A magnetic angle sensor testing device

Abstract

The application provides a magnetic angle sensor testing device, which comprises a first substrate, a motor arranged on the first substrate, the motor comprising a motor body and a motor rotating shaft, and a magnetic field source for generating an external magnetic field, the magnetic field source being arranged on the first substrate and kept stationary during testing, wherein the magnetic angle sensor to be tested is fixed on the motor rotating shaft and opposite to the magnetic field source. Compared with the prior art, the magnetic field source is kept stationary, and the magnetic angle sensor to be tested is fixed on the motor rotating shaft. During testing, the motor drives the magnetic angle sensor to be tested to rotate, the rotation angle is taken as a reference angle, and the performance parameters of the sensor are calibrated according to the output of the sensor, so that the system error caused by the geomagnetic field can be avoided or eliminated, and the angle error caused by other constant weak magnetic field interference sources can also be eliminated, thereby improving the measurement accuracy of the rotation angle test of the magnetic angle sensor.

Description

[0001] The present application belongs to the field of sensor testing, and particularly relates to a high-precision simple magnetic angle sensor testing device.

[0002] At present, in addition to automatic testing systems, simple testing devices generally adopt the mode of rotating a permanent magnet by a motor while fixing a sensor for measuring. The mode of rotating a permanent magnet has the problem of inconsistency between the reference angle of motor rotation and the actual magnetic field direction rotation angle due to the existence of the geomagnetic field or other constant weak magnetic field interference sources, thereby resulting in systematic angle error. If a magnetic shielding device is added, considering that the required external magnetic field for measuring the magnetic angle sensor is large, and the magnetic shielding material itself is a high magnetic permeability material, it is easy to be magnetized, so a large amount of magnetic shielding material is needed to make a magnetic shielding device with a large volume, resulting in high cost. For high-precision magnetic angle sensors, such measurement is very unfavorable for accurate parameter calibration.

[0003] Therefore, it is necessary to provide a technical scheme to solve the systematic error caused by the above-mentioned measurement mode.

[0004] One of the purposes of the present application is to provide a magnetic angle sensor testing device which can not only avoid or eliminate the systematic error brought about (or generated) by the geomagnetic field, but also eliminate the angle error possibly brought about by other constant weak magnetic field interference sources, thereby realizing high-precision measurement.

[0005] According to one aspect of the present application, the present application provides a magnetic angle sensor testing device, comprising: a first substrate; a motor arranged on the first substrate, the motor comprising a motor body and a motor rotating shaft; a magnetic field source for generating an external magnetic field, the magnetic field source being arranged on the first substrate and remaining stationary during testing; wherein a to-be-tested magnetic angle sensor is fixed on the motor rotating shaft of the motor and opposite to the magnetic field source.

[0006] Further, the to-be-tested magnetic angle sensor is a magnetic angle sensor chip, and a sensing plane of the to-be-tested magnetic angle sensor is a surface of the magnetic angle sensor chip.

[0007] Further, the center of the motor rotating shaft, the center of the magnetic field source and the center of the to-be-tested magnetic angle sensor are located on the same coaxial line.

[0008] Further, the magnetization direction of the magnetic field source is perpendicular to the coaxial line; and / or the external magnetic field generated by the magnetic field source at the to-be-tested magnetic angle sensor is parallel to the sensing plane of the to-be-tested magnetic angle sensor.

[0009] ​​​Further, the magnetic angle sensor testing device further comprises a connecting component, the magnetic angle sensor to be tested and the motor rotating shaft are kept a certain distance, and the magnetic angle sensor to be tested is fixed on the motor rotating shaft through the connecting component.

[0010] Further, the connecting component adopts a non-magnetic material; and / or the test seat or printed circuit board loaded with the magnetic angle sensor to be tested and the connecting line adopt a non-magnetic material.

