Magnetoresistive angle sensor system and vehicle including the same

Abstract

Embodiments of the present disclosure relate to a magnetoresistive angle sensor system and a vehicle including the magnetoresistive angle sensor system. A magnetoresistive MR angle sensor system is used to measure the rotation angle of a rotating component in an out-of-axis (OOS) configuration. The MR angle sensor system includes a magnet attached to the rotating component. The MR angle sensor system also includes a magnetoresistive MR sensor. A sensitive plane of the MR sensor is positioned at a certain offset relative to the center of the magnet in an offset direction.

Description

Technical Field

[0001] Examples relate to a magnetoresistive angle sensor system and a vehicle including the magnetoresistive angle sensor system. Background Art

[0002] Magnetoresistive (MR) angle sensor systems have a wide range of possible applications. MR angle sensor systems are used in automotive applications, for example. Their areas of use range from steering angle applications with the highest functional safety requirements to motors for wipers, pumps and actuators and electric motors in general. They can also be used in industrial and consumer applications such as robotics or gimbals.

[0003] MR angle sensor systems are based on integrated magnetoresistance technology. Magnetoresistance is the tendency of a material to change its resistance value in an applied magnetic field. There are a variety of effects that can be called magnetoresistance, such as AMR, anisotropic magnetoresistance; GMR, giant magnetoresistance; and tunnel magnetoresistance TMR. MR angle sensor systems measure the rotation angle of a rotating part. MR angle sensor systems include MR sensors, MR sensors detect the rotation angle of a rotating part to which a magnet is attached by measuring the sine and cosine components of the magnetic field generated by the magnet. Measuring magnetoresistance when the magnet is attached to a rotating part in an end-of-axis EOS configuration is typically used to detect the rotation angle. In the EOS configuration, the magnet is attached to the end of the shaft of the rotating part and the MR sensor is arranged near the end of the shaft of the rotating part. In some applications, the EOS configuration cannot be used, for example, due to geometric restrictions on the arrangement of the components used. Another possibility is to measure the magnetoresistance of an off-axis OOS configuration. In the OOS configuration, the magnet can be arranged at the peripheral surface of the rotating part and the MR sensor is arranged near the magnet. Since the setup is no longer symmetrical, measuring in this OOS configuration may result in reduced measurement accuracy. While some applications may require an OOS configuration for geometric reasons, the reduced accuracy of a conventional OOS configuration may prohibit the use of an OOS configuration. Summary of the invention

[0004] Therefore, there is a need to provide a more accurate method to measure the rotation angle of a rotating component in an OOS configuration, which is suitable for many applications.

[0005] This need is solved by the subject matter of the independent claims.

[0006] One example relates to a magnetoresistive MR angle sensor system for measuring the rotation angle of a rotating component in an out-of-axis OOS configuration. The MR angle sensor system includes a magnet attached to the rotating component, and a magnetoresistive sensor. The sensitive plane of the MR sensor is positioned with a certain offset relative to the center of the magnet in an offset direction. By positioning the sensitive plane of the MR sensor to have a certain offset relative to the center of the magnet in the offset direction, the measurement accuracy of the rotation angle of the rotating component can be improved. The offset can determine the relationship between the magnetic field components in the first direction and the second direction used to determine the rotation angle. Due to the offset, the difference between the magnetic field components in the first direction and the second direction can be reduced, so that the rotation angle can be determined with high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Some examples of the system will be described below by way of example only and with reference to the accompanying drawings, in which

[0008] Figure 1a A conventional magnetoresistive MR angle sensor system in an end-of-shaft configuration and the dependence of magnetic field components in a first direction and a second direction on the rotation angle are shown;

[0009] Figure 1b A conventional MR angle sensor system in an out-of-axis (OOS) configuration and the dependence of magnetic field components in a first direction and a second direction on the rotation angle are shown;

[0010] Figure 1c A conventional MR angle sensor system of an OOS configuration in which the MR sensor and the magnet are arranged in parallel and the dependence of the magnetic field components in the first direction and the second direction on the rotation angle are shown;

[0011] Figure 1d shows the dependence of the error of the rotation angle measured in a conventional system on the mechanical angle;

[0012] Figure 2a An MR angle sensor system of an OOS configuration according to a first embodiment of the present disclosure and dependence of magnetic field components in a first direction, a second direction, and a third direction on a rotation angle are shown;

[0013] Figure 2b A three-dimensional representation of magnetic field components in a first direction and a second direction and a two-dimensional representation of magnetic field components in an embodiment of the present disclosure are shown;

