Hall current sensor, motor control system and vehicle

Abstract

The invention discloses a Hall current sensor, a motor control system and a vehicle, and belongs to the technical field of sensors. The Hall current sensor comprises a PCB (Printed Circuit Board), three Hall elements are vertically fixed on the surface of one side of the PCB, and each Hall element can be inserted into the corresponding air gap; the PCB is provided with a connecting hole for a conductive copper needle to penetrate through and a mounting hole matched with the connecting part to fix the PCB, and the connecting hole and the mounting hole are formed in the two sides of the central axis of the PCB respectively, so that two stress points are formed on the PCB; at least one through hole is formed in the PCB around the pin position of each Hall element in the length direction of the PCB, and a glue injection head applies force to any through hole in the two ends of the PCB, so that the PCB is stressed and pressed downwards and is bonded through the filled adhesive, and the glue injection head is connected with the PCB. And tilting deformation of two ends of the PCB caused by two force bearing points can be reduced.

Description

Technical Field

[0001] This invention relates to the field of Hall current sensors, specifically to a Hall current sensor, a motor control system, and a vehicle, and is particularly applicable to motor control systems for new energy vehicles. Background Technology

[0002] Hall effect current sensors are key components in power electronic systems, used to measure current magnitude and convert it into a usable electrical signal. They are widely used in industrial control, power systems, and new energy vehicles. Among them, Hall effect current sensors are widely used in various current detection scenarios due to their advantages such as non-contact measurement, good isolation, and fast response speed.

[0003] Currently, the most common Hall current sensors on the market are mainly of two structures: open-loop and closed-loop. Open-loop Hall current sensors have a simple structure and low cost, but their accuracy and linearity are relatively low; closed-loop Hall current sensors form a closed-loop control through a compensation coil, which has higher accuracy and better linearity, but their structure is complex and their cost is higher.

[0004] Patent application CN120314626A discloses a current sensor device for motor control, comprising: a PCB board, a Hall element vertically fixed on the front of the PCB board, two supports symmetrically arranged on both sides of the Hall element, the two supports being fixed on the PCB board, a clamping opening at the front end of the two supports, a magnetic core being fixed to the two supports through the clamping opening, a sensing port being opened above the magnetic core, the two supports being symmetrically arranged on both sides of the sensing port, the Hall element being centered in the sensing port, a front end cover being provided on the front side of the PCB board, and a first assembly structure being provided inside the front end cover to ensure that the Hall element, magnetic core and PCB board do not become misaligned during assembly.

[0005] However, after the conductive copper needles are inserted through the connecting holes and soldered, the mounting holes on the PCB circuit board are fixed to the connecting parts by screws. The soldering point and the screw fastening point form two stress points. Along the length of the PCB circuit board, the stress in the middle is greater than that at both ends. Due to the influence of the PCB circuit board material (FR-4 material), slight warping deformation will occur at both ends. Since the Hall sensor is located at the deformed positions at both ends, the relative position of the Hall sensor and the air gap will be misaligned, resulting in a decrease in the detection accuracy of the Hall sensor. Summary of the Invention

[0006] 1. The problem to be solved In view of the technical problems existing in the prior art, the present invention provides a Hall current sensor that reduces the warping deformation at both ends of the PCB circuit board caused by two stress points, thereby improving the measurement accuracy of the Hall element.

[0007] Another object of the present invention is to provide a motor control system having the above-described Hall current sensor.

[0008] Another object of the present invention is to provide a vehicle having a motor control system.