[0011] Further, the magnetic field source is a permanent magnet, the shape of the permanent magnet is a cylindrical magnet or a cuboid magnet, the magnetization direction of the cylindrical magnet is along the diameter direction thereof; and the magnetization direction of the cuboid magnet is along any side direction thereof.

[0012] Further, the magnetic field source is a double-magnet of a Helmholtz coil type, and the double-magnet of the Helmholtz coil type is equivalent to a Helmholtz coil with a fixed current.

[0013] Further, the double-magnet of the Helmholtz coil type comprises a first permanent magnet unit and a second permanent magnet unit arranged oppositely and at intervals, the adjacent faces of the first permanent magnet unit and the second permanent magnet unit are respectively an N-pole and an S-pole; and the spatial magnetic field of the double-magnet of the Helmholtz coil type is directed from the N-pole to the S-pole.

[0014] Further, the first permanent magnet unit and the second permanent magnet unit are both disc-shaped permanent magnet units, the radius of the disc-shaped permanent magnet unit is R, and the magnetization direction thereof is the thickness direction thereof; and the center distance of the first permanent magnet unit and the second permanent magnet unit is equal to the radius R of the disc-shaped permanent magnet unit.

[0015] Further, the first permanent magnet unit and the second permanent magnet unit are both square permanent magnet units or rectangular permanent magnet units, and the magnetization direction of the square permanent magnet unit and the rectangular permanent magnet unit is along the thickness direction thereof.

[0016] Further, the magnetic angle sensor testing device further comprises a first lifting platform and a second lifting platform arranged on the first base plate, the motor is placed on the first lifting platform and along the plane of the base plate; and the magnetic field source is placed on the second lifting platform.

[0017] Further, the magnetic angle sensor testing device further comprises a first lifting platform, a second lifting platform and a second base plate, the motor is placed vertically to the plane of the base plate; the first lifting platform and the second lifting platform are placed on the first base plate and are respectively located on the two sides of the motor; the second base plate is located on the first lifting platform and the second lifting platform and above the motor rotating shaft; and the magnetic field source is arranged on the second base plate.

[0018] Further, the magnetic angle sensor testing device further comprises a servo controller for controlling the motor shaft to rotate to a predetermined rotation angle; and a signal processing circuit for collecting the angle signal outputted by the to-be-tested magnetic angle sensor after the motor shaft rotates to the predetermined rotation angle, and detecting the performance parameter of the to-be-tested magnetic angle sensor by taking the predetermined rotation angle as a reference angle and combining the angle signal outputted by the to-be-tested magnetic angle sensor.

[0019] Compared with the prior art, in the magnetic angle sensor testing device, the magnetic field source is fixed, and the to-be-tested magnetic angle sensor is fixed on the motor shaft. During the testing process, the motor drives the to-be-tested magnetic angle sensor to rotate, and the rotation angle is taken as a reference angle to calibrate the performance parameter of the sensor according to the output of the sensor, so that the system error caused by the geomagnetic field can be avoided or reduced, and the angle error caused by other constant weak magnetic field interference sources can also be eliminated, thereby improving the measurement accuracy of the rotation angle testing of the magnetic angle sensor. BRIEF DESCRIPTION OF DRAWINGS

[0020] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor. Among them:

[0021] Figure 1 (a) is a vector analysis schematic diagram of the error caused by the geomagnetic field when the magnetic angle sensor is measured by using a rotating magnet;

[0022] Figure 1 (b) is a curve of the angle error changing with the reference angle when different working magnetic fields H are applied in the way of using a rotating magnet;

[0023] Figure 2 is a structural schematic diagram of a high-precision simple magnetic angle sensor testing device in an embodiment of the present application;

[0024] Figure 3 is a structural schematic diagram of a high-precision simple magnetic angle sensor testing device in another embodiment of the present application;

[0025] Figure 4 is a magnetic field distribution schematic diagram of a cylindrical and cuboid permanent magnet in the present application;

[0026] Figure 5 is a structural schematic diagram of a double-magnet of a Helmholtz coil type in an embodiment of the present application.