[0014] Figure 2c A three-dimensional representation of the magnetic field components and a two-dimensional representation of the magnetic field components for different offsets are shown;

[0015] Figure 2d shows the dependence of the ratio of the amplitudes of the magnetic field components in the first direction and the second direction on the offset;

[0016] Figure 3a An MR angle sensor system of an OOS configuration according to a second embodiment of the present disclosure and a magnet of the MR angle sensor system according to the second embodiment are shown;

[0017] Figure 3b The dependence of the ratio of the amplitudes of the magnetic field components in the first direction and the second direction on the offset and the dependence of the magnetic field components on the rotation angle are shown;

[0018] Figure 3c A three-dimensional representation of magnetic field components in a first direction and a second direction and a two-dimensional representation of magnetic field components are shown;

[0019] Figure 3d shows the dependence of the magnetic angle of the OOS configuration on the mechanical angle and the dependence of the magnetic angle error of the OOS configuration on the mechanical angle; and

[0020] Figure 4 A portion of a vehicle including an MR angle sensor system in an OOS configuration in a shift-by-wire (SBW) application according to a third embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0021] Some examples are now described in more detail with reference to the accompanying drawings. However, other possible examples are not limited to the features of these embodiments described in detail. Other examples may include modifications of features and equivalents and alternatives of features. In addition, the terms used to describe some examples herein should not limit other possible examples.

[0022] Throughout the description of the drawings, the same or similar reference numerals refer to the same or similar elements and / or features, which may be implemented in the same or modified form while providing the same or similar functions. The thickness of lines, layers and / or regions in the drawings may also be exaggerated for clarification.

[0023] When two elements A and B are combined using "or", this should be understood to disclose all possible combinations, i.e. only A, only B and A and B, unless otherwise explicitly defined in individual cases. As alternative wording for the same combination, "at least one of A and B" or "A and / or B" can be used. The same applies to combinations of more than two elements.

[0024] If singular forms such as "a", "an" and "the" are used, and the use of only a single element is not explicitly or implicitly defined as mandatory, other examples may also use multiple elements to implement the same functionality. If a function is described below as being implemented using multiple elements, other examples may use a single element or a single processing entity to implement the same functionality. It should also be understood that the terms "include", "including", "comprises" and / or "comprising" when used describe the presence of specific features, wholes, steps, operations, processes, elements, components and / or groups thereof, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, processes, elements, components and / or groups thereof.

[0025] Figure 1a A conventional magnetoresistive angle sensor system 100a of an end of shaft EOS configuration is shown in the left figure. The MR angle sensor system 100a includes a magnet 101a that may be disk-shaped. The magnet 101a is attached to a rotating component 102a. The rotating component 102a may have a cylindrical shape. The rotating component 102a may have an axis extending in its longitudinal direction, which is parallel to the rotation axis R of the rotating component 102a. In the EOS configuration, the magnet 101a is arranged at the end of the shaft of the rotating component 102a. The MR angle sensor system 100a also includes a magnetoresistive MR sensor 103a for measuring the rotation angle of the rotating component 102a. The MR sensor is sensitive to a magnetic field component Bx in at least a first direction x and a magnetic field component By in at least a second direction y perpendicular to the first direction x. The sensitive plane of the MR sensor 103a is formed by the first direction x and the second direction y. The rotation axis R may be perpendicular to the sensitive plane. The sensitive plane of the MR sensor may be located in an EOS configuration below the end of the shaft of the rotating component 102a to which the magnet 101a is attached.

[0026] Figure 1a The right figure shows the dependence of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y on the rotation angle ra. Figure 1a The magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y shown in the right figure are Figure 1a The conventional MR angle sensor system 100a of the EOS configuration shown in the left figure is measured. The first direction x and the second direction y can be perpendicular to the third direction z, and the third direction z can be parallel to the axis of the rotating component 102a and the rotation axis R. Figure 1a It can be seen from the right figure that the amplitude of the magnetic field component Bx in the first direction x at least substantially corresponds to the amplitude of the magnetic field component By in the second direction y.

