Magnet-based rotational angle sensor system

Abstract

The invention relates to a magnet-based rotational angle sensor system (10) for detecting a rotational movement of a shaft (1), comprising an exciter unit (12) with at least one exciter magnet (122), a Wiegand sensor unit (14) with a sensor coil (141) and at least one Wiegand wire (142) arranged in the sensor coil (141), a magnetic field sensor unit (16), and evaluation electronics (18), wherein: the exciter unit (12) is designed to be co-rotationally mounted with the shaft (1), and to generate an alternating exciter magnetic field locally to the Wiegand sensor unit (14) and locally to the magnetic field sensor unit (16) with a rotation of the shaft (1); the Wiegand sensor unit (14) is designed in such a way that Wiegand sensor voltage pulses (WP) are generated in the sensor coil (141) via the alternating exciter magnetic field; the magnetic field sensor unit (16) is designed to detect the alternating exciter magnetic field and to provide a corresponding magnetic field sensor signal (S); and the evaluation electronics (18) are designed to detect the Wiegand sensor voltage pulses (WP) and to determine a rotational speed (N) on this basis, and to receive the magnetic field sensor signal (S) and to determine a rotational angle value (A) on the basis of the magnetic field sensor signal (S), and wherein the evaluation electronics (18) are provided with a first compensation parameter (K1) and a second compensation parameter (K2), and the evaluation electronics (18) are designed to offset the received magnetic field sensor signal (S) alternately with the first compensation parameter (K1) and with the second compensation parameter (K2) in the determining of the rotational angle value (A).

Description

[0001] B E S C H R E I B U N G

[0002] Magnetbasiertes Drehwinkelsensorsystem

[0003] The present invention relates to a magnet-based rotation angle sensor system for detecting a rotational movement of a shaft, comprising: an excitation unit with at least one excitation magnet, a Wiegand sensor unit with a sensor coil and at least one Wiegand wire arranged in the sensor coil, a magnetic field sensor unit, and evaluation electronics, wherein: the excitation unit is designed to be mounted so as to rotate with the shaft and to generate an alternating excitation magnetic field at the location of the Wiegand sensor unit and at the location of the magnetic field sensor unit upon rotation of the shaft, the Wiegand sensor unit is designed such that Wiegand sensor voltage pulses are generated in the sensor coil by the alternating excitation magnetic field, the magnetic field sensor unit is designed to detect the alternating excitation magnetic field and to provide a corresponding magnetic field sensor signal, and the evaluation electronics is designed,to detect the Wiegand sensor voltage pulses and determine a number of revolutions based on them, and to receive the magnetic field sensor signal and determine a rotation angle value based on the magnetic field sensor signal.

[0004] Unless otherwise defined, the terms "axial", "radial" and "transverse" hereinafter refer to the shaft to be detected by the angle of rotation sensor system, regardless of whether the angle of rotation sensor system is mounted on the shaft or not. Unless otherwise stated, an axial direction is understood to be a direction extending parallel to the longitudinal axis of the shaft when the angle of rotation sensor system is mounted, a radial direction is understood to be a direction extending perpendicular to the longitudinal axis of the shaft when the angle of rotation sensor system is mounted, and a transverse plane is understood to be a plane extending transversely to the longitudinal axis of the shaft when the angle of rotation sensor system is mounted.

[0005] Angle sensor systems are also known as rotary encoders or angle sensors. In these types of angle sensor systems, the Wiegand sensor unit and the magnetic field sensor unit are typically arranged close together, so that a significant interference magnetic field is generated at the location of the magnetic field sensor unit due to the magnetization of the Wiegand wire of the Wiegand sensor unit, which is always present during operation of the angle sensor system. This causes a systematic error in the magnetic field sensor signal provided by the magnetic field sensor unit and thus in the angle value determined based on the magnetic field sensor signal.

[0006] Against this background, the task is to create a reliable and precise angle sensor system for detecting the rotational movement of a shaft.

[0007] This object is achieved by a rotation angle sensor system for detecting a rotational movement of a shaft, having the features of the main claim 1.

