High-precision direct current shunt

Abstract

The utility model relates to the field of vehicle-mounted diverters, in particular to a high-precision direct-current diverter, which comprises a front loading plate and a rear loading plate, the front loading plate and the rear loading plate are fixedly connected through bolts and nuts, a diverter resistor disc is embedded between the two loading plates, the front end of the diverter resistor disc is connected with a current input block, and the front end of the current input block is connected with a power supply. The rear ends of the diverter resistor discs are connected with current output blocks, temperature sensors are fixedly installed on the diverter resistor discs, the loading plate is of a disc-shaped structure, and the multiple diverter resistor discs are evenly distributed in the circumferential direction of the loading plate. The front end of the loading plate located at the front end is fixedly connected with a heat dissipation fan assembly through bolts, so that a mode of integrally managing the shunts can be adopted, heat dissipation can be carried out on the multiple shunts in a unified mode, management efficiency is improved, and meanwhile labor cost and material cost for installing a heat dissipation system can be saved.

Description

Technical Field

[0001] This utility model relates to the field of vehicle-mounted shunts, specifically a high-precision DC shunt. Background Technology

[0002] The battery management system (BMS) serves as the bridge connecting the battery, a core component of new energy vehicles, to the entire vehicle. Benefiting from the development of new energy vehicles, the BMS, as a core component, has also experienced rapid development. Total current detection is essential, and BMS current detection methods include traditional Hall effect sensor detection and shunt detection.

[0003] Shunt detection methods are widely used in battery management systems due to their high measurement accuracy, relatively low cost, simple measurement method, minimal equipment requirements, and ease of use.

[0004] Its measurement principle is to directly measure the voltage across the shunt, and then, according to Ohm's law, divide the measured voltage by the resistance value of the shunt to obtain the current value in the circuit for current detection.

[0005] As the power consumption of the device increases, the current flowing through the shunt will also increase. The increase in current will cause the temperature of the shunt to rise during the detection process, resulting in temperature drift. That is, the power generated by the shunt itself will increase due to the increase in current, which will affect the resistance value and measurement accuracy of the shunt.

[0006] In modern equipment, multiple heat sinks are often required. Traditional shunt installations typically involve one shunt operating alongside one module. However, many devices require multiple modules with shunts installed. Although the resistance of a shunt is very small, the current flowing through it is often very large, sometimes reaching hundreds or even thousands of amperes. In such cases, the heat generation effect of the shunt is still quite significant. Adding a heat dissipation system to each shunt would increase installation and material costs. Utility Model Content

[0007] To address the shortcomings of existing technologies, the purpose of this utility model is to provide a high-precision DC shunt that adopts an integrated management approach for the shunts. This approach enables unified heat dissipation for multiple shunts, improving management efficiency while saving on labor and material costs associated with installing heat dissipation systems.

[0008] To achieve the above objectives, this utility model provides the following technical solution, including:

[0009] This invention provides a high-precision DC shunt, comprising:

[0010] The loading plate consists of two plates, one in front and one in back, which are fixedly connected by bolts and nuts.

[0011] The shunt resistor is fixedly fitted at both ends of the shunt resistor onto two loading plates;

[0012] A current input block, wherein the current input mechanism is connected to the front end of the shunt resistor;

[0013] A current output block, which is fixedly connected to the rear end of the shunt resistor;

[0014] A temperature sensor, which is fixedly mounted on the shunt resistor plate;

[0015] The loading plate has a disc-shaped structure, and multiple shunt resistors are evenly distributed along the circumference of the loading plate. A cooling fan assembly is fixedly connected to the front end of the loading plate at the front end by bolts.

[0016] Specifically, a heat sink is attached to the shunt resistor, and an annular cavity is formed on the outer side of the loading plate. A heat dissipation pipe is formed in the heat sink, and the front and rear sides of the heat dissipation pipe are respectively connected to the annular cavity in the loading plate on the front and rear sides. A heat dissipation device for removing heat from the heat sink is also connected to the cooling fan assembly.

[0017] Specifically, the heat dissipation device includes a heat dissipation pipe connected in series with the loading plates on the front and rear sides. The loading plates on the front and rear sides are connected in series with the heat dissipation pipe, and the irregularly shaped heat dissipation pipe communicates with the annular cavity. The heat dissipation pipe passes through the front end of the cooling fan assembly, and multiple heat dissipation fins are fixedly installed on the heat dissipation pipe at the front end of the cooling fan assembly.