DETAILED DESCRIPTION

[0027] In order to make the above objectives, features and advantages of the present application more obvious and comprehensible, the present application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0028] The term "one embodiment" or "an embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with the implementation can be included in at least one implementation of the present application. The appearances of the phrase "in one embodiment" or "in an embodiment" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. The terms connected, coupled, or in communication, unless otherwise described, mean a direct or indirect connection.

[0029] Reference is made to Figure 1 (a) is a vector analysis diagram for measuring the error introduced by the geomagnetic field to the magnetic angle sensor using a rotating magnet (or magnetic field source), wherein the working magnetic field (or external magnetic field) generated by the magnet 101 is H, the component of the geomagnetic field is Hg, if the geomagnetic field is not considered, the angle of the working magnetic field H at this time is θ1, if the geomagnetic field is considered, the angle of the resultant field (or actual magnetic field) vector and direction is θ2, which makes the reference angle inconsistent with the actual magnetic field rotation angle, thereby causing the angle error △θ = θ1- θ2, and the angle error △θ varies with the rotation angle θ1. Wherein, △θ = arctan(Hgcosθ1 / (H-Hgsinθ1)). Assuming that the component of the geomagnetic field at this place is Hg = -0.37 Gs, the angle error △θ caused by the geomagnetic field varies with the reference angle (i.e. the rotation angle of the motor shaft) θ1 under the condition of applying different working magnetic fields H, as shown in Figure 1 (b). Figure 1 (b) shows that: when the working magnetic field H is constant, the variation curve of the angle error △θ with the rotation angle θ1 of the motor shaft has a 360-degree periodicity; the size of the angle error △θ is affected by the size and direction of the working magnetic field H, the smaller the working magnetic field H, the larger the angle error △θ; when the working magnetic field H is 300 Gs, the maximum angle error △θ caused by the geomagnetic field is 0.07 degrees; when the external magnetic field H is 200 Gs and 100 Gs, the maximum angle error △θ caused by the geomagnetic field can reach 0.1 and 0.2 degrees, which has a huge impact on high-precision magnetic angle sensors.

[0030] The geomagnetic field can be considered as constant in a certain area, and the magnetic field generated by the rotating magnet is superimposed with the geomagnetic field vector, resulting in that the actual magnetic field angle is inconsistent with the rotation angle. If the magnet is fixed, the vector sum of the magnetic field generated by the magnet and the geomagnetic field will remain unchanged, that is, the size and direction of the resultant magnetic field do not change, and the magnetic angle sensor to be measured can be rotated during measurement. In this way, the reference angle is based on the rotation angle of the magnetic angle sensor to be measured, and the inconsistency between the reference angle and the magnetic field angle will no longer exist, and high-precision measurement is achieved. Therefore, the application provides a magnetic angle sensor testing device which can avoid or eliminate the geomagnetic field error.

[0031] Please refer to Figure 2 Fig. 1 is a structural schematic diagram of a high-precision simple magnetic angle sensor testing device in an embodiment of the application. Figure 2 The magnetic angle sensor testing device shown in Fig. 1 comprises a first base plate (or a first water platform) 201, a first lifting platform 202a, a second lifting platform 202b, a motor 203, a connecting plate 205, a magnetic angle sensor to be measured 207 and a magnetic field source (or a magnet) 204.

[0032] The motor 203 is arranged on the first base plate 201 and comprises a motor body 203a and a motor rotating shaft 203b. In an embodiment, the motor 203 is controlled by a servo controller (not shown) to generate a precise rotation angle of the motor rotating shaft 203b, and the rotation angle of the motor rotating shaft 203b serves as a reference angle. In Figure 2 In the specific embodiment shown in Fig. 1, the motor 203 is placed horizontally on the first base plate 201.