[0008] The angle of rotation sensor system according to the invention for detecting a rotational movement of a shaft comprises an excitation unit, a Wiegand sensor unit, a magnetic field sensor unit, and evaluation electronics. The excitation unit comprises at least one permanent-magnet excitation magnet and is designed to be mounted so as to rotate with the shaft whose rotational movement is to be detected. Typically, the excitation unit is designed to be attached to the shaft, preferably at one end of the shaft. The at least one excitation magnet is designed and arranged such that upon rotation of the shaft, and consequently upon rotation of the excitation unit, an alternating excitation magnetic field is generated at the location of the stationary Wiegand sensor unit and at the location of the stationary magnetic field sensor unit, i.e. an excitation magnetic field in which the polarity continuously reverses, i.e. the (effective) direction of the field lines continuously changes over time.

[0009] The Wiegand sensor unit comprises a sensor coil and at least one Wiegand wire arranged in the sensor coil. Wiegand wires within the meaning of the present application are also referred to as pulse wires and generally have a hard magnetic sheath and a soft magnetic core, or vice versa. Under the influence of an external magnetic field, the magnetization direction of the Wiegand wire suddenly inverts, generating a short Wiegand sensor voltage pulse in the sensor coil radially surrounding the Wiegand wire, which can be tapped via both ends of the sensor coil. This effect is referred to as the Wiegand effect and is well known in the art. The Wiegand sensor unit typically comprises a single Wiegand wire, but can also have multiple Wiegand wires, all arranged within the sensor coil.The Wiegand sensor unit, in particular the sensor coil and the at least one Wiegand wire are designed and arranged such that, when the shaft rotates, a sequence of Wiegand sensor voltage pulses, typically one Wiegand sensor voltage pulse for each alternation of the excitation magnetic field, is generated in the sensor coil by the alternating excitation magnetic field generated by the excitation unit at the location of the Wiegand sensor unit.

[0010] The magnetic field sensor unit is configured to detect the alternating excitation magnetic field and provide a corresponding magnetic field sensor signal. The magnetic field sensor unit may, for example, comprise a TMR sensor, a GMR sensor, an AMR sensor, or a Hall sensor. Preferably, the magnetic field sensor unit and the Wiegand sensor unit are arranged on a common circuit board, wherein the magnetic field sensor unit and the Wiegand sensor unit are advantageously arranged opposite one another on opposite sides of the circuit board. The magnetic field sensor signal may, for example, be an analog signal whose amplitude is proportional to a field strength or orientation of the detected excitation magnetic field, or may, for example, be a digital signal comprising a sequence of magnetic field sensor signal values, each of which is proportional to a field strength or orientation of the detected excitation magnetic field.Typically, the magnetic field sensor signal comprises a sine component and a cosine component, with the sine component being proportional to a field strength of the detected excitation magnetic field relative to a first spatial direction, and the cosine component being proportional to a field strength of the detected excitation magnetic field relative to a second spatial direction perpendicular to the first spatial direction. Typically, the magnetic field sensor signal is provided via one or more electrical contacts. In principle, however, the magnetic field sensor signal can be provided in any desired manner.

[0011] The evaluation electronics are electrically connected to the Wiegand sensor unit and are configured to detect the Wiegand sensor voltage pulses and, based thereon, specifically based on a number of detected Wiegand sensor voltage pulses and their polarity, to determine a number of revolutions in a known manner. The evaluation electronics are further configured to receive the magnetic field sensor signal from the magnetic field sensor unit and, based on the magnetic field sensor signal, to determine a rotation angle value in a known manner. For the transmission of the magnetic field sensor signal, the evaluation electronics are typically electrically connected to the magnetic field sensor unit. The evaluation electronics are preferably arranged together with the magnetic field sensor unit and the Wiegand sensor unit on a common circuit board.The evaluation electronics typically comprise at least one integrated circuit, in particular an application-specific integrated circuit (ASIC) and / or a field programmable gate array (FPGA), and / or a microcontroller. In principle, however, the evaluation electronics can be formed by any electrical circuit suitable for detecting the Wiegand sensor voltage pulses and determining the number of revolutions based thereon, as well as for receiving the magnetic field sensor signal and determining the angle of rotation value based thereon.