[0018] Specifically, the heat dissipation device includes a heat dissipation pipe, which is divided into two sections. The cooling fan assembly includes a fixed frame and a fan body. The fixed frame is fixedly mounted on the loading plate located at the front end by bolts. The edge of the fan body is annular and rotatably connected to the fixed frame. A fluid exchange chamber is provided inside the fixed frame. A fluid passage chamber is machined in the middle of the fan body. The fan blades and edges of the fan body are machined into a hollow shape to allow the fluid passage chamber and the fluid exchange chamber to communicate. A heat dissipation pipe is rotatably connected to the front of the fluid passage chamber. The heat dissipation pipe communicates with the annular cavity in the loading plate at the rear. The fluid exchange chamber in the fixed frame communicates with the annular cavity in the loading plate at the front through another heat dissipation pipe.

[0019] Specifically, the heat dissipation pipes have a multi-layered reciprocating structure.

[0020] Specifically, the current input block is fixedly mounted on the shunt resistor by bolts. The shunt resistor is made of manganese copper and has a flat design.

[0021] Specifically, both the current input block and the current output block are made of brass.

[0022] Specifically, through slots are formed on the shunt resistor sheet.

[0023] Specifically, the current input block is slidably connected to the shunt resistor plate, and a resistance compensation system is also provided on the loading plate. The resistance compensation system includes an adjusting screw, which is rotatably mounted between the front and rear loading plates. An angle measuring sensor coaxial with the adjusting screw and used to measure the rotation angle of the adjusting screw is fixedly installed on one of the loading plates. The current input block is slidably sleeved on the shunt resistor plate, and the adjusting screw is threadedly connected to the current input block.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) By concentrating the shunt resistors into a disc-shaped loading plate, all the shunt resistors can be cooled by a single cooling fan assembly, which meets the requirements of integrated management and greatly reduces installation and material costs.

[0026] (2) In this invention, when the liquid flows through the heat dissipation pipe in the heat sink, it absorbs the heat emitted by the shunt resistor and enters the liquid exchange chamber through the annular cavity and heat dissipation pipe. Then, it flows through the liquid passage body and fan blades into the liquid exchange chamber. During this process, the fan can increase the heat dissipation area and the air flow speed on the fan surface is faster, thereby further improving the heat dissipation efficiency.

[0027] (3) The present invention controls the rotation of the adjusting screw through a servo drive system such as a servo motor, thereby controlling the movement of the current input block. The angle of the adjusting screw is measured by an angle measuring sensor until the adjusting screw rotates to the desired angle. This can correct the measurement error caused by the change in the resistance of the shunt resistor when the temperature rises, thereby improving the current detection capability of the shunt. Attached Figure Description

[0028] Figure 1 A schematic diagram of the structure of a DC shunt provided by this utility model;

[0029] Figure 2 A schematic diagram of the structure of a shunt resistor element provided by this utility model;

[0030] Figure 3 A schematic diagram of the structure of the second type of DC shunt provided by this utility model;

[0031] Figure 4A schematic diagram of the structure of the third type of DC shunt provided by this utility model;

[0032] Figure 5 This is a schematic diagram showing the connection between the heat dissipation pipe and the annular cavity in this utility model;

[0033] Figure 6 In this utility model Figure 5 Enlarged view of a portion of point A in the middle;

[0034] Figure 7 This is a schematic diagram of the internal structure of a shunt resistor element according to the present invention;

[0035] Figure 8 This is a schematic diagram showing the installation location of the resistance compensation system in this utility model;

[0036] Figure 9 In this utility model Figure 8 A magnified view of a portion of point B in the middle.

[0037] 1. Loading plate; 11. Annular cavity; 2. Shunt resistor; 21. Heat sink; 211. Heat dissipation pipe; 3. Current input block; 4. Current output block; 5. Temperature sensor; 6. Cooling fan assembly; 61. Fixing frame; 611. Fluid exchange chamber; 62. Fan body; 621. Fluid passage chamber; 7. Heat dissipation device; 71. Heat dissipation pipe; 72. Heat dissipation fins; 8. Resistance compensation system; 81. Adjusting screw; 82. Angle measurement sensor. Detailed Implementation

[0038] The following description is intended to disclose the present invention so that those skilled in the art can implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art.