[0033] The magnetic field source 204 is used to generate an additional magnetic field (or a working magnetic field) H, is arranged on the first base plate 201 and opposite to the end of the motor rotating shaft 203b, and remains stationary (or fixed) during testing. In Figure 2 In the embodiment shown in Fig. 1, the magnetic field source 204 is a permanent magnet, which can be made of neodymium iron boron, samarium cobalt or other materials such as ferrite.

[0034] The magnetic angle sensor to be measured 207 generates an angle signal representing a magnetic angle based on the magnetic field in the sensing plane. The magnetic angle sensor to be measured 207 is fixed on the end of the motor rotating shaft 203b of the motor 203 and rotates with the motor rotating shaft 203b. Moreover, the center (or axis, axis center) of the magnetic angle sensor to be measured 207 is coaxial with the center (or axis, axis center) of the magnetic field source 204 and the center (or axis, axis center) of the motor rotating shaft 203b, as shown in Figure 2to ensure that the magnetic angle sensor 207 under test experiences the uniformity of the magnetic field (or working magnetic field) H generated by the magnetic field source 204 during rotation, thereby reducing the angle error caused by the off-axis distance. In this embodiment, the magnetization direction of the magnetic field source 204 is perpendicular to the coaxial line 206.

[0035] It should be noted that, Figure 2 The magnetic angle sensor test device shown in the embodiment is made of non-magnetic materials, except for the motor 203 and the magnetic field source 204, including the test seat or PCB (Printed Circuit Board) on which the magnetic angle sensor 207 under test is loaded and the connecting wires (not shown). The magnetic angle sensor 207 under test cannot be directly fixed to the motor shaft 203b, because the motor shaft 203b is made of steel and has high magnetic permeability. In order to facilitate the fixation of other components, the motor shaft 203b generally has a notch on the shaft. If the motor shaft 203b is close to the magnetic field source, the magnetic field distribution of the magnetic field source (or magnet) 204 will be uneven. Therefore, the magnetic angle sensor 207 under test needs to be kept at a certain distance from the motor shaft 203b and fixed through the connecting component 205, which can be made of aluminum or other non-magnetic materials. Figure 2 In the specific embodiment shown in the figure, the connecting component 205 is a connecting plate, one end of which is fixed to the motor shaft 203b, and the other end is fixedly connected to the magnetic angle sensor 207 under test. Figure 2 In the embodiment shown in the figure, the magnetic angle sensor 207 under test is a magnetic angle sensor chip, and the sensing plane of the magnetic angle sensor 207 under test is the surface of the magnetic angle sensor chip. The external magnetic field generated by the magnetic field source 204 at the magnetic angle sensor 207 under test is parallel to the sensing plane of the magnetic angle sensor 207 under test.

[0036] The first lifting platform 202a and the second lifting platform 202b are placed on the first base plate (or first water platform) 201; the motor 203 is placed on the first lifting platform 202a, and the magnetic angle sensor 207 under test is fixed to the motor shaft 203b; the magnetic field source 204 is placed on the second lifting platform 202b and opposite to the magnetic angle sensor 207 under test. By adjusting the first lifting platform 202a and the second lifting platform 202b, the center (or axis, center) of the motor shaft 203b, the center (or axis, center) of the magnetic field source 204, and the center (or axis, center) of the magnetic angle sensor 207 under test can be kept coaxial, as shown in the coaxial line 206. Figure 2 In another embodiment, the lifting platforms 202a and 202b can also be fixed-height platforms, as long as the center of the motor shaft 203b, the center of the magnetic field source 204, and the center of the magnetic angle sensor 207 under test can be kept coaxial.

[0037] The size of the external magnetic field generated by the magnetic field source 204 at the magnetic angle sensor 207 under test is adjusted by the size, material selection of the magnetic field source 204 and the distance between the magnetic field source 204 and the magnetic angle sensor 207 under test. For example, the distance between the first lifting platform 202a and the second lifting platform 202b can be adjusted to change the size of the external magnetic field generated by the magnetic field source 204 at the magnetic angle sensor 207 under test.