[0012] When the shaft rotates, a magnetization direction of the Wiegand wire of the Wiegand sensor unit changes continuously due to the alternating excitation magnetic field, whereby depending on the current magnetization direction, a different effect of the interference magnetic field generated by the magnetized Wiegand wire results on the magnetic field detected by the magnetic field sensor unit and thus on the magnetic field sensor signal provided by the magnetic field sensor unit.According to the invention, a first compensation parameter and a second compensation parameter are therefore provided to the evaluation electronics, and the evaluation electronics are designed to alternately calculate the received magnetic field sensor signal with the first compensation parameter and the second compensation parameter when determining the angle of rotation value in order to compensate for the effects of the two different magnetization directions of the Wiegand wire that occur during operation on the magnetic field sensor signal. This creates a reliable and precise angle of rotation sensor system. The two compensation parameters can generally be implemented as a single compensation value or as a vector with multiple compensation values.Typically, the received magnetic field sensor signal has a sine component and a cosine component, wherein the sine component is proportional to a field strength of the detected excitation magnetic field relative to a first spatial direction and the cosine component is proportional to a field strength of the detected excitation magnetic field relative to a second spatial direction perpendicular to the first spatial direction. In this case, it is conceivable, for example, that the two compensation parameters each comprise an individual compensation value for the sine component and for the cosine component. It is also conceivable that one of the two compensation parameters is zero or a zero vector. Preferably, the corresponding compensation parameter is added to or subtracted from a current magnetic field sensor signal value when computed with the magnetic field sensor signal. This enables particularly simple compensation.In principle, however, it is also conceivable that the corresponding compensation parameter is multiplied, divided, or calculated in a more complex way with a current magnetic field sensor signal value when calculated with the magnetic field sensor signal. In any case, however, the magnetic field sensor signal is calculated alternately, i.e., alternately, with either the first compensation parameter or the second compensation parameter. Preferably, the evaluation electronics are configured to determine a current quadrant parameter based on the detected Wiegand sensor voltage pulses and / or the received magnetic field sensor signal. This quadrant parameter indicates in which 90° quadrant of the 360° full rotation the excitation unit rotating with the shaft is currently located, and to decide, based on the current quadrant parameter, which of the two compensation parameters the magnetic field sensor signal is calculated with.

[0013] In principle, the two compensation parameters can be provided to the evaluation electronics in any desired manner, for example, via a data interface from an external system. However, the angle of rotation sensor system according to the invention preferably comprises a data memory, advantageously non-volatile, in which the first compensation parameter and the second compensation parameter are stored and to which the evaluation electronics has at least read access. This makes it possible, for example, to determine the two compensation parameters once on a test bench and then permanently store them in the data memory. The data memory can also be integrated, for example as a so-called flash memory, together with the evaluation unit in an integrated circuit or a microcontroller.However, it is also conceivable that the angle of rotation sensor system has a data interface via which the compensation parameters stored in the data memory can be subsequently changed.

[0014] In general, a Wiegand sensor voltage pulse is generated in the sensor coil each time the magnetization direction of the Wiegand wire changes. The occurrence of a Wiegand sensor voltage pulse thus indicates a change in the magnetization direction of the Wiegand wire. Therefore, upon detection of a Wiegand sensor voltage pulse, the evaluation electronics are preferably configured to switch from calculating the received magnetic field sensor signal with the first compensation parameter to calculating the received magnetic field sensor signal with the second compensation parameter, or from calculating the received magnetic field sensor signal with the second compensation parameter to calculating the received magnetic field sensor signal with the first compensation parameter.This enables a simple yet relatively reliable determination of the times at which the compensation parameter changes from one to the other, for which no special means for detecting or monitoring the current magnetization direction of the Wiegand wire are required.

[0015] As previously described, the received magnetic field sensor signal typically has a sine component and a cosine component, wherein the sine component is proportional to the field strength of the detected excitation magnetic field relative to the first spatial direction, and the cosine component is proportional to the field strength of the detected excitation magnetic field relative to the second spatial direction perpendicular to the first spatial direction. Since the Wiegand wire is generally arranged substantially parallel to one of these two spatial directions, the interference magnetic field generated by the Wiegand wire typically significantly influences either only the sine component of the magnetic field sensor signal or only the cosine component of the magnetic field sensor signal.In order to enable a particularly simple compensation of the influence of the disturbing magnetic field, the evaluation electronics in this case are therefore preferably designed to calculate the first compensation parameter or the second compensation parameter either only with the sine component or only with the cosine component.