[0027] The rotation angle ra is calculated using a calibration method. The calibration method uses the magnetic field components Bx and By measured by the MR sensor 103a to calculate the rotation angle ra. The parameters that affect the angle calculation are the offset, amplitude, and non-orthogonality of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y. The offset is a constant, an addition or subtraction amount, or a systematic error of the measured value (in this case, the magnetic field component Bx in the first direction and the magnetic field component By in the second direction). Non-orthogonality is, for example, a phase difference between a magnetic field component in the first direction x with a cosine signal and a magnetic field component in the second direction y with a sine signal. The calibration method may include offset correction, amplitude normalization, and correction of non-orthogonality. The offset correction causes the amplitude of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y to shift relative to the ordinate by the amount of the above-mentioned offset. The amplitude normalization correction amplitude is such that the amplitude of the magnetic field component Bx in the first direction x and the amplitude of the magnetic field component By in the second direction y have at least substantially the same amount. The correction of the non-orthogonality corrects the phase shift of the magnetic field component Bx in a first direction x, for example with a cosine signal, and the magnetic field component By in a second direction y, for example with a sine signal, to at least substantially 90°.

[0028] Since the magnetic field components Bx, By of the EOS configuration are equal in magnitude, the rotation angle ra of the rotating component 102a measured using the calibration method may have low error, resulting in high accuracy in the measurement in the EOS configuration. Unfortunately, not all applications allow the MR angle sensor system 100a to measure the rotation angle of the EOS configuration.

[0029] Figure 1b The left figure shows a conventional MR angle sensor system 100b in an OOS configuration. The magnet 101b of the OOS configuration is connected to Figure 1a The difference between the magnet 101a in the MR angle sensor system 100a shown in the left figure is that the magnet 101b may be annular and arranged at the peripheral surface of the rotating component 102b. The MR sensor 103b is arranged near the magnet 101b.

[0030] exist Figure 1b The right figure of FIG. 1 shows the dependence of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y on the rotation angle ra of the rotating component 102b. Figure 1b As shown in the right figure of FIG. 1 , the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y are measured by a conventional MR angle sensor system 100b with an OOS configuration. Figure 1a Compared with the EOS configuration in the right figure, Figure 1bThe OOS configuration in the right figure of shows that the amplitude of the magnetic field component Bx in the first direction x is significantly different from the amplitude of the magnetic field component By in the second direction y. In this OOS configuration, one of the amplitudes of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y can become smaller than the other amplitude.

[0031] Figure 1c Another conventional MR angle sensor system 100c in an OOS configuration is shown in the left figure. Figure 1c The conventional MR angle sensor system 100c shown in the left figure is Figure 1b The difference of the conventional MR angle sensor system 100b shown in the left figure is that the sensitive plane of the MR sensor 103c and the PCB, printed circuit board, are arranged parallel to the magnet 101c. There is an air gap between the magnet 101c and the MR sensor 103c for the axis rotation of the rotating part 102c. In addition, Figure 1c The conventional MR angle sensor system 100c shown in the left figure at least substantially corresponds to Figure 1b A conventional MR angle sensor system 100b is shown in the left figure of FIG.

[0032] exist Figure 1c The right figure of FIG. 1 shows the dependence of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y on the rotation angle ra of the rotating member 102c. Figure 1c In the OOS configuration shown in the left figure of FIG. 1 , the magnetic field component By in the first direction x and the magnetic field component By in the second direction y are measured using a conventional MR angle sensor system 100 c. Figure 1a The EOS configuration in the right picture is the opposite. Figure 1c The OOS configuration in the right figure shows that the amplitude of the magnetic field component Bx in the first direction x is significantly different from the amplitude of the magnetic field component By in the second direction y, much like Figure 1b Implementation.

[0033] The calibration method used to calculate the rotation angle ra in the EOS configuration does not work properly in the OOS configuration because one of the magnetic field components Bx, By may become smaller than the other in the OOS configuration. If the amplitudes of the magnetic field components Bx, By have unequal magnitudes, the amplitude normalization used in the calibration method may result in a high error in the measured rotation angle ra. Due to this relationship of the amplitudes of the magnetic field components Bx, By, in the OOS configuration, low accuracy of the measurement of the rotation angle ra may be experienced.

[0034] Figure 1d The low accuracy of the measurement of the rotation angle ra in the OOS configuration is shown. Figure 1d The upper left figure shows the magnetic field components Bx, By and Bz for Figure 1c 1. The dependence of the rotation angle ra measured by the conventional MR angle sensor system 100c shown. The amplitudes of the magnetic field components Bx, By, and Bz are significantly different from each other. Typically, the MR angle sensor system operates in the saturation magnetic field region. Although conventional MR sensor calibration methods can compensate for the amplitude of the MR sensor output, offset, and orthogonality, if the amplitudes of the magnetic field components Bx, By, and Bz have unequal magnitudes, conventional amplitude normalization may result in a higher error in the measured rotation angle because the magnetic field sensor operates in the saturation magnetic field region. Therefore, conventional calibration methods may not be able to compensate for the amplitude of the MR sensor output, offset, and orthogonality. Figure 1c The MR angle sensor system shown operates normally because the sensor outputs of the magnetic field component Bx and the magnetic field component By may not be proportional to the applied B field amplitude in the saturation region.

