Novel resistance-type current detector

Abstract

A novel resistance type current detector comprises a metal resistor and a metal through-flow row which is in conductive connection with the two sides of the metal resistor in the current direction. And the anode and cathode signal sampling area is directly and conductively connected with the metal resistor and is isolated from the metal through-flow bar. The positive and negative electrode signal sampling areas isolated from the metal through-flow row are arranged at one end or two ends of the metal resistor, so that the interference of the resistor of the metal through-flow row on voltage sampling when large current is conducted is avoided, meanwhile, the Seebeck effect is reduced to the greatest extent, the detection error is reduced, and the current detection precision is improved.

Description

Technical Field

[0001] This invention relates to the field of electronics, specifically to a resistive current detector for detecting current. Background Technology

[0002] With the rapid development of new energy vehicles and the wind, solar and energy storage industries, current sensors are used to accurately measure the operating current of batteries, which is the foundation for SOC (State of Charge) assessment, fault diagnosis and protection functions. At present, current detectors and current sensors are widely used due to their advantages such as high accuracy and low cost, but problems such as heat generation, response time delay and accuracy being affected by temperature still exist.

[0003] Existing resistive current detector structures on the market include... Figure 1 As shown, the device includes a metal resistor 1 and metal busbars 2 located on both sides of the metal resistor 1 in the direction of current. The metal resistor 1 is located in the middle of the current detector and serves as the main resistance. The metal busbars 2 are located on both sides of the metal resistor 1 in the direction of current and are connected to the metal resistor 1 to facilitate current flow and provide a fixed installation. The metal resistor 1 and the metal busbars 2 are made of two different metal materials.

[0004] In existing current detector structures, both positive and negative signal sampling points are led out from a metal busbar 2. The methods of leading out include soldering PCB patches 3 to one end of the metal busbar near the metal resistor 1, providing threaded holes 4 for bolted connections to the sampling circuit, or using terminals 5. Because the metal resistor 1 and the metal busbar 2 are made of different metal materials, a Seebeck effect occurs. When there is a temperature difference between the two sampling points due to environmental factors or heat dissipation, the resulting thermoelectric potential difference at the two sampling points will cause a significant deviation in the voltage sampling signal, thus affecting the accuracy of current detection. Summary of the Invention

[0005] The purpose of this invention is to provide a voltage signal sampling area that is completely isolated from the metal busbar on opposite sides of one or both ends of a resistive current detector, so as to avoid the interference of the resistance of the metal busbar on the voltage sampling when a large current is applied, and at the same time minimize the Seebeck effect and improve the detection accuracy.

[0006] To achieve the above objectives, the present invention provides a novel resistive current detector, comprising a metal resistor and a metal current bus that is electrically connected to both sides of the metal resistor in the current direction; the positive and negative signal sampling areas are directly electrically connected to the metal resistor and completely isolated from the metal current bus.

[0007] Preferably, the positive and negative signal sampling areas are located on opposite sides of one or both ends of the metal resistor.

[0008] Preferably, one or both ends of the metal resistor protrude outside the metal current bus, and the positive and negative signal sampling areas are located on opposite sides of the same or both ends of the metal resistor that protrude from the metal current bus.

[0009] Preferably, a notch is provided at the end of the metal resistor where the signal sampling area is provided to lengthen the current loop length between the positive and negative sampling areas.

[0010] Preferably, the signal sampling area is formed by isolation grooves at the metal busbar connected to one or both ends of the metal resistor, and the signal sampling area is not connected to the metal busbar.

[0011] Preferably, the resistivity of the positive and negative signal sampling regions is less than the resistivity of the metal resistor.

[0012] Preferably, the signal sampling area has a block structure, and its shape is rectangular, square, semi-circular or triangular.

[0013] By setting positive and negative sampling areas (signal sampling areas) on the metal resistor that are completely isolated from the metal busbar, the heat energy of the metal busbar cannot be transferred to the signal sampling area, thus minimizing the Seebeck effect, reducing detection error, and improving detection accuracy.

[0014] When the materials of the positive and negative sampling areas are the same as those of the metal resistor, the Seebeck effect can be eliminated, and the detection accuracy can be improved.

[0015] The metal block with a small resistance value in the positive and negative sampling areas can uniformly measure the signal value at each point on the signal sampling pin, making the signal sampling more stable and accurate, and also facilitating operations such as soldering when connecting external leads.

[0016] By setting notches and slots on the ends of metal resistors with positive and negative sampling areas, the current loop length between the positive and negative signal sampling areas is increased, which can amplify the signal amplitude and help improve the accuracy of signal sampling. This is because excessively small sampling signals are easily interfered with, and multiple stages of amplification and filtering are required for excessively small signals, which is not conducive to the design of subsequent sampling circuits. Attached Figure Description

[0017] Figure 1 Figure A shows the PCB surface mount configuration, Figure B shows the bolt connection configuration with threaded holes, and Figure C shows the configuration with terminals.

[0018] Figure 2 This is a schematic diagram of the structure of signal sampling areas set on opposite sides of the same end of a metal resistor.

[0019] Figure 3 This is a schematic diagram of the structure of signal sampling areas set on opposite sides of the two ends of a metal resistor.

[0020] Figure 4 This is a schematic diagram of a structure in which signal sampling areas are set on opposite sides of one end of a metal resistor that protrudes from the metal busbar.

[0021] Figure 5 Is Figure 4 A schematic diagram of a metal resistor with a signal sampling area having a notch or slot at its end.

[0022] Figure 6 This is a schematic diagram of a structure in which signal sampling areas are set on opposite sides of the two ends of a metal resistor protruding from a metal current bus.