[0016] The evaluation electronics preferably comprise an integrated circuit, particularly preferably an ASIC, which is designed to detect the Wiegand sensor voltage pulses and, based thereon, to determine the number of revolutions, and a microcontroller which is designed to receive the magnetic field sensor signal, determine the rotation angle value based on the received magnetic field sensor signal, and, when determining the rotation angle value, alternately calculate the received magnetic field sensor signal with the first compensation parameter and the second compensation parameter. The detection of the Wiegand sensor voltage pulses and the determination of the number of revolutions, which essentially corresponds to incrementing or decrementing a count value when a Wiegand sensor voltage pulse occurs, can be implemented particularly efficiently using an integrated circuit, i.e., an ASIC, specifically designed for this purpose.The integrated circuit is electrically connected to the Wiegand sensor unit to detect the Wiegand sensor voltage pulses. The integrated circuit is typically also connected to a data memory in which at least one count value representing the number of revolutions is stored. However, determining the angle of rotation based on the received magnetic field sensor signal using the two compensation parameters can be implemented particularly efficiently using an appropriately programmed microcontroller.

[0017] Preferably, the integrated circuit is designed to provide a detection signal each time a Wiegand sensor voltage pulse is detected, and the microcontroller is designed to receive the detection signal and, in response to the detection signal, to switch from calculating the received magnetic field sensor signal with the first compensation parameter to calculating the received magnetic field sensor signal with the second compensation parameter or from calculating the received magnetic field sensor signal with the second

[0018] Compensation parameters are used to offset the received magnetic field sensor signal against the first compensation parameter. This creates a particularly efficient angle sensor system.

[0019] An integrated circuit configured to detect the Wiegand sensor voltage pulses and, based thereon, to

[0020] The number of revolutions to determine is often already present. In order to avoid a generally relatively costly redesign / redesign of the integrated circuit, in an alternative preferred embodiment of the invention, the microcontroller is electrically connected to the Wiegand sensor unit and configured to directly detect the Wiegand sensor voltage pulses and, upon detection of a Wiegand sensor voltage pulse, to switch from calculating the received magnetic field sensor signal with the first compensation parameter to calculating the received magnetic field sensor signal with the second compensation parameter or from calculating the received magnetic field sensor signal with the second compensation parameter to calculating the received magnetic field sensor signal with the first compensation parameter.

[0021] An embodiment of the present invention is described below with reference to the accompanying figures. Figure 1 shows a schematic diagram of a rotation angle sensor system according to the invention mounted on a shaft for detecting a rotational movement of the shaft.

[0022] Figure 2 schematically shows connections between components of the rotation angle sensor system in a preferred embodiment,

[0023] Figure 3 schematically shows connections between the components of the rotation angle sensor system in an alternative preferred embodiment, and

[0024] Figure 4 schematically shows time courses of a magnetic field sensor signal provided by a magnetic field sensor unit of the rotation angle sensor system from Figure 1, a compensated magnetic field sensor signal obtained by calculating the magnetic field sensor signal with compensation parameters, of

[0025] Wiegand sensor voltage pulses generated in a Wiegand sensor unit of the rotation angle sensor system of Figure 1 and a detection signal provided by an integrated circuit of the rotation angle sensor system of Figure 1.

[0026] Fig. 1 shows a rotation angle sensor system 10 arranged at an axial end of a shaft 1 to detect a rotational movement of the shaft 1. The rotation angle sensor system 10 comprises an excitation unit 12 attached to the shaft 1. The rotation angle sensor system 10 further comprises a Wiegand sensor unit 14, a magnetic field sensor unit 16, and evaluation electronics 18, which are arranged on a circuit board 20 attached to a housing part 2.

[0027] The excitation unit 12 comprises a magnet carrier 121, which is attached to an end face of the shaft 1. The excitation unit 12 further comprises two permanent-magnet excitation magnets 122, which are magnetized and arranged on the magnet carrier 121 in such a way that an alternating excitation magnetic field is generated by the excitation magnets 122 both at the location of the Wiegand sensor unit 14 and at the location of the magnetic field sensor unit 16 upon rotation of the shaft 1.

[0028] The Wiegand sensor unit 14 is arranged on an axial side of the circuit board 20 facing away from the shaft 1 and comprises a sensor coil 141 and a Wiegand wire 142 arranged within the sensor coil 141. The sensor coil 141 and the Wiegand wire 142 are designed and arranged such that a sequence of Wiegand sensor voltage pulses WP is generated in the sensor coil 141 by the alternating excitation magnetic field generated by the excitation magnets 122 upon rotation of the shaft 1, as schematically illustrated in Fig. 4, wherein the Wiegand sensor voltage pulses WP can be tapped via the two ends of the sensor coil 141.

