A linear hall detects motor rotor position error compensation method

Abstract

The application discloses a linear Hall detection motor rotor position error compensation method. Usually, two linear Halls are installed on the motor with a phase difference of 90 degrees to detect the rotor position, but there are non-ideal factors such as installation error and inherent difference of the Hall, which result in that the two-way Hall signals are not equal in amplitude and not orthogonal in phase. Through coordinate transformation, the negative sequence component h s ‑ Then, the positive sequence component h s + Finally, the separation of the positive sequence component and the negative sequence component is realized, the rotor position is calculated by using the arctangent function of the positive sequence component, and the calculated rotor position finally eliminates the double-frequency jitter in the position signal, and greatly improves the precision of the rotor position detection. Through optimization of the algorithm, the application reduces the influence of the non-ideal factors of the hardware on the position detection precision, and has great application prospect in the high-precision servo field and the ultra-high-speed motor control field.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of motor control, in particular to the field of detecting motor rotor position based on linear Hall sensors. BACKGROUND

[0002] The linear Hall detects the error of motor rotor position, the position detection signal of linear Hall exists inherent phase, amplitude error due to non-ideal factors, so that the calculated rotor position angle exists error. The present application utilizes the positive and negative sequence components in the position signal, which are respectively alternating current and direct current in the rotating orthogonal coordinate system. The negative sequence component in the linear Hall position signal is separated by coordinate transformation and filter, and the positive sequence component is obtained by subtracting the negative sequence component from the original signal, so as to eliminate the twice frequency error of the negative sequence component and improve the accuracy of rotor position detection.

[0003] The present application compensates the inherent error of hardware in algorithm from the processing of linear Hall position signal. The algorithm is simple and effective, and has wide applicability. However, there is still a constant error that does not change with the rotor position after compensation, which can be compensated by a relatively complex disturbance observer. SUMMARY

[0004] The technical problem to be solved by the present application is to provide a compensation method for linear Hall detection of motor rotor position error in view of the defects of the background art.

[0005] The present application solves the above technical problems by using the following technology:

[0006] A compensation method for linear Hall detection of motor rotor position error, characterized in that the control method comprises the following specific steps:

[0007] Step a, linear Hall detects magnetic field to obtain two-way Hall signal 、 , which is input into inverse Park transformation 1;

[0008] Step b, the negative sequence component in the inverse rotating orthogonal coordinate system is obtained by inverse Park transformation 1, which is direct current, and the positive sequence component, which is alternating current;

[0009] Step c, the obtained direct current negative sequence component and alternating current positive sequence component are input into a low-pass filter to obtain the negative sequence component in the rotating orthogonal coordinate system ;

[0010] Step d, the negative sequence component is input into inverse Park transformation 2 to obtain the component of the negative sequence component in the stationary orthogonal coordinate system coordinate system) 、 ;

[0011] Step e, subtracting the obtained 、 from the original signal 、 , so as to obtain the positive sequence component 、 ;

[0012] Step f, dividing the sine component in the positive sequence component by the cosine component to obtain the tangent value, and obtaining the rotor position angle according to the tangent value;

[0013] The method comprises two phase differences The linear Hall, the inverse Park transformation module, the low-pass filter, and the inverse tangent angle calculation module are installed; the linear Hall comprises all sensors capable of linearly reflecting the magnetic field strength through the electrical quantity of voltage or current; in the inverse Park transformation module, inverse Park transformation 1 converts the coordinates in the stationary orthogonal coordinate system into the coordinates in the inverse rotating orthogonal coordinate system, and inverse Park transformation 2 converts the coordinates in the rotating orthogonal coordinate system into the coordinates in the stationary orthogonal coordinate system; the low-pass filter (LPF) is used to realize that the attenuation degree of the high-frequency part of the input signal is greater than that of the low-frequency part of the input signal; the angle calculation module calculates the angle value corresponding to the ratio of the sine component to the cosine component in the positive sequence component through the inverse tangent trigonometric function value. The range of the angle value.

[0014] Further, in step f, the inverse tangent is not used to calculate the rotor position angle, but the phase-locked loop is used to calculate the rotor position angle:

[0015]

[0016] wherein, is the actual position angle of the rotor, is the calculated position angle; the phase-locked loop uses the PI regulator to make

[0017] calculate the rotor position angle.

[0018] Compared with the prior art, the above technical scheme has the following technical effects:

[0019] 1. The control algorithm is simple, does not occupy more calculation resources, and has good real-time performance;

[0020] 2. The error caused by the inherent non-ideal hardware factors can be compensated, and the accuracy of the rotor position angle detection is improved; BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is the schematic diagram of the algorithm of the present application.​

[0022] Figure 2 This is a schematic diagram of the phase-locked loop algorithm of the present invention.

[0023] Figure 3 This is a schematic diagram of the assembly of a Hall effect sensor according to the present invention.

