阅读说明：本技术 电机转子位置检测方法、装置以及电机控制器 (Motor rotor position detection method and device and motor controller ) 是由 双波 诸自强 于 2020-05-18 设计创作，主要内容包括：本发明提出一种电机转子位置检测方法、装置以及电机控制器,其中,方法包括：在电机驱动回路注入频率为f的第一干扰信号后,获取驱动电流中频率为f的电流正序分量及频率为f的电流负序分量,其中,f1小于f；获取当前的驱动电流反馈值；根据当前的驱动电流反馈值,确定当前的参考系数值；根据当前的参考系数值、频率为f的电流正序分量幅值及频率为f1的电流负序分量幅值,确定当前的偏差角度；以及,根据当前的偏差角度,确定电机转子当前所在的位置。该方法根据注入的干扰信号和电机的驱动电流反馈值,确定电机的转子的偏差角度,进而通过偏差角度确定电机转子的位置,能够提高转子位置检测的准确性。(The invention provides a motor rotor position detection method, a motor rotor position detection device and a motor controller, wherein the method comprises the following steps: after a first interference signal with the frequency f is injected into a motor driving loop, acquiring a current positive sequence component with the frequency f and a current negative sequence component with the frequency f in driving current, wherein f1 is smaller than f; obtaining a current drive current feedback value; determining a current reference coefficient value according to the current driving current feedback value; determining a current deviation angle according to a current reference coefficient value, a current positive sequence component amplitude with the frequency f and a current negative sequence component amplitude with the frequency f 1; and determining the current position of the motor rotor according to the current deviation angle. According to the method, the deviation angle of the rotor of the motor is determined according to the injected interference signal and the driving current feedback value of the motor, and then the position of the rotor of the motor is determined according to the deviation angle, so that the accuracy of rotor position detection can be improved.)

1. A motor rotor position detection method is characterized by comprising the following steps:

after a first interference signal with the frequency f is injected into a motor driving loop, acquiring a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in driving current, wherein f1 is smaller than f;

obtaining a current drive current feedback value;

determining a current reference coefficient value according to the current driving current feedback value;

determining a current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f and the current negative sequence component amplitude with the frequency f 1; and the number of the first and second groups,

and determining the current position of the motor rotor according to the current deviation angle.

2. The method of claim 1, wherein before obtaining the positive sequence component of the current with frequency f and the negative sequence component of the current with frequency f1 in the driving current, further comprising:

acquiring the current rotation frequency f2 of the motor rotor;

and determining the frequency f1 of the current negative sequence component according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal.

3. The method of claim 1, wherein prior to said determining a present reference coefficient value based on said present drive current feedback value, further comprising:

when the direct-axis current and the quadrature-axis current of the motor reach set values, injecting a second interference signal into a direct-axis current regulator of the motor to obtain a first current amplitude corresponding to the second interference signal;

injecting a third interference signal into a quadrature-axis current regulator of the motor to obtain a second current amplitude corresponding to the third interference signal; and the number of the first and second groups,

and determining reference coefficient values corresponding to the set direct-axis current and quadrature-axis current according to the first current amplitude and the second current amplitude.

4. The method of claim 3, wherein determining reference coefficient values corresponding to the set direct-axis current and quadrature-axis current according to the first current magnitude and the second current magnitude comprises:

according toDetermining the corresponding relation between the set direct-axis current and quadrature-axis current and a reference coefficient value, wherein lambda is the reference coefficient value, I₁Is the first current amplitude, I₂Is the second current magnitude.

5. The method of claim 4, wherein determining a current reference coefficient value based on the current drive current feedback value comprises:

determining a current direct-axis current set value and a current quadrature-axis current set value according to the current driving current feedback value; and the number of the first and second groups,

and determining the current reference coefficient value corresponding to the current direct-axis current set value and the current quadrature-axis current set value according to the corresponding relation between the set direct-axis current and quadrature-axis current and the reference coefficient value.

6. The method of claim 3, further comprising, before the motor has reached a set value for both the direct current and the quadrature current:

and fixing the motor rotor.

7. The method of any one of claims 1-6, wherein determining the current deviation angle based on the current reference coefficient value, the magnitude of the positive sequence component of current at frequency f, and the magnitude of the negative sequence component of current at frequency f1 comprises:

according toThe current angle of deviation is determined,

wherein, theta_mFor the current deviation angle, λ is the current reference coefficient value, I_pIs the amplitude of the current positive sequence component of frequency f, I_nIs the magnitude of the negative sequence component of the current at frequency f 1.

8. The method of claim 7,

when the current quadrature axis current is a positive number, the current deviation angle is a positive number;

when the current quadrature axis current is negative, the current deviation angle is negative.

9. The method of any of claims 1-6, wherein determining the current position of the rotor of the electric machine based on the current deviation angle comprises:

acquiring a third current with the frequency f in the first coordinate axis direction and a fourth current with the frequency f in the second coordinate axis direction in the driving current;

correcting the third current and the fourth current according to the current deviation angle; and the number of the first and second groups,

and determining the current position of the motor rotor according to the corrected third current and the corrected fourth current.

10. The method of claim 9, wherein said modifying the third current and the fourth current based on the current deviation angle comprises:

according to i_αhm+ji_βhm＝(i_αh+ji_βh)e-jθ_mCorrecting the third current and the fourth current,

wherein i_αhmFor the corrected third current, i_βhmFor the corrected fourth current, i_αhIs a third current, i_βhIs a fourth current, θ_mIs the current deviation angle.

11. The method of any of claims 1-6, wherein determining the current position of the rotor of the electric machine based on the current deviation angle comprises:

acquiring a third current with the frequency f in the first coordinate axis direction and a fourth current with the frequency f in the second coordinate axis direction in the driving current;

determining the current estimated angle of the motor rotor according to the third current and the fourth current; and the number of the first and second groups,

and correcting the current estimated angle of the motor rotor by using the deviation angle, and determining the current position of the motor rotor.

