High-precision direct current shunt

Abstract

The invention 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 fixedly embedded between the front loading plate and the rear loading plate, and the front end of the diverter resistor disc is connected with a current input mechanism. The rear end of the diverter resistor disc is fixedly connected with the current output block, a temperature sensor is further installed on the diverter resistor disc, and a resistance compensation system used for being combined with a voltage measuring device to accurately measure the current value on the diverter resistor disc is further provided, so that the temperature of the surface of the diverter resistor disc can be collected, and the temperature of the surface of the diverter resistor disc can be accurately measured. Measurement errors caused by temperature changes of the diverter are corrected through a related system, so that the current detection capability of the diverter is improved, and the measurement precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle shunts, and more specifically to a high-precision DC shunt. Background Art

[0002] The battery management system is a bridge connecting the core component battery of new energy vehicles and the whole vehicle. Benefiting from the development of new energy vehicles, the battery management system as a core component has also developed rapidly. Among them, the total current detection is essential. The current detection of the battery management system is divided into the traditional Hall sensor detection method and the shunt detection method.

[0003] The shunt detection method is applied to the battery management system due to its high measurement accuracy, relatively low cost, simple measurement method, few used devices, and convenience and quickness.

[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] With the increase in device power consumption, the current flowing through the shunt will also increase. The increase in the current value will cause the temperature of the shunt to rise during the detection process, resulting in the phenomenon of temperature drift, that is, the power generated by the shunt itself will increase due to the increase in current, affecting the resistance value and measurement accuracy of the shunt.

[0006] Traditional shunts often only have the function of voltage acquisition and cannot be adjusted due to the change in the resistance value of the shunt when the temperature changes. Therefore, during use, the measured current value is likely to deviate due to the increase in the shunt temperature. Summary of the Invention

[0007] In order to overcome the above technical problems, the present invention provides a high-precision DC shunt, which can collect the temperature on the surface of the shunt resistance chip, correct the measurement error caused by the change in the shunt temperature through a related system, thereby improving the current detection ability of the shunt and the measurement accuracy.

[0008] The purpose of the present invention can be achieved through the following technical solutions:

[0009] Based on this, the present invention provides a high-precision DC shunt, including:

[0010] Loading plates, there are two loading plates in the front and back, and the two loading plates in the front and back are fixedly connected by bolts and nuts;

[0011] A shunt resistance chip, the front and rear ends of the shunt resistance chip are fixedly fitted on the two loading plates;

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

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

[0014] A temperature sensor, which is fixedly installed on the shunt resistor sheet;

[0015] A resistance compensation system, which is used to accurately measure the current value on the shunt resistor sheet in combination with a voltage measuring device.

[0016] Specifically, the resistance compensation system receives the temperature value Ta provided by the temperature sensor, stores the resistance value Ra of the shunt resistor sheet at different temperatures in the resistance compensation system, and receives the voltage value Ua between the current input mechanism and the current output block measured by the voltage measuring device. Finally, the current value Ia passing through the shunt resistor sheet is measured by the ratio of the voltage value Ua to the resistance value Ra, that is, Ia = Ua / Ra.

[0017] Specifically, the resistance compensation system includes an adjusting screw A, which is rotatably installed between two front and rear loading plates. An angle measuring sensor A coaxial with the adjusting screw A is fixedly installed on one of the loading plates to measure the rotation angle of the adjusting screw A. The current input mechanism includes a current input block, which is slidably sleeved on the shunt resistor sheet, and the adjusting screw A is threadedly connected to the current input block.

[0018] Specifically, the shunt resistor sheet is composed of two overlapping sheets. The current input mechanism includes a support rod corresponding to the position of the shunt resistor sheet. A contact piece is arranged between the two shunt resistor sheets. The contact piece is slidably installed on the support rod. An insurance motor is fixedly installed on the support rod. The output shaft of the insurance motor is processed into a threaded shape, and the output shaft of the insurance motor is threadedly connected to the contact piece. The positive and negative poles of the insurance motor are respectively connected to the middle position of the contact piece and the current output block through wires.