[0009] 2. Technical Solution To solve the above problems, the technical solution adopted by the present invention is as follows: The first aspect of the present invention provides a Hall current sensor, comprising: A housing for mounting the compatible components is provided, the housing having a receiving cavity, wherein a positioning part is provided in the receiving cavity for passing through a three-phase copper busbar; a wiring part is provided between any two adjacent positioning parts, the conductive copper pin of the wiring part extends into the receiving cavity, and a connecting part is provided in the receiving cavity relative to the conductive copper pin. During assembly, this ensures that the Hall element, magnetic core component, and PCB circuit board will not be misaligned, and ensures that the Hall element is in the air gap of the magnetic core component. When the magnetic field induces a signal, signal accuracy is guaranteed, and product quality is improved. The magnetic core component is provided on the positioning part, and the magnetic core component has an air gap. Each magnetic core component can generate a magnetic flux corresponding to the current flowing in the copper busbar. A PCB circuit board capable of outputting a signal corresponding to the magnetic flux density in the air gap has three Hall elements (the pins of the Hall elements are fabricated on the PCB circuit board using PCB soldering technology) vertically fixed on one side of the PCB circuit board. Each Hall element can be inserted into the corresponding air gap. The PCB circuit board is provided with a connection hole for conductive copper pins to pass through and a mounting hole that cooperates with the connection part to fix the PCB circuit board. The connection hole and the mounting hole are respectively located on both sides of its central axis, so that two force points are formed on the PCB circuit board. Along the length of the PCB circuit board, at least one through hole is formed on the PCB circuit board surrounding the pin position of each Hall element. The dispensing head applies force to either through hole at both ends of the PCB circuit board, causing the PCB circuit board to be pressed down and bonded by the filling adhesive. This can reduce the warping deformation of the PCB circuit board at both ends caused by the two force points, thereby improving the measurement accuracy of the Hall element.

[0010] According to any embodiment of the first aspect of the present invention, when the Hall element is inserted into the air gap, the projection of the through hole on the PCB circuit board onto the magnetic core component can partially coincide with the air gap.

[0011] According to any embodiment of the first aspect of the present invention, the outline center line of the through hole is located on the same straight line along the length direction of the PCB circuit board.

[0012] According to any embodiment of the first aspect of the present invention, the outline shape of the through hole is circular, square, elliptical or other regular shape.

[0013] According to any embodiment of the first aspect of the present invention, the outline shape of the through hole is circular, wherein the diameter of the middle through hole is consistent, the diameter of the two side through holes is consistent, and the diameter of the middle through hole is less than or equal to the diameter of the two side through holes.

[0014] In any embodiment of the first aspect of the invention, the Hall element is located at the exact center of the air gap, such that the magnetic core components are mounted on both sides of the Hall element with a fixed air gap.

[0015] According to any embodiment of the first aspect of the present invention, the diameter of the through hole ranges from 0.5 to 1.0 mm, preferably 0.8 mm.

[0016] According to any embodiment of the first aspect of the present invention, the through-hole is configured to inject epoxy resin adhesive through a dispensing head, the adhesive viscosity being in the range of 200-500 cPs.

[0017] According to any embodiment of the first aspect of the present invention, the air gap width of the magnetic core component is 0.8-1.2 mm, and the centering deviation of the Hall element is ≤0.02 mm.

[0018] According to any embodiment of the first aspect of the present invention, a positioning post is provided in the receiving cavity, and the PCB circuit board has a positioning hole that mates with the positioning post.

[0019] According to any embodiment of the first aspect of the invention, an end cap adapted to the housing is further included, the end cap being capable of covering the magnetic core component and the PCB circuit board.

[0020] A second aspect of the present invention provides a motor control system having a Hall current sensor as described in the first aspect above. The Hall current sensor provides a current signal to an MCU (microcontroller) for calculating magnetic field and torque, etc.

[0021] A third aspect of the present invention provides a vehicle having the motor control system described in the second aspect above, wherein the vehicle can accurately detect current signals through the motor control system, with a current measurement error of ±0.5%, thereby ensuring safe vehicle operation.

[0022] 3. Beneficial effects Compared with the prior art, the beneficial effects of the present invention are as follows: (1) The dispensing head of the present invention applies force to any through hole at both ends of the PCB circuit board, so that the PCB circuit board is pressed down by force and is cured and bonded by the filled adhesive, which can reduce the warping deformation of the two ends of the PCB circuit board caused by the two force points, thereby improving the measurement accuracy of the Hall element. (2) By opening through holes on both sides of the Hall element on the PCB circuit board and combining the bottom-up glue injection process, the present invention solves the problem that bubbles tend to accumulate at the Hall element during the glue injection process of traditional current sensors. After SEM imaging verification, the bubble rate of the present invention is less than 1%, while the bubble rate in the prior art is more than 2%, which makes the magnetic field sensed by the Hall element accurate and improves the reliability of the current sensor. Since some bubbles are effectively eliminated, the current measurement error is reduced from the traditional ±1% to ±0.5%, and the measurement accuracy is significantly improved. (3) The number of air bubbles in the encapsulation layer of the current sensor of the present invention is reduced, thereby improving its insulation performance; in terms of reliability, the present invention has no performance decay after 1000 temperature cycles (-40℃~125℃) and no adhesive layer cracking under vibration test conditions (frequency 10-2000Hz, acceleration 50m / s²), ensuring the stable operation of the current sensor in the high vibration environment of new energy electric vehicles. Attached Figure Description The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. However, it should be understood that these drawings are designed for illustrative purposes only and are not intended to limit the scope of the present invention. Furthermore, unless specifically indicated, these drawings are intended only to conceptually illustrate the structural construction described herein and are not necessarily drawn to scale.