12. The method of claim 11, wherein said using the deviation angle to correct the current estimated angle of the rotor of the electric machine to determine the current position of the rotor of the electric machine comprises:

according toDetermining the current position of the motor rotor,

wherein the content of the first and second substances,in order to obtain the corrected angle, the angle is,for the current estimated angle, θ_mIs a deviation angle.

13. An electric motor rotor position detecting apparatus, comprising:

the first obtaining module is used for obtaining a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in the driving current after injecting a first interference signal with the frequency f into the motor driving loop, wherein f1 is smaller than f;

the second acquisition module is used for acquiring a current drive current feedback value;

the first determining module is used for determining a current reference coefficient value according to the current driving current feedback value;

a second determining module, configured to determine a current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f, and the current negative sequence component amplitude with the frequency f 1;

and the third determining module is used for determining the current position of the motor rotor according to the current deviation angle.

14. The apparatus of claim 13, wherein before the first obtaining module obtains the positive sequence component of current with frequency f and the negative sequence component of current with frequency f1 in the driving current, the first obtaining module is further configured to:

acquiring the current rotation frequency f2 of the motor rotor;

and determining the frequency f1 of the current negative sequence component according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal.

15. A motor controller comprising a motor rotor position detecting device according to any one of claims 13 or 14.

16. A readable storage medium, having stored thereon a motor rotor position detection program which, when executed by a processor, implements a motor rotor position detection method according to any one of claims 1-12.

Technical Field

The invention relates to the technical field of motors, in particular to a motor rotor position detection method and device and a motor controller.

Background

The permanent magnet synchronous motor or the synchronous reluctance motor has the advantages of high power density and high efficiency, and is widely applied to household appliances and electric vehicles. In order to realize the stable operation of the motor under the condition without a position sensor, the rotor position detection method based on the salient polarity of the motor is widely applied. At present, when the rotor position is detected, the detected rotor position and an actual value are deviated due to the interaction coupling effect of a direct shaft and a quadrature shaft in a motor, and the detection accuracy is low.

Disclosure of Invention

The present invention is directed to solving, at least to some extent, one of the technical problems in the related art.

Therefore, a first object of the present invention is to provide a method for detecting a rotor position of a motor, which can determine an offset angle of a rotor of the motor according to an injected interference signal and a driving current feedback value of the motor, and further determine a position of the rotor of the motor according to the offset angle, thereby improving the accuracy of the rotor position detection.

The second purpose of the invention is to provide a motor rotor position detection device.

A third object of the present invention is to provide a motor controller.

A fourth object of the invention is to propose a readable storage medium.

In order to achieve the above object, an embodiment of a first aspect of the present invention provides a method for detecting a rotor position of an electric machine, including: after a first interference signal with the frequency f is injected into a motor driving loop, acquiring a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in driving current, wherein f1 is smaller than f; obtaining a current drive current feedback value; determining a current reference coefficient value according to the current driving current feedback value; determining a current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f and the current negative sequence component amplitude with the frequency f 1; and determining the current position of the motor rotor according to the current deviation angle.

According to the motor inductance detection method provided by the embodiment of the invention, firstly, after a first interference signal with the frequency f is injected into a motor driving loop, a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in driving current are obtained, and then, the current driving current feedback value is obtained; determining a current reference coefficient value according to the current driving current feedback value; determining a current deviation angle according to a current reference coefficient value, a current positive sequence component with the frequency f and a current negative sequence component with the frequency f 1; and finally, determining the current position of the motor rotor according to the current deviation angle. Therefore, the method determines the deviation angle of the rotor of the motor according to the injected interference signal and the driving current feedback value of the motor, and further determines the position of the rotor of the motor according to the deviation angle, so that the accuracy of the rotor position detection can be improved.

In addition, the motor rotor position detection method according to the above embodiment of the present invention may further have the following additional technical features:

according to an embodiment of the present invention, before the obtaining of the current positive sequence component with the frequency f and the current negative sequence component with the frequency f1 in the driving current, the method further includes:

acquiring the current rotation frequency f2 of the motor rotor;

and determining the frequency f1 of the current negative sequence component according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal.

According to an embodiment of the present invention, before said determining a current reference coefficient value according to said current driving current feedback value, further comprises: when the direct-axis current and the quadrature-axis current of the motor reach set values, injecting a second interference signal into a direct-axis current regulator of the motor to obtain a first current amplitude corresponding to the second interference signal; injecting a third interference signal into a quadrature-axis current regulator of the motor to obtain a second current amplitude corresponding to the third interference signal; and determining reference coefficient values corresponding to the set direct-axis current and quadrature-axis current according to the first current amplitude and the second current amplitude.

According to an embodiment of the present invention, the determining the reference coefficient value corresponding to the set direct-axis current and quadrature-axis current according to the first current amplitude and the second current amplitude includes: according toDetermining the corresponding relation between the set direct-axis current and quadrature-axis current and a reference coefficient value, wherein lambda is the reference coefficient value, I₁Is the first current amplitude, I₂Is the second current magnitude.

According to an embodiment of the present invention, the determining a current reference coefficient value according to the current driving current feedback value comprises: determining a current direct-axis current set value and a current quadrature-axis current set value according to the current driving current feedback value; and determining the current reference coefficient value corresponding to the current direct-axis current set value and the current quadrature-axis current set value according to the corresponding relation between the set direct-axis current and quadrature-axis current and the reference coefficient value.

According to an embodiment of the present invention, before the direct-axis current and the quadrature-axis current of the motor reach the set values, the method further includes: and fixing the motor rotor.

According to an embodiment of the present invention, the determining a current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with frequency f and the current negative sequence component amplitude with frequency f1 includes: according toDetermining a current deviation angle, wherein theta_mFor the current deviation angle, λ is the current reference coefficient value, I_pIs the amplitude of the current positive sequence component of frequency f, I_nIs the magnitude of the negative sequence component of the current at frequency f 1.