[0035] Figure 1d The lower left figure shows the dependence of the mechanical angle Figure 1c Such distorted MR sensor outputs TMRx, TMRy of the conventional MR angle sensor system 100c are shown. The MR sensor outputs TMRx, TMRy are unequally distorted in the saturation region, resulting in unequal amplitudes of the magnetic field components Bx, By, thereby causing a large error in the measured rotation angle ra.

[0036] exist Figure 1d The upper right figure shows that when using Figure 1c The conventional MR angle sensor system 100c measures the dependence of the magnetic angle of the rotating component 102c on the mechanical angle. Figure 1c The dashed line 104 in the left figure of shows the theoretical dependence of the measured magnetic angle on the mechanical angle of the rotating component, which is, of course, linear. The magnetic angle or rotation angle defines the angle of the rotating component 102c, which is measured by the MR angle sensor system 100c. The mechanical angle defines the mechanical measured angle of the rotating component 102c. The solid line 105 shows the value measured using a conventional MR angle sensor system 100c. The difference between the dashed line 104 and the solid line 105 is the error in the measured rotation angle, which is large and is mainly caused by, for example, Figure 1d The distortion caused by the sensor output is shown in the lower left figure.

[0037] Figure 1d The lower right figure of shows the dependency of the error E of the measured rotation angle on the mechanical angle of the rotating component. Due to the shape of the distortion signal in the lower left figure, the error E is largest for mechanical angles 45°, 135°, 225° and 315°.

[0038] In summary, conventional MR sensor systems 100b, 100c have disadvantages in measuring rotation angles in an OOS configuration. Therefore, there is a need for an MR angle sensor system that allows high measurement accuracy in an OOS configuration.

[0039] This need is caused by Figure 2a The illustrated MR angle sensor system 200 satisfies this requirement. Figure 2a An MR angle sensor system 200 for measuring the rotation angle of a rotating component 202 of an OOS configuration according to a first embodiment of the present disclosure is shown. The rotating component 202 can be, for example, a cylindrical shaft. Alternatively, the rotating component 202 can have any shape required for a given application. For example, the rotating component 202 can have a rectangular parallelepiped, a cone, a truncated cone, a prism, a sphere, or a pyramid shape. In the illustrated embodiment, the rotating component 202 has a rotation axis R, which is parallel to the longitudinal direction of the rotating component 202.

[0040] The MR angle sensor system 200 includes a magnet 201 attached to a rotating component 202. The magnet 201 has an annular shape. In alternative embodiments, the magnet 201 can have any shape required for a given application. For example, the magnet 201 can have a ring or hollow cylindrical shape. The magnet 201 is arranged at the outer surface of the rotating component 202. The magnet 201 can have a depth of 2 mm. The poles of the magnet 201 can be configured to be pivotable around a rotation axis, for example. The direction between the poles of the magnet 201 can be substantially perpendicular to the rotation axis R. Thus, the rotation angle can be measured with high accuracy.

[0041] The MR angle sensor system 200 also includes an MR sensor 203. The MR sensor 203 may be one of an anisotropic magnetoresistive sensor, a giant magnetoresistive sensor, or a tunnel magnetoresistive sensor. The MR sensor 203 is configured to measure magnetic field components in a first direction x and a second direction y perpendicular to the first direction x. The first direction x and the second direction y form a sensitive plane of the MR sensor 203. The sensitive plane of the MR sensor 203 is positioned relative to the center of the magnet 201 at an offset 204 in the offset direction. Positioning the MR sensor 203 in such a manner with a non-zero offset may result in equal amplitudes of magnetic field components in the first direction x and the second direction y. Therefore, if the amplitudes of the magnetic field components in the first direction x and the second direction y are equal in magnitude, amplitude normalization in the calibration method is not necessary and may result in low errors in the measured rotation angle. Therefore, a higher accuracy of the calibration method and therefore a higher accuracy of the measured rotation angle of the OOS configuration may be achieved.

[0042] The offset direction is parallel to Figure 2aThe MR angle sensor system 200 is a rotation axis R of the rotating component 202 in the MR angle sensor system 200. Alternatively, the offset direction can be perpendicular to the rotation axis R of the rotating component 202. In both cases, the MR sensor 203 is capable of measuring the magnitude of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y. In these cases, an arrangement of the MR sensor 203 relative to the magnet 201 can be provided that allows the rotation angle of the rotating component 202 to be reliably measured with high accuracy.