[0019] Specifically, the support rod is slidably installed between two front and rear loading plates in the front-rear direction. The resistance compensation system includes an adjusting screw B, which is rotatably installed between two front and rear loading plates. An angle measuring sensor B coaxial with the adjusting screw B is fixedly installed on one of the loading plates to measure the rotation angle of the adjusting screw B, and the adjusting screw B is threadedly connected to the support rod.

[0020] Specifically, the contact piece includes a contact fixing piece and a contact elastic piece. The contact fixing piece is slidably mounted on the support rod and is threadedly connected to the output shaft of the insurance motor. At both ends of the contact fixing piece facing the shunt resistor piece, a contact elastic piece is slidably connected respectively, and a spring with both ends fixedly connected to the two contact elastic pieces is arranged between the two contact elastic pieces.

[0021] The current input mechanism includes a current input block. The current input block is fixedly installed at the front end of the shunt resistor piece. There are two shunt resistor pieces. One of the shunt resistor pieces is slidably connected to the loading plate, and the other shunt resistor piece is fixedly connected to the loading plate. An insurance motor is fixedly connected to the loading plate in the front. The output end of the insurance motor is threadedly connected to the movable current input block.

[0022] Specifically, the loading plate is of a disc-shaped structure. A plurality of shunt plates are evenly distributed along the circumference of the loading plate. A heat dissipation fan assembly is fixedly connected to the front end of the loading plate at the front end through bolts.

[0023] Specifically, a heat sink is attached to the shunt resistor piece. Annular grooves are formed on the outer sides of the loading plates. Heat dissipation pipelines are formed in the heat sink, and the front and rear sides of the heat dissipation pipelines are respectively communicated with the annular grooves in the front and rear loading plates. An irregular heat dissipation pipe is connected in series on the front and rear loading plates, and the irregular heat dissipation pipe is communicated with the annular groove. The irregular heat dissipation pipe passes through the front end of the heat dissipation fan assembly.

[0024] Specifically, a plurality of heat dissipation fins are fixedly installed at the position where the irregular heat dissipation pipe is located at the front end of the heat dissipation fan assembly.

[0025] Specifically, the heat dissipation pipeline is of a multi-layer reciprocating structure.

[0026] Advantages of the present invention:

[0027] 1. The present invention measures the temperature value Ta of the shunt resistor piece through a temperature sensor and uploads the temperature value Ta to the resistance compensation system. At this time, the resistance compensation system stores the resistance values of the shunt resistor piece at different temperature values in its system. The resistance compensation system will compare Ta with the temperature values stored in the system one by one, find the resistance value Ra corresponding to the value closest to it, and then determine the current value Ia in the shunt resistor piece through Ohm's law. Through the above technical solution, the measurement error caused by the change of the resistance value of the shunt resistor piece itself when the temperature rises can be corrected, thereby improving the current detection ability of the shunt and improving the measurement accuracy.

[0028] 2. When a shunt resistor chip in the present invention fails and opens the circuit, the fuse motor will obtain sufficient voltage to drive its rotation. At this time, the output shaft of the fuse motor is threadedly connected to the contact piece, causing the contact piece to slide on the support rod until the contact piece contacts another shunt resistor chip. At this time, the fuse motor will be in an open circuit state again, and the circuit will be reconnected, providing a shunt circuit fuse system without the intervention of any control system.

[0029] 3. By concentrating the shunt resistor chips in a disc-shaped loading plate in the present invention, all the shunt resistor chips can be cooled by only one cooling fan, which not only meets the requirements of integrated management but also can greatly reduce the installation cost and material cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be further described below with reference to the accompanying drawings.

[0031] Figure 1 is the overall structural schematic diagram of the present invention;

[0032] Figure 2 is the schematic diagram of another perspective of the overall structure in the present invention;

[0033] Figure 3 is the present invention Figure 2 the partial enlarged structural schematic diagram at A in;

[0034] Figure 4 is the overall structural schematic diagram of the second embodiment in the present invention;

[0035] Figure 5 is the structural schematic diagram of another perspective of the overall structure of the second embodiment in the present invention;

[0036] Figure 6 is the structural schematic diagram of the contact piece in the present invention;

[0037] Figure 7 is the connection schematic diagram of the special-shaped heat dissipation pipe, the annular groove and the heat dissipation fins in the present invention;

[0038] Figure 8 is the present invention Figure 7 the partial enlarged structural schematic diagram at B in;

[0039] Figure 9 is the structural schematic diagram of the heat dissipation fins in the present invention;

[0040] Figure 10 is the structural schematic diagram of the third embodiment in the present invention.