[0039] Reference Figures 1 to 9 The present invention provides a further description of a high-precision DC shunt.

[0040] like Figure 1 As shown, this utility model provides a high-precision DC shunt, comprising:

[0041] Loading plate 1, wherein there are two loading plates 1, one in front and one in back, and the two loading plates 1 are fixedly connected by bolts and nuts;

[0042] Shunt resistor 2, the front and rear ends of the shunt resistor 2 are fixedly fitted onto two loading plates 1;

[0043] Current input block 3, which is connected to the front end of shunt resistor 2;

[0044] Current output block 4, which is fixedly connected to the rear end of the shunt resistor 2;

[0045] Temperature sensor 5, which is fixedly mounted on the shunt resistor 2;

[0046] The loading plate 1 has a disc-shaped structure. Multiple shunt resistors 2 are evenly distributed along the circumference of the loading plate 1. A cooling fan assembly 6 is fixedly connected to the front end of the loading plate 1 at the front end by bolts.

[0047] It should be noted that during operation, current enters the shunt resistor 2 through the current input block 3. The temperature sensor 5 monitors the temperature of the shunt resistor 2 in real time and controls the fan speed in the cooling fan assembly 6 through a related control system. This keeps the temperature of the shunt resistor 2 within a range that allows its resistance value to remain relatively stable, thus making the measured current more accurate. In various modern devices, multiple shunt resistors 2 are often required. Traditionally, one shunt is installed alongside one module, but many devices require multiple modules with shunts installed. Although the resistance of the shunt is very small, through… The current in these circuits is often very large, sometimes reaching hundreds or even thousands of amperes. Under such conditions, the heating effect of the shunt is still quite significant. The shunt will experience temperature drift at high temperatures, and the electrical components and wires connected to it, as well as the shunt itself, are more prone to damage and aging. However, if each shunt resistor 2 is equipped with a separate heat dissipation system, it will increase the installation and material costs. By concentrating the shunt resistor 2 into a disc-shaped mounting plate 1, only one cooling fan assembly 6 is needed to dissipate heat from all the shunt resistor 2, which not only meets the requirements of integrated management but also greatly reduces the installation and material costs.

[0048] like Figures 3 to 7 As shown, a heat sink 21 is attached to the shunt resistor 2. An annular cavity 11 is provided on the outer side of the loading plate 1. A heat dissipation pipe 211 is provided in the heat sink 21. The front and rear sides of the heat dissipation pipe 211 are respectively connected to the annular cavity 11 in the loading plate 1 on the front and rear sides. A heat dissipation device 7 for removing heat from the heat sink 21 is also connected to the cooling fan assembly 6.

[0049] It should be noted that by the liquid flowing back and forth in the annular cavity 11, the heat dissipation pipe 211 in the heat sink 21 and the heat dissipation device 7, the liquid absorbs the heat of the shunt resistor 2 when it flows through the heat dissipation pipe 211, and dissipates heat at the front end of the cooling fan when the liquid flows through the heat dissipation pipe 71. In this way, the efficiency of heat dissipation can be better improved by using both air flow heat dissipation and liquid flow heat dissipation. At the same time, the cooling fan can further assist the liquid in heat dissipation.

[0050] like Figure 3 , Figures 5 to 7 As shown, the heat dissipation device 7 includes a heat dissipation pipe 71, which is connected in series with the loading plates 1 on the front and rear sides. The heat dissipation pipe 71 is connected in series on the loading plates 1 on the front and rear sides, and the heat dissipation pipe 71 communicates with the annular cavity 11. The irregular heat dissipation pipe 71 passes through the front end of the cooling fan assembly 6, and multiple heat dissipation fins 72 are fixedly installed on the heat dissipation pipe 71 at the front end of the cooling fan assembly 6.

[0051] A pump for driving the cooling liquid can be connected in series on the heat pipe. When the cooling liquid flows through the cooling fins 72 in the heat pipe 71 of the heat dissipation device 7, the cooling fins 72 can increase the heat dissipation area, thereby further improving the heat dissipation efficiency.