According to one embodiment of the invention, when the present quadrature axis current is a positive number, the present deviation angle is a positive number; when the current quadrature axis current is negative, the current deviation angle is negative.

According to an embodiment of the present invention, determining the current position of the rotor of the motor according to the current deviation angle includes: acquiring a third current with the frequency f in the first coordinate axis direction and a fourth current with the frequency f in the second coordinate axis direction in the driving current; correcting the third current and the fourth current according to the current deviation angle; and determining the current position of the motor rotor according to the corrected third current and the corrected fourth current.

According to an embodiment of the present invention, the correcting the third current and the fourth current according to the current deviation angle includes: according toCorrecting the third current and the fourth current, wherein i_αhmFor the corrected third current, i_βhmFor the corrected fourth current, i_αhIs a third current, i_βhIs a fourth current, θ_mIs the current deviation angle.

According to an embodiment of the present invention, determining the current position of the rotor of the motor according to the current deviation angle includes: acquiring a third current with the frequency f in the first coordinate axis direction and a fourth current with the frequency f in the second coordinate axis direction in the driving current; determining the current estimated angle of the motor rotor according to the third current and the fourth current; and correcting the current estimated angle of the motor rotor by using the deviation angle to determine the current position of the motor rotor.

According to an embodiment of the present invention, the correcting the current estimated angle of the motor rotor by using the deviation angle to determine the current position of the motor rotor includes: according toDetermining a current position of the rotor of the motor, wherein,in order to obtain the corrected angle, the angle is,for the current estimated angle, θ_mIs a deviation angle.

In order to achieve the above object, a second embodiment of the present invention provides a motor rotor position detecting device, including: the first obtaining module is used for obtaining a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in the driving current after injecting a first interference signal with the frequency f into the motor driving loop, wherein f1 is smaller than f; the second acquisition module is used for acquiring a current drive current feedback value; the first determining module is used for determining a current reference coefficient value according to the current driving current feedback value; a second determining module, configured to determine a current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f, and the current negative sequence component amplitude with the frequency f 1; and the third determining module is used for determining the current position of the motor rotor according to the current deviation angle.

According to the motor rotor position detection device provided by the embodiment of the invention, after a first interference signal with the frequency f is injected into a motor driving loop through a first acquisition module, a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in driving current are acquired; acquiring a current drive current feedback value through a second acquisition module; determining a current reference coefficient value according to a current driving current feedback value through a first determination module; determining a current deviation angle through a second determination module according to a current reference coefficient value, a current positive sequence component amplitude with the frequency f and a current negative sequence component amplitude with the frequency f 1; and determining the current position of the motor rotor according to the current deviation angle through a third determination module. Therefore, the device determines the deviation angle of the rotor of the motor according to the injected interference signal and the driving current feedback value of the motor, and then determines the position of the rotor of the motor according to the deviation angle, so that the accuracy of the rotor position detection can be improved.

In addition, the motor rotor position detection device according to the embodiment of the invention may further have the following additional technical features:

according to an embodiment of the present invention, before the first obtaining module obtains the current positive sequence component with the frequency f and the current negative sequence component with the frequency f1 in the driving current, the first obtaining module is further configured to: acquiring the current rotation frequency f2 of the motor rotor; and determining the frequency f1 of the current negative sequence component according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal.

In order to achieve the above object, a motor controller according to a third embodiment of the present invention includes a motor rotor position detecting device according to the second embodiment of the present invention.

According to the motor controller provided by the embodiment of the invention, the motor rotor position detection device provided by the embodiment of the invention can determine the deviation angle of the rotor of the motor according to the injected interference signal and the drive current feedback value of the motor, and further determine the position of the rotor of the motor through the deviation angle, so that the accuracy of rotor position detection can be improved.

To achieve the above object, a fourth aspect of the present invention provides a readable storage medium, on which a motor rotor position detection program is stored, which when executed by a processor, implements the motor rotor position detection method provided by the first aspect of the present invention.

According to the readable storage medium of the embodiment of the invention, when the motor rotor position detection program stored on the readable storage medium is executed by the processor, the deviation angle of the rotor of the motor can be determined according to the injected interference signal and the drive current feedback value of the motor, and then the position of the rotor of the motor can be determined through the deviation angle, so that the accuracy of rotor position detection can be improved.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The foregoing and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a flow chart of a method of detecting a position of a rotor of an electric machine according to an embodiment of the invention;

FIG. 2 is a schematic diagram of injecting a first interference signal according to one embodiment of the present invention;

FIG. 3 is a flow chart of calculating a plurality of reference coefficient values for a motor according to one embodiment of the present invention;

FIG. 4 is a schematic diagram of injecting a second interference signal and a third interference signal in accordance with one embodiment of the present invention;

FIG. 5 is a schematic diagram of modifying high frequency current according to one example of the invention;

fig. 6 is a block diagram of a structure of a motor rotor position detecting apparatus according to an embodiment of the present invention;

FIG. 7 is a block diagram of a first acquisition module, according to one embodiment of the invention;

FIG. 8 is a block diagram of a second acquisition module, according to one embodiment of the invention;

fig. 9 is a schematic structural view of a motor rotor position detecting apparatus according to an example of the present invention;

fig. 10 is a schematic structural view of a rotor position detecting apparatus of a motor according to another example of the present invention;

fig. 11 is a block diagram of a structure of a motor controller according to an embodiment of the present invention.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the drawings are illustrative and intended to be illustrative of the invention and are not to be construed as limiting the invention.

The following describes a motor inductance detection method, a motor inductance detection device, and a motor controller according to embodiments of the present invention with reference to the drawings.