[0041] In the figure: 1. Loading plate; 11. Annular groove; 2. Shunt resistor chip; 21. Heat sink; 211. Heat dissipation pipeline; 3. Current input mechanism; 31. Current input block; 32. Support rod; 33. Contact piece; 331. Contact fixing piece; 332. Contact elastic piece; 333. Spring; 34. Insurance motor; 4. Current output block; 5. Temperature sensor; 6. Resistance compensation system; 61. Adjusting screw A; 62. Angle measurement sensor A; 63. Adjusting screw B; 64. Angle measurement sensor B; 7. Cooling fan; 8. Special-shaped heat dissipation pipe; 81. Heat dissipation fin. Detailed implementation mode

[0042] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative work shall fall within the protection scope of the present invention.

[0043] To solve the technical problems proposed in the present invention;

[0044] Embodiment 1:

[0045] As Figure 1 and Figure 2 shown, the present invention provides a high-precision DC shunt, including:

[0046] Loading plates 1, there are two loading plates 1 in the front and back, and the two loading plates 1 in the front and back are fixedly connected by bolts and nuts;

[0047] Shunt resistor chip 2, the front and rear ends of the shunt resistor chip 2 are fixedly fitted on the two loading plates 1;

[0048] Current input mechanism 3, the current input mechanism 3 is connected to the front end of the shunt resistor chip 2;

[0049] Current output block 4, the current output block 4 is fixedly connected to the rear end of the shunt resistor chip 2;

[0050] Temperature sensor 5, the temperature sensor 5 is fixedly installed on the shunt resistor chip 2;

[0051] Resistance compensation system 6, the resistance compensation system 6 is used to accurately measure the current value on the shunt resistor chip 2 in combination with a voltage measuring device.

[0052] The resistor compensation system 6 receives the temperature value Ta provided by the temperature sensor 5, stores the resistance value Ra of the shunt resistor chip 2 at different temperatures in the resistor compensation system 6, and receives the voltage value Ua between the current input mechanism 3 and the current output block 4 measured by the voltage measuring device. Finally, the current value Ia passing through the shunt resistor chip 2 is determined by the ratio of the voltage value Ua to the resistance value Ra, that is, Ia = Ua / Ra.

[0053] During use, the current input mechanism 3 and the current output block 4 are respectively connected to the positive and negative poles of the power supply. During use, the current is input into the shunt resistor chip 2 through the current input mechanism 3 and output through the current output block 4. The voltage measuring device in the device is respectively connected to the current input mechanism 3 and the current output block 4 to measure the voltage difference across the shunt resistor chip 2. The resistor compensation system 6 determines the current value flowing through the shunt resistor chip 2 according to Ohm's law based on the voltage difference and the resistance value of the shunt resistor chip 2 itself. During this process, the temperature sensor 5 measures the temperature value Ta of the shunt resistor chip 2 and uploads the temperature value Ta to the resistor compensation system 6. At this time, the resistor compensation system 6 stores the resistance values of the shunt resistor chip 2 at different temperature values in its system. The resistor compensation system 6 compares Ta with the temperature values stored in the system one by one to find the resistance value Ra corresponding to the value closest to it, and then determines the current value Ia passing through the shunt resistor chip 2 through Ohm's law. Through the above technical solution, the measurement error caused by the change in the resistance value of the shunt resistor chip 2 itself when the temperature rises can be corrected, thereby improving the current detection ability of the shunt and further improving the measurement accuracy.

[0054] As Figure 1 、 Figure 2 and Figure 3 shown, the resistor compensation system 6 includes an adjusting screw A61. The adjusting screw A61 is rotatably mounted between the front and rear mounting plates 1. An angle measuring sensor A62 coaxial with the adjusting screw A61 for measuring the rotation angle of the adjusting screw A61 is fixedly installed on one of the mounting plates 1. The current input mechanism 3 includes a current input block 31. The current input block 31 is slidably sleeved on the shunt resistor chip 2. The adjusting screw A61 is threadedly connected to the current input block 31.