[0023] Figure 1 This is a schematic diagram of the Hall current sensor of the present invention; Figure 2 This is an exploded structural diagram of the Hall current sensor of the present invention; Figure 3 This is a schematic diagram of the end cap-less structure of the Hall current sensor of the present invention; Figure 4 This is a three-dimensional structural schematic diagram of the PCB circuit board of Embodiment 1 of the present invention; Figure 5 for Figure 4 The main view; Figure 6 This is a schematic diagram of the PCB circuit board structure of Embodiment 2 of the present invention; Figure 7 This is a schematic diagram of the PCB circuit board structure of Embodiment 3 of the present invention; Figure 8 This is a schematic diagram of the PCB circuit board of embodiment 4 of the present invention; Figure 9This is a schematic diagram of the PCB circuit board of embodiment 5 of the present invention; Figure 10 This is a schematic diagram of the housing structure of the Hall current sensor of the present invention; Figure 11 This is a schematic diagram of the motor control system of the present invention; Figure 12 This is a schematic diagram of the assembly structure of the Hall current sensor and the three-phase copper busbar of the present invention; Figure 13 This is a partial schematic diagram of a Hall current sensor in the prior art.

[0024] Explanation of reference numerals in the attached figures: 100. Outer shell; 110. Receiving cavity; 120. Positioning part; 130. Copper busbar; 140. Connecting part; 150. Wiring part; 151. Conductive copper pin; 160. Positioning post; 200. Magnetic core components; 210. Air gap; 300. Magnetic induction component; 310. PCB circuit board; 311. Through hole; 312. Connecting hole; 313. Mounting hole; 314. Positioning hole; 315. Central axis; 320. Hall element; 400. End cap. Detailed Implementation

[0025] The following detailed description of exemplary embodiments of the invention is taken with reference to the accompanying drawings, which form part of the description and illustrate exemplary embodiments in which the invention may be practiced. While these exemplary embodiments have been described in sufficient detail to enable those skilled in the art to practice the invention, it should be understood that other embodiments may be implemented and various changes may be made to the invention without departing from the spirit and scope thereof. The more detailed description of embodiments of the invention below is not intended to limit the scope of the claimed invention, but is merely illustrative and not restrictive of the description of the features and characteristics of the invention, to suggest the best mode for carrying out the invention, and is sufficient to enable those skilled in the art to practice the invention. Therefore, the scope of the invention is defined only by the appended claims.

[0026] The following detailed description and exemplary embodiments of the invention can be better understood in conjunction with the accompanying drawings, wherein the elements and features of the invention are identified by reference numerals.

[0027] Example 1 like Figures 1 to 5 as well as Figures 10 to 12 As shown, the Hall current sensor in this embodiment includes a housing 100, a magnetic core component 200, a PCB circuit board 310, and an end cap 400.

[0028] Among them, such as Figure 10As shown, the housing 100 is used for mounting the phase adapter. The housing 100 is provided with a receiving cavity 110, in which a positioning part 120 is provided to accommodate a three-phase copper busbar 130. A wiring part 150 is provided between any two adjacent positioning parts 120. The conductive copper pin 151 of the wiring part 150 extends into the receiving cavity 110. A connecting part 140 is provided in the receiving cavity 110 relative to the conductive copper pin 151. During assembly, it is ensured that the Hall element 320, the magnetic core component 200 and the PCB circuit board 310 are not tilted as much as possible. It is ensured that the Hall element 320 is in the air gap 210 of the magnetic core component 200. When the magnetic field sensing signal is received, the signal accuracy is guaranteed and the product quality is improved.

[0029] In this embodiment, as Figure 3 As shown, the magnetic core component 200 is disposed on the positioning part 120, and an air gap 210 is provided on the magnetic core component 200. Each magnetic core component 200 can generate a magnetic flux corresponding to the current flowing in the copper busbar 130.