[0038] Please refer to Figure 3 The figure is a structural schematic diagram of a high-precision simple magnetic angle sensor testing device in another embodiment of the present application. Figure 3 The magnetic angle sensor testing device shown in the figure includes a first base plate (or first water platform) 301, a first lifting platform 302a, a second lifting platform 302b, a motor 303, a connecting pipe 305, a magnetic angle sensor under test 307, a second base plate (or second water platform) 308 and a magnetic field source (or magnet) 304.

[0039] The motor 303 is arranged on the first base plate 301 and includes a motor body 303a and a motor rotating shaft 303b. In one embodiment, the motor 303 is controlled by a servo controller (not shown) to generate a precise rotation angle of the motor rotating shaft 303b, which serves as a reference angle. In Figure 3 In the specific embodiment shown in the figure, the motor 303 is placed vertically on the first base plate 301.

[0040] The magnetic field source 304 is used to generate an external magnetic field (or working magnetic field) H and is arranged on the first base plate 301 opposite the end of the motor rotating shaft 303b, and remains stationary during testing. In Figure 3 In the embodiment shown in the figure, the magnetic field source 304 is a permanent magnet, which can be made of neodymium iron boron, samarium cobalt or other materials such as ferrite. In Figure 3 In the embodiment shown in the figure, the magnetic field source 304 is located above the end of the motor rotating shaft 303b.

[0041] The magnetic angle sensor under test 307 generates an angle signal representing a magnetic angle based on the magnetic field in the sensing plane. The magnetic angle sensor under test 307 is fixed to the end of the motor rotating shaft 303b of the motor 303 and rotates with the motor rotating shaft 303b. Moreover, the center (or axis, axis) of the magnetic angle sensor under test 307 is coaxial with the center (or axis, axis) of the magnetic field source 304 and the center (or axis, axis) of the motor rotating shaft 303b, as shown in Figure 3to ensure that the to-be-tested magnetic angle sensor 307 can sense the uniformity of the magnetic field (or working magnetic field) H generated by the magnetic field source 304 during rotation, thereby reducing the angle error caused by the off-axis distance. In this embodiment, the magnetization direction of the magnetic field source 304 is perpendicular to the coaxial axis 306.

[0042] It should be noted that, Figure 3 The magnetic angle sensor test device shown in the figure is made of non-magnetic materials, except for the motor 303 and the magnetic field source 304, including the test seat or PCB (Printed Circuit Board) on which the to-be-tested magnetic angle sensor 307 is loaded and the connecting wires (not shown). The to-be-tested magnetic angle sensor 307 cannot be directly fixed on the motor shaft 303b, because the motor shaft 303b is made of steel and has high magnetic permeability. In order to facilitate the fixation of other components, the motor shaft 303b generally has a notch on the shaft. If the to-be-tested magnetic angle sensor 307 is too close to the magnetic field source (or magnet) 304, the magnetic field distribution of the magnetic field source 304 will be uneven. Therefore, the to-be-tested magnetic angle sensor 307 needs to be kept at a certain distance from the motor shaft 303b and be fixed through the connecting component 305, which can be made of aluminum or other non-magnetic materials. Figure 3 In the specific embodiment shown in the figure, the connecting component 305 is a connecting pipe, one end of which is sleeved on the end of the motor shaft 303b, and the other end is fixedly connected with the to-be-tested magnetic angle sensor 307. Figure 3 In the embodiment shown in the figure, the to-be-tested magnetic angle sensor 307 is a magnetic angle sensor chip, and the sensing plane of the to-be-tested magnetic angle sensor 307 is the surface of the magnetic angle sensor chip. The external magnetic field generated by the magnetic field source 304 at the to-be-tested magnetic angle sensor 307 is parallel to the sensing plane of the to-be-tested magnetic angle sensor 307.