[0029] The magnetic field sensor unit 16 is arranged opposite the Wiegand sensor unit 14 on an axial side of the circuit board 20 facing the shaft 1. The magnetic field sensor unit 16 is designed to detect the alternating excitation magnetic field and, as schematically shown in Fig. 4, to provide a corresponding magnetic field sensor signal S with a sine component S1 and a cosine component S2 to electrical contacts provided for this purpose. In the present exemplary embodiment, the sine component S1 is proportional to a field strength of the detected excitation magnetic field relative to a spatial direction parallel to a longitudinal axis of the Wiegand wire 142, and the cosine component S2 is proportional to a field strength of the detected excitation magnetic field relative to a spatial direction perpendicular to the longitudinal axis of the Wiegand wire 142. The evaluation electronics 18 comprises an integrated circuit 181, a microcontroller 182, and a data memory 183.

[0030] The integrated circuit 181 is electrically connected to the Wiegand sensor unit 14 and is configured to detect the Wiegand sensor voltage pulses WP generated in the sensor coil 141. The integrated circuit 181 is further configured to determine a number of revolutions N based on a number and polarity of the detected Wiegand sensor voltage pulses WP and to store this number in the data memory 183.

[0031] The microcontroller 182 is electrically connected to the electrical contacts of the magnetic field sensor unit 16 provided for providing the magnetic field sensor signal S and is configured to receive the magnetic field sensor signal S. The microcontroller 182 is further configured to read from the data memory 183 a first compensation parameter K1 stored in the data memory 183 and a second compensation parameter K2 stored in the data memory 183. The microcontroller 182 is further configured to alternately calculate the magnetic field sensor signal S, as schematically illustrated in Fig. 4, with the first compensation parameter K1 and the second compensation parameter K2 in order to determine a compensated magnetic field sensor signal S-comp.Specifically, the microcontroller 182 is configured to alternately add the first compensation parameter K1 and the second compensation parameter K2 to the sine component S1 of the magnetic field sensor signal S to determine a compensated sine component S1-comp, which, together with the cosine component S2, forms the compensated magnetic field sensor signal S-comp. The microcontroller 182 is further configured to determine a rotation angle value A based on the compensated magnetic field sensor signal S-comp and to store it in the data memory 183.

[0032] In a preferred embodiment of the angle sensor system 10, schematically illustrated in Fig. 2, the integrated circuit 181 is configured, as schematically illustrated in Fig. 4, to provide a detection signal D at a designated electrical contact each time a Wiegand sensor voltage pulse WP is detected. In this embodiment, the microcontroller 182 is electrically connected to the corresponding electrical contact of the integrated circuit 181 and configured to receive the detection signal D.Furthermore, in this case, the microcontroller 182 is designed, in response to the receipt of the detection signal D, to switch each time from an addition of the first compensation parameter K1 to the sine component S1 to an addition of the second compensation parameter K2 to the sine component S1 or vice versa, i.e. to switch each time from an offset of the magnetic field sensor signal S with the first compensation parameter K1 to an offset of the magnetic field sensor signal S with the second compensation parameter K2 or vice versa.

[0033] In an alternative embodiment of the rotation angle sensor system 10, schematically illustrated in Fig. 3, the microcontroller 182 is electrically connected to the Wiegand sensor unit 14 and configured to detect the Wiegand sensor voltage pulses WP generated in the sensor coil 141. Furthermore, in this case, the microcontroller 182 is configured, upon detection of a Wiegand sensor voltage pulse WP, to switch each time from adding the first compensation parameter K1 to the sine component S1 to adding the second compensation parameter K2 to the sine component S1, or vice versa, i.e., to switch each time from calculating the magnetic field sensor signal S with the first compensation parameter K1 to calculating the magnetic field sensor signal S with the second compensation parameter K2, or vice versa.