[0055] During the measurement process, the temperature sensor 5 measures the temperature value of the shunt resistor chip 2 and transmits the temperature value of the shunt resistor chip 2 to the resistance compensation system 6. The resistance compensation system 6 stores the resistance values of the shunt resistor chip 2 at different temperature values in its system. The resistance compensation system 6 will look up the resistance value of the shunt resistor chip 2 at this time according to the temperature value of the shunt resistor chip 2 on the temperature sensor 5. The resistance value of the shunt resistor chip 2 is directly proportional to the length of the shunt resistor chip 2. At this time, the resistance compensation system 6 adjusts the position of the current input block 31, thereby changing the length of the shunt resistor chip 2 connected to the circuit, and further ensuring that the resistance value of the shunt resistor chip 2 in the circuit remains unchanged, thereby improving the current detection ability of the shunt. During this process, after the resistance compensation system 6 obtains the resistance value of the shunt resistor chip 2, it will compare the resistance value of the shunt resistor chip 2 during operation with the original resistance value according to the original resistance value of the shunt resistor chip 2, for example, the resistance value of the shunt resistor chip 2 at 25 degrees Celsius. Taking the product of the inverse ratio result and the original length of the shunt resistor chip 2 can obtain the length that the shunt resistor chip 2 needs to be connected to the circuit to keep its resistance value in the circuit unchanged. The difference between this length and the original length of the shunt resistor chip 2 is the distance that the current input block 31 needs to be adjusted. During the process of adjusting the distance of the current input block 31, the rotation of the adjusting screw A61 is controlled by a servo drive system such as a servo motor, thereby controlling the movement of the current input block 31. During this process, by comparing the above difference with the pitch of the adjusting screw A61, the number of turns of the rotation of the adjusting screw A61 is obtained, and then the angle that the adjusting screw A61 needs to rotate is obtained. During this process, the angle measuring sensor A62 measures the angle of rotation of the adjusting screw A61. After the adjusting screw A61 rotates to the required angle, the resistance compensation system 6 will control the servo motor to stop driving the rotation of the adjusting screw A61.

[0056] Embodiment 2:

[0057] As Figure 4 and Figure 5 shown, the shunt resistor chip 2 is two overlapping pieces. The current input mechanism 3 includes a support rod 32. The position of the support rod 32 corresponds to that of the shunt resistor chip 2. A contact piece 33 is arranged between the two shunt resistor chips 2. The contact piece 33 is slidably mounted on the support rod 32. An insurance motor 34 is fixedly installed on the mounting rod. The output shaft of the insurance motor 34 is processed into a threaded shape. The output shaft of the insurance motor 34 is threadedly connected to the contact piece 33. The positive and negative poles of the insurance motor 34 are respectively connected to the middle position of the contact piece 33 and the current output block 4 through wires.

[0058] In a traditional device, during the connection process of the shunt, if a fault occurs in the circuit where the shunt resistor chip 2 is located or there is looseness at the wiring point, etc., the circuit will show an open circuit phenomenon, which will cause a greater impact in some cases. For example, if the above situation occurs during the vehicle's driving on the highway, it is likely to lead to an accident. In the present invention, under normal circumstances, the positive and negative poles of the insurance motor 34 are respectively connected to the contact piece 33 and the current output block 4. The insurance motor 34 is connected in parallel with the shunt resistor chip 2. Since the resistance value of the shunt resistor chip 2 is very small, the voltage difference across the shunt resistor chip 2 is very small. At this time, the insurance motor 34 is in a nearly open circuit state. However, when the shunt resistor chip 2 fails and an open circuit occurs, at this time, the insurance motor 34 will obtain sufficient voltage to drive its rotation. At this time, the output shaft of the insurance motor 34 is threadedly connected to the contact piece 33, causing the contact piece 33 to slide on the support rod 32 until the contact piece 33 contacts another shunt resistor chip 2. At this time, the insurance motor 34 will be in an open circuit state again, and at this time, the circuit is reconnected. The above technical solution completely relies on the most basic electrical and mechanical principles and provides a shunt circuit insurance system without the intervention of any control system, belonging to a passive solution, thus reliably providing a layer of protection for the safety of the circuit.

