阅读说明：本技术 用于永磁同步电机参数的辨识方法 (Identification method for permanent magnet synchronous motor parameters ) 是由 杨明 龙江 徐殿国 于 2019-10-25 设计创作，主要内容包括：本发明提供了一种用于永磁同步电机的参数辨识方法,包括：在第一设定角度下依次输入频率值为ω<Sub>h1</Sub>,幅值不同的两个或两个以上的d轴电压信号,并根据所述d轴电压信号的频率值、幅值及d轴电流确定d轴电感参数L<Sub>d</Sub>；在第二设定角度下依次输入频率值为ω<Sub>h2</Sub>,幅值不同的两个或两个以上的q轴电压信号,并根据所述q轴电压信号的频率值、幅值及q轴电流确定q轴电感参数L<Sub>q</Sub>；d轴输入第一斜坡电压信号,并根据所述第一斜坡电压信号的幅值及d轴电流确定定子电阻Rs。本发明实施例公开的用于永磁同步电机的参数辨识方法简单易行,具有很好的工程意义和实用价值。(The invention provides parameter identification method for a permanent magnet synchronous motor, which comprises the step of sequentially inputting a frequency value omega under a -th set angle h1 Two or more d-axis voltage signals with different amplitudes, and determining a d-axis inductance parameter L according to the frequency value and the amplitude of the d-axis voltage signals and the d-axis current d (ii) a Sequentially inputting the frequency value omega under a second set angle h2 Two or more q-axis voltage signals with different amplitudes, and determining a q-axis inductance parameter L according to the frequency value and the amplitude of the q-axis voltage signals and the q-axis current q The parameter identification method for the permanent magnet synchronous motor is simple and easy to implement and has good engineering performance, and a ramp voltage signal is input into the d axis, and the stator resistance Rs. is determined according to the amplitude of the ramp voltage signal and the d axis currentMeaning and practical value.)

1, method for identifying permanent magnet synchronous motor parameters, comprising:

sequentially inputting the frequency value omega under the set angle of _h1Two or more different amplitudesAnd determining a d-axis inductance parameter L according to the frequency value and the amplitude of the d-axis voltage signal and the amplitude of the d-axis current_d；

Sequentially inputting the frequency value omega under a second set angle_h2