[0024] Figure 4 This is a two-channel Hall output waveform of the present invention. Detailed Implementation

[0025] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings:

[0026] like Figure 3 As shown, the two linear Hall effect phase differences When installed on a motor, one of the Hall effect sensors typically coincides with one phase winding of the motor. This schematic diagram illustrates a Hall effect sensor. Coinciding with winding A;

[0027] The motor rotor has an angular velocity (Let's assume an electric angular velocity) equal to rotor angular velocity )along Figure 3 Rotate in the direction shown, and let the rotation time be... The angle through which it rotated is the rotor N-pole distance Hall effect. Angle is ;

[0028] Generally, it is assumed that the motor's magnetic field has a cosine distribution, then the output signals of the two linear Hall effect sensors are as follows: Figure 4 As shown, ideally, two signals have equal amplitude and a phase difference of 0. (Orthogonal);

[0029] However, due to non-ideal hardware factors, the two signals are actually... ,in For amplitude error, This is the phase error;

[0030] Separating the positive-sequence and negative-sequence components in the Hall signal ;

[0031] Will Perform inverse Park transform to obtain Therefore, the negative sequence component is a DC component and the positive sequence component is an AC component, so the two can be separated by a filter.

[0032] like Figure 1 As shown, a method for compensating for rotor position error in a linear Hall effect motor is characterized by comprising two phase differences. The linear Hall includes all sensors that can linearly reflect the magnetic field strength through electrical quantities (such as voltage, current, etc.);

[0033] The linear Hall includes all sensors that can linearly reflect the magnetic field strength through electrical quantities (such as voltage, current, etc.);

[0034] The inverse Park transformation module is characterized in that inverse Park transformation 1 converts the coordinates in the stationary orthogonal coordinate system into the coordinates in the inverse rotating orthogonal coordinate system, and inverse Park transformation 2 converts the coordinates in the rotating orthogonal coordinate system into the coordinates in the stationary orthogonal coordinate system;

[0035] The low-pass filter (LPF) is characterized in that the attenuation degree of the high-frequency part of the input signal is greater than that of the low-frequency part of the input signal;

[0036] The inverse tangent angle calculation module is characterized in that the angle value corresponding to the value of the tangent trigonometric function is calculated.

[0037] The present application comprises the following steps:

[0038] Step a, linear Hall detects the magnetic field to obtain two-way Hall signals , Input;

[0039] Step b, through inverse Park transformation, the negative sequence component in the inverse rotating orthogonal coordinate system is obtained, which is a direct current, and the positive sequence component, which is an alternating current;

[0040] Step c, the obtained direct current negative sequence component and alternating current positive sequence component are input into a low-pass filter to obtain the negative sequence component in the rotating orthogonal coordinate system ;

[0041] Step d, the negative sequence component is input into inverse Park transformation 2 to obtain the component of the negative sequence component in the stationary orthogonal coordinate system coordinate system) , ;

[0042] Step e, the original signal , is subtracted by the negative sequence component , , so that the positive sequence component , is obtained;

[0043] Step f, the tangent value is obtained by dividing the sine component in the positive sequence component by the cosine component, and the rotor position angle is calculated through the inverse tangent.

[0044] Figure 2 ​The schematic diagram of the phase-locked loop algorithm for calculating the rotor position angle by two linear Hall signals is given, and the angle calculation link includes but is not limited to the arctangent and the phase-locked loop algorithm,

[0045] The above merely describes the preferred embodiments of the present application. Other advantages and modifications can be easily conceived by those skilled in the art according to the above embodiments. Therefore, the present application is not limited to the above embodiments, which are merely used as examples to specifically and exemplarily describe one form of the present application. Any common change and replacement made by those skilled in the art within the scope of the technical scheme of the present application should be included in the protection scope of the present application.

Claims

1. A method of compensating for errors in the position of a rotor of a linear Hall sensing electric machine, characterized in that, The compensation method comprises the following specific steps: Step a, linear Hall detects magnetic field to get two-way Hall signal , , input to anti-Park transform 1; Step b, obtaining the negative sequence component in the inverse rotating orthogonal coordinate system by inverse Park transformation 1, which is a direct current, and the positive sequence component, which is an alternating current; Step c, the obtained direct current negative sequence component and the alternating current positive sequence component are input into a low pass filter to obtain a negative sequence component in a rotating orthogonal coordinate system ; Step d, the negative sequence component Inputting the inverse Park transformation 2, the negative sequence component is obtained in the stationary orthogonal coordinate system (x, y) Coordinate system) , ; Step e, subtracting the obtained , , , , from the original signal , ; Step f, dividing the sine component in the positive sequence component by the cosine component to obtain a tangent value, and obtaining the rotor position angle according to the tangent value; The method comprises two phase differences The installed linear Hall, inverse Park transformation module, low pass filter, arctangent angle calculation module; the linear Hall includes all sensors that can linearly reflect the magnetic field strength through the electrical quantity of voltage or current; in the inverse Park transformation module, inverse Park transformation 1 converts the coordinates in the stationary orthogonal coordinate system into the coordinates in the inverse rotating orthogonal coordinate system, and inverse Park transformation 2 converts the coordinates in the rotating orthogonal coordinate system into the coordinates in the stationary orthogonal coordinate system; the low pass filter (LPF) is characterized in that the attenuation degree of the high frequency part of the input signal is greater than that of the low frequency part of the input signal; the angle calculation module calculates the ratio of the sine component in the positive sequence component to the cosine component through the arctangent trigonometric function value The angle value in the range of 0~180 .

2. The method of claim 1, wherein the method further comprises: In step f, the rotor position angle is not calculated by using the inverse tangent, but is calculated by using a phase-locked loop: , wherein, is the actual position angle of the rotor, is the calculated position angle; the phase-locked loop causes , The rotor position angle is calculated.

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