[0030] Furthermore, the air gap 210 of the magnetic core component 200 has a width of 0.8-1.2mm, the centering deviation of the Hall element 320 is ≤0.02mm, and the Hall element 320 is located at the exact center of the air gap 210, ensuring that the Hall element 320 is in the center position of the magnetic field, so that the magnetic core component 200 is assembled on both sides of the Hall element 320 with a fixed air gap 210, thereby improving the measurement accuracy.

[0031] like Figure 4 and Figure 5 As shown, a PCB circuit board 310 is capable of outputting a signal corresponding to the magnetic flux density in the air gap 210. Three Hall elements 320 (the pins of the Hall elements 320 are fabricated on the PCB circuit board 310 by PCB soldering) are fixed vertically and equally spaced on one side of the PCB circuit board 310. Each Hall element 320 can be inserted into the corresponding air gap 210. The PCB circuit board 310 is provided with a connection hole 312 for the conductive copper pin 151 to pass through and a mounting hole 313 that cooperates with the connection part 140 to fix the PCB circuit board 310. The connection hole 312 and the mounting hole 313 are respectively located on both sides of its central axis 315, so that two force points are formed on the PCB circuit board 310.

[0032] It should be noted that in this embodiment, the three Hall elements 320320 can be arranged perpendicularly to the PCB circuit board 310310. The distance between two adjacent Hall elements 320320 is not specifically limited; they can be fixed at equal vertical intervals or at non-equal vertical intervals on the PCB circuit board 310310. For ease of manufacturing, this embodiment adopts a vertically equal-interval fixing method.

[0033] In this embodiment, the PCB circuit board 310 can be made of FR-4 material (glass fiber reinforced epoxy resin material) with a thickness of 1.6mm, and the diameter of the through hole 311 ranges from 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, to 1.0mm, preferably 0.8mm.

[0034] However, in actual production, it was found that after the conductive copper needle 151 passes through the connecting hole 312 and is soldered, the mounting hole 313 on the PCB circuit board 310 is fixed to the connecting part 140 by screws. The soldering point and the screw fastening point form two stress points. Along the length of the PCB circuit board 310, the stress in the middle is greater than that at both ends. Due to the influence of the material of the PCB circuit board 310 (FR-4 material), slight warping deformation will occur at both ends. The Hall sensor is located at the deformed position at both ends, causing the relative position of the Hall sensor and the air gap 210 to be misaligned, resulting in a decrease in the detection accuracy of the Hall sensor.

[0035] In this invention, after extensive testing, at least one through hole 311 is formed on the PCB circuit board 310 along its length and around the pin positions of each Hall element 320. The dispensing head applies force to any one of the through holes 311 at both ends of the PCB circuit board 310, causing the PCB circuit board 310 to be pressed down and cured by the filled adhesive. This reduces the warping deformation at both ends of the PCB circuit board 310 caused by the two force points, thereby improving the measurement accuracy of the Hall element 320.

[0036] It is important to emphasize that, in general, the adhesive for current sensors is applied by dripping it onto the product from above, and then relying on the adhesive's fluidity to flow down to the area below the PCB circuit board 310. However, the structure below the PCB circuit board 310 is relatively complex. The gaps between the PCB circuit board 310 and the magnetic core component 200, the magnetic core component 200 and the Hall element 320, and the magnetic core component 200 and the housing 100 are very small, making it easy for air bubbles to form. Figure 13 As shown, when the adhesive is poured into the sensor, areas with complex structures cannot be completely soaked in the adhesive in a short time, but are surrounded by a large amount of adhesive, thus forming air bubbles surrounded by adhesive.

[0037] Because the adhesive flows from top to bottom, bubbles initially accumulate at the bottom of complex structures. As buoyancy increases, the bubbles rise, encountering resistance primarily from the adhesive's viscosity. Some small bubbles may fail to overcome this viscosity and remain trapped within the sensor. Larger bubbles, without obstruction, eventually rise to the surface of the adhesive, bursting to form uneven pits. In complex structures, bubble ascent is hindered. When bubbles encounter obstacles while rising in complex environments, they tend to adhere to the surface of these obstacles, making the Hall element 320 a prime target for bubble adhesion.