[0023] Figure 7 Is Figure 6 A schematic diagram of a metal resistor with a signal sampling area on it, wherein notches and slots are opened at both ends.

[0024] Figure Labels

[0025] 1. Metal resistor; 2. Metal busbar; 3. Soldered PCB patch; 4. Threaded hole; 5. Terminal block; 6. Signal sampling area; 7. Notch; 8. Isolation slot. Detailed Implementation

[0026] The resistive current detector of the present invention includes a metal resistor and a metal current bus that is conductively connected to both sides of the metal resistor in the current direction; the positive and negative signal sampling areas are directly conductively connected to the metal resistor and completely isolated from the metal current bus.

[0027] The aforementioned positive and negative sampling regions are located at one or both ends of a metal resistor parallel to the current direction and the current detector, respectively.

[0028] The following describes preferred embodiments in detail with reference to the accompanying drawings. The directional terms used are for reference only and do not constitute a limitation on the technical solution of this invention.

[0029] See Figure 2 and Figure 3 The current detector includes a metal resistor 1 and metal current buses 2 located on both sides of the metal resistor 1. The metal resistor 1 and the metal current buses 2 are connected by welding, and the metal resistor 1 and the metal current buses 2 have the same width. The metal materials of the metal resistor 1 and the metal current buses 2 are different, and the metal resistor 1 is preferably made of a metal alloy.

[0030] The two signal sampling areas 6 (positive and negative signal sampling areas) are directly conductively connected to the metal resistor 1, but completely physically isolated from the metal busbar 2 via the isolation groove 8. That is, the signal sampling areas 6 and the metal busbar 2 are not connected at all. The two signal sampling areas 6 have a block-like structure, and their material can be different from that of the metal resistor 1. For example, the material of the signal sampling areas 6 can be the same as that of the metal busbar 2, or it can be a conductive material with a resistivity lower than that of the metal resistor 1, or it can be another metal material. The signal sampling areas 6 can have various structural shapes such as rectangles, squares, semicircles, and triangles. Since the signal sampling area 6 is not connected to the metal busbar 2, the heat energy on the metal busbar 2 cannot be transferred to the signal sampling area 6. Therefore, the temperature of the metal busbar 2 does not affect the temperature of the signal sampling area 6. The temperature of the signal sampling area 6 is only affected by the ambient temperature and the temperature at the metal resistor 1. The two signal sampling areas 6 have almost the same temperature. Furthermore, because the current path and the voltage sampling path are completely isolated, the influence of the resistance of the metal busbar on the sampling voltage under high current is minimized. Therefore, the Seebeck effect can be eliminated, and the influence of thermoelectric potential on the positive and negative sampling signals can be removed, improving detection accuracy. When the resistivity of the signal sampling area 6 is less than the resistivity of the metal resistor 1, the signal value at each point on the signal sampling pin can be uniformly distributed, making signal sampling more stable and accurate. This also facilitates operations such as soldering when connecting external leads.

[0031] The way the signal sampling area 6 is set on the metal resistor 1 can vary. See [link / reference] Figure 2 Two signal sampling regions 6 are set on opposite sides of the same end of the metal resistor 1, parallel to the current direction; see [link / reference] Figure 3 Two signal sampling areas 6 are set on opposite sides of the two ends of the metal resistor 1 that are parallel to the current direction.

[0032] A notch 7 is provided on one side of the metal resistor 1 between the two signal sampling areas 6 to lengthen the current loop length between the two signal sampling areas 6, thereby increasing the sampling signal and improving the detection accuracy.

[0033] See Figure 4 and Figure 5 One or both ends of a metal resistor 1, parallel to the current direction, protrude outside the metal current bus 2. Two signal sampling areas 6 are set on one or both ends of the metal resistor 1 that protrude from the metal current bus 2, and the signal sampling areas 6 are not connected to the metal current bus 2. With this configuration, it is not necessary to create an isolation groove 8 on the metal current bus 2.

[0034] See Figure 6 and Figure 7A notch 7 is provided on one side of the metal resistor 1 between the two signal sampling areas 6 to lengthen the current loop length between the two signal sampling areas 6. The width and depth of the notch 7 can affect the equivalent resistance value of the sampling. By adjusting the depth and width of the notch, the equivalent sampling resistance value can be adjusted, ultimately affecting the amplitude of the sampled signal and thus improving the sampling accuracy.

Claims

1. A novel resistive current detector, characterized in that, It includes a metal resistor and a metal bus that is electrically connected to both sides of the metal resistor in the direction of current; the positive and negative signal sampling areas are directly electrically connected to the metal resistor and completely isolated from the metal bus.

2. The resistive current detector according to claim 1, characterized in that, The positive and negative signal sampling areas are located on opposite sides of one or both ends of the metal resistor.

3. The resistive current detector according to claim 1, characterized in that, One or both ends of the metal resistor protrude outside the metal current bus, and the positive and negative signal sampling areas are located on opposite sides of the same or both ends of the metal resistor that protrude from the metal current bus.

4. The resistive current detector according to claim 2 or 3, characterized in that, A notch or slot is provided at the end of the metal resistor where the signal sampling area is located to lengthen the current loop between the positive and negative signal sampling areas.

5. The resistive current detector according to claim 1, characterized in that, The signal sampling area is formed by isolating the metal busbar connected to one or both ends of the metal resistor through isolation grooves. The signal sampling area is not connected to the metal busbar.

6. The resistive current detector according to claim 1, characterized in that, The resistivity of the positive and negative signal sampling regions is less than the resistivity of the metal resistor.

7. The resistive current detector according to claim 1, characterized in that, The signal sampling area has a block structure, and its shape is rectangular, square, semi-circular or triangular.

Images