[0043] The first lifting platform 302a and the second lifting platform 302b are placed on the first base plate (or first water platform) 301 and located on the two sides of the motor 303. The second base plate (or second water platform) 308 is placed on the first lifting platform 302a and the second lifting platform 302b and located above the motor 303. The to-be-tested magnetic angle sensor 307 is fixed on the end of the motor shaft 303b. The magnetic field source 304 is placed on the second base plate (or second water platform) 308 and opposite to the to-be-tested magnetic angle sensor 307. During the test, the to-be-tested magnetic angle sensor 307 and the magnetic field source 304 are kept at a certain distance, and the center (or axis, center) of the motor shaft 303b, the center (or axis, center) of the magnetic field source 304 and the center (or axis, center) of the to-be-tested magnetic angle sensor 307 are kept coaxial, as shown in the coaxial line 306. Figure 4 The coaxial line 306 shown in the figure.

[0044] The size of the external magnetic field generated by the magnetic field source 304 at the magnetic angle sensor 307 to be tested is adjusted by the size, material selection and distance of the magnetic field source 304 to the magnetic angle sensor 307 to be tested. For example, the size of the external magnetic field generated by the magnetic field source 304 at the magnetic angle sensor 307 to be tested can be changed by adjusting the height of the first lifting platform 302a and the second lifting platform 302b.

[0045] The magnetic angle sensor testing device in the present application further comprises a servo controller (not shown) and a signal acquisition circuit (or a signal processing circuit) (not shown). The specific testing method is that the servo controller controls the motor shaft 203b, 303b of the motor 203, 303 to rotate to a predetermined rotation angle; when the motor shaft 203b, 303b rotates to the predetermined rotation angle, the signal acquisition circuit acquires the angle signal output by the magnetic angle sensor to be tested, and takes the predetermined rotation angle of the motor shaft (which is equal to the rotation angle of the magnetic angle sensor to be tested) as the reference angle, and detects the performance parameters of the magnetic angle sensor to be tested in combination with the angle signal output by the magnetic angle sensor to be tested. In this way, the reference angle is based on the rotation angle of the magnetic angle sensor to be tested, and the situation that the reference angle is inconsistent with the actual rotation angle of the magnetic field direction no longer exists, so that not only can the system error caused by the geomagnetic field be avoided or reduced, but also the angle error caused by other constant weak magnetic field interference sources can be eliminated, thereby improving the measurement accuracy of the rotation angle test of the magnetic angle sensor.

[0046] Please refer to Figure 4 The shape of the permanent magnet 204, 304 in the present application can be a cylinder or a cuboid. Among them, the cylindrical permanent magnet is as shown in 400a of Figure 4 , and the cuboid permanent magnet is as shown in 400b of Figure 4 . For the convenience of description, in Figure 5A rectangular coordinate system is defined, in which the x-axis extends from left to right, and the y-axis extends from bottom to top. In 400a, the magnetization direction of the cylindrical permanent magnet is along its diameter direction, and is perpendicular to the magnet axis 402a (and perpendicular to the system co-axial line 206 and 306); at a certain distance from the surface of the cylindrical permanent magnet, the magnetic induction line distribution is shown by the dotted line 401a; the required working magnetic field direction is that the center line of the N-pole pointing to the S-pole is along the x direction, and if deviating from the center of the cylindrical permanent magnet, a component magnetic field in the y direction will be generated, introducing an off-axis error, therefore, the co-axiality of the center of the magnetic field source 204, 304 and the center of the magnetic angle sensor 207, 307 to be measured during the measurement is also very important. In 400b, the magnetization direction of the cuboid permanent magnet is along any edge direction thereof, and is perpendicular to the magnet axis 402b (and perpendicular to the system co-axial line 206 and 306); at a certain distance from the surface of the cuboid permanent magnet, the magnetic induction line distribution is shown by the dotted line 401b; the required working magnetic field direction is that the center line of the N-pole pointing to the S-pole is along the x direction, and if deviating from the center of the cuboid permanent magnet, a component magnetic field in the y direction will be generated, introducing an off-axis error.

