramic substrate 3 are respectively fixed on the upper and lower sides of the alloy foil 1, the first ceramic substrate 2 and the second ceramic substrate 3 are used to transfer the heat of the alloy foil, and an upper electrode 4 is fixed on the surface of the second ceramic substrate; a lower electrode 5 is fixed on the surface of the first ceramic substrate to connect with an external circuit, and heat is dissipated by fixing the first heat dissipation base plate 12 and the second heat dissipation base plate 13, so that the resistor has a double-sided heat dissipation feature, the heat dissipation area is increased by 1 times under the same volume, the heating power can be increased by 1 times accordingly, and the power density is also increased by 1 times.

[0038] Specifically, Figure 1 As shown, a crimped alloy foil resistor in an embodiment of the present invention includes an alloy foil 1, a first ceramic substrate 2, a second ceramic substrate 3, an upper electrode 4, a lower electrode 5, a first buffer sheet 6, a second buffer sheet 7, a first copper sheet 8, a second copper sheet 9, a third copper sheet 10, a fourth copper sheet 11, a first heat dissipation base plate 12 and a second heat dissipation base plate 13.

[0039] The first ceramic substrate 2 and the second ceramic substrate 3 are fixed to the upper and lower sides of the alloy foil 1. In the embodiment of the present invention, the alloy foil is preferably made of nickel-chromium alloy with a thickness ranging from 100 μm to 1000 μm. The alloy foil 1 is the main heat source in the resistor, and heat is dissipated on both sides through the first ceramic substrate 2 and the second ceramic substrate 3 on the upper and lower sides.

[0040] The first ceramic substrate 2 and the second ceramic substrate 3 are used for insulation and heat dissipation; the present invention is a series resistor, and multiple ceramic substrates can be used for insulation between each branch resistor. The first ceramic substrate 2 and the second ceramic substrate 3 have the same thickness. The first ceramic substrate 2 and the second ceramic substrate 3 are made of aluminum oxide or aluminum nitride. The thickness of the first ceramic substrate 2 and the second ceramic substrate 3 is less than 1 mm.

[0041] Specifically, in the embodiment of the present invention, the upper electrode 4 is printed on the surface of the second ceramic substrate 3. The lower electrode 5 is printed on the surface of the first ceramic substrate 2. The upper electrode 4 and the lower electrode 5 are connected to the external circuit as resistance terminals. In the embodiment of the present invention, the material of the upper electrode 4 and the lower electrode 5 are both made of copper or copper alloy, and the thickness of the upper electrode 4 and the lower electrode 5 is the same, and the thickness of the upper electrode 4 and the lower electrode 5 is within 1 mm.

[0042] Specifically, in order to match the thermal expansion coefficients of different materials, in the embodiment of the present invention, a first buffer sheet 6 is fixed between the upper electrode 4 and the first heat dissipation base plate 12, and a second buffer sheet 7 is fixed between the lower electrode 5 and the second heat dissipation base plate 13. The first buffer sheet 6 and the second buffer sheet 7 are both made of molybdenum, and the thickness of the first buffer sheet 6 and the second buffer sheet 7 is within 1 mm. The first buffer sheet 6 and the second buffer sheet 7 are used to balance the thermal expansion coefficients between the materials so that no gap or crack occurs in the materials when the temperature changes.

[0043] In the embodiment of the present invention, the first buffer sheet 6 is placed on the first heat dissipation base plate 12, and the second buffer sheet 7 is placed on the second heat dissipation base plate 13. The first heat dissipation base plate 12 and the second heat dissipation base plate 13 are also connected to the external circuit as resistance terminals, and at the same time serve as external heat dissipation base plates. Among them, the upper electrode 4 and the lower electrode 5 are used to connect to the external circuit, and the first heat dissipation base plate 12 and the second heat dissipation base plate 13 play a role in strengthening mechanical strength and conductivity. The first buffer sheet 6 is connected to the upper electrode 4 and the first heat dissipation base plate 12 by crimping (i.e. pressure contact); the second buffer sheet 7 is connected to the lower electrode 5 and the second heat dissipation base plate 13 by crimping (i.e. pressure contact); the first heat dissipation base plate 12 and the second heat dissipation base plate 13 are made of aluminum alloy, and the thickness of the first heat dissipation base plate 12 and the second heat dissipation base plate 13 ranges from 3mm to 5mm.