[0059] As Figure 4 and Figure 5 shown, the support rod 32 is slidably mounted in the front-rear direction between two loading plates 1. The resistance compensation system 6 includes an adjusting screw B63, and the adjusting screw B63 is rotatably mounted at a position between the front and rear loading plates 1. An angle measuring sensor B64 coaxial with the adjusting screw B63 and used for measuring the rotation angle of the adjusting screw B63 is fixedly installed on one of the loading plates 1. The adjusting screw B63 is threadedly connected to the support rod 32.

[0060] During use, the temperature sensor 5 measures the temperature value of the shunt resistor chip 2. The resistance compensation system 6 stores the resistance values of the shunt resistor chip 2 at different temperature values in its system. The resistance compensation system 6 will find the resistance value of the shunt resistor chip 2 at this time according to the temperature value of the shunt resistor chip 2 on the temperature sensor 5. At this time, the position of the support rod 32 is adjusted through the resistance compensation system 6, so as to change the length of the shunt resistor chip 2 connected to the circuit, and then ensure that the resistance value of the shunt resistor chip 2 in the circuit remains unchanged, and further improve the current detection ability of the shunt. During this process, the rotation of the adjusting screw B63 is driven by the servo drive system, and the rotation angle is determined according to the ratio between the distance to be adjusted and the pitch of the adjusting screw B63, and the rotation angle of the adjusting screw B63 is detected by the angle measurement sensor B64. Finally, the resistance compensation system 6 will control the adjusting screw B63 through the control servo system to make the support rod 32 and the contact piece 33 reach the required position. Through the above technical solution, while ensuring that the circuit can be insured, the length of the shunt resistor chip 2 connected to the circuit can still be adjusted to ensure that the resistance value of the shunt resistor chip 2 connected to the circuit changes.

[0061] As Figure 5 and Figure 6 shown, the contact piece 33 includes a contact fixing piece 331 and a contact elastic piece 332. The contact fixing piece 331 is slidably mounted on the support rod 32 and is threadedly connected to the output shaft of the insurance motor 34. One contact elastic piece 332 is slidably connected to each end of the contact fixing piece 331 facing the shunt resistor chip 2, and a spring 333 with both ends fixedly connected to the two contact elastic pieces 332 is arranged between the two contact elastic pieces 332.

[0062] It should be noted that through the above technical solution, the contact piece 33 will maintain a better contact state during the contact with the shunt resistor chip 2, thus ensuring a better electric conduction effect.

[0063] Embodiment Three:

[0064] As Figure 10 shown, the current input mechanism 3 includes a current input block 31. The current input block 31 is fixedly installed at the front end of the shunt resistor chip 2. There are two shunt resistor chips 2. One of the shunt resistor chips 2 is slidably connected to the loading plate 1, and the other shunt resistor chip 2 is fixedly connected to the loading plate 1. An insurance motor 34 is fixedly connected to the front loading plate 1. The output end of the insurance motor 34 is threadedly connected to the movable current input block 31. The positive and negative poles of the insurance motor 34 are respectively connected to the current input block 31 and the current output block 4 through wires.

[0065] In this way, if a fault occurs in the circuit where the shunt resistor chip 2 is located or there is looseness at the wiring connection, etc., the fuse motor 34 will rotate to drive the movable current input block 31, the shunt resistor chip 2, and the current output block 4 to approach the non-movable shunt resistor chip 2 until the movable current input block 31 and the current output block 4 are in contact with the non-movable current input block 31 and the current output block 4. In this way, a fuse system is also completed. The advantage of this is that the contact area of the current input will be larger and the current that can be carried will be stronger.

[0066] Embodiment 4:

[0067] As Figure 1 shown, the loading plate 1 is of a disc-shaped structure, and a plurality of shunt plates are evenly distributed along the circumference of the loading plate 1. A heat dissipation fan 7 assembly is fixedly connected to the front end of the loading plate 1 at the front end by bolts.

