Detection method of current sensor compatible with IMC-HALL and differential Hall schemes

Abstract

The invention discloses a detection method of a current sensor compatible with IMC-HALL and differential Hall schemes, the detection method is realized through the current sensor compatible with the IMC-HALL and differential Hall schemes, the sensor comprises an injection molding shell, a copper bar unit, a circuit board and a signal switching pin, the copper bar unit, the circuit board and the signal switching pin are all installed on the injection molding shell, and the signal switching pin is installed on the injection molding shell. The circuit board is installed in the circuit board installation groove, and the circuit board is an IMC-HALL circuit board or a differential Hall circuit board according to detection requirements. According to the detection method of the current sensor compatible with the IMC-HALL and differential Hall schemes, the anti-crosstalk capability of the differential Hall scheme is enhanced, and compatible replacement of the differential Hall and the IMC-HALL is achieved at low cost in a short time.

Description

Technical Field

[0001] The present invention belongs to the technical field of current sensors, and in particular relates to a detection method for a current sensor compatible with IMC-HALL and differential Hall schemes. Background Art

[0002] In the three-phase current detection of the motor controller, according to the different detection methods of the magnetic field generated by the current, the current sensor scheme can be divided into open-loop Hall scheme (perpendicular magnetic field detection), IMC-HAll scheme (parallel magnetic field detection, see attached Figure 7 ), differential Hall scheme (differential magnetic field detection, see attached Figure 8 ).

[0003] The open-loop Hall solution is the most widely used, but its position is being challenged due to its size.

[0004] Differential Hall effect sensors have attracted attention due to their coreless nature. They can be injection molded onto copper busbars or even integrated into power modules, significantly optimizing the space available for motor controllers. However, the lack of a core for protection makes them susceptible to the effects of surrounding magnetic fields.

[0005] Traditional open-loop Hall and IMC-Hall solutions, thanks to the presence of magnetic cores or shields, effectively isolate external magnetic fields, providing the chip with a relatively pure magnetic field detection environment. Differential Hall, on the other hand, is exposed to various magnetic field interferences. Although the difference between the two Hall sensors can offset some of the interference, the effect is always limited, especially as power modules continue to shrink and phase spacing continues to narrow. A simple differential Hall solution cannot meet the miniaturization requirements of motor controllers.

[0006] Therefore, further improvements are made to the above problems. Summary of the Invention

[0007] The main purpose of the present invention is to provide a detection method for a current sensor that is compatible with IMC-HALL and differential Hall solutions, and to provide a solution that enhances the anti-crosstalk capability of the differential Hall solution and realizes compatible replacement of differential Hall and IMC-HALL in a low-cost and short-time manner.

[0008] To achieve the above objectives, the present invention provides a detection method for a current sensor compatible with IMC-HALL and differential Hall solutions, which is implemented by a current sensor compatible with IMC-HALL and differential Hall solutions. The current sensor compatible with IMC-HALL and differential Hall solutions includes an injection molded housing, a copper busbar unit, a circuit board, and a signal adapter pin. The copper busbar unit, the circuit board, and the signal adapter pin are all installed in the injection molded housing, wherein: The injection molded housing is provided with a circuit board mounting groove and a plurality of detection mounting channels, each of the detection mounting channels is provided with a U-shaped groove portion, an opening portion and a copper busbar mounting area, the U-shaped groove portion surrounds the opening portion and a shielding cover is mounted on the U-shaped groove portion, and the opening portion is located at the center of the shielding cover; The copper bar unit is provided with a plurality of detection copper bars, the number of the detection copper bars is consistent with the number of the copper bar installation areas, and the detection copper bars are installed one by one in the corresponding copper bar installation areas, and the positions of the detection copper bars surrounded by the corresponding shielding covers are provided with openings, and the opening portions are located in the openings; The circuit board is installed in the circuit board mounting slot and, depending on the detection requirements, the circuit board is an IMC-HALL circuit board or a differential Hall circuit board. Both the IMC-HALL circuit board and the differential Hall circuit board are provided with a plurality of chip mounting branches. The number of the chip mounting branches is consistent with the number of the detection copper bars and the chip mounting branches are located one by one in the middle of the corresponding shielding cover. The detection method is specifically implemented as follows: Step S1: When parallel magnetic field detection is required, the IMC-HALL circuit board is installed in the circuit board mounting slot. For the IMC-HALL circuit board, the IMC-HALL sensor chip is mounted on the side of the chip mounting branch close to the injection molded shell, and the IMC-HALL sensor chip is located directly above the center of the opening. The IMC-HALL sensor chip detects through a parallel magnetic field as follows: the current Ip generates a magnetic field B, which is converted into a parallel magnetic field B through the shielding cover. imc The IMC-HALL sensor core collects the parallel magnetic field B imc Convert it into B1 and B2, and output the difference between B1 and B2; Step S2: When differential magnetic field detection is required, the differential magnetic field detector is installed in the circuit board mounting slot. For the differential Hall circuit board, the side of the chip mounting branch close to the injection molded shell is plugged with a differential Hall chip and the differential Hall chip is built into the opening portion. The differential Hall chip performs detection through the differential magnetic field as follows: the current Ip generates a magnetic field B diff , the differential Hall chip detects the magnetic field B diff Magnetic field components B at different locations T and B B , and output the difference value.