It should be noted that, in this embodiment, a two-phase stationary coordinate system α - β may be defined, and a two-phase rotating coordinate system d-q is established on the rotor of the motor, and the coordinate system d-q rotates synchronously with the rotor, where the d-axis (straight axis) is the direction of the rotor magnetic field and the q-axis (quadrature axis) is the direction perpendicular to the rotor magnetic field. The motor rotor position detection method, device and motor controller in this embodiment are applicable to a permanent magnet synchronous motor and a synchronous reluctance motor, in which the motor has a saliency that is reflected in a structure in which the motor has a salient pole and an inductance that has a saliency due to application of a current when the motor is operating.

Fig. 1 is a flow chart of a method of detecting a position of a rotor of an electric machine according to an embodiment of the present invention.

As shown in fig. 1, the method comprises the steps of:

s101, after a first interference signal with the frequency f is injected into a motor driving loop, a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in the driving current are obtained. Wherein f1 is smaller than f, f can be high frequency (1000 Hz-2000 Hz), and the first interference signal can be orthogonal high frequency rotation voltage signal.

Specifically, as shown in fig. 2, a first interference signal with a frequency f is injected into a driving loop of the target motor, i.e., a high-frequency rotating voltage u_αh ^*And u_βh ^*Are respectively superposed to the voltage u_α ^*And u_β ^*The above. Then, the high frequency rotating voltage u_αh ^*And u_βh ^*After space voltage vector Modulation, the space voltage vector Modulation is converted into a PWM (Pulse Width Modulation) signal for driving the motor to operate, and when the driving current is stable, the sampled three-phase driving current of the motor can be analyzed to determine the current positive sequence component amplitude I with the frequency f_pAnd the amplitude I of the negative sequence component of the current with the frequency f1_n。

In general, the driving current of the motor may be stable within several periods after the interference signal is added, for example, 3 disturbing signal periods, or 5 disturbing signal periods, or 6 disturbing signal periods, which is not limited in this application.

And S102, acquiring the current drive current feedback value.

Specifically, referring to fig. 2, the three-phase driving current feedback value of the motor is converted into the driving current feedback values i of the α and β axes by the clark converter_α、i_βThe feedback value i of the driving current_α、i_βDriving current feedback value i converted into d and q axes by park converter_d、i_q。

And S103, determining a current reference coefficient value according to the current driving current feedback value.

In particular, the memory may have stored therein a recorded motor drive current i_d、i_qCorresponding relation with reference coefficient value lambda, namely (lambda, i)_d，i_q) Thus the current i has been acquired in step S102_d、i_qIn this case, the corresponding reference coefficient value λ may be obtained by referring to a three-dimensional table in the memory.

And S104, determining the current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f and the current negative sequence component amplitude with the frequency f 1.

It should be noted that, when the cross-coupling effect exists in the motor, the current rotor angle obtained by the rotor position estimatorActual angle theta to the rotor_rThere may be an error Δ θ, which varies with the actual operating point of the motor, and when the error is large, the control performance of the motor may be degraded, and even the system may be unstable. In this embodiment, the amplitude I of the current positive sequence component with frequency f is determined according to the value λ of the reference coefficient_pAnd the amplitude I of the negative sequence component of the current with the frequency f1_nCalculating the current deviation angle theta of the motor rotor_mThe deviation angle theta_mThe rotor angle error Δ θ can be eliminated.

And S105, determining the current position of the motor rotor according to the current deviation angle.

Specifically, the rotor angle output by the rotor position estimator can be compensated through the current angle deviation to eliminate the angle error; or, the high-frequency current entering the rotor position estimator is corrected through the current angle deviation, so that the rotor position estimator outputs a more accurate angle value.

It is understood that the current positive sequence component amplitude I with the frequency f is obtained in step S101 respectively_pAnd the amplitude I of the negative sequence component of the current with the frequency f1_nThereafter, a drive current feedback value i is obtained in step S102_d、i_qThen, after obtaining the current reference coefficient value λ in step S103, and acquiring the current deviation angle θ in step S104_mThe positive sequence component amplitude I may then be compared_pAnd the amplitude I of the negative sequence component of the current_nA feedback value i of the drive current_d、i_qCurrent reference coefficient value lambda and current deviation angle theta_mStored in memory to be called upon when step S105 is implemented.

Compared with the rotor position detection scheme in the related art, the motor rotor position detection method can determine the deviation angle of the rotor of the motor according to the injected interference signal and the drive current feedback value of the motor, and further eliminate the error between the rotor angle obtained by the rotor position estimator and the actual rotor angle through the deviation angle, so that the accurate position of the motor rotor obtained by the rotor position estimator is ensured, and the phenomenon of low detection accuracy of the rotor position caused by the cross coupling effect is avoided.

Therefore, the method determines the deviation angle of the rotor of the motor according to the injected interference signal and the driving current feedback value of the motor, and further determines the position of the rotor of the motor according to the deviation angle, so that the accuracy of the rotor position detection can be improved.

In an embodiment of the present invention, before obtaining the current positive sequence component with the frequency f and the current negative sequence component with the frequency f1 in the driving current in step S101, the method further includes: acquiring the current rotation frequency f2 of the motor rotor; and determining the frequency f1 of the current negative sequence component according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal.

Specifically, after a first interference signal with the frequency f is injected into the motor driving loop, the first interference signal is converted into a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in the driving current of the motor after certain conversion. The frequency f1 of the current negative sequence component is not equal to the frequency f because of the influence of the current frequency of the motor rotor, so before the current negative sequence component is obtained, the current rotation frequency f2 of the motor rotor is obtained first, and then the frequency f1 of the current negative sequence component is determined according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal. Specifically, according to the formula:

f1＝(f-2*f2) (1)

and determining the frequency f1 of the current negative sequence component, wherein f2 is the current rotation frequency of the motor rotor.

It should be noted that, in general, the current rotation frequency f2 of the motor rotor is much smaller than the frequency f of the first interference signal, so the frequency f1 of the current negative sequence component is approximately equal to the frequency f, and at this time, the acquisition of the current positive sequence component and the current negative sequence component may not depend on the current rotation frequency of the motor rotor.