[0038] However, irregularly distributed air bubbles weaken the magnetic field, thus affecting the measurement accuracy of the Hall element 320. When a current IP flows through the copper busbar 130 of the sensor, a source magnetic field H is generated around the busbar 130. This magnetic field is collected by the magnetic core component 200 and conducted to the Hall element 320 at the center of the air gap 210. When there are no air bubbles, the entire air gap 210 is covered by epoxy resin adhesive. Assuming its permeability is u1, the magnetic induction intensity B of the Hall element 320 is B = u1H. At this time, the magnetic field is uniformly and linearly distributed in the epoxy resin. When air bubbles are irregularly attached to the surface of the Hall element 320, the permeability of the air bubbles is different from u1, and the value of the magnetic induction intensity B cannot be determined linearly. Especially when measuring alternating current, the alternating current generates an alternating magnetic field. The permeability u is a function of the magnetic field frequency w. The presence of air bubbles causes irregular abrupt changes in the permeability. Therefore, the presence of air bubbles affects the measurement accuracy of the Hall element 320.

[0039] In this embodiment, as Figure 4 and Figure 5 As shown, the outline of the through hole 311 is circular, and there are six through holes 311. Each pair of through holes 311 is symmetrically distributed on both sides of the corresponding pin position of the Hall element 320. Adhesive can be filled between the PCB circuit board 310 and the Hall element 320 through the through holes 311 and cured to form an encapsulation layer (not shown in the figure). The encapsulation layer can encapsulate the PCB circuit board 310 in the housing 100.

[0040] In this embodiment, as Figure 5 As shown, when the Hall element 320 is inserted into the air gap 210, the projection of the through hole 311 on the PCB circuit board 310 onto the magnetic core component 200 can partially coincide with the air gap 210. On the one hand, this helps the dispensing head to effectively avoid the magnetic core component 200 when applying downward pressure, thus preventing damage to the dispensing head; on the other hand, the adhesive can extend towards the air gap 210, preventing adhesive overflow.

[0041] Furthermore, the projection of the Hall element 320 onto the magnetic core component 200 coincides with the air gap 210, which helps ensure that the Hall element 320 is accurately located in the air gap 210, thereby enabling precise detection of magnetic field changes in the magnetic core air gap 210. This design ensures that the sensing center of the Hall element 320 is always located at the geometric center of the magnetic core air gap 210, resulting in good installation consistency and thus guaranteeing the consistent performance of the sensor.

[0042] Furthermore, the center line of the through hole 311 is located on the same straight line along the length of the PCB circuit board 310. On the one hand, this avoids the stress forming a lateral component inside the board due to the offset of the center line of the through hole 311, reducing the risk of cracking of the PCB substrate (such as FR-4) due to the chaotic force direction. On the other hand, the through holes 311 on the same straight line can share the pressure of the dispensing head, avoiding deformation of the through hole 311 due to the concentration of force on a single through hole 311.

[0043] The diameters of the central through holes 311 and the diameters of the two through holes 311 are the same, and the diameter of the central through hole 311 is less than or equal to the diameter of the two through holes 311, which can provide a larger force application surface for the dispensing head.

[0044] Furthermore, the through hole 311 is configured to inject epoxy resin adhesive through a dispensing head, using epoxy resin potting to enhance insulation, durability, and mechanical strength, thereby improving product reliability. The adhesive viscosity range is 200-500 cPs, and the dispensing process adopts a bottom-up dispensing process. The adhesive fills the gap between the magnetic core component 200 and the PCB circuit board 310 through the through hole 311, effectively squeezing out air.

[0045] Depending on the type of adhesive used, the encapsulation layer can be transparent or opaque.

[0046] Three pairs (six) of through holes 311 are formed on the PCB circuit board 310. The dispensing head is inserted into the six through holes 311, which allows the air in the gaps to be discharged through the gaps when the adhesive is injected into the PCB circuit board 310, effectively preventing the formation of air bubbles around the Hall element 320 and improving the dispensing efficiency.

[0047] The Hall current sensor obtained in this embodiment is tested, and the testing method includes: 1) X-ray inspection: Using X-rays to observe the distribution of bubbles inside the encapsulation layer; 2) Ultrasonic testing: Using an ultrasonic detector to detect air bubbles in the encapsulation layer; 3) Partial discharge detection: Use a partial discharge detection system to monitor the discharge status of the current sensor under high voltage environment and evaluate the insulation performance; 4) Withstand voltage test: Conduct a withstand voltage test to check whether the current sensor of this embodiment can withstand high voltage without breakdown.