[0043] The first direction x and the second direction y may be perpendicular to the direction between the poles of the magnet 201. Alternatively, the first direction x or the second direction y may be parallel to the direction between the poles of the magnet 201. These cases may provide options for defining a sensitive plane of the MR sensor 203 relative to the magnet 201 to measure the rotation angle with high accuracy.

[0044] Between the MR sensor 203 and the magnet 201 there may be an air gap present in a direction perpendicular to the deflection direction. The air gap may be, for example, at most 1 mm, at most 2 mm, at most 4 mm, at most 5 mm, at most 7 mm, or at most 10 mm. An air gap having these dimensions allows accurate measurement of the magnetic field components in the first direction x and the second direction y.

[0045] The MR angle sensor system 200 may further include a printed circuit board PCB. The MR sensor 203 may be arranged on the PCB.

[0046] The MR angle sensor system 200 may also include a circuit device configured to receive information about the magnetic field components measured by the MR sensor 203 and determine the direction of the magnet based on the information about the measured magnetic field components. The circuit device may include a processing circuit. The processing circuit may be configured to determine the rotation angle due to the magnetic field components in the first direction x and the second direction y. This may enable the rotation angle to be measured with high accuracy. The MR sensors 101c, 102c, 103c may be implemented as a single chip that is configured to determine the rotation angle based on the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y. Therefore, the calculations performed to derive the angle from the measured field components are performed within the chip that includes the magnetic field sensor.

[0047] Alternatively, the rotation angle can be determined by a separate circuit or chip. Such a separate circuit may include an interface for receiving the measured amplitude of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y from the MR sensors 101c, 102c, 103c. The separate circuit can be connected to the MR sensors 101c, 102c, 103c via the interface. In addition, the MR sensors 101c, 102c, 103c can be configured to determine the rotation angle based on the measured amplitude of the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y.

[0048] Figure 2a In the right picture, Figure 2b , 2c and 2d show the use of Figure 2a The MR angle sensor system 200 of the first embodiment shown in the left figure measures the magnetic field components Bx, By, and Bz.

[0049] Figure 2a The right figure shows the dependence of the magnetic field component Bx in the first direction x, the magnetic field component By in the second direction y, and the magnetic field component Bz in the third direction z on the rotation angle ra. Figure 2a The non-zero offset 204 between the MR sensor 203 and the center of the magnet 201 shown in the left figure can generate a non-zero magnetic field component Bx in the first direction x, a magnetic field component By in the second direction y, and a magnetic field component Bz in the third direction z. Therefore, the non-zero offset 204 between the MR sensor 203 and the center of the magnet 201 is selected so that the magnetic field component Bx in the first direction x and the magnetic field component By in the second direction y have at least substantially equal magnitudes. Therefore, a higher accuracy in measuring the rotation angle can be obtained.

[0050] Figure 2b The left picture is represented in three dimensions It is shown in Figure 2a The same parts as shown on the right. Figure 2b The left figure shows the magnetic field components in the first direction x, the second direction y and the third direction z. These magnetic field components are represented in this three-dimensional In addition, the two-dimensional trajectory of the magnetic field components in the first direction x and the second direction y like Figure 2b The trajectory is shown in the left figure. It may have an inclined elliptical shape. Three-dimensional trajectory of magnetic field components in the first direction x, the second direction y and the third direction z The tilted ellipse indicates that the magnetic field component within the sensitive plane formed by the first direction x and the second direction y has a non-zero offset 204 when the magnet 201 is fully rotated.

[0051] Figure 2b Another representation of the magnetic field components Bx, By, Bz is shown, which is used to enable an easy and reliable selection of a non-zero offset 204 of the MR sensor 203 such that the magnetic field components Bx, By have at least substantially equal magnitude. Figure 2b The figure on the right shows Figure 2b The top view of the inclined elliptical trajectory shown in the left figure. 2. The magnetic field components in the first direction x and the second direction y are shown in a two-dimensional representation. When the magnet 201 has a full rotation with a non-zero offset 204, the measurement Figure 2b The two-dimensional trajectory of the magnetic field components in the first direction x and the second direction y in and the three-dimensional trajectories of the magnetic field components in the first direction x, the second direction y, and the third direction z

[0052] Figure 2c The magnetic field components Bx, By, Bz are shown with different offsets 204 to achieve the goal of having at least substantially equal magnitudes of the magnetic field components Bx, By.

