Correction apparatus for angle sensor, and angle sensor

Patent metadata

Field	Value
Publication number	US-10006789-B2
Application number	US-201715455548-A
Country	US
Kind code	B2
Filing date	Mar 10, 2017
Priority date	Apr 27, 2016
Publication date	Jun 26, 2018
Grant date	Jun 26, 2018

Abstract

A correction apparatus for an angle sensor includes a correction unit for performing first correction processing on a first detection signal and performing second correction processing on a second detection signal. The first correction processing is processing for combining the first detection signal and a first correction value to generate a first corrected detection signal. The second correction processing is processing for combining the second detection signal and a second correction value to generate a second corrected detection signal. The first correction value has a first amplitude and varies with a first period. The second correction value has a second amplitude and varies with a second period. The first and second amplitudes are of the same value. The first and second periods are of the same value equal to ⅓ or ⅕ of the period of an ideal component of each of the first and second detection signals.

First claim

What is claimed is:

1. A correction apparatus for use in an angle sensor, the angle sensor including: a detection signal generation unit for generating a first detection signal and a second detection signal each having a correspondence with an angle to be detected; and an angle detection unit for generating, on the basis of the first detection signal and the second detection signal, a detected angle value having a correspondence with the angle to be detected, wherein
when the angle to be detected varies with a predetermined period, the first detection signal contains a first ideal component, a first third harmonic error component and a first fifth harmonic error component, while the second detection signal contains a second ideal component, a second third harmonic error component and a second fifth harmonic error component,
the first ideal component and the second ideal component are different in phase from each other and vary periodically in such a manner as to trace an ideal sinusoidal curve,
the first third harmonic error component is an error component equivalent to a third harmonic of the first ideal component,
the first fifth harmonic error component is an error component equivalent to a fifth harmonic of the first ideal component,
the second third harmonic error component is an error component equivalent to a third harmonic of the second ideal component, and
the second fifth harmonic error component is an error component equivalent to a fifth harmonic of the second ideal component,
the correction apparatus comprising a correction unit for performing first correction processing on the first detection signal and performing second correction processing on the second detection signal, wherein
the first correction processing is processing for combining the first detection signal and a first correction value to generate a first corrected detection signal for use in generating the detected angle value,
the second correction processing is processing for combining the second detection signal and a second correction value to generate a second corrected detection signal for use in generating the detected angle value,
the first correction value is a value having a first amplitude and varying with a first period,
the second correction value is a value having a second amplitude and varying with a second period,
the first amplitude and the second amplitude are of the same value, and
the first period and the second period are of the same value equal to ⅓ or ⅕ of the predetermined period.

2. The correction apparatus according to claim 1 , wherein the angle to be detected is an angle that the direction of a rotating magnetic field in a reference position forms with respect to a reference direction.

3. The correction apparatus according to claim 1 , wherein the first third harmonic error component and the first fifth harmonic error component are different in amplitude from each other, while the second third harmonic error component and the second fifth harmonic error component are different in amplitude from each other.

4. The correction apparatus according to claim 1 , wherein the first amplitude and the second amplitude are an absolute value of a value F for defining the first and second correction values.

5. The correction apparatus according to claim 4 , wherein the correction unit generates the first and second correction values on the basis of the value F, the first detection signal and the second detection signal.

6. The correction apparatus according to claim 4 , further comprising a correction information storage unit for storing the value F.

7. The correction apparatus according to claim 1 , wherein the first ideal component and the second ideal component are different in phase from each other by 90°.

8. The correction apparatus according to claim 4 , further comprising a correction reference information storage unit and a correction information determination unit, wherein
the correction reference information storage unit stores information about a correspondence between a parameter value and the value F, the parameter value being determined by an operation using the first detection signal and the second detection signal, and
the correction information determination unit determines the parameter value by performing the operation using the first detection signal and the second detection signal, and refers to the information stored in the correction reference information storage unit to determine the value F corresponding to the determined parameter value.

9. The correction apparatus according to claim 8 , wherein the first ideal component and the second ideal component are different in phase from each other by 90°.

10. The correction apparatus according to claim 9 , wherein the parameter value is determined from a variation component of a sum of a square of the first detection signal and a square of the second detection signal.

11. An angle sensor comprising:
a detection signal generation unit for generating a first detection signal and a second detection signal each having a correspondence with an angle to be detected;
an angle detection unit for generating, on the basis of the first detection signal and the second detection signal, a detected angle value having a correspondence with the angle to be detected; and
the correction apparatus according to claim 1 .

12. A correction apparatus for use in an angle sensor, the angle sensor including: a detection signal generation unit for generating a first detection signal and a second detection signal each having a correspondence with an angle to be detected; and an angle detection unit for generating, on the basis of the first detection signal and the second detection signal, a detected angle value having a correspondence with the angle to be detected, wherein
when the angle to be detected varies with a predetermined period, the first detection signal contains a first ideal component, a first error component, a second error component and a third error component, while the second detection signal contains a second ideal component, a fourth error component, a fifth error component and a sixth error component,
the first ideal component and the second ideal component are different in phase from each other and vary periodically in such a manner as to trace an ideal sinusoidal curve,
the first error component and the second error component are error components both equivalent to a third harmonic of the first ideal component,
the third error component is an error component equivalent to a fifth harmonic of the first ideal component,
the fourth error component and the fifth error component are error components both equivalent to a third harmonic of the second ideal component,
the sixth error component is an error component equivalent to a fifth harmonic of the second ideal component,
the second error component and the third error component are of the same amplitude, and
the fifth error component and the sixth error component are of the same amplitude,
the correction apparatus comprising:
an initial correction unit for performing first initial correction processing and second initial correction processing; and
a subsequent correction unit for performing first subsequent correction processing and second subsequent correction processing, wherein
the first initial correction processing is processing for correcting the first detection signal to generate a first initially-corrected detection signal in which the first error component is reduced relative to that in the first detection signal,
the second initial correction processing is processing for correcting the second detection signal to generate a second initially-

Assignees

• Tdk Corp

Inventors

• Mochizuki Shinichirou
• Hirabayashi Hiraku
• Umehara Tsuyoshi
• Naganuma Hiroshi
• Watanabe Kazuya

Classifications

• G01D5/16 Primary

  by varying resistance · CPC title

• G01D5/24476

  Signal processing (G01D5/2448 - G01D5/24495 take precedence) · CPC title

• G01D18/002 Primary

  Automatic recalibration (G01D18/008 takes precedence) · CPC title

• G01D5/145 Primary

  influenced by the relative movement between the Hall device and magnetic fields (see G01R33/06) · CPC title