In an embodiment of the present invention, before determining the current reference coefficient value according to the current driving current feedback value, i.e. before implementing the above step S103, as shown in fig. 3, the method further includes the following steps:

s301, when the direct-axis current and the quadrature-axis current of the motor both reach set values, injecting a second interference signal into the direct-axis current regulator of the motor to obtain a first current amplitude corresponding to the second interference signal. The direct-axis current regulator may be a PI (Proportional Integral) regulator. The second interference signal may be a high frequency sinusoidal voltage signal.

Specifically, the current drive current feedback value i is obtained_d、i_qThen, as shown in FIG. 4, the set direct-axis current i can be applied to the direct axis and the quadrature axis respectively_d ^*And quadrature axis current i_q ^*. The direct axis current i may then be applied_d ^*Performing PI regulation to output direct axis voltage u_d ^*Will cross-axis current i_q ^*Performing PI regulation to output quadrature axis voltage u_q ^*Applying the direct axis voltage u_d ^*And quadrature axis voltage u_q ^*Inverse park transformation is carried out to obtain voltages u corresponding to alpha and beta axes respectively_α ^*、u_β ^*According to the voltage u_α ^*And u_β ^*And controlling the target motor by adopting a space vector modulation technology.

When the direct axis current and the quadrature axis current of the motor reach a set value i_d ^*And i_q ^*Referring now to fig. 4, a second interference signal is injected into the output of the direct current regulator, i.e., a second high frequency sinusoidal voltage u_dh ^*Superimposed on the direct-axis voltage u_d ^*The above. Then, the high frequency sinusoidal voltage u_dh ^*After park inverse transformation and space voltage vector modulation, the voltage is converted into driving voltage of a target motor to drive the target motor to operate, and the amplitude of a high-frequency current signal in the driving voltage, namely the first current amplitude, can be determined by analyzing and processing the sampled driving current of the motor.

And S302, injecting a third interference signal into the quadrature-axis current regulator of the motor to obtain a second current amplitude corresponding to the third interference signal. Wherein, the quadrature axis current regulator can also be a PI regulator. The third interference signal is also a high-frequency sinusoidal voltage signal, and the amplitude and the frequency of the second interference signal and the third interference flat signal are the same.

In particular, with reference to fig. 4, a third interference signal is injected at the output of the quadrature current regulator, i.e. a third high frequency sinusoidal voltage u_qh ^*Superimposed on the direct-axis voltage u_q ^*The above. Then, the high frequency sinusoidal voltage u_qh ^*After park inverse transformation and space voltage vector modulation, the voltage is converted into the driving voltage of the target motor to drive the target motor to operate, and the height of the target motor can be determined by analyzing the sampled driving current of the motorThe frequency current signal amplitude, i.e. the first current amplitude. Wherein, before injecting the third perturbation signal, the second perturbation signal may be set to zero in order to avoid an influence of the second perturbation signal on the third perturbation signal.

S303, determining reference coefficient values corresponding to the set direct-axis current and quadrature-axis current according to the first current amplitude and the second current amplitude.

Further, determining reference coefficient values corresponding to the set direct-axis current and quadrature-axis current according to the first current amplitude and the second current amplitude, including:

according to the formula:

determining the corresponding relation between the set direct-axis current and quadrature-axis current and the reference coefficient value, wherein lambda is the reference coefficient value, I₁Is a first current amplitude, I₂Is the second current magnitude.

In particular, it is possible to use a second high-frequency sinusoidal voltage u, of the same and known amplitude and frequency_dh ^*And a third high-frequency sinusoidal voltage u_qh ^*Equation (6) is determined, and the derivation process is as follows:

second high-frequency sinusoidal voltage u injected into straight axis_dh ^*Comprises the following steps:

according to the formula:

calculating a first current amplitude I₁L in the formula (3)_dhAnd L_qhIncremental inductance, L, of direct and quadrature axes, respectively_dqnAn incremental inductance which is the cross-coupling effect of the direct axis and the quadrature axis,The phase corresponding to the PWM generation and hardware induced delay.

Third high-frequency sinusoidal voltage u injected into quadrature axis_qh ^*Comprises the following steps:

according to the formula:

calculating a second current amplitude I₂。

The incremental inductance L of the direct axis can be obtained according to the formula (3) and the formula (5)_dhAnd quadrature axis incremental inductance L_qhThe correlation between them is:

after that, the setting values i of the direct-axis current and the quadrature-axis current of the motor can be changed for a plurality of times_d ^*And i_q ^*Then, the above steps S301, S302, and S303 are repeated. According to the working characteristics of the motor, different working points of the motor correspond to different direct-axis currents and quadrature-axis currents. Therefore, each time the above steps S301, S302 and S303 are repeated, a different reference coefficient value λ, e.g., i, can be obtained according to the formula (6) from the previous round_d1 ^*And i_q1 ^*Corresponding lambda₁、i_d2 ^*And i_q2 ^*Corresponding lambda₂、i_d3 ^*And i_q3 ^*Corresponding lambda₃Repeating the steps for multiple times to obtain multiple groups of (lambda, i)_d ^*，i_q ^*) And storing the multiple groups of corresponding relations in a memory for subsequent calling.

Further, determining the current reference coefficient value according to the current driving current feedback value, i.e. the step S103, includes: determining a current direct-axis current set value and a current quadrature-axis current set value according to the current driving current feedback value; and determining the current reference coefficient value corresponding to the current direct-axis current set value and the current quadrature-axis current set value according to the corresponding relation between the set direct-axis current and quadrature-axis current and the reference coefficient value.