[0009] As a further preferred technical solution of the above technical solution, the size of the opening is determined by electromagnetic simulation.

[0010] As a further preferred technical solution of the above technical solution, the height of the circuit board distance detection copper bus is adjusted according to the electromagnetic simulation and experimental test results to achieve the optimization of the two compatible solutions, and the circuit board is provided with a corresponding RC filtering circuit.

[0011] As a further preferred technical solution of the above technical solution, the shielding cover and the corresponding detection copper busbar are integrated by injection molding, and the size and shape of the shielding cover and the positional relationship between the shielding cover and the monitoring copper busbar are adjusted based on electromagnetic simulation (in addition to providing a parallel magnetic field to the IMC-Hall chip, the shielding cover also provides a magnetic field interference elimination function for the differential Hall sensor chip, which can effectively reduce the magnetic field interference caused by the power module or application environment).

[0012] As a further preferred technical solution of the above technical solution, the circuit board is fixedly installed in the circuit board mounting groove by self-tapping screws, and is connected to the signal adapter pins by welding. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention.

[0014] Figure 2 It is a cross-sectional view of the present invention.

[0015] Figure 3 It is a structural schematic diagram of the injection molded housing of the present invention.

[0016] Figure 4 Schematic diagram of the structure of the present invention (the injection molded housing is omitted).

[0017] Figure 5 Schematic diagram of a circuit board of the IMC-HALL solution of the present invention.

[0018] Figure 6 Schematic diagram of a circuit board for the differential Hall solution of the present invention.

[0019] Figure 7 It is a schematic diagram of the principle of the IMC-HALL solution of the present invention.

[0020] Figure 8 It is a schematic diagram of the principle of the differential Hall scheme of the present invention.

[0021] The reference numerals include: 100, injection-molded housing; 110, circuit board mounting groove; 120, detection mounting channel; 121, U-shaped groove; 122, opening; 123, copper busbar mounting area; 124, shielding cover; 125, nut; 130, bushing; 200, copper busbar unit; 210, detection copper busbar; 211, opening; 300, circuit board; 310, chip mounting branch; 311, IMC-HALL sensor chip; 312, differential Hall chip; 400, signal adapter pin. DETAILED DESCRIPTION

[0022] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are for illustrative purposes only, and those skilled in the art will readily appreciate other obvious variations. The basic principles of the present invention defined in the following description may be applied to other embodiments, variations, improvements, equivalents, and other technical solutions that do not depart from the spirit and scope of the present invention.

[0023] In the preferred embodiment of the present invention, those skilled in the art should note that the welding holes and the like involved in the present invention may be regarded as prior art.

[0024] Preferred embodiment.