[0034] List of reference symbols

[0035] 1 wave

[0036] 2 Housing part

[0037] 10 Angle sensor system

[0038] 12 Excitation unit

[0039] 121 magnetic carriers

[0040] 122 excitation magnets

[0041] 14 Wiegand sensor unit

[0042] 141 Sensor coil

[0043] 142 Wiegand wire

[0044] 16 Magnetic field sensor unit

[0045] 18 Evaluation electronics

[0046] 181 integrated circuit

[0047] 182 microcontrollers

[0048] 183 data storage

[0049] 20 boards

[0050] A rotation angle value

[0051] D detection signal

[0052] K1,K2 compensation parameters

[0053] N number of revolutions

[0054] S Magnetic field sensor signal

[0055] 51 sinusoidal component

[0056] 52 cosine component

[0057] S-comp compensated magnetic field sensor signal

[0058] Sl-comp compensated sine component

[0059] WP Wiegand sensor voltage pulses

Claims

PATENT CLAIMS Magnet-based rotation angle sensor system (10) for detecting a rotational movement of a shaft (1), comprising: - an excitation unit (12) with at least one excitation magnet (122), - a Wiegand sensor unit (14) with a sensor coil (141) and at least one Wiegand wire (142) arranged in the sensor coil (141), - a magnetic field sensor unit (16), and - an evaluation electronics (18), wherein: - the excitation unit (12) is designed to be mounted so as to rotate with the shaft (1) and to generate an alternating excitation magnetic field at the location of the Wiegand sensor unit (14) and at the location of the magnetic field sensor unit (16) when the shaft (1) rotates, - the Wiegand sensor unit (14) is designed such that Wiegand sensor voltage pulses (WP) are generated by the alternating excitation magnetic field in the sensor coil (141), - the magnetic field sensor unit (16) is designed to detect the alternating excitation magnetic field and to provide a corresponding magnetic field sensor signal (S), and - the evaluation electronics (18) are designed to detect the Wiegand sensor voltage pulses (WP) and to determine a number of revolutions (N) based thereon, as well as to receive the magnetic field sensor signal (S) and to determine a rotation angle value (A) based on the magnetic field sensor signal (S), characterized in that A first compensation parameter (K1) and a second compensation parameter (K2) are provided to the evaluation electronics (18), and the evaluation electronics (18) are configured to alternately calculate the received magnetic field sensor signal (S) with the first compensation parameter (K1) and with the second compensation parameter (K2) when determining the rotation angle value (A). The magnet-based rotation angle sensor system (10) according to claim 1, comprising a data memory (183) in which the first compensation parameter (K1) and the second compensation parameter (K2) are stored and to which the evaluation electronics (18) has access.Magnet-based rotation angle sensor system (10) according to one of the preceding claims, wherein the evaluation electronics (18) are designed, upon detection of a Wiegand sensor voltage pulse (WP), to change from an offsetting of the received magnetic field sensor signal (S) with the first compensation parameter (K1) to an offsetting of the received magnetic field sensor signal (S) with the second compensation parameter (K2) or from one. Computation of the received magnetic field sensor signal (S) with the second compensation parameter (K2) to calculate the received magnetic field sensor signal (S) with the first compensation parameter (K1). A magnet-based rotation angle sensor system (10) according to one of the preceding claims, wherein: - the received magnetic field sensor signal (S) has a sine component (S1) and a cosine component (S2), and - the evaluation electronics (18) are configured to calculate the first compensation parameter (K1) or the second compensation parameter (K2) only with the sine component (S1) or only with the cosine component (S2). A magnetic-based rotation angle sensor system (10) according to one of the preceding claims, wherein the evaluation electronics (18) comprises: - an integrated circuit (181) designed to detect the Wiegand sensor voltage pulses (WP) and to determine the number of revolutions (N) based thereon, and - a microcontroller (182) configured to receive the magnetic field sensor signal (S), to determine the angle of rotation value (A) based on the received magnetic field sensor signal (S), and to offset the received magnetic field sensor signal (S) alternately with the first compensation parameter (K1) and with the second compensation parameter (K2) when determining the angle of rotation value (A). The magnetic-based angle of rotation sensor system (10) according to claim 5, wherein: - the integrated circuit (181) is designed to provide a detection signal (D) each time a Wiegand sensor voltage pulse (WP) is detected, and - the microcontroller (182) is designed to receive the detection signal (D) and, in response to the detection signal (D), to change from calculating the received magnetic field sensor signal (S) with the first compensation parameter (K1) to calculating the received magnetic field sensor signal (S) with the second compensation parameter (K2) or from Computation of the received magnetic field sensor signal (S) with the second compensation parameter (K2) to compute the received magnetic field sensor signal (S) with the first compensation parameter (K1). The magnet-based rotation angle sensor system (10) according to claim 5, wherein the microcontroller (182) is configured to detect the Wiegand sensor voltage pulses (WP) and, upon detection of a Wiegand sensor voltage pulse (WP), to switch from computation of the received magnetic field sensor signal (S) with the first compensation parameter (K1) to computation of the received magnetic field sensor signal (S) with the second compensation parameter (K2) or from computation of the received magnetic field sensor signal (S) with the second compensation parameter (K2) to computation of the received magnetic field sensor signal (S) with the first compensation parameter (K1).

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