[0053] Figure 2c In the upper diagram a three-dimensional representation of the magnetic field components in the first direction x, the second direction y and the third direction z for different displacements is shown. Figure 2c The upper six plots in Figure 2b The representation in the left figure.

[0054] Figure 2c In the lower part a two-dimensional representation of the magnetic field components in the first direction x and the second direction y for different offsets 204 is shown Figure 2c In the lower part, the projected ellipsoids of the magnetic field components in the first direction x, the second direction y and the third direction z in the sensitive plane of the MR sensor 203 are shown for different shifts 204 to the magnetic field components in the first direction x and the second direction y. Figure 2c The following nine figures in Figure 2b The amount of inclination of the elliptical trajectory can be controlled by the offset 204. Therefore, the trajectory of the magnetic field component It can be a circle instead of an ellipse by having an appropriate offset 204 to determine the shape, as shown in Figure 2c below. For a circular trajectory with a magnetic field component The offset 204 is 1 mm, so that the magnetic field components Bx and By have at least substantially equal magnitudes. The trajectory of is a circle. Therefore, the circular trajectory This results in a high measurement accuracy of the rotation angle ra in the OOS configuration.

[0055] Figure 2d Another representation is shown which enables a user to select an offset 204 that satisfies the condition that the magnetic field components Bx, By have at least substantially equal magnitude. Figure 2d The left figure shows the dependence of the ratio dx / dy of the amplitudes of the magnetic field components in the first direction x and the second direction y on the offset 204. In the figure, the offset 204 that satisfies the condition that the amplitude of the magnetic field component in the first direction x at least substantially corresponds to the amplitude of the magnetic field component in the second direction y is marked as 10. If dx / dy is at least substantially 1, this condition is satisfied. The offset 204 can have a value of 0.91 mm, for example. The sensitive plane of the MR sensor 203 is positioned relative to the center of the magnet 201 in the offset direction with the offset 204. This arrangement of the MR sensor 203 relative to the magnet 201 with the offset 204 makes it possible to measure the rotation angle ra of the rotating part 202 while maintaining high accuracy as in the EOS configuration using the existing typical calibration method. The offset value that makes the ratio of the amplitudes of the magnetic field components in the first direction x and the second direction y at least substantially 1 always exists. The MR sensor 203 requires that the amplitude ratio for high-precision applications satisfies this condition.

[0056] Figure 2d The two-dimensional representation of the magnetic field components in the first direction x and the second direction y is shown in the figure on the right Figure 2d The representation in the right figure corresponds to Figure 2b The representation in the left figure and Figure 2c The lower half of the nine figures. Figure 2d The right figure of FIG. 2 shows the dependence of the magnetic field component in the first direction x on the magnetic field component in the second direction y at offset 204, which is Figure 2d and satisfies the condition that the amplitude of the magnetic field component in the first direction x at least substantially corresponds to the amplitude of the magnetic field component in the second direction y. At this offset, Figure 2d The right image has a circular shape.

[0057] Therefore, selecting a suitable offset in the OOS configuration is important for achieving high accuracy of the measured rotation angle ra. In the OOS configuration, a non-zero offset between the MR sensor 203 and the magnet 201 can be applied to sense non-zero magnetic field components in the first direction x and the second direction y. The MR sensor 203 is placed with a non-zero offset relative to the magnet 201, which makes the ratio of the amplitudes of the magnetic field components in the first direction x and the second direction y at least substantially equal to 1 for high-precision applications.

[0058] Alternatively, the offset may be selected so that the ratio of the amplitude of the magnetic field component in the first direction x to the amplitude of the magnetic field component in the second direction y is within one of the following ranges at the location of the MR sensor 203: 0.85 to 1.15; 0.9 to 1.1; or 0.95 to 1.05. In this case, high measurement accuracy of the MR sensor 203 may be achieved. The mapping calibration method may apply a non-ideal offset that may not make the ratio of the amplitude of the magnetic field component in the first direction x to the second direction y equal to 1. However, it must also have a non-zero offset.

[0059] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 2a The example shown in the left figure may include one or more optional additional features.