[0047] The permanent magnet 204, 304 in the present application can also be a Helmholtz coil type double magnet, which is equivalent to a Helmholtz coil with a fixed current. Please refer to Figure 5 , which is a structure schematic diagram of the Helmholtz coil type double magnet in an embodiment of the present application. Figure 5 The Helmholtz coil type double magnet shown in Figure 5 includes oppositely and spacedly arranged first permanent magnet unit 510 and second permanent magnet unit 520; the first permanent magnet unit 510 and the second permanent magnet unit 520 are placed in parallel to the axis 530 (and 530 is parallel to the co-axial line 206 and 306, wherein the co-axial line 206 and 306 pass through the center of 500b, and are perpendicular to the paper); the adjacent faces of the first permanent magnet unit 510 and the second permanent magnet unit 520 are respectively N-pole and S-pole, and the spatial magnetic field points from the N-pole to the S-pole and is perpendicular to the axis 530, wherein the magnetic field uniformity in the central region is very high, please refer to Figure 5 in 500b. Figure 5 In the specific embodiment shown in ​ , the first permanent magnet unit 510 and the second permanent magnet unit 520 are both disc-shaped permanent magnet units shown in 500a, and the radius thereof is R, and the magnetization direction thereof is axial magnetization (or the magnetization direction thereof is along the axial direction of the disc-shaped permanent magnet unit, i.e. the thickness direction); the center distance d of the first permanent magnet unit 510 and the second permanent magnet unit 520 is equal to the radius R of the disc-shaped permanent magnet unit, please refer to

[0048] The double-magnet of the Helmholtz coil type in the application can also be composed of two square or rectangular permanent magnet units magnetized along the thickness direction. That is, the first permanent magnet unit 510 and the second permanent magnet unit 520 can be square permanent magnet units or rectangular permanent magnet units, and the magnetization direction of the square permanent magnet units and the rectangular permanent magnet units is along the thickness direction. Compared with a single cylinder or cuboid magnet, the Helmholtz coil magnet can provide a more uniform magnetic field, can reduce the off-axis error, and can further improve the test accuracy of the device.

[0049] In summary, the magnetic angle sensor testing device in the application comprises a first substrate 201, 301, a motor 203, 303 arranged on the first substrate 201, 301, the motor 203, 303 comprising a motor body 203a, 303a and a motor rotating shaft 203b, 303b, and a magnetic field source 204, 304 for generating an external magnetic field, the magnetic field source 204, 304 being arranged on the first substrate 201, 301 and remaining stationary during testing. Wherein, the magnetic angle sensor to be tested 207, 307 is fixed on the motor rotating shaft 203b, 303b and opposite to the magnetic field source 204, 304. In this way, the reference angle is based on the rotation angle of the magnetic angle sensor to be tested, and the situation that the reference angle is inconsistent with the actual magnetic field direction rotation angle will not exist, so as to not only avoid or reduce the system error caused by the geomagnetic field, but also eliminate the angle error caused by other constant weak magnetic field interference sources, and further improve the measurement accuracy of the rotation angle test of the magnetic angle sensor.

[0050] In the application, the words such as "connection", "connection", "connection", "connection" and the like represent the words connected, and if not specially stated, it represents direct or indirect connection.

[0051] The above is only the preferred embodiment of the application, and the protection scope of the application is not limited to the above-mentioned embodiment, but any equivalent modification or change made by the ordinary skilled in the art according to the disclosure content of the application shall be included in the protection scope recorded in the claims.

