Method and device for adjusting a determination rule of an angle sensor

• US 20050278137A1
• Filed: 05/17/2005
• Published: 12/15/2005
• Est. Priority Date: 05/17/2004
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Hammerschmidt, Dirk, Granig, Wolfgang, Tatschl, David
• Granted Patent: US 7,203,618 B2
• Time in Patent Office: Days
• US Class Current: 702/151
• CPC Class Codes: G01B 21/22 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G01D 18/001 Calibrating encoders
• CPC Class Codes: G01D 5/2448 Correction of gain, threshold, offset or phase control
• CPC Class Codes: G01D 5/2449 using hard-stored calibration data

Abstract

A method for adjusting a determination rule for an error compensation of an angle sensor is designed to detect a first component of a direction along a first axis and a second component of a direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components. The method includes: detecting values of component pairs consisting of two predetermined components for the calculation of offset and/or amplitude and/or axis-angle errors. One variant consists of entering the component value pairs into an ellipse equation system, determining at least one ellipse coefficient from the ellipse equation system, and adjusting the determination rule depending on the one determined ellipse coefficient or the plurality of determined ellipse coefficients. A further variant is the determination of selected points, extremums or zero points for the determination of the offset and/or amplitude and/or axis-angle errors.

Claims

1. A method for adjusting a determination rule of an angle sensor designed to detect a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, the method comprising the steps of:

detecting five component value pairs for five different directions, wherein a component value pair includes a first component value for the first component and a second component value for the second component; and

adjusting the determination rule depending on the five component value pairs.

2. A method according to claim 1, wherein the determination rule serves for the compensation of an offset error or an amplitude error or an orthogonality error of the angle sensor.

3. A method according to claim 1, wherein determining the angle based on the first component and the second component corresponds to an angle measurement of the angle sensor, and wherein the five component value pairs are consecutive first components and second components used for the angle measurement, so that adjusting the determination rule serves for a continuous correction or recalibration of the angle sensor, and so that the actual measurement is not interrupted.

4. A method according to claim 1, wherein the step of detecting the five component value pairs defines a minimum angle between the directions of the five component value pairs.

5. A method according to claim 1, wherein an angle measurement area of the sensor is subdivided into a plurality of measurement areas by a plurality of angular thresholds, and wherein the step of detecting is performed depending on the angular thresholds such that the five different directions respectively comprise an angle in a different measurement area.

6. A method according to claim 1, wherein the step of adjusting comprises a step of entering the five component value pairs into an ellipse equation system and determining at least one ellipse coefficient from the ellipse equation system, and wherein the determination rule is performed depending on the one determined ellipse coefficient or the plurality of determined ellipse coefficients.

7. A method according to claim 1, wherein the step of determining the at least one ellipse coefficient includes a step of forming a calculation matrix and a step of performing a numerical solution algorithm to determine the ellipse coefficients.

8. A method according to claim 1, further comprising a step of adjusting a reference direction as the result of a reference signal, and wherein the angle sensor is designed such that the angle is defined with respect to the reference direction.

21. A method according to claim 1, wherein the direction is a direction of a physical field at the location of the angle sensor.

9. A method for adjusting a determination rule of an angle sensor designed to detect a first component of the direction along a first axis and a second component of a direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, the method comprising:

detecting a first maximum value and a first minimum value of a predetermined one of the first and second components; and

adjusting the determination rule depending on the first maximum value and the first minimum value.

10. A method according to claim 9, wherein the step of adjusting includes a step of determining an offset correction factor based on a first averaging of the first maximum value and the first minimum value, and the angle sensor is designed to determine an offset-corrected value for the predetermined one of the first and second components based on the offset correction factor, and to determine the angle based on the offset-corrected value.

11. A method according to claim 10, wherein the step of adjusting further includes a step of determining a gain correction factor based on a second averaging of the first maximum value and the first minimum value to determine a gain-corrected value for the predetermined one of the first and second components based on the gain correction factor, and to determine the angle based on the gain-corrected value.

12. A method according to claim 11, wherein the step of detecting comprises a step of detecting a second maximum value and a second minimum value of the other one of the predetermined first and second components, and wherein the step of adjusting includes a step of determining a further offset correction factor based on a further first averaging of the second maximum value and the second minimum value and further a step of determining a further gain correction factor based on a further second averaging of the second maximum value and the second minimum value to determine an offset-corrected value and a gain-corrected value for the other one of the predetermined first and second components based on the further offset correction factor and the further gain correction factor, and to determine the angle based on the offset-corrected value and the gain-corrected value.