[0060] Figure 3a The left figure shows an MR angle sensor system 300 of an OOS configuration according to a second embodiment of the present disclosure for an OOS rotor position sensing application. Rotor position sensing is a system for accurately measuring the position of a rotor. The MR angle sensor system 300 according to the second embodiment is similar to the MR angle sensor system according to the embodiment. Figure 2a The difference of the MR angle sensor system 200 of the first embodiment shown in the left figure is that the magnet 301 is a ring magnet 301. Figure 3a The right figure of the MR angle sensor system 300 is shown as a ring. Therefore, the MR angle sensor system 300 according to the second embodiment is configured for rotor position sensing. The ring magnet 301 may have an inner diameter of 5 mm and / or an outer diameter of 10 mm. The magnet 301 may have a magnetic flux density of 1000 mT. Apart from this, the MR angle sensor system 300 according to the second embodiment corresponds to the MR angle sensor system 200 according to the first embodiment.

[0061] Figure 3b , 3c 3d show how to select a suitable offset for OOS rotor position sensing in the MR angle sensor system 300 . Figure 3b The left figure shows the dependence of the ratio dx / dy of the amplitudes of the magnetic field components Bx, By measured using the MR angle sensor system 300 according to the second embodiment on the offset 304. In the figure, the offset that satisfies the condition that the amplitude of the magnetic field component Bx in the first direction x at least substantially corresponds to the amplitude of the magnetic field component By in the second direction y is marked as 10. This condition is met if dx / dy is at least substantially 1. The offset 304 can have a value of 0.91 mm, for example.

[0062] Figure 3bThe right figure shows the dependence of the magnetic field components in the first direction x, the second direction y, and the third direction z on the rotation angle measured using the MR angle sensor system 300 according to the second embodiment. Figure 3b As shown in the right figure of FIG. 1 , the amplitude of the magnetic field component Bx in the first direction x corresponds at least substantially to the amplitude of the magnetic field component By in the second direction y. Therefore, the selected offset achieves the goal of the magnetic field components Bx, By having at least substantially equal magnitudes. This leads to a high measurement accuracy of the rotation angle ra in OOS rotor position sensing using the calibration method.

[0063] Figure 3c The left figure shows a three-dimensional representation of the magnetic field components in the first direction x, the second direction y and the third direction z measured using the MR angle sensor system 300 according to the second embodiment. Trajectory of the magnetic field components in three dimensions is oval, such as Figure 3c As shown in the left figure. Figure 3c The left figure also shows the trajectory of the magnetic field components in the first direction x and the second direction y. It is a circle. The trajectory is also Figure 3c The plane diagram in the right figure is represented in two dimensions Shown. Figure 3c The right figure shows the magnetic field components in the first direction x and the second direction y measured using the MR angle sensor system 300 according to the second embodiment. It is a circle. The circular trajectory It is shown that the magnetic field components Bx, By have at least substantially equal magnitude, resulting in a high measurement accuracy of the rotation angle ra in OOS rotor position sensing.

[0064] Figure 3d The measured rotation angle in OOS rotor position sensing is shown with an optimal offset 304. The optimal offset 304 achieves the goal of having magnetic field components Bx, By of at least substantially equal magnitude. Figure 3d The left figure shows the dependence of the magnetic angle or rotation angle on the mechanical angle 20 in an OOS configuration. The magnetic angle is measured using an MR angle sensor system 300 according to the second embodiment. Figure 3d As shown in the left figure of , the dependence between the magnetic angle and the mechanical angle 20 is linear and has no offset. Therefore, using this offset 304 can achieve a proper calibration.

[0065] Figure 3d The right figure shows the dependency of the error of the magnetic angle 30 measured using the MR angle sensor system 300 of the OOS configuration according to the second embodiment on the mechanical angle. Figure 3dAs can be seen from the right figure of FIG. 3 , the dependence of the magnetic angle error on the mechanical angle 30 is a polynomial with an optimal offset 304. Therefore, according to the simulation, only by performing appropriate offset 304 positioning, the MR sensor 303 can achieve high-precision rotation angle measurement in OOS rotor position sensing.

[0066] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 3a The example shown in the left figure may include one or more optional additional features.

[0067] Figure 4 A portion of an MR angle sensor system 400 including an OOS configuration for a vehicle in a shift-by-wire SBW application according to a third embodiment of the present disclosure is shown. Shift-by-wire is a system by which the transmission mode in a car can be changed by electronic control without any mechanical connection between the shift lever and the transmission. This can eliminate the wiring space required to accommodate the mechanical linkage between the shifter and the transmission, and can provide easy shifting by pressing a button or by a knob. Eliminating this connection can eliminate any shifting work from the driver selecting a gear. The MR angle sensor system 400 according to the third embodiment is different from the MR angle sensor systems 200 and 300 according to the first and second embodiments in that it is configured for SBW applications. In addition to this, the MR angle sensor system 400 according to the third embodiment also includes a rotating shaft forming a rotating component 402. The rotating shaft can be one of a camshaft, a crankshaft, a steering shaft, or a shaft of a human interface controller. Therefore, different rotating shafts suitable for different applications can be provided. The magnet 401 can be disc-shaped and arranged at the end of the rotating shaft 402. The rotation axis R of the rotating shaft can be parallel to the longitudinal direction of the rotating shaft. Apart from this, the MR angle sensor system 400 according to the third exemplary embodiment corresponds to the MR angle sensor system 200 according to the first exemplary embodiment.