Claims

1. A magnetic angle sensor testing device, characterized in that It comprises: a first substrate; a motor disposed on the first substrate, the motor comprising a motor body and a motor shaft; a magnetic field source for generating an external magnetic field, the magnetic field source being disposed on the first substrate and remaining stationary during testing; a servo controller for controlling the motor shaft to rotate to a predetermined rotation angle; a signal processing circuit for collecting an angle signal output by a magnetic angle sensor under test after the motor shaft rotates to the predetermined rotation angle, and detecting a performance parameter of the magnetic angle sensor under test in combination with the angle signal output by the magnetic angle sensor under test and taking the predetermined rotation angle as a reference angle; wherein the magnetic angle sensor under test is fixed to the motor shaft of the motor and opposite the magnetic field source, and the motor shaft drives the magnetic angle sensor under test to rotate during testing, the center of the motor shaft, the center of the magnetic field source, and the center of the magnetic angle sensor under test are located on the same coaxial line, the magnetization direction of the magnetic field source is perpendicular to the coaxial line; and / or the external magnetic field generated by the magnetic field source at the magnetic angle sensor under test is parallel to the sensing plane of the magnetic angle sensor under test.

2. The magnetic angle sensor testing device according to claim 1, wherein the magnetic angle sensor under test is a magnetic angle sensor chip, the sensing plane of the magnetic angle sensor under test is the surface of the magnetic angle sensor chip.

3. The magnetic angle sensor test device of claim 1, wherein, It further comprises a connecting component, the magnetic angle sensor under test and the motor shaft are kept at a certain distance, and the magnetic angle sensor under test is fixed to the motor shaft through the connecting component.

4. The magnetic angle sensor testing device according to claim 3, wherein the connecting component is made of a non-magnetic material; and / or the test seat or printed circuit board carrying the magnetic angle sensor under test and the connecting line are made of a non-magnetic material.

5. The magnetic angle sensor testing device according to claim 1, wherein the magnetic field source is a permanent magnet, and the permanent magnet is in the shape of a cylindrical magnet or a cuboid magnet, the magnetization direction of the cylindrical magnet is along the diameter direction thereof, the magnetization direction of the cuboid magnet is along any edge direction thereof.

6. The magnetic angle sensor testing device according to claim 1, wherein the magnetic field source is a double-magnet of a quasi-Helmholtz coil, and the double-magnet of the quasi-Helmholtz coil is equivalent to a Helmholtz coil with a fixed current.

7. The magnetic angle sensor testing device according to claim 6, wherein the double-magnet of the quasi-Helmholtz coil comprises a first permanent magnet unit and a second permanent magnet unit disposed opposite and spaced apart, the adjacent faces of the first permanent magnet unit and the second permanent magnet unit are respectively an N-pole and an S-pole, the spatial magnetic field direction of the double-magnet of the quasi-Helmholtz coil is that the N-pole points to the S-pole.

8. The magnetic angle sensor testing device according to claim 7, wherein the first permanent magnet unit and the second permanent magnet unit are both disc-shaped permanent magnet units, and the radius thereof is R, and the magnetization direction thereof is the thickness direction thereof. The center distance of the first and second permanent magnet units is equal to the radius R of the disc-shaped permanent magnet unit.

9. The magnetic angle sensor testing device of claim 7, wherein, The first and second permanent magnet units are square or rectangular permanent magnet units, and the magnetization direction of the square or rectangular permanent magnet units is along the thickness direction thereof.

10. The magnetic angle sensor test device of claim 1, wherein, It further comprises a first lifting platform and a second lifting platform disposed on the first substrate, The motor is disposed on the first lifting platform and along the plane of the substrate; The magnetic field source is disposed on the second lifting platform.

11. The magnetic angle sensor testing device of claim 1, wherein, It further comprises a first lifting platform, a second lifting platform and a second substrate, The motor is disposed perpendicular to the plane of the substrate; The first and second lifting platforms are disposed on the first substrate and are respectively located on the two sides of the motor; The second substrate is located on the first and second lifting platforms and above the rotation axis of the motor; The magnetic field source is disposed on the second substrate.

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