[0044] Specifically, the upper and lower surfaces of the first ceramic substrate 2 are respectively covered with a first copper sheet 8 and a second copper sheet 9, and the upper and lower surfaces of the second ceramic substrate 3 are respectively covered with a third copper sheet 10 and a fourth copper sheet 11. In the embodiment of the present invention, the copper sheets are covered on the surface of the ceramic substrate to evenly transfer heat, offset the upper and lower expansion, and at the same time, to connect the resistors to play an intermediate coupling role.

[0045] In the embodiment of the present invention, the first copper sheet 8, the second copper sheet 9, the third copper sheet 10 and the fourth copper sheet 11 have the same thickness; wherein the thickness of the first copper sheet 8, the second copper sheet 9, the third copper sheet 10 and the fourth copper sheet 11 is less than 1 mm.

[0046] Specifically, in the embodiment of the present invention, the alloy foil 1, the first ceramic substrate 2, the second ceramic substrate 3, the upper electrode 4, the lower electrode 5, the first buffer sheet 6, the second buffer sheet 7, the first copper sheet 8, the second copper sheet 9, the third copper sheet 10, the fourth copper sheet 11, the first heat dissipation base plate 12 and the second heat dissipation base plate 13 are placed in a ceramic housing as a whole, and the internal potting silicone rubber of the ceramic housing is encapsulated as a whole, and the ceramic housing is insulated externally. Reliable contact between the materials inside the resistor is achieved by applying opposite pressing forces to the first heat dissipation base plate 12 and the second heat dissipation base plate 13. The first heat dissipation base plate 12 and the second heat dissipation base plate 13 are connected to the external circuit by crimping or by arranging wiring terminals thereon.

[0047] A processing process of a crimped alloy foil resistor in an embodiment of the present invention specifically includes:

[0048] The alloy foil 1 is pasted on the first ceramic substrate 2 as a resistance wire. The second ceramic substrate 3 is pasted on the alloy foil 1;

[0049] Among them, the upper electrode 4 is printed on the second ceramic substrate 3, and the lower electrode 5 is printed under the first ceramic substrate 2. The upper electrode 4 and the lower electrode 5 are connected to the external circuit as resistance terminals. The third copper sheet 10 and the fourth copper sheet 11 are respectively laid and fixed on the upper surface and the lower surface of the first ceramic substrate 2. The first copper sheet 8 and the second copper sheet 9 are respectively laid and fixed on the upper surface and the lower surface of the second ceramic substrate 3.

[0050] The first buffer sheet 6 is connected to the upper electrode surface 4, and the second buffer sheet 7 is connected to the surface of the lower electrode 5, so as to match the thermal expansion coefficients of different materials.

[0051] The first heat dissipation base plate 12 is connected to one end of the first buffer plate 6, and the second heat dissipation base plate 13 is connected to one end of the second buffer plate 7. The first heat dissipation base plate 12 and the second heat dissipation base plate 13 are connected to the external circuit as resistance terminals and also serve as external heat dissipation base plates.

[0052] The alloy foil 1, the first ceramic substrate 2, the second ceramic substrate 3, the first buffer sheet 6, the second buffer sheet 7, the first heat dissipation base plate 12 and the second heat dissipation base plate 13 are packaged as a whole, with silicone rubber encapsulated inside and ceramics contained outside to achieve external insulation.

[0053] A relative pressing force is applied to the first heat dissipation base plate 12 and the second heat dissipation base plate 13 to achieve reliable pressure contact between the materials inside the resistor.

[0054] The resistor in the embodiment of the present invention solves the reliability problem of traditional resistors in high-power and high-temperature environments by pasting the alloy foil 1 as the resistance wire on the ceramic substrate and adopting a multi-layer structure design. The present invention cleverly uses a buffer sheet to match the thermal expansion coefficients of different materials, and uses the base plate as a dual-functional component for heat dissipation and electrical connection. The heat dissipation performance is further improved by covering the surface of the ceramic substrate with a copper layer. Finally, an overall packaging process of silicone rubber potting and ceramic outsourcing is adopted to achieve excellent insulation performance. The application of the press-fit process ensures reliable contact between the internal materials, significantly improves the power density, temperature stability and long-term reliability of the resistor, and is suitable for various harsh working environments.

[0055] Embodiment 2:

[0056] The present invention based on the same inventive concept further provides a packaging unit of a crimped alloy foil resistor, comprising a first electrode 17 and a second electrode 18 .

[0057] Several of the crimped high-voltage and high-power resistors 14 are connected in parallel between the first electrode 17 and the second electrode 18 ; a spring sheet 15 and a guide sheet 16 are fixedly connected to each crimped high-voltage and high-power resistor 14 ; the spring sheet 15 and the guide sheet 16 are both connected to the first electrode 17 .

