High voltage pre-charge resistor with overload protection

Abstract

The application discloses a high-voltage pre-charging resistor with an overload protection device, and relates to the technical field of resistors.The high-voltage pre-charging resistor with the overload protection device comprises a shell, a carbon ceramic resistor body and a foot piece, the shell is provided with a containing cavity, the carbon ceramic resistor body is arranged in the containing cavity, the foot piece comprises a first foot piece and at least one second foot piece, one end of the first foot piece is connected with the carbon ceramic resistor body, one end of the second foot piece is connected with the other end of the first foot piece through a fuse, the other end of the second foot piece is located outside the shell and is used for being electrically connected with an external device, and the one end of the second foot piece, the first foot piece and the fuse are all arranged in the containing cavity.Through the arrangement, the pre-charging resistor can melt the fuse in the case that the pre-charging resistor is used for a long time and heat is accumulated, so that the main body, i.e., the carbon ceramic resistor body, of the high-voltage pre-charging resistor with the overload protection device is prevented from being damaged, and the safety and pulse resistance performance of the pre-charging resistor during use are improved.

Description

Technical Field

[0001] This invention relates to the field of resistor technology, and more particularly to a high-voltage pre-charge resistor with an overload protection device. Background Technology

[0002] The electrical system of the battery distribution box within a power battery pack typically integrates main positive control circuit, main negative control circuit, pre-charge circuit, and voltage and current detection circuits. It includes electrical components such as main positive contactors, main negative contactors, pre-charge contactors, pre-charge resistors, shunts, and battery sensors. Since the power battery pack needs to charge its capacitors at the initial stage of each power-on cycle, excessive charging current, if not limited, will severely impact rectifier components and other parts. Therefore, a pre-charge resistor is required for current limiting.

[0003] Currently, common pre-charge resistors, such as cement resistors, have poor short-circuit withstand strength and instantaneous energy impact resistance. Excessive heat during a short circuit may lead to fire or other dangerous situations, resulting in low safety when using such pre-charge resistors. Summary of the Invention

[0004] This invention aims to at least solve one of the technical problems existing in the prior art. To this end, this invention proposes a high-voltage pre-charge resistor with an overload protection device, which can improve the safety and pulse tolerance performance of the pre-charge resistor during use.

[0005] A high-voltage pre-charge resistor with an overload protection device according to an embodiment of the present invention includes:

[0006] The outer casing has a receiving cavity;

[0007] A carbon ceramic resistor is disposed in the receiving cavity;

[0008] The lead includes a first lead and at least one second lead. One end of the first lead is connected to the carbon ceramic resistor. One end of the second lead is connected to the other end of the first lead via a fuse. The other end of the second lead is located outside the housing and is used for electrical connection with external devices. One end of the second lead, the first lead, and the fuse are all located in the receiving cavity.

[0009] The high-voltage pre-charge resistor with overload protection device according to embodiments of the present invention has at least the following beneficial effects: The present invention is a high-voltage pre-charge resistor with overload protection device based on a carbon ceramic resistor. By setting a fuse as an overload protection device, the safety of the pre-charge resistor during use is improved. At the same time, using a carbon ceramic resistor as the main body improves the pulse withstand performance of the pre-charge resistor and allows the pre-charge resistor to be used under high voltage conditions. Specifically, the second lead is connected to the carbon ceramic resistor through the fuse and the first lead, so that the pre-charge resistor can melt the fuse under the condition of long overload time and heat accumulation, thereby protecting the main body of the high-voltage pre-charge resistor with overload protection device, namely the carbon ceramic resistor, from damage, and thus improving the safety of the pre-charge resistor during use.

[0010] According to some embodiments of the present invention, a potting layer is formed within the receiving cavity, the potting layer being used to pot one end of the carbon ceramic resistor, the first lead, and the second lead.

[0011] According to some embodiments of the present invention, the potting layer is made of a high-temperature resistant material.

[0012] According to some embodiments of the present invention, the lead plate further includes a third lead plate, one end of which is connected to the side of the carbon ceramic resistor away from the first lead plate, the potting layer is also used to pot one end of the third lead plate, the other end of which is located outside the housing, and the other end of which is electrically connected to an external device.

[0013] According to some embodiments of the present invention, at least one first through groove is provided at the other end of the third foot piece.

[0014] According to some embodiments of the present invention, the high-voltage pre-charge resistor with overload protection device further includes a support plate, the fuse is attached to one side of the support plate, one end of the second lead is attached to the other side of the support plate, and the potting layer is also used to pot the support plate.

