Angle signal offset self-correction method and device based on eddy current sensor

Abstract

The invention relates to an angle signal offset self-correction method and device based on an eddy current sensor, and the method comprises the following steps: S1, initializing an output signal of an eddy current, S2, collecting four paths of eddy current signals Sin +, Sin-, Cos + and Cos-by a sensor, and carrying out the differential processing, and obtaining an original signal SinRaw signal and an original signal CosRaw signal, S3, building an angle signal correction fitting equation, processing the SinRaw signal and the CosRaw signal, and carrying out the correction of the angle signal. And S4, outputting the compensated angle signals Sin theta and Cos theta based on the correction coefficients, and outputting correction coefficients alpha 1, beta 1, alpha 2 and beta 2, the alpha 1 and the alpha 2 being gain values, and the beta 1 and the beta 2 being offset values, and S4, outputting the compensated angle signals Sin theta and Cos theta based on the correction coefficients, and outputting the angle. The method has the advantage of signal offset self-correction.

Description

Technical Field

[0001] The present invention belongs to the technical field of intelligent sensors, and in particular relates to a method and device for self-correcting angle signal offset based on an eddy current sensor. Background Art

[0002] Eddy current sensors measure displacement based on the eddy current effect. When powered, the coil of an eddy current sensor converts physical quantities like displacement into actual signals, such as current and voltage. The principle behind using an eddy current sensor to measure displacement is to place a metal conductor within a energized hollow coil. Changes in the coil's impedance then cause changes in the electrical signal, ultimately leading to displacement measurement.

[0003] In actual use, the energized coil of the eddy current sensor is limited by the process, and a certain degree of signal offset will occur. Most traditional improvement methods can only achieve hardware offset compensation, but cannot self-correct the signal offset through software algorithms. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a method and device for self-correcting the offset of an angular signal based on an eddy current sensor.

[0005] The technical solutions of the present invention are as follows:

[0006] A method for self-correcting an angular signal offset based on an eddy current sensor comprises the following steps:

[0007] S1: Initialization of the output signal of eddy current;

[0008] S2: The sensor collects four eddy current signals Sin+, Sin-, Cos+, and Cos- and performs differential processing to obtain the original signals SinRaw and CosRaw.

[0009] S3: Establish an angle signal correction fitting equation, process the SinRaw signal and CosRaw signal, and output correction coefficients σ1, β1, α2, and β2, where α1 and α2 are gain values, and β1 and β2 are offset values.

[0010] S4: Output the compensated angle signals Sinθ and Cosθ based on the correction coefficient and output the angle.

[0011] Furthermore, the step of obtaining the offset value in step S3 includes:

[0012] S31. Given the basic integral formula:

[0013] Where α is the scale value, b is the constant term, and dx represents the infinitesimal change;

[0014] S32, modeling the SinRaw signal and CosRaw signal obtained in step S2, and deriving:

[0015]

[0016] Where dx represents an infinitesimal change, Scale sin and Scale cos Represents the amplitude of the sine and cosine components of the signal, Offset sin and Offset cos is a constant term, representing the DC offset of the signal, and dθ represents the infinitesimal angular change;

[0017] S33, get β1, β2 equal to Offset sin and Offset cos .

[0018] Furthermore, the step of obtaining the gain value in step S3 includes:

[0019] S34, Given (Scale sin *Sinθ) max =(SinRaw-Offset sin ) max ;

[0020] S35, Offset can be obtained from step S32 sin , and Sinθ, Cosθ∈[-1,1], SinRaw-Offset in real-time update cycle sin The maximum and minimum values ​​of , thus obtaining:

[0021]

[0022] S36, similarly we can get

[0023] Scale cos =(CosRaw) max +β2

[0024]

[0025] Furthermore, when the original signal of the next cycle is input, the step of obtaining the correction coefficient includes:

[0026] S37, use the Sin of the previous cycle -1 、Cos -1 , α1 -1 β1 -1, α2 -1 β2 -1 , and get:

[0027] Sin=α1 -1 ×SinRaw+β1 -1

[0028] Cos = α2 -1 ×CosRaw+β2 -1 .

[0029] S38. Based on the Sin and Cos values ​​obtained in step S37, β1 and β2 of the current cycle can be obtained;

[0030] β1=Offset Sin =(Sin+Sin -1 / 2π);

[0031] β2=Offset Cos =(Cos+Cos -1 / 2π);

[0032] S39. Based on the β1 and β2 values ​​obtained in step S36 and step S38, α1 and α2 can be obtained.

[0033] Furthermore, in step S4, the angle signals Sinθ and Cosθ are calculated as follows:

[0034] Sinθ=α1×SinRaw+β1

[0035] Cosθ=α2×CosRaw+β2.

[0036] An electronic device is also provided, comprising: a processor, a memory, and a computer program stored in the memory and capable of running on the processor, wherein the computer program implements the steps of the angle signal offset self-correction method when executed by the processor.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The present invention realizes the output of correction coefficients by establishing a signal correction fitting simulation equation, and realizes self-correction of the output signal based on the correction coefficients to avoid signal offset. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a flow chart of the angle signal offset self-correction method of the present invention;

[0040] Figure 2 This is a flow chart of the angle signal offset self-correction method of the present invention after the original signal of the next cycle is input. DETAILED DESCRIPTION

[0041] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0042] like Figures 1 to 2 As shown, a method for self-correcting the angle signal offset based on an eddy current sensor includes the following contents:

[0043] S1: Initialization of the output signal of eddy current;

[0044] S2: The sensor collects four eddy current signals Sin+, Sin-, Cos+, and Cos- and performs differential processing to obtain the original signals SinRaw and CosRaw.