[0025] like Figure 1-8 As shown, the present invention discloses a detection method for a current sensor compatible with IMC-HALL and differential Hall schemes, which is implemented by a current sensor compatible with IMC-HALL and differential Hall schemes. The current sensor compatible with IMC-HALL and differential Hall schemes includes an injection molded housing 100, a copper busbar unit 200, a circuit board 300 (i.e., a PCB board), and a signal adapter pin 400. The copper busbar unit 200, the circuit board 300, and the signal adapter pin 400 are all installed in the injection molded housing 100, wherein: The injection-molded housing 100 is provided with a circuit board mounting slot 110 and a plurality of detection mounting channels 120. Each detection mounting channel 120 is provided with a U-shaped slot 121, an opening 122, and a copper busbar mounting area 123. The U-shaped slot 121 (partially) surrounds the opening 122 and is provided with a (U-shaped) shielding cover 124 (with a consistent wall thickness throughout). The opening 122 is located at the center of the shielding cover 124 (the plastic thickness of the opening must be ensured to prevent injection molding failure and insufficient strength). The copper busbar unit 200 is provided with a plurality of detection copper busbars 210. The number of the detection copper busbars 210 is the same as the number of the copper busbar installation areas 123. The detection copper busbars 210 are installed one by one in the corresponding copper busbar installation areas 123. The positions of the detection copper busbars 210 surrounded by the corresponding shielding covers 124 (parts) are provided with openings 211, and the opening portions 122 are located in the openings 211. The circuit board 300 is installed in the circuit board mounting groove 110 and, depending on the detection requirements, the circuit board is an IMC-HALL circuit board or a differential Hall circuit board. Both the IMC-HALL circuit board and the differential Hall circuit board are provided with a plurality of chip mounting branches 310. The number of the chip mounting branches 310 is consistent with the number of the detection copper bars 210 and the chip mounting branches 310 are located one by one in the middle of the corresponding shielding cover 124. The detection method is specifically implemented as follows: Step S1: Figure 5 and Figure 7 As shown, when parallel magnetic field detection is required, the IMC-HALL circuit board is installed in the circuit board mounting slot 110. For the IMC-HALL circuit board, the chip mounting branch 310 is mounted with an IMC-HALL sensor chip 311 on the side close to the injection molded housing 100, and the IMC-HALL sensor chip 311 is located directly above the center of the opening 122. The IMC-HALL sensor chip 311 performs detection through a parallel magnetic field as follows: the current Ip generates a magnetic field B, which is converted into a parallel magnetic field B through the shielding cover. imc The IMC-HALL sensor core collects the parallel magnetic field B imc Convert it into B1 and B2, and output the difference between B1 and B2; Step S2: Figure 6 and Figure 8 As shown, when differential magnetic field detection is required, the differential magnetic field detector is installed in the circuit board mounting slot 110. For the differential Hall circuit board, the chip mounting branch 310 is connected to the side of the injection molded housing 100 with a differential Hall chip 312 and the differential Hall chip 312 is built into the opening portion 122. The differential Hall chip 312 performs detection through a differential magnetic field. The specific implementation is as follows: the current Ip generates a magnetic field B diff , the differential Hall chip detects the magnetic field B diff Magnetic field components B at different locations T and B B , and output the difference value.

[0026] Specifically, the size of the opening is determined by electromagnetic simulation.

[0027] More specifically, the height of the distance detection copper busbar on the circuit board is adjusted based on electromagnetic simulation and experimental test results to achieve the optimization of the two compatible solutions, and the circuit board is provided with a corresponding RC filtering circuit.

[0028] Furthermore, the shielding cover and the corresponding detection copper busbar are integrated by injection molding, and the size and shape of the shielding cover and the positional relationship between the shielding cover and the monitoring copper busbar are adjusted based on electromagnetic simulation (in addition to providing a parallel magnetic field to the IMC-Hall chip, the shielding cover also provides a magnetic field interference elimination function for the differential Hall sensor chip, which can effectively reduce the magnetic field interference caused by the power module or application environment).

[0029] Specifically, the copper busbar installation area 123 is provided with a nut 125 .

[0030] More specifically, the injection molded housing 100 is mounted with a plurality of bushings 130 .

[0031] Furthermore, the circuit board is fixedly mounted in the circuit board mounting slot by self-tapping screws, and is connected to the signal transfer pins by welding.

[0032] Preferably, the detection copper busbar, shielding cover, signal transfer pin, bushing and nut are formed into a whole through the injection molded shell, wherein the copper busbar passes through the shielding cover, and the copper busbar and the shielding cover maintain a certain distance to ensure the injection molding thickness, and the two need to be placed in the center.

[0033] In an IMC-HALL sensor, the shield's primary function is to provide a parallel magnetic field to the IMC-HALL sensor chip. In this solution, the shield not only provides a parallel magnetic field to the IMC-HALL sensor chip but also eliminates magnetic field interference for the differential Hall sensor chip, effectively reducing magnetic field interference from the power module or the application environment.

[0034] The detection copper busbar is connected to the motor by the power module. In order to ensure the compatibility of the IMC-HALL sensor chip detection solution and the differential Hall solution, a hole needs to be opened in the center of the shielding cover.

[0035] In terms of implementation, in order to realize the magnetic field strength detection of parallel magnetic field, the IMC-HALL sensor chip is fixed on the PCB board in the form of a patch. The chip is located directly above the center of the copper busbar opening and maintains a certain distance from the copper busbar.

[0036] Among them, the differential Hall chip is fixed on the PCB board in the form of a jack. It is necessary to ensure that the two Hall sensing elements of the chip are on the center line of the above-mentioned copper busbar opening. At the same time, the height of the two Hall sensing elements needs to be determined according to the magnetic field intensity sensing range of the Hall chip and the range of the differential output of the Hall chip.

[0037] Among them, Figure 5 and attached Figure 6Two PCB solutions are presented, differing primarily in the use of an IMC-HALL chip or a differential Hall effect chip. The PCB is secured to the injection-molded housing with self-tapping screws. The height of the PCB from the copper busbar needs to be adjusted based on the application to optimize the solution. The PCB is then connected to the signal adapter pins via soldering.