[0058] Specifically, to increase the power of a single resistor, several Figure 1 The resistor subunit (i.e., the crimped high-voltage high-power resistor 14) is integrally pressed into a package unit ( Figure 2 As shown), each subunit is electrically connected in parallel. That is, a number of resistor subunits are placed on the first electrode 17, and the first heat dissipation base plate 12 is in contact with the first electrode 17 for electrical connection. At the same time, in order to ensure pressure balance, a spring sheet 15 is provided on each subunit, one end of the spring sheet 15 is in contact with the second electrode 18, and the other end of the spring sheet 15 is in contact with the second heat dissipation base plate 13. Multiple parallel units require the use of spring sheets, which is used to balance the pressure of each unit to avoid the situation where some units are tightly fitted and some have gaps. The guide plate 16 is installed on the side of the spring sheet 15, and the guide plate 16 is connected to the second electrode 18 and the second heat dissipation base plate 13 for passing current. The guide plate 16 is welded to the resistor subunit 14 and the external electrode, and the spring sheet is also fixed by welding.

[0059] The resistor of the present invention has the characteristics of double-sided heat dissipation, which increases the power density by 1 times. At the same time, the layers of materials inside the resistor adopt pressure contact, which avoids the problems of traditional resistor solder joints falling off and unreliable contact, and improves long-term operation reliability. In addition, the resistor will not damage other surrounding components due to failure.

[0060] In addition, it should be understood that although this specification is described in accordance with the implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other implementation modes that can be understood by those skilled in the art. The above content is only to illustrate the technical idea of ​​the present invention, and cannot be used to limit the protection scope of the present invention. Any changes made on the basis of the technical solution according to the technical idea proposed by the present invention shall fall within the protection scope of the claims of the present invention.

Claims

1. A crimped alloy foil resistor, characterized in that: include: Alloy foil(1); A first ceramic substrate (2), a lower electrode (5) and a second heat dissipation base plate (13) stacked in sequence on one side of the alloy foil (1); A second ceramic substrate (3), an upper electrode (4) and a first heat dissipation base plate (12) are sequentially stacked on the other side of the alloy foil (1).

2. A crimped alloy foil resistor according to claim 1, characterized in that: A first buffer sheet (6) is pressed between the upper electrode (4) and the first heat dissipation bottom plate (12), and a second buffer sheet (7) is pressed between the lower electrode (5) and the second heat dissipation bottom plate (13).

3. A crimped alloy foil resistor according to claim 1, characterized in that: A third copper sheet (10) and a fourth copper sheet (11) are fixed to the upper surface and the lower surface of the first ceramic substrate (2), respectively.

4. A crimped alloy foil resistor according to claim 1, characterized in that: A first copper sheet (8) and a second copper sheet (9) are respectively fixed to the upper surface and the lower surface of the second ceramic substrate (3).

5. The crimped alloy foil resistor according to claim 1, characterized in that: It also comprises a ceramic shell, wherein the ceramic shell is filled with silicone rubber to integrally encapsulate the alloy foil (1), the first ceramic substrate (2), the second ceramic substrate (3), the upper electrode (4), the lower electrode (5), the first heat dissipation base plate (12) and the second heat dissipation base plate (13).

6. A crimped alloy foil resistor according to claim 1, characterized in that: The first ceramic substrate (2) and the second ceramic substrate (3) have the same thickness.

7. A crimped alloy foil resistor according to claim 1, characterized in that: The first ceramic substrate (2) and the second ceramic substrate (3) are made of aluminum oxide or aluminum nitride.

8. The crimped alloy foil resistor according to claim 1, characterized in that: The first heat dissipation base plate (12) and the second heat dissipation base plate (13) have the same thickness.

9. A packaging unit for a crimped high-voltage and high-power resistor, characterized in that: A crimped high-voltage and high-power resistor (14) comprising the crimped high-voltage and high-power resistor (14) as claimed in any one of claims 1 to 8; A plurality of the crimped high-voltage and high-power resistors (14) are connected in parallel between a first electrode (17) and a second electrode (18); a spring sheet (15) and a guide sheet (16) are fixedly connected to each crimped high-voltage and high-power resistor (14); and the spring sheet (15) and the guide sheet (16) are both connected to the first electrode (17).

10. The packaging unit of a crimped high-voltage and high-power resistor according to claim 9, characterized in that: The spring sheet (15) and the guide sheet (16) are fixed on the first electrode (17) and the crimped high-voltage and high-power resistor (14) by welding.

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