[0068] It should be noted that in various current devices, the presence of multiple shunt resistor chips 2 is often required. The traditional installation method of shunt resistors is often that one shunt resistor operates following one module, and many devices often require multiple modules for installing shunt resistors. And although the resistance value of the shunt resistor is very small, the current passing through it is often very large in many cases, often several hundred amperes or even several thousand amperes. In this case, the heat generation effect of the shunt resistor is still relatively obvious. The shunt resistor will generate temperature drift at high temperatures, and the electrical components, wires, and itself connected to it are more likely to be damaged and aged. However, if a heat dissipation system is installed separately for each shunt resistor chip 2, it will increase the installation cost and material cost. Therefore, by concentrating the shunt resistor chips 2 in the disc-shaped loading plate 1, only one heat dissipation fan 7 is needed to dissipate heat for all the shunt resistor chips 2, which not only meets the requirements of integrated management but also can greatly reduce the installation cost and material cost.

[0069] As Figure 1 、 Figure 2 、 Figure 7 、 Figure 8 and Figure 9 shown, a heat sink 21 is attached to the shunt resistor chip 2. Annular grooves 11 are opened on the outer sides in the loading plate 1. Heat dissipation pipelines 211 are opened in the heat sink 21, and the front and rear sides of the heat dissipation pipelines 211 are respectively communicated with the annular grooves 11 in the front and rear loading plates 1. An irregular heat dissipation pipe 8 is connected in series on the front and rear loading plates 1, and the irregular heat dissipation pipe 8 is communicated with the annular groove 11. The irregular heat dissipation pipe 8 passes through the front end of the heat dissipation fan 7 assembly.

[0070] By connecting a driving pump in series on the special-shaped heat dissipation pipe 8, adding heat dissipation liquid to the annular groove 11, the heat dissipation pipeline 211 and the special-shaped heat dissipation pipe 8, and driving the flow of the liquid by the driving pump, the heat dissipation liquid will absorb the heat of the shunt resistor chip 2 when flowing through the heat dissipation pipeline 211, and dissipate heat when the heat dissipation liquid flows through the position in front of the heat dissipation fan 7 after passing through the special-shaped heat dissipation pipe 8. In this way, the heat dissipation efficiency is further improved.

[0071] As Figure 1 shown, a plurality of heat dissipation fins 81 are fixedly installed at the position of the front end of the special-shaped heat dissipation pipe 8 in the heat dissipation fan 7 assembly.

[0072] In this way, the heat dissipation area will be greatly increased and the heat dissipation speed will be improved.

[0073] As Figure 9 shown, the heat dissipation pipeline 211 is a multi-layer reciprocating structure.

[0074] In this way, the area for absorbing heat from the shunt resistor chip 2 can be increased, and the heat dissipation efficiency can be improved.

[0075] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", etc. indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation and specific orientation structure and operation. Therefore, it cannot be understood as a limitation of the present invention. In addition, "first" and "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Therefore, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, the meaning of "a plurality" is two or more.

[0076] In the description of the present invention, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected" 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 or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0077] The above has described a specific embodiment of the present invention in detail, but the content described is only the preferred embodiment of the present invention and cannot be considered as limiting the scope of implementation of the present invention. Any equivalent changes and improvements made according to the scope of the application of the present invention should still fall within the scope covered by the patent of the present invention.

Claims

1. A high-precision DC shunt, characterized in that, Including: Loading plates (1), there are two loading plates (1) in the front and back, and the two loading plates (1) in the front and back are fixedly connected by bolts and nuts; Shunt resistor chips (2), the front and rear ends of the shunt resistor chips (2) are installed on the two loading plates (1); Current input mechanism (3), the current input mechanism (3) is connected to the front end of the shunt resistor chip (2); Current output block (4), the current output block (4) is fixedly connected to the rear end of the shunt resistor chip (2); Temperature sensor (5), the temperature sensor (5) is fixedly installed on the shunt resistor chip (2); Resistance compensation system (6), the resistance compensation system (6) is used to accurately measure the current value on the shunt resistor chip (2) in combination with a voltage measuring device.

2. The high-precision DC shunt according to claim 1, characterized in that, The resistance compensation system (6) receives the temperature value Ta provided by the temperature sensor (5), stores the resistance value Ra of the shunt resistor chip (2) at different temperatures in the resistance compensation system (6), and receives the voltage value Ua between the current input mechanism (3) and the current output block (4) measured by the voltage measuring device. Finally, the current value Ia passing through the shunt resistor chip (2) is measured by the ratio of the voltage value Ua and the resistance value Ra, that is, Ia = Ua / Ra.