[0038] The beneficial effects of the present invention are: 1. The present invention provides a method for enhancing the anti-crosstalk capability of the differential Hall scheme and achieving compatibility between the differential Hall scheme and the IMC-Hall scheme at low cost.

[0039] 2. The present invention can enhance the anti-crosstalk capability of the differential Hall chip by adding a shielding cover around the chip, thereby ensuring its high-precision current detection capability in applications with small phase spacing.

[0040] 3. The present invention achieves the purpose of switching between two solutions by replacing only two different PCBs through the special design of the copper busbar and the shielding cover, thereby ensuring the feasibility and innovation of the solution.

[0041] It is worth mentioning that the technical features such as welding holes involved in the patent application of this invention should be regarded as prior art. The specific structure, working principle and possible control method and spatial layout method of these technical features can be selected by conventional means in the field and should not be regarded as the inventive point of this patent. This patent will not be further elaborated.

[0042] For those skilled in the art, it is still possible to modify the technical solutions described in the aforementioned embodiments, or to make equivalent replacements for some of the technical features therein. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A detection method for a current sensor compatible with IMC-HALL and differential Hall schemes, characterized in that: The current sensor is implemented by a current sensor compatible with IMC-HALL and differential Hall solutions. The current sensor compatible with IMC-HALL and differential Hall solutions includes an injection molded housing, a copper busbar unit, a circuit board, and a signal adapter pin. The copper busbar unit, the circuit board, and the signal adapter pin are all installed in the injection molded housing, wherein: The injection molded housing is provided with a circuit board mounting groove and a plurality of detection mounting channels, each of the detection mounting channels is provided with a U-shaped groove portion, an opening portion and a copper busbar mounting area, the U-shaped groove portion surrounds the opening portion and a shielding cover is mounted on the U-shaped groove portion, and the opening portion is located at the center of the shielding cover; The copper bar unit is provided with a plurality of detection copper bars, the number of the detection copper bars is consistent with the number of the copper bar installation areas, and the detection copper bars are installed one by one in the corresponding copper bar installation areas, and the positions of the detection copper bars surrounded by the corresponding shielding covers are provided with openings, and the opening portions are located in the openings; The circuit board is installed in the circuit board mounting slot and, depending on the detection requirements, the circuit board is an IMC-HALL circuit board or a differential Hall circuit board. Both the IMC-HALL circuit board and the differential Hall circuit board are provided with a plurality of chip mounting branches. The number of the chip mounting branches is consistent with the number of the detection copper bars and the chip mounting branches are located one by one in the middle of the corresponding shielding cover. The detection method is specifically implemented as follows: Step S1: When parallel magnetic field detection is required, the IMC-HALL circuit board is installed in the circuit board mounting slot. For the IMC-HALL circuit board, the IMC-HALL sensor chip is mounted on the side of the chip mounting branch close to the injection molded shell, and the IMC-HALL sensor chip is located directly above the center of the opening. The IMC-HALL sensor chip detects through a parallel magnetic field as follows: the current Ip generates a magnetic field B, which is converted into a parallel magnetic field B through the shielding cover. imc The IMC-HALL sensor core collects the parallel magnetic field B imc Convert it into B1 and B2, and output the difference between B1 and B2; Step S2: When differential magnetic field detection is required, the differential magnetic field detector is installed in the circuit board mounting slot. For the differential Hall circuit board, the side of the chip mounting branch close to the injection molded shell is plugged with a differential Hall chip and the differential Hall chip is built into the opening portion. The differential Hall chip performs detection through the differential magnetic field as follows: the current Ip generates a magnetic field B diff , the differential Hall chip detects the magnetic field B diff Magnetic field components B at different locations T and B B , and output the difference value.

2. The detection method of a current sensor compatible with IMC-HALL and differential Hall schemes according to claim 1, characterized in that: The size of the opening is determined by electromagnetic simulation.

3. The detection method of a current sensor compatible with IMC-HALL and differential Hall schemes according to claim 2, characterized in that: The height of the distance detection copper busbar on the circuit board is adjusted based on electromagnetic simulation and experimental test results to achieve the optimization of the two compatible solutions. The circuit board is equipped with a corresponding RC filtering circuit.

4. The detection method of a current sensor compatible with IMC-HALL and differential Hall schemes according to claim 3, characterized in that: The shielding cover and the corresponding detection copper busbar are integrated by injection molding. The size and shape of the shielding cover and the positional relationship between the shielding cover and the monitoring copper busbar are adjusted based on electromagnetic simulation.

5. The detection method of a current sensor compatible with IMC-HALL and differential Hall schemes according to claim 1, characterized in that: The circuit board is fixedly mounted in the circuit board mounting slot by self-tapping screws and is connected to the signal transfer pins by welding.

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