[0048] After testing, the number of bubbles in the encapsulation layer of the current sensor of this embodiment is small and the size is small, which cannot be observed by the naked eye, and the electrical insulation is good. This current sensor has passed the withstand voltage test of 1000VAC for 60s, the leakage current ≤ 0.1mA, the upper limit value is 1mA, and the withstand voltage test is qualified.

[0049] This product avoids the generation of bubbles by changing the PCB structure and the glue filling method. Six glue filling holes are opened near the Hall element 320 of this product, and the adhesive is squeezed in through the glue injection head inserted into the hole. This can make the adhesive fill the complex structure first when injecting downward into the PCB circuit board 310, squeeze out the air below, and make the adhesive spread from the bottom upward, effectively preventing the formation of bubbles, and greatly improving the glue filling efficiency.

[0050] Since the sensor is installed on a new energy vehicle, there are a large number of vibration conditions. If bubbles adhere to the wall of the housing 100, under long-term vibration, the housing and the glue layer will crack, causing the sensor to be exposed to a possibly contaminated environment, resulting in the risk of circuit short-circuit and product failure.

[0051] In this embodiment, a positioning post 160 is provided in the accommodation cavity 110, and the PCB circuit board 310 is provided with a positioning hole 314 adapted to the positioning post 160. In addition, there is an end cover 400 adapted to the housing 100, and the end cover 400 can cover the magnetic core component 200 and the PCB circuit board 310.

[0052] The motor control system of the present invention has the above-mentioned Hall current sensor, as Figure 11 and Figure 12 shown, provides a current signal for the MCU to calculate the magnetic field, torque, etc., to ensure the safe driving of the vehicle.

[0053] Example 2 As Figure 6 shown, the structure of this embodiment is basically the same as that of Embodiment 1. The difference is that along the length direction of the PCB circuit board 310 and around the pin positions of the Hall element 320, four through holes 311 are formed on the PCB circuit board 310. The contour shape of the through holes 311 is circular. Two of the through holes 311 are respectively located on both sides of the pin positions of the middle Hall element 320, and the remaining two through holes 311 correspond to the Hall elements 320 on both sides and are located outside. During operation, first apply force to inject glue into the middle through hole, and then apply force to inject glue into the through holes on both sides simultaneously.

[0054] Furthermore, adhesive can be filled between the PCB circuit board 310 and the Hall element 320 through the through hole 311 and cured to form an encapsulation layer.

[0055] Example 3 like Figure 7 As shown, the structure of this embodiment is basically the same as that of embodiment 1. The difference is that six through holes 311 are formed on the PCB circuit board 310 along the length of the PCB circuit board 310 and around the pin position of the Hall element 320. The outline shape of the through holes 311 is circular. Two through holes 311 are located on both sides of the pin position of the middle Hall element 320, and the remaining two through holes 311 correspond to the Hall elements 320 on both sides and are located on the inner side. During operation, the middle through hole is first injected with glue, and then the through holes on both sides are injected with glue at the same time.

[0056] Furthermore, adhesive can be filled between the PCB circuit board 310 and the Hall element 320 through the through hole 311 and cured to form an encapsulation layer.

[0057] Example 4 like Figure 8 As shown, the structure of this embodiment is basically the same as that of embodiment 1. The difference is that six through holes 311 are formed on the PCB circuit board 310 along the length of the PCB circuit board 310 and around the pin position of the Hall element 320. The outline shape of the through holes 311 is elliptical. Two through holes 311 are located on both sides of the pin position of the middle Hall element 320, and the remaining four through holes 311 correspond to the Hall elements 320 on both sides. When a small movement of the dispensing head is required, the elliptical through holes provide the possibility for a small adjustment of the dispensing head.

[0058] Furthermore, adhesive can be filled between the PCB circuit board 310 and the Hall element 320 through the through hole 311 and cured to form an encapsulation layer.

[0059] Example 5 like Figure 9 As shown, the structure of this embodiment is basically the same as that of embodiment 1. The difference is that six through holes 311 are formed on the PCB circuit board 310 along the length of the PCB circuit board 310 and around the pin position of the Hall element 320. The outline shape of the through holes 311 is square. Two through holes 311 are located on both sides of the pin position of the middle Hall element 320, and the remaining four through holes 311 correspond to the Hall elements 320 on both sides. The above-mentioned square through holes are in tangential contact with the dispensing head. There are four force points, the force area is small, and the pressure per unit area is high, which makes the PCB circuit board more firmly bonded and further reduces warping deformation.