13. A method according to claim 11, wherein the step of detecting comprises a step of detecting a second maximum value and a second minimum value of the other one of the first and second components and a step of detecting, for the direction where the first component assumes the first minimum value or the first maximum value, an associated value assumed by the second component, or of detecting, for the direction where the second component assumes the second minimum value or the second maximum value, an associated value assumed by the first component, and wherein the step of determining comprises determining a mapping rule from the associated value, the first minimum value, the second maximum value, the second minimum value and the second maximum value, and wherein the angle sensor is designed to obtain corrected values from the offset and gain-corrected value based on the mapping rule, and to determine the angle corrected by offset error, gain error and axis-angle error based on these corrected values.

14. A method according to claim 9, wherein the angle sensor is designed to detect the first component by means of a first magnetic field sensor and the second component by means of a second magnetic field sensor, and wherein the step of detecting comprises generating a magnetic field with rotating magnetic field direction and the detection of the first and second magnetic field directions by means of the first and second magnetic field sensors.

15. A method according to claim 12, wherein the step of determining is performed such that the angle sensor may be designed to add the offset correction factor and the predetermined one of the first and second components correctly signed to obtain the offset-corrected value.

16. A method according to claim 12, wherein the step of determining is performed such that the angle sensor may be designed to multiply the gain correction factor and the predetermined one of the first and second components to obtain the gain-corrected value.

17. A method for adjusting a determination rule of an angle sensor designed to detect a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, the method comprising:

detecting a pair of first zero passage values for the second component associated with a zero passage of the first component; and

determining a correction factor for the second component based on the pair of first zero passage values, wherein the correction factor is part of the determination rule.

18. A method according to claim 17, wherein the step of determining includes a step of entering the first zero passage values into a first equation system, and a step of solving the equation system to obtain the correction factor, wherein the correction factor is an offset or gain correction factor for the second component.

19. A method according to claim 17, wherein the step of determining includes a step of determining a provisional correction factor for the second component based on the pair of first zero passage values, and a step of detecting a provisionally corrected first zero passage value associated with a provisionally corrected first component with inclusion of the provisional correction factor, and determining the correction factor based on the provisional correction factor and the provisionally corrected first zero passage value.

20. A method according to claim 19, wherein the step of determining the provisional correction factor is a first averaging from the pair of first zero passage values.

22. A method according to claim 17, wherein the step of determining includes a further step of determining a second correction factor for the second component according to a method in accordance with claim 9.

23. A device for adjusting a determination rule of an angle sensor designed to detect a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, the device comprising:

a detector designed to detect five component value pairs for five different directions, wherein a component value pair includes a first component value for the first component and a second component value for the second component; and

an adjusting unit designed to adjust the determination rule depending on the five component value pairs.

24. A device for adjusting a determination rule of an angle sensor designed to receive a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, the device comprising:

a detector designed to detect a first maximum value and a first minimum value of a predetermined one of the first or second components; and

an adjusting unit designed to adjust the determination rule depending on the first maximum value and the first minimum value.

25. A device for adjusting a determination rule of an angle sensor designed to detect a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, the device comprising:

a detector designed to detect a pair of first zero passage values for the second component associated with a zero passage of the component; and

a determination unit designed to determine a correction factor for the second component based on the pair of first zero passage values.

26. A computer program with a program code for performing the method for adjusting a determination rule of an angle sensor designed to detect a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, when the computer program runs on a computer, the method comprising the steps of detecting five component value pairs for five different directions, wherein a component value pair includes a first component value for the first component and a second component value for the second component;

and adjusting the determination rule depending on the five component value pairs.

27. A computer program with a program code for performing the method for adjusting a determination rule of an angle sensor designed to detect a first component of the direction along a first axis and a second component of a direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, when the computer program runs on a computer, the method comprising the steps of detecting a first maximum value and a first minimum value of a predetermined one of the first and second components;

and adjusting the determination rule depending on the first maximum value and the first minimum value.

28. A computer program with a program code for performing the method for adjusting a determination rule of an angle sensor designed to detect a first component of a direction along a first axis and a second component of the direction along a second axis, and to determine an angle of the direction according to the determination rule based on the first and second components, when the computer program runs on a computer, the method comprising the steps of detecting a pair of first zero passage values for the second component associated with a zero passage of the first component;

and determining a correction factor for the second component based on the pair of first zero passage values, wherein the correction factor is part of the determination rule.