[0052] like Figures 4 to 7 As shown, the heat dissipation device 7 includes a heat dissipation pipe 71, which is divided into two sections. The cooling fan assembly 6 includes a fixing frame 61 and a fan body 62. The fixing frame 61 is fixedly mounted on the loading plate 1 located at the front end by bolts. The edge of the fan body 62 is annular and rotatably connected to the fixing frame 61. A fluid exchange chamber 611 is provided in the fixing frame 61. A fluid passage chamber 621 is machined in the middle of the fan body 62. The fan blades and edges of the fan body 62 are machined into a hollow shape so that the fluid passage chamber 621 and the fluid exchange chamber 611 communicate. A heat dissipation pipe 71 is rotatably connected to the front of the fluid passage chamber 621. The heat dissipation pipe 71 communicates with the annular cavity 11 in the loading plate 1 at the rear. The fluid exchange chamber 611 in the fixing frame 61 communicates with the annular cavity 11 in the loading plate 1 at the front through another heat dissipation pipe 71.

[0053] During the heat dissipation process of the heat dissipation device 7, when the liquid flows through the heat dissipation pipe 211 in the heat sink 21, it absorbs the heat emitted by the shunt resistor 2 and enters the liquid exchange chamber 611 through the annular cavity 11 and the heat dissipation pipe 71. Then, it flows through the liquid passage 621 and the fan blades into the liquid exchange chamber 611. During this process, the fan can increase the heat dissipation area and the air flow speed on the fan surface is faster, thereby further improving the heat dissipation efficiency.

[0054] like Figure 7As shown, the heat dissipation pipe 211 has a multi-layer reciprocating structure.

[0055] This design effectively increases the contact area for heat absorption, thereby enhancing the temperature control capability of the shunt resistor 2.

[0056] The shunt resistor 2 is made of manganese copper and has a flat design.

[0057] Manganese copper material can ensure both the ability to carry current and good heat conduction and dissipation.

[0058] Both the current input block 3 and the current output block 4 are made of brass.

[0059] Using brass, which has strong thermal and electrical conductivity, as the medium for conducting current and heat can increase the thermal conductivity of the shunt.

[0060] like Figure 2 As shown, a through slot is formed on the shunt resistor 2.

[0061] This allows for a greater amount of air to flow through the shunt resistor 2, thereby improving heat dissipation efficiency.

[0062] like Figure 8 and Figure 9 As shown, the current input block 3 is slidably connected to the shunt resistor 2. A resistance compensation system 8 is also provided on the loading plate 1. The resistance compensation system 8 includes an adjusting screw 81, which is rotatably mounted between the front and rear loading plates 1. An angle measuring sensor 82, coaxial with the adjusting screw 81, is fixedly installed on one of the loading plates 1 to measure the rotation angle of the adjusting screw 81. The current input block 3 is slidably sleeved on the shunt resistor 2, and the adjusting screw 81 is threadedly connected to the current input block 3.

[0063] During operation, temperature sensor 5 measures the temperature of shunt resistor 2 and transmits this value to resistance compensation system 8. Resistance compensation system 8 stores the resistance values ​​of shunt resistor 2 at different temperatures. It then uses the temperature reading from temperature sensor 5 to determine the current resistance value of shunt resistor 2. The resistance value of shunt resistor 2 is directly proportional to its length. By adjusting the position of current input block 3, resistance compensation system 8 changes the length of shunt resistor 2 connected to the circuit, ensuring its resistance remains constant and improving the shunt's current detection capability. After determining the resistance value, resistance compensation system 8 compares the current resistance value with the original resistance value (e.g., at a specific temperature), taking the inverse proportional result and using it as the reference value. The product of the initial lengths reveals the required length of the shunt resistor 2 in the circuit to maintain its resistance. The difference between this length and the original length of the shunt resistor 2 is the distance the current input block 3 needs to be adjusted. During the adjustment of the current input block 3, a servo drive system, such as a servo motor, controls the rotation of the adjusting screw 81, thereby controlling the movement of the current input block 3. The difference is compared with the pitch of the adjusting screw 81 to determine the number of rotations required and the required angle. An angle sensor 82 measures the angle of the adjusting screw 81. After the adjusting screw 81 reaches the desired angle, the resistance compensation system 8 stops the servo motor from rotating the adjusting screw 81. This technical solution corrects measurement errors caused by changes in the resistance of the shunt resistor 2 due to temperature increases, thereby improving the shunt's current detection capability and measurement accuracy.