[0015] According to some embodiments of the present invention, the support plate is provided with a first through hole and at least one second through hole, one end of the fuse passing through the second through hole is connected to one end of the second foot piece, and the other end of the first foot piece is connected to the other end of the fuse at the first through hole.

[0016] According to some embodiments of the present invention, two second foot pieces are provided, and both second foot pieces are provided on the other side of the support plate.

[0017] According to some embodiments of the present invention, a second through groove is provided at the other end of each of the two second feet.

[0018] According to some embodiments of the present invention, the fuse is made of nickel-chromium alloy wire.

[0019] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The accompanying drawings are provided to further understand the technical solutions of the present invention and constitute a part of the specification. They are used together with the embodiments of the present invention to explain the technical solutions of the present invention and do not constitute a limitation on the technical solutions of the invention.

[0021] Figure 1 This is a front view of the assembled carbon ceramic resistor provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram of the connection between the first lead plate, the second lead plate, and the fuse provided in an embodiment of the present invention;

[0023] Figure 3 This is a side view of the assembled carbon ceramic resistor provided in an embodiment of the present invention;

[0024] Figure 4 This is a schematic diagram of a high-voltage pre-charge resistor with an overload protection device provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the potting layer provided in an embodiment of the present invention.

[0026] Figure label:

[0027] 100 high-voltage pre-charge resistor with overload protection device;

[0028] 110 housing, 120 carbon ceramic resistor, 130 potting layer, 140 first lead, 150 fuse;

[0029] Second foot piece 160, second through groove 161;

[0030] Third foot piece 170, first through groove 171;

[0031] Support plate 180, first through hole 181, second through hole 182. Detailed Implementation

[0032] Embodiments of the present invention are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0033] In the description of this invention, it should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, features defined with "first" or "second" may explicitly or implicitly include one or more of those features.

[0034] In the description of this invention, unless otherwise stated, "a plurality of" means two or more. It should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, it can be a fixed connection or a movable connection, a detachable connection or a non-detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection, or a connection that allows communication between the two components; it can be a direct connection or an indirect connection through an intermediate medium; it can be a connection within two elements, an indirect connection, or an interaction between two elements.

[0035] In the description of this invention, unless otherwise explicitly defined, terms such as setting, installing, and connecting should be interpreted broadly. Those skilled in the art can understand the specific meaning of the above terms in the invention according to the specific circumstances.

[0036] The electrical system of the battery distribution box within a power battery pack typically integrates main positive control circuit, main negative control circuit, pre-charge circuit, and voltage and current detection circuits. It includes electrical components such as main positive contactors, main negative contactors, pre-charge contactors, pre-charge resistors, shunts, and battery sensors. Since the power battery pack needs to charge its capacitors at the initial stage of each power-on cycle, excessive charging current, if not limited, will severely impact rectifier components and other parts. Therefore, a pre-charge resistor is required for current limiting.

[0037] Currently, common pre-charge resistors, such as cement resistors, have poor short-circuit withstand strength and instantaneous energy impact resistance, resulting in low safety during use.

[0038] Based on this, embodiments of the present invention provide a high-voltage pre-charge resistor 100 with an overload protection device, which can improve the safety and pulse tolerance performance of the pre-charge resistor during use.

[0039] The following is for reference. Figures 1 to 5 A high-voltage pre-charge resistor 100 with an overload protection device is described according to an embodiment of the present invention.

[0040] Reference Figures 1 to 5The high-voltage pre-charge resistor 100 with overload protection device includes: a housing 110, a carbon ceramic resistor 120, and leads. The housing 110 has a receiving cavity, in which the carbon ceramic resistor 120 is disposed. The leads include a first lead 140 and at least one second lead 160. One end of the first lead 140 is connected to the carbon ceramic resistor 120, and one end of the second lead 160 is connected to the other end of the first lead 140 through a fuse 150. The other end of the second lead 160 is located outside the housing 110 and is used for electrical connection with external equipment. One end of the second lead 160, the first lead 140, and the fuse 150 are all disposed in the receiving cavity.

[0041] This invention relates to a high-voltage pre-charge resistor 100 with an overload protection device, primarily based on a carbon ceramic resistor 120. By incorporating a fuse 150 as an overload protection device, the safety of the pre-charge resistor during use is improved. Furthermore, the use of the carbon ceramic resistor 120 as the main body enhances the pulse withstand performance of the pre-charge resistor. Specifically, the second lead 160 is connected to the carbon ceramic resistor 120 via the fuse 150 and the first lead 140, allowing the fuse 150 to melt under prolonged overload conditions and heat accumulation. This protects the main body of the high-voltage pre-charge resistor 100 with overload protection, namely the carbon ceramic resistor 120, from damage, thereby improving the safety of the pre-charge resistor during use.