[0068] Furthermore, the MR angle sensor system 400 needs to be offset to achieve the goal that the magnetic field components Bx, By have at least substantially equal magnitudes. This results in a high measurement accuracy of the rotation angle ra using the calibration method at OOS SBW.

[0069] Further details and aspects are mentioned in conjunction with the embodiments described above or below. Figure 4 The examples shown may include one or more optional additional features.

[0070] Aspects and features associated with a particular one of the previous examples may also be combined with one or more other examples to replace the same or similar features of that other example or otherwise introduce these features into another example.

[0071] The following claims are hereby incorporated into the detailed description, where each claim may stand alone as a separate example. It should also be noted that although in the claims a dependent claim refers to a specific combination with one or more other claims, other examples may also include a combination of a dependent claim with the subject matter of any other dependent or independent claim. Such combinations are expressly set forth herein, unless it is stated in an individual case that a specific combination is not intended.

Claims

1. A magnetoresistive (MR) angle sensor system (200, 300, 400) for measuring the rotation angle of a rotating component (202, 302, 402) in an out-of-axis (OOS) configuration, the MR angle sensor system (200, 300, 400) comprising: a magnet (201, 301, 401) attached to the rotating member (202, 302, 402), the magnet comprising a center and magnetic poles, and The magnetoresistive MR sensor (203, 303, 403) is configured to measure magnetic field components of the magnetic field of the magnet in a first direction and a second direction, the first direction and the second direction forming a sensitive plane, the sensitive plane being positioned with a certain offset relative to the center of the magnet (201, 301, 401) in an offset direction, the offset direction being parallel to a rotation axis corresponding to the rotating component.

2. The MR angle sensor system (200, 300, 400) according to claim 1, wherein the second direction (y) is perpendicular to the first direction (x).

3. The MR angle sensor system (200, 300, 400) according to claim 2, wherein the first direction (x) and the second direction (y) are perpendicular to the direction between the poles of the magnet (201, 301, 401).

4. The MR angle sensor system (200, 300, 400) according to claim 2, wherein the first direction (x) or the second direction (y) is parallel to a direction between magnetic poles of the magnet (201, 301, 401).

5. The MR angle sensor system (200, 300, 400) of any one of claims 2 to 4, wherein the offset is selected so that the ratio of the amplitude of the magnetic field component (Bx) in the first direction (x) to the amplitude of the magnetic field component (By) in the second direction (y) at the position of the MR sensor (203, 303, 403) is within one of the following ranges: 0.85 to 1.15; 0.9 to 1.1; or 0.95 to 1.

05.

6. The MR angle sensor system (200, 300, 400) of claim 1, wherein the offset is selected such that the amplitude of the magnetic field component (Bx) in the first direction (x) corresponds to the amplitude of the magnetic field component (By) in the second direction (y).

7. The MR angle sensor system (200, 300, 400) of claim 1, wherein the magnetic poles of the magnet (201, 301, 401) are configured to be pivotable.

8. The MR angle sensor system (200, 300, 400) of claim 1, wherein the direction between the poles of the magnet (201, 301, 401) is perpendicular to the rotation axis.

9. The MR angle sensor system (200, 300, 400) of claim 1, wherein the MR sensor (203, 303, 403) is one of an anisotropic magnetoresistive sensor; a giant magnetoresistive sensor; or a tunnel magnetoresistive sensor.

10. The MR angle sensor system (200, 300, 400) of claim 1, further comprising a circuit arrangement configured to receive information about a magnetic field component (Bx, By) measured by the MR sensor (203, 303, 403) and to determine the orientation of the magnet (201, 301, 401) based on the information about the measured magnetic field component (Bx, By).

11. The MR angle sensor system (200, 300, 400) of claim 1, further comprising: The rotating shaft forms the rotating component (202, 302, 402).

12. The MR angle sensor system (200, 300, 400) of claim 11, wherein the rotating shaft is one of a camshaft, a crankshaft, or a steering shaft.

13. A vehicle comprising the MR angle sensor system (200, 300, 400) according to any of the preceding claims.

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