In particular, the feedback value i is based on the current drive current_d、i_qDetermining the current set values i of the direct-axis current and the quadrature-axis current_d ^*、i_q ^*According to the setting values i of the direct-axis current and the quadrature-axis current in the memory_d ^*、i_q ^*Corresponding relation with reference coefficient value lambda, and determining current direct-axis current and quadrature-axis current set values i_d ^*、i_q ^*The corresponding current reference coefficient value λ.

In one example, in step S301, before the direct-axis current and the quadrature-axis current of the motor both reach the set values, the method may further include: the motor rotor is fixed.

Specifically, since the injection of the disturbance signal and the subsequent processing of the motor in the embodiment of the present invention are performed in a state where the motor is stationary, the driving torque (i.e., i) needs to be generated at the target motor_d ^*≠0、i_q ^*Not equal to 0, and i_d ^*≠i_q ^*) Before the motor is used, the rotating shaft of the motor is fixed at any angle through a mechanical device, that is, before setting values are respectively applied to the direct-axis current and the quadrature-axis current, the rotor of the motor needs to be fixed, so that the motor cannot rotate due to the change of a working point, and the injection of interference signals and subsequent processing are facilitated.

In one example of the present invention, the step S104 of determining the current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f and the current negative sequence component amplitude with the frequency f1 includes:

according to the formula:

the current deviation angle is determined. Wherein, theta_mFor the current deviation angle, λ is the current reference coefficient value, I_pIs the amplitude of the current positive sequence component of frequency f, I_nIs the magnitude of the negative sequence component of the current at frequency f 1.

In particular, the voltage u can be rotated by a high-frequency sinusoidal rotation of known amplitude and frequency_αh ^*And u_βh ^*Reference coefficient value lambda, current positive sequence component amplitude I with frequency f_pAnd the amplitude I of the negative sequence component of the current with the frequency f1_nDetermining the current deviation angle theta_mThe derivation process is as follows:

high frequency sinusoidal rotation voltage u injected into the drive loop_αh ^*And u_βh ^*Respectively as follows:

corresponding high frequency current i_αAnd i_βThe formula of (1) is:

according to the formula:

calculating the amplitude I of the positive sequence current component_p. Wherein the content of the first and second substances,

according to the formula:

calculating the amplitude I of the negative sequence current component_n. Wherein the content of the first and second substances,

wherein the current deviation angle theta_mThe formula of the incremental inductance of the motor is as follows:

the current rotor angle obtained by the rotor position estimator when there is a cross-coupling effect in the motor and there is no compensation for the input or output of the rotor position estimatorActual angle theta to the rotor_rThere will be an error Δ θ, which is expressed as:

the current positive sequence component amplitude I with frequency f according to the reference coefficient value lambda is_pAnd the amplitude I of the negative sequence component of the current with the frequency f1_nCalculating the current deviation angle theta of the motor rotor_m：

Using positive sequence component amplitude I_pMinus the magnitude of the negative sequence component I_nThe square value of (d) can be given by the formula:

will be publicSubstituting equation (14) into equation (10) yields the direct axis inductance L_dhAnd quadrature axis inductance L_qhAnd defined as the inductance reference value L_baseThus, the formula can be obtained:

will be in formula (11)Replacing the inductance with the formula (14) to obtain the direct axis inductance L_dhAnd quadrature axis inductance L_qhThe formula of the product between:

incremental inductance L defining a direct axis_dhQuadrature axis incremental inductor L_qhIncremental inductance L of mutual coupling effect_dqhThe normalized inductance values of (a) are:

the left sides of equation (15) and equation (16) are expressed by the normalized inductance value in equation (17) to obtain the equation

Solving for the direct axis inductance L in equation (18)_dhQuadrature axis incremental inductor L_qhThe normalized inductance of (a) to obtain the formula:

will be given in formula (19)Substituting equation (14) results in a normalized value for the cross-coupled incremental inductance:

wherein, the mutual coupling incremental inductance L in the formula (20)_dqhSign of (d) and set quadrature axis current i_q ^*The signs of (A) and (B) are opposite. At a set quadrature axis current i_q ^*When the inductance is positive, the incremental inductance L is coupled alternately_dqhIs a positive number; at a set quadrature axis current i_q ^*When the inductance is negative, the incremental inductance L is coupled alternately_dqhIs a negative number.

According to the above equations (19), (20), (12) and the reference coefficient value λ, the following equation is calculated:

wherein the deviation angle theta_mIs opposite to the sign of the present quadrature axis current, i.e.: when the current quadrature axis current is positive, the current deviation angle theta_mIs a positive number; when the present quadrature axis current is negative, the present deviation angle theta_mIs a negative number.

Due to the injected high-frequency sinusoidal rotation voltage u_αh ^*And u_βh ^*Is known, and therefore, the current positive sequence component magnitude I_pAnd the amplitude I of the negative sequence component of the current_nIs known and the reference coefficient value λ is determined in step S103, and therefore, the right-side parameters of the above equation (21) are known, whereby the current deviation angle θ can be calculated_m。

Therefore, the deviation angle of the rotor position estimator is calculated according to the high-frequency sinusoidal rotation voltage signal injected into the driving loop and the reference coefficient value, so that the subsequent compensation of the angular error caused by the cross-coupling effect is realized.

It should be noted that the present inventionIn an embodiment, the calculated offset angle θ associated with the incremental inductance_mCan be used to compensate the rotor position estimator to remove the angular error delta theta in the rotor angle at its output. In the embodiment of the present invention, the compensation may be implemented by two compensation manners, so as to implement the step S105, which is described below by two examples:

in one example, determining the current position of the rotor of the motor according to the current deviation angle, that is, step S105, may include: acquiring a third current with the frequency f in the first coordinate axis direction and a fourth current with the frequency f in the second coordinate axis direction in the driving current; correcting the third current and the fourth current according to the current deviation angle; and determining the current position of the motor rotor according to the corrected third current and the corrected fourth current. The first coordinate axis direction may be an α axis direction, and the second coordinate axis direction may be a β coordinate axis direction.