[0042] In related technologies, common pre-charge resistors, such as cement-encapsulated resistors, have poor short-circuit withstand and transient energy surge resistance, making them essentially unsuitable for high voltage and other harsh conditions. This invention uses a small-volume cylindrical carbon ceramic resistor 120 as the main body of a high-voltage pre-charge resistor 100 with overload protection, enabling the high-voltage pre-charge resistor 100 with overload protection to be suitable for high voltage and other harsh conditions. Specifically, the carbon ceramic resistor 120 has a stronger overload capacity than other types of resistors, enhancing the transient pulse resistance of the pre-charge resistor. Using the carbon ceramic resistor 120 also allows the overall size of the pre-charge resistor to be controlled within a certain range, and the ceramic shell of the carbon ceramic resistor 120 increases its insulation performance. The use of a fuse 150 as an overload protection device improves the safety of the pre-charge resistor under extreme conditions (such as long overload time and heat accumulation).

[0043] In some embodiments, a second lead 160 is provided, one end of which is connected to the other end of the first lead 140 via a fuse 150 and is located in a receiving cavity, while the other end of the second lead 160 is located outside the housing 110, so that the carbon ceramic resistor 120 can be connected to an external device via the second lead 160; in another embodiment, two second leads 160 are provided, which are connected in parallel, one end of each of the two second leads 160 is connected to the other end of the first lead 140 via a fuse 150 and is located in a receiving cavity, while the other ends of each of the two second leads 160 are located outside the housing 110. When using the high-voltage pre-charge resistor 100 with overload protection, one end of each of the two second leads 160 is connected to the carbon ceramic resistor 120 via the fuse 150 and the first lead 140, while the other end is connected to an external device. This arrangement ensures that the fuse 150 can be successfully blown in the event of prolonged overload and heat accumulation, thereby protecting the main body of the pre-charge resistor, namely the carbon ceramic resistor 120, from damage and ensuring the safety of the pre-charge resistor during use.

[0044] It should be noted that in this embodiment, the carbon ceramic resistor 120 is cylindrical; in other embodiments, the carbon ceramic resistor 120 may also be other shapes, and is not limited to the embodiments of the present invention.

[0045] It should be noted that one end of the first lead 140 is connected to the carbon ceramic resistor 120, and the other end is connected to the other end of the fuse 150 by solder. One end of the second lead 160 is also soldered to one end of the fuse 150, and is connected to the carbon ceramic resistor 120 through the fuse 150, the first lead 140, and the fuse 150.

[0046] It should be noted that fuse 150 is made of metal wire.

[0047] It should be noted that the outer shell 110 can be cuboid, cube, or other shapes.

[0048] Reference Figure 5 It is understood that a potting layer 130 is formed within the cavity, which is used to pot one end of the carbon ceramic resistor 120, the first lead 140, and the second lead 160. By setting the potting layer 130, the relative positions of one end of the carbon ceramic resistor 120, the first lead 140, and the second lead 160 are fixed.

[0049] It should be noted that the potting material is poured into the cavity and submerges the portion of the carbon ceramic resistor 120, the first lead 140, and the second lead 160 connected to the first lead 140 via the fuse 150. This results in the potting layer 130 covering the portion of the carbon ceramic resistor 120, the first lead 140, and the second lead 160 connected to the first lead 140 via the fuse 150. After curing, the potting layer 130 is connected to one end of each of the carbon ceramic resistor 120, the first lead 140, and the second lead 160.

[0050] In some embodiments, the potting layer 130 can be formed by pouring and curing the potting material in one go to speed up the pouring process and increase the production speed of the carbon ceramic resistor 120. In other embodiments, the potting layer 130 can also be formed by pouring and curing the potting material multiple times to expel air from the cavity, reduce air bubbles inside the potting layer 130, and prevent the air inside the air bubbles from expanding due to heat during the use of the carbon ceramic resistor 120, thereby improving the potting layer 130's resistance to high and low temperature shocks. When the potting layer 130 is formed by pouring and curing the potting material multiple times, the potting material inside the outer shell 110 needs to be heated after each pour.

[0051] It should be noted that the potting layer 130, by encapsulating the carbon ceramic resistor 120, the first lead 140, the fuse 150, and the second lead 160 within it, fixes the relative position of the carbon ceramic resistor 120 and the lead, making the connection between the first lead 140 and the carbon ceramic resistor 120, the connection between one end of the fuse 150 and the second lead 160, and the connection between the other end of the fuse 150 and the first lead 140 more robust. This prevents the connection from cracking due to high and low temperature shocks, improves the stability of the connection between the first lead 140 and the carbon ceramic resistor 120, the connection between the other end of the fuse 150 and the first lead 140, and the connection between one end of the fuse 150 and the second lead 160, thereby enhancing safety.