[0060] Furthermore, adhesive can be filled between the PCB circuit board 310 and the Hall element 320 through the through hole 311 and cured to form an encapsulation layer.

[0061] The present invention and its embodiments have been described above illustratively. This description is not restrictive, and the figures shown are only one embodiment of the present invention; the actual structure is not limited thereto. Therefore, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the present invention, such designs should fall within the protection scope of the present invention.

Claims

1. A Hall current sensor, comprising: The outer casing (100) has a receiving cavity (110) therein, wherein a positioning part (120) is provided in the receiving cavity (110) for passing through a three-phase copper busbar (130); a wiring part (150) is provided between any two adjacent positioning parts (120), and a conductive copper pin (151) of the wiring part (150) extends into the receiving cavity (110), and a connecting part (140) is provided in the receiving cavity (110) opposite to the conductive copper pin (151). A magnetic core component (200) is disposed on the positioning part (120), and an air gap (210) is formed on the magnetic core component (200); characterized in that it further includes: The PCB circuit board (310) has three Hall elements (320) vertically fixed on one side of its upper surface. Each Hall element (320) can be inserted into the corresponding air gap (210). The PCB circuit board (310) is provided with a connection hole (312) for conductive copper pins (151) to pass through and a mounting hole (313) that cooperates with the connection part (140) to fix the PCB circuit board (310). The connection hole (312) and the mounting hole (313) are respectively located on both sides of its central axis (315), so that two force points are formed on the PCB circuit board (310). Along the length of the PCB circuit board (310), at least one through hole (311) is formed on the PCB circuit board (310) at the pin position surrounding each of the Hall elements (320). The dispensing head applies force to either through hole (311) at both ends of the PCB circuit board (310), causing the PCB circuit board (310) to be pressed down by force and bonded by the filled adhesive, which can reduce the warping deformation of the two ends of the PCB circuit board (310) caused by the two force points.

2. The Hall current sensor according to claim 1, characterized in that, When the Hall element (320) is inserted into the air gap (210), the projection of the through hole (311) on the PCB circuit board (310) onto the magnetic core component (200) can partially coincide with the air gap (210).

3. The Hall current sensor according to claim 1 or 2, characterized in that, The outline center line of the through hole (311) is located on the same straight line along the length direction of the PCB circuit board (310).

4. The Hall current sensor according to claim 3, characterized in that, The outline shape of the through hole (311) is circular, square, elliptical or other regular shape.

5. The Hall current sensor according to claim 4, characterized in that, The outline of the through hole (311) is circular, wherein the diameter of the middle through hole (311) is the same, the diameter of the two through holes (311) is the same, and the diameter of the middle through hole (311) is less than or equal to the diameter of the two through holes (311).

6. The Hall current sensor according to claim 5, characterized in that, The Hall element (320) is located at the center of the air gap (210), such that the magnetic core component (200) is assembled on both sides of the Hall element (320) with the air gap (210) fixed.

7. The Hall current sensor according to claim 6, characterized in that, The diameter of the through hole (311) ranges from 0.5 to 1.0 mm, preferably 0.8 mm.

8. The Hall current sensor according to claim 7, characterized in that, The through hole (311) is configured to inject epoxy resin adhesive through a dispensing head, with the adhesive viscosity ranging from 200 to 500 cPs.

9. The Hall current sensor according to claim 8, characterized in that, The air gap (210) width of the magnetic core component (200) is 0.8-1.2mm, and the centering deviation of the Hall element (320) is ≤0.02mm.

10. The Hall current sensor according to claim 9, characterized in that, The cavity (110) is provided with a positioning post (160), and the PCB circuit board (310) is provided with a positioning hole (314) that cooperates with the positioning post (160).

11. The Hall current sensor according to claim 1, characterized in that, It also includes an end cap (400) adapted to the housing (100), the end cap (400) being able to cover the magnetic core component (200) and the PCB circuit board (310).

12. A motor control system, characterized in that, The Hall current sensor, as described in any one of claims 1-11, provides a current signal to the MCU.

13. A vehicle, characterized in that, The motor control system according to claim 12 has a current measurement error of ±0.5%.

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