[0045] S3: Establish an angle signal correction fitting equation, process the SinRaw signal and CosRaw signal, and output correction coefficients α1, β1, α2, and β2, where α1 and α2 are gain values, and β1 and β2 are offset values.

[0046] S31. Given the basic integral formula:

[0047] Where α is the scale value, b is the constant term, and dx represents the infinitesimal change;

[0048] S32, modeling the SinRaw signal and CosRaw signal obtained in step S2, and deriving:

[0049]

[0050] Where dx represents an infinitesimal change, Scale sin and Scale cos Represents the amplitude of the sine and cosine components of the signal, Offset sin and Offset cos is a constant term, representing the DC offset of the signal, and dθ represents the infinitesimal angular change;

[0051] S33, get β1, β2 equal to Offset sin and Offset cos ;

[0052] S34, Given (Scale sin *Sinθ) max=(SinRaw-Offset sin ) max ;

[0053] S35, Offset can be obtained from step S32 sin , and Sinθ, Cosθ∈[-1,1], SinRaw-Offset in real-time update cycle sin The maximum and minimum values ​​of , thus obtaining:

[0054]

[0055] S36, similarly we can get

[0056] Scale cos =(CosRaw) max +β2

[0057]

[0058] When the original signal of the next cycle is input, the step of obtaining the correction coefficient includes:

[0059] S37, use the Sin of the previous cycle -1 、Cos -1 , α1 -1 β1 -1 , α2 -1 β2 -1 , and get:

[0060] Sin=α1 -1 ×SinRaw+β1 -1

[0061] Cos = α2 -1 ×CosRaw+β2 -1 .

[0062] S38. Based on the Sin and Cos values ​​obtained in step S37, β1 and β2 of the current cycle can be obtained;

[0063] β1=Offset Sin =(Sin+Sin -1 / 2π);

[0064] β2=Offset Cos =(Cos+Cos -1 / 2π);

[0065] S39, based on the β1 and β2 values ​​obtained in step S36 and step S38, α1 and α2 can be obtained.

[0066] S4: Outputting compensated angle signals Sinθ and Cosθ based on the correction coefficients and outputting the angle and speed, the output speed ω=Δθ / Δt, where Δθ is the change in angle and Δt is the change in time.

[0067] The calculation formulas for the angle signals Sinθ and Cosθ are:

[0068] Sinθ=α1×SinRaw+β1

[0069] Cosθ=α2×CosRaw+β2

[0070] Example 2

[0071] An electronic device comprises: a processor, a memory, and a computer program stored in the memory and capable of running on the processor, wherein when the computer program is executed by the processor, the steps of the angle signal offset self-correction method as described in Example 1 are implemented.

[0072] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for self-correcting angle signal offset based on an eddy current sensor, characterized by: The steps include: S1: Initialization of the output signal of eddy current; S2: The sensor collects four eddy current signals Sin+, Sin-, Cos+, and Cos- and performs differential processing to obtain the original signals SinRaw and CosRaw. S3: Establish an angle signal correction fitting equation, process the SinRaw signal and CosRaw signal, and output correction coefficients α1, β1, α2, and β2, where α1 and α2 are gain values, and β1 and β2 are offset values. S4: Output the compensated angle signals Sinθ and Cosθ based on the correction coefficient and output the angle.

2. The method for self-correcting angle signal offset based on an eddy current sensor according to claim 1, characterized in that: The step of obtaining the offset value in step S3 includes: S31. Given the basic integral formula: Where α is the scale value, b is the constant term, and dx represents the infinitesimal change; S32, modeling the SinRaw signal and CosRaw signal obtained in step S2, and deriving: Where dx represents an infinitesimal change, Scale sin and Scale cos Represents the amplitude of the sine and cosine components of the signal, Offset sin and Offset cos is a constant term, representing the DC offset of the signal, and dθ represents the infinitesimal angular change; S33, get β1, β2 equal to Offset sin and Offset cos .

3. The method for self-correcting angle signal offset based on an eddy current sensor according to claim 2, characterized in that: The step S3 of obtaining the gain value includes: S34, Given (Scale sin *Sinθ) max =(SinRaw-offset sin ) max ; S35, Offset can be obtained from step S32 sin , and Sinθ, Cosθ∈[-1,1], SinRaw-Offset in real-time update cycle sin The maximum and minimum values ​​of , thus obtaining: S36, similarly we can get Scale cos =(CosRaw) max +β2 4. The method for self-correcting angle signal offset based on an eddy current sensor according to claim 3, characterized in that: When the original signal of the next cycle is input, the step of obtaining the correction coefficient includes: S37, use the Sin of the previous cycle -1 、Cos -1 , α1 -1 β1 -1 , α2 -1 β2 -1 , and get: Sin=α1 -1 ×SinRaw+β1 -1 Cos=α2 -1 ×CosRaw+β2 -1 ; S38. Based on the Sin and Cos values ​​obtained in step S37, β1 and β2 of the current cycle can be obtained; β1=offset Sin =(Sin+Sin -1 / 2π); β2=offset Cos =(Cos+Cos -1 / 2π); S39. Based on the β1 and β2 values ​​obtained in step S36 and step S38, α1 and α2 can be obtained.

5. The method for self-correcting angle signal offset based on an eddy current sensor according to claim 1, characterized in that: In step S4, the angle signals Sinθ and Cosθ are calculated as follows: Sinθ=α1×SinRaw+β1 Cosθ=α2×CosRaw+β2.

6. An electronic device, characterized in that: include: A processor, a memory, and a computer program stored in the memory and capable of running on the processor, wherein when the computer program is executed by the processor, the steps of the angle signal offset self-correction method according to any one of claims 1 to 5 are implemented.

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