[0052] Understandably, the potting layer 130 is made of high-temperature resistant material.

[0053] It should be noted that the potting layer 130 is specifically formed by pouring liquid high-temperature resistant material into the receiving cavity and submerging the portion of the carbon ceramic resistor 120, the first lead 140, the second lead 160, and the fuse 150. In some embodiments, the potting layer 130 can be formed by pouring and curing liquid high-temperature resistant material in one go to speed up the pouring process and increase the production speed of the carbon ceramic resistor 120. In other embodiments, the potting layer 130 can also be formed by pouring and curing liquid high-temperature resistant material multiple times to expel air from the receiving cavity, reduce air bubbles inside the potting layer 130, and prevent the air inside the air bubbles from expanding due to heat during the use of the carbon ceramic resistor 120, thereby improving the potting layer 130's resistance to high and low temperature shocks. Specifically, the potting layer 130 is made of epoxy resin. When the potting layer 130 is formed by pouring and curing potting material multiple times, the high-temperature resistant material inside the outer shell 110 needs to be heated after each pouring.

[0054] Reference Figures 3 to 5 It is understood that the lead plate also includes a third lead plate 170. One end of the third lead plate 170 is connected to the side of the carbon ceramic resistor 120 away from the first lead plate 140. The potting layer 130 is also used to pot one end of the third lead plate 170. The other end of the third lead plate 170 is located outside the housing 110. The other end of the third lead plate 170 is electrically connected to an external device.

[0055] It should be noted that the second lead 160 and the third lead 170 are located on opposite sides of the carbon ceramic resistor 120. The second lead 160 is connected to the carbon ceramic resistor 120 via the fuse 150 and the first lead 140, and the third lead 170 is connected to the carbon ceramic resistor 120. The corresponding arrangement of the second and third leads 160 facilitates the connection of the carbon ceramic resistor 120 to external devices via the second and third leads 170. Specifically, the second and third leads 160 are connected to the positive and negative terminals of the carbon ceramic resistor 120, respectively, facilitating the installation and use of the pre-charge resistor.

[0056] It should be noted that the potting material is poured into the cavity and submerges the portion where the carbon ceramic resistor 120 and the third lead 170 are connected to the carbon ceramic resistor 120, so that the potting layer 130 covers the portion where the carbon ceramic resistor 120 and the third lead 170 are connected to the carbon ceramic resistor 120. After curing, the potting layer 130 is connected to the portions where the carbon ceramic resistor 120 and the third lead 170 are connected to the carbon ceramic resistor 120.

[0057] It should be noted that the potting layer 130, by covering the carbon ceramic resistor 120 and the portion where the third lead 170 is connected to the carbon ceramic resistor 120, fixes the relative position of the carbon ceramic resistor 120 and the lead, making the connection between the third lead 170 and the carbon ceramic resistor 120 more secure, preventing the connection from cracking due to high and low temperature shocks, improving the stability of the connection between the third lead 170 and the carbon ceramic resistor 120, and enhancing safety.

[0058] Reference Figure 3 It is understood that at least one first through slot 171 is provided at the other end of the third pin 170. The first through slot 171 is provided on the third pin 170 so that the third pin 170 can be connected to an external device through the first through slot 171.

[0059] In this embodiment, refer to Figure 3 Two first through slots 171 are provided at the other end of the third foot piece 170, and both first through slots 171 are U-shaped so that the third foot piece 170 can be connected to external devices through the U-shaped first through slots 171. In other embodiments, in order to facilitate the connection between the third foot piece 170 and other external components, other numbers of first through slots 171 can also be provided on the third foot piece 170. The first through slots 171 can also be set in other shapes, and are not limited to the embodiments of the present invention.

[0060] Reference Figure 2 It is understood that the high-voltage pre-charge resistor 100 with overload protection also includes a support plate 180, a fuse 150 attached to one side of the support plate 180, one end of the second lead plate 160 attached to the other side of the support plate 180, and a potting layer 130 used to pot the support plate 180. The support plate 180 is provided to facilitate fixing the positions of the fuse 150, the first lead plate 140, and the second lead plate 160.

[0061] In this embodiment, one end of the fuse 150 is soldered to one end of the second lead 160 on the other side of the support plate 180, and the other end is soldered to the other end of the first lead 140 on one side of the support plate 180.

[0062] It should be noted that the support plate 180 can be a cube, a cuboid, or other shapes. This embodiment of the invention does not limit the shape.