3. A high-precision DC shunt according to claim 1, characterized in that, The resistance compensation system (6) includes an adjusting screw A (61), the adjusting screw A (61) is rotatably mounted between the two loading plates (1) in the front and back, and an angle measuring sensor A (62) coaxial with the adjusting screw A (61) for measuring the rotation angle of the adjusting screw A (61) is fixedly installed on one of the loading plates (1). The current input mechanism (3) includes a current input block (31), the current input block (31) is slidably sleeved on the shunt resistor chip (2), and the adjusting screw A (61) is threadedly connected to the current input block (31).

4. A high-precision DC shunt according to claim 1, wherein The shunt resistor chip (2) is composed of two overlapping pieces. The current input mechanism (3) includes a support rod (32), the support rod (32) corresponds to the position of the shunt resistor chip (2), a contact piece (33) is arranged between the two shunt resistor chips (2), the contact piece (33) is slidably mounted on the support rod (32), a safety motor (34) is fixedly installed on the support rod, the output shaft of the safety motor (34) is processed into a threaded shape, the output shaft of the safety motor (34) is threadedly connected to the contact piece (33), and the positive and negative poles of the safety motor (34) are respectively connected to the middle position of the contact piece (33) and the current output block (4) through wires.

5. A high-precision DC shunt according to claim 4, characterized in that, The support rod (32) is slidably mounted between two loading plates (1) in the front-rear direction. The resistance compensation system (6) includes an adjusting screw B (63), which is rotatably mounted between the front and rear loading plates (1). An angle measurement sensor B (64) that is coaxial with the adjusting screw B (63) and used to measure the rotation angle of the adjusting screw B (63) is fixedly installed on one of the loading plates (1). The adjusting screw B (63) is threadedly connected to the support rod (32).

6. A high-precision DC shunt according to claim 4 or 5, characterized in that, The contact piece (33) includes a contact fixing piece (331) and a contact elastic piece (332). The contact fixing piece (331) is slidably mounted on the support rod (32) and is threadedly connected to the output shaft of the safety motor (34). One contact elastic piece (332) is slidably connected to each of the two ends of the contact fixing piece (331) facing the shunt resistor chip (2). A spring (333) whose two ends are fixedly connected to the two contact elastic pieces (332) respectively is arranged between the two contact elastic pieces (332).

7. A high-precision DC shunt according to claim 1, characterized in that, The current input mechanism (3) includes a current input block (31), which is fixedly installed at the front end of the shunt resistor chip (2). There are two shunt resistor chips (2). One of the shunt resistor chips (2) is slidably connected to the loading plate (1), and the other shunt resistor chip (2) is fixedly connected to the loading plate (1). A safety motor (34) is fixedly connected to the front loading plate (1). The output end of the safety motor (34) is threadedly connected to the movable current input block (31).

8. A high-precision DC shunt according to any one of claims 1-3, characterized in that, The loading plate (1) has a disc-shaped structure. A plurality of shunt plates are evenly distributed along the circumference of the loading plate (1). A radiator fan (7) assembly is fixedly connected to the front end of the front loading plate (1) by bolts.

9. The high-precision DC shunt according to claim 8, wherein, A heat sink (21) is attached to the shunt resistor chip (2). Annular grooves (11) are formed on the outer sides of the loading plates (1). A heat dissipation pipeline (211) is formed in the heat sink (21). The front and rear sides of the heat dissipation pipeline (211) are respectively communicated with the annular grooves (11) in the front and rear loading plates (1). An abnormal-shaped heat dissipation pipe (8) is connected in series between the front and rear loading plates (1), and the abnormal-shaped heat dissipation pipe (8) is communicated with the annular groove (11). The abnormal-shaped heat dissipation pipe (8) passes through the front end of the radiator fan (7) assembly. The heat dissipation pipeline (211) has a multi-layer reciprocating structure.

10. A high-precision DC shunt according to claim 9, characterized in that, A plurality of heat dissipation fins (81) are fixedly installed at the position where the abnormal-shaped heat dissipation pipe (8) is located at the front end of the radiator fan (7) assembly.

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