Further, according to the current deviation angle, correcting the third current and the fourth current, including:

according to the formula:

correcting the third current and the fourth current, wherein i_αhmFor the corrected third current, i_βhmFor the corrected fourth current, i_αhIs a third current, i_βhIs a fourth current, θ_mIs the current deviation angle. Wherein the current deviation angle theta_mThat is calculated in step S104.

Specifically, as shown in fig. 9, the three-phase drive current is converted into a drive current i of α and β axes by the clark converter_α、i_βThe drive current i_α、i_βAfter low-frequency current (current lower than frequency f) in the first band-pass filter is filtered, the low-frequency current is converted into third current i of alpha axis with frequency f_αhAnd a fourth current i of frequency f beta_βhElectric powerThe current corrector obtains a third current i_αhAnd a fourth current i_βhAnd the current corrector corrects the third current i according to the formula (22)_αhAnd a fourth current i_βhMaking a correction, and then applying the corrected third current i_αhmAnd a corrected fourth current i_βhmAnd sending the current to a first rotor position estimator, and outputting the estimated rotor angle by the first rotor position estimator according to the corrected third current and the fourth current.

The operation principle of the first rotor position estimator is shown in fig. 5. Specifically, cosine values of two-fold estimated value are calculated respectivelyAnd sine valueThen calculateAndproduct of (a), calculating i_βhmAndthe product of (a); computingAndafter low-pass filtering processing is carried out on the difference value, the difference value is input into a PI controller, and an estimation value of a rotor angle is obtained after integral adjustment is carried out on an output signal after PI adjustment is carried out on the PI controller by the PI controller

Therefore, the high-frequency current in the driving current is corrected to realize the compensation of the rotor angle error, so that the first rotor position estimator outputs a more accurate rotor angle estimation value, and the more accurate rotor position is determined according to the rotor angle estimation value.

In another example, determining the current position of the rotor of the motor according to the current deviation angle, that is, step S105, may include: acquiring a third current with the frequency f in the first coordinate axis direction and a fourth current with the frequency f in the second coordinate axis direction in the driving current; determining the current estimated angle of the motor rotor according to the third current and the fourth current; and correcting the current estimated angle of the motor rotor by using the deviation angle to determine the current position of the motor rotor. The first coordinate axis direction may be an α axis direction, and the second coordinate axis direction may be a β coordinate axis direction.

Further, the step of correcting the current estimated angle of the motor rotor by using the deviation angle to determine the current position of the motor rotor includes:

according to the formula:

determining the current position of the rotor of the motor, wherein,in order to obtain the corrected angle, the angle is,for the current estimated angle, θ_mIs a deviation angle. Wherein the current deviation angle theta_mThat is calculated in step S104.

Specifically, as shown in fig. 10, the three-phase drive current is converted into a drive current i of α and β axes by the clark converter_α、i_βThe drive current i_α、i_βAfter low-frequency current (current lower than frequency f) in the second band-pass filter is filtered, the low-frequency current is converted into third current i of alpha axis with frequency f_αhAnd a fourth current i of frequency f beta_βhThe second rotor position estimator obtains a third current i_αhAnd a fourth current i_βhAnd according to the third current i_αhAnd a fourth current i_βhDetermining a current estimated angle of a rotor of an electric machineAnd the estimated angle is calculatedSent to the estimated angle corrector, and the estimated angle corrector utilizes the current deviation angle theta_mThe current estimated angle of the rotor of the motor is calculated according to the formula (23)And correcting to output the corrected angle, and further determining the current position of the motor rotor according to the corrected angle.

Therefore, the current estimation angle output by the second rotor position estimator is corrected, the rotor angle error is compensated, a more accurate rotor angle estimation value is obtained, and a more accurate rotor position is determined according to the rotor angle estimation value.

It can be understood that, during the operation of the motor, the target motor is closed-loop controlled by the driving current, specifically, the three-phase current of the actual driving current is detected and obtained, and the three-phase current is converted into the α -axis current component i after clark conversion_αAnd a beta-axis current component i_βAlpha-axis current component i_αAnd a beta-axis current component i_βConverted into a direct-axis current component i after park conversion_dAnd quadrature axis current component i_qObtaining the direct-axis current component i_dAnd quadrature axis current component i_qAnd applying the direct-axis current component i through a low-pass filter_dAnd quadrature axis current component i_qLow-pass filtering to filter out high-frequency current (disturbance signal) to obtain direct-axis current feedback quantity and quadrature-axis current feedback quantity, feeding the direct-axis current feedback quantity back to the direct-axis current input end, and feeding the quadrature-axis current backThe quantity is fed back to the quadrature axis current input end, thereby realizing the closed-loop control of the motor. Therefore, the disturbance signal is prevented from being doped in the direct-axis current feedback quantity and the quadrature-axis current feedback quantity to influence the normal operation of the motor.

In summary, according to the motor rotor position detection method provided by the embodiment of the invention, the deviation angle of the rotor of the motor is determined according to the injected interference signal and the drive current feedback value of the motor, and then the position of the motor rotor is determined through the deviation angle, so that the accuracy of rotor position detection can be improved.

In order to realize the embodiment, the invention further provides a motor rotor position detection device. Fig. 6 is a block diagram of a structure of a motor rotor position detecting apparatus according to an embodiment of the present invention.

As shown in fig. 6, the motor rotor position detection apparatus 100 includes: a first obtaining module 10, a second obtaining module 20, a first determining module 30, a second determining module 40 and a third determining module 50.

The first obtaining module 10 is configured to obtain a current positive sequence component with a frequency f and a current negative sequence component with a frequency f1 in the driving current after injecting a first interference signal with the frequency f into the motor driving loop, where f1 is smaller than f; the second obtaining module 20 is configured to obtain a current drive current feedback value; the first determining module 30 is configured to determine a current reference coefficient value according to the current driving current feedback value; the second determining module 40 is configured to determine a current deviation angle according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f, and the current negative sequence component amplitude with the frequency f 1; the third determining module 50 is configured to determine a current position of the motor rotor according to the current deviation angle.