[0063] Reference Figure 1 and Figure 2It is understood that the support plate 180 has a first through hole 181 and at least one second through hole 182. One end of the fuse 150 passes through the second through hole 182 and is connected to one end of the second lead plate 160. The other end of the first lead plate 140 is connected to the other end of the fuse 150 at the first through hole 181. The first through hole 181 and the second through hole 182 are provided to facilitate the connection of the fuse 150 to the first lead plate 140 and the second lead plate 160 respectively by soldering.

[0064] In some embodiments, refer to Figure 2 Two fuses 150 are attached to the support plate 180. The support plate 180 has a first through hole 181 and two second through holes 182. The first through hole 181 and the two second through holes 182 are respectively located at both ends of the support plate 180. One end of each fuse 150 passes through the two second through holes 182 and is soldered to the second lead plate 160 by soldering. The other end is soldered to the first lead plate 140 at the first through hole 181.

[0065] Reference Figure 1 and Figure 2 It is understandable that there are two second pins 160, both located on the other side of the support plate 180. Having two second pins 160 allows for easy replacement of the other pin if one fails, thus ensuring the normal operation of the circuit.

[0066] It should be noted that each of the two second pins 160 is provided with a fuse 150, and the two second pins 160 and the two second through holes 182 corresponding to the two fuses 150 are connected by solder.

[0067] Reference Figure 2 It is understandable that the other end of each of the two second feet 160 is provided with a second through slot 161. The second through slot 161 is provided on the second feet 160 so that the second feet 160 can be connected to external devices through the second through slot 161.

[0068] In this embodiment, the second through slots 161 on both second pins 160 are U-shaped so that the second pins 160 can be connected to external devices through the U-shaped second through slots 161. In other embodiments, the shape of the second pins 160 and the shape of the second through slots 161 of the second pins 160 can be set to match the shape of different external devices so that the second pins 160 can be connected to the external devices, thereby facilitating the installation and use of the precharge resistor.

[0069] It is understandable that the material of fuse 150 is nickel-chromium alloy wire.

[0070] It should be noted that the present invention uses nickel-chromium alloy wire as the material of fuse 150 mainly because nickel-chromium alloy wire has high resistivity, generates more heat under the same conditions, and has a low melting point. When the current in the circuit is too large, it is easy to melt, thereby improving the safety of the pre-charge resistor under extreme conditions (such as long overload time and heat accumulation).

[0071] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0072] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention.

[0073] Although embodiments of the invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A high voltage pre-charge resistor with overload protection, characterized in that, The application relates to a high-voltage pre-charging resistor with overload protection, which comprises the following parts: an outer shell provided with a containing cavity; a carbon ceramic resistor arranged in the containing cavity; a foot piece comprising a first foot piece and at least one second foot piece, one end of the first foot piece being connected with the carbon ceramic resistor, one end of the second foot piece being connected with the other end of the first foot piece through a fuse, the other end of the second foot piece being arranged outside the outer shell and used for electrically connecting with external equipment, and the one end of the second foot piece, the first foot piece and the fuse being arranged in the containing cavity; a pouring layer formed in the containing cavity and used for pouring the carbon ceramic resistor, the first foot piece and the one end of the second foot piece; the high-voltage pre-charging resistor with overload protection further comprises a supporting plate, the fuse is arranged on one side of the supporting plate, the one end of the second foot piece is arranged on the other side of the supporting plate, and the pouring layer is further used for pouring the supporting plate; the foot piece further comprises a third foot piece, one end of the third foot piece being connected with the carbon ceramic resistor and away from the other side of the first foot piece, the pouring layer being further used for pouring the one end of the third foot piece, the other end of the third foot piece being arranged outside the outer shell and electrically connected with external equipment; the other end of the third foot piece is provided with at least one first through slot; the supporting plate is provided with a first through hole and at least one second through hole, one end of the fuse is arranged in the second through hole and connected with the one end of the second foot piece, and the other end of the first foot piece is connected with the other end of the fuse at the first through hole.

2. The high voltage pre-charge resistor with overload protection device of claim 1, wherein, The pouring layer is made of high-temperature-resistant material.

3. The high voltage pre-charge resistor with overload protection device of claim 1, wherein, The second foot piece is provided with two, and the two second foot pieces are arranged on the other side of the supporting plate.

4. The high voltage pre-charge resistor with overload protection device of claim 3, wherein, The other end of the two second foot pieces is provided with a second through slot.

5. The high voltage pre-charge resistor with overload protection device of claim 1, wherein, The material of the fuse is nickel-chromium alloy wire.

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