[0064] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0065] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0066] The above description is merely a preferred embodiment of this utility model. The protection scope of this utility model is not limited to the above embodiments. All technical solutions falling within the scope of this utility model's concept are protected. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of this utility model should also be considered within the protection scope of this utility model.

Claims

1. A high-precision DC shunt, characterized in that, include: Loading plate (1), the loading plate (1) consists of two plates, front and back, which are fixedly connected by bolts and nuts; The shunt resistor (2) is fixedly fitted at both ends of the shunt resistor (2) onto two loading plates (1); Current input block (3), which is connected to the front end of the shunt resistor (2); Current output block (4), which is fixedly connected to the rear end of the shunt resistor (2); Temperature sensor (5), the temperature sensor (5) is fixedly mounted on the shunt resistor (2); The loading plate (1) has a disc-shaped structure. Multiple shunt resistors (2) are evenly distributed along the circumference of the loading plate (1). A cooling fan assembly (6) is fixedly connected to the front end of the loading plate (1) by bolts.

2. The high-precision DC shunt according to claim 1, characterized in that, A heat sink (21) is attached to the shunt resistor (2). An annular cavity (11) is provided on the outer side of the loading plate (1). A heat dissipation pipe (211) is provided in the heat sink (21). The front and rear sides of the heat dissipation pipe (211) are respectively connected to the annular cavity (11) in the loading plate (1) on the front and rear sides. A heat dissipation device (7) for removing heat from the heat sink (21) is also connected to the cooling fan assembly (6).

3. A high-precision DC shunt according to claim 2, characterized in that, The heat dissipation device (7) includes a heat dissipation pipe (71), which is connected in series with the loading plates (1) on the front and rear sides. The loading plates (1) on the front and rear sides are connected in series with the heat dissipation pipe (71), and the heat dissipation pipe (71) communicates with the annular cavity (11). The heat dissipation pipe (71) passes through the front end of the cooling fan assembly (6), and multiple heat dissipation fins (72) are fixedly installed on the heat dissipation pipe (71) at the front end of the cooling fan assembly (6).

4. A high-precision DC shunt according to claim 2, characterized in that, The heat dissipation device (7) includes a heat dissipation pipe (71), which is divided into two sections. The cooling fan assembly (6) includes a fixing frame (61) and a fan body (62). The fixing frame (61) is fixedly mounted on the loading plate (1) located at the front end by bolts. The edge of the fan body (62) is annular and rotatably connected to the fixing frame (61). A fluid exchange chamber (611) is provided inside the fixing frame (61). A through-hole is machined in the middle of the fan body (62). The liquid cavity (621) is made of hollowed-out fan blades and edges of the fan body (62) so that the liquid passage cavity (621) and the liquid exchange cavity (611) are connected. A heat dissipation pipe (71) is rotatably connected to the front of the liquid passage cavity (621). The heat dissipation pipe (71) is connected to the annular cavity (11) in the loading plate (1) behind. The liquid exchange cavity (611) in the fixed frame (61) is connected to the annular cavity (11) in the loading plate (1) in front through another heat dissipation pipe (71).

5. The high-precision DC shunt according to any one of claims 2, 3, or 4, characterized in that, The heat dissipation pipe (211) has a multi-layer reciprocating structure.

6. A high-precision DC shunt according to claim 1, characterized in that, The current input block (3) is fixedly mounted on the shunt resistor (2) by bolts. The shunt resistor (2) is made of manganese copper and has a flat design.

7. A high-precision DC shunt according to claim 1 or 6, characterized in that, Both the current input block (3) and the current output block (4) are made of brass.

8. A high-precision DC shunt according to claim 6, characterized in that, A through slot is formed on the shunt resistor sheet (2).

9. A high-precision DC shunt according to claim 1, characterized in that, The current input block (3) is slidably connected to the shunt resistor (2). A resistance compensation system (8) is also provided on the loading plate (1). The resistance compensation system (8) includes an adjusting screw (81). The adjusting screw (81) is rotatably mounted between the front and rear loading plates (1). An angle measuring sensor (82) coaxial with the adjusting screw (81) and used to measure the rotation angle of the adjusting screw (81) is fixedly installed on one of the loading plates (1). The current input block (3) is slidably sleeved on the shunt resistor (2). The adjusting screw (81) is threadedly connected to the current input block (3).

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