Specifically, first, after a first interference signal with a frequency f is injected into a motor driving loop through the first obtaining module 10, a current positive sequence component with the frequency f and a current negative sequence component with the frequency f1 in the driving current are obtained; then, the second obtaining module 20 obtains the current driving current feedback value, and sends the current driving current feedback value to the first determining module 30; so that the first determining module 30 determines the current reference coefficient value according to the current driving current feedback value; finally, determining the current deviation angle through a second determining module 40 according to the current reference coefficient value, the current positive sequence component amplitude with the frequency f and the current negative sequence component amplitude with the frequency f 1; and determining the current position of the motor rotor according to the current deviation angle through the third determination module 50.

In an embodiment of the present invention, before the first obtaining module 10 obtains the current positive sequence component with the frequency f and the current negative sequence component with the frequency f1 in the driving current, the first obtaining module 10 may further be configured to: acquiring the current rotation frequency f2 of the motor rotor; and determining the frequency f1 of the current negative sequence component according to the current rotation frequency f2 of the motor rotor and the frequency f of the first interference signal.

In this embodiment, as shown in fig. 7, the first obtaining module 10 may include: the device comprises a first current regulator 11, a second current regulator 12, a coordinate converter 13 and a space voltage vector modulation unit 14. The first current regulator and the second current regulator may be both PI (Proportional Integral) regulators, and the coordinate transformer 13 is a park inverter. As shown in fig. 8, the second obtaining module 20 may include: a clarke converter 21 and a park converter 22. As shown in fig. 9 and 10, the first determining module 30 may include a memory 31.

In one example of this embodiment, as shown in fig. 9, the second determining module 40 may include: a first low pass filter 41-1, a first band pass filter 42-1, a first amplitude extractor 43-1, and a first deviation angle calculator 44-1; the third determination module 50 may include a first rotor position estimator 51-1 and a current modifier 52.

In another example of this embodiment, as shown in fig. 10, the second determining module 40 may include: a second low pass filter 41-2, a second band pass filter 42-2, a second amplitude extractor 43-2, a second deviation angle calculator 44-2; the third determination module 50 may include a second rotor position estimator 51-2 and an estimated angle correction 53.

It should be noted that the foregoing explanation of the embodiment of the method for detecting the position of the motor rotor is also applicable to the device for detecting the position of the motor rotor in this embodiment, and is not repeated herein.

According to the motor rotor position detection device provided by the embodiment of the invention, the deviation angle of the rotor of the motor is determined according to the injected interference signal and the drive current feedback value of the motor, and then the position of the rotor of the motor is determined through the deviation angle, so that the accuracy of rotor position detection can be improved.

The invention also provides a motor controller, and fig. 11 is a structural block diagram of the motor controller according to the embodiment of the invention.

As shown in fig. 11, the motor controller 1000 includes the motor rotor position detection apparatus 100 according to the above-described embodiment of the present invention.

The motor controller can determine the deviation angle of the rotor of the motor according to the injected interference signal and the driving current feedback value of the motor through the motor rotor position detection device provided by the embodiment of the invention, and further determine the position of the motor rotor through the deviation angle, so that the accuracy of rotor position detection can be improved.

Further, the present invention also provides a readable storage medium having stored thereon a motor rotor position detection program which, when executed by a processor, implements the motor rotor position detection method of the above-described embodiment of the present invention.

The readable storage medium, when the motor rotor position detection program stored thereon is executed by the processor, can determine the deviation angle of the rotor of the motor according to the injected interference signal and the driving current feedback value of the motor, and further determine the position of the rotor of the motor through the deviation angle, thereby improving the accuracy of rotor position detection.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing steps of a custom logic function or process, and alternate implementations are included within the scope of the preferred embodiment of the present invention in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the present invention.

The logic and/or steps represented in the flowcharts or otherwise described herein, e.g., an ordered listing of executable instructions that can be considered to implement logical functions, can be embodied in any computer-readable medium for use by or in connection with an instruction execution system, apparatus, or device, such as a computer-based system, processor-containing system, or other system that can fetch the instructions from the instruction execution system, apparatus, or device and execute the instructions. For the purposes of this description, a "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of the computer-readable medium would include the following: an electrical connection (electronic device) having one or more wires, a portable computer diskette (magnetic device), a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium could even be paper or another suitable medium upon which the program is printed, as the program can be electronically captured, via for instance optical scanning of the paper or other medium, then compiled, interpreted or otherwise processed in a suitable manner if necessary, and then stored in a computer memory.

It should be understood that portions of the present invention may be implemented in hardware, software, firmware, or a combination thereof. In the above embodiments, the various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, any one or combination of the following techniques, which are known in the art, may be used: a discrete logic circuit having a logic gate circuit for implementing a logic function on a data signal, an application specific integrated circuit having an appropriate combinational logic gate circuit, a Programmable Gate Array (PGA), a Field Programmable Gate Array (FPGA), or the like.

It will be understood by those skilled in the art that all or part of the steps carried by the method for implementing the above embodiments may be implemented by hardware related to instructions of a program, which may be stored in a computer readable storage medium, and when the program is executed, the program includes one or a combination of the steps of the method embodiments.

In addition, functional units in the embodiments of the present invention may be integrated into one processing module, or each unit may exist alone physically, or two or more units are integrated into one module. The integrated module can be realized in a hardware mode, and can also be realized in a software functional module mode. The integrated module, if implemented in the form of a software functional module and sold or used as a stand-alone product, may also be stored in a computer readable storage medium.

The storage medium mentioned above may be a read-only memory, a magnetic or optical disk, etc. Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made to the above embodiments by those of ordinary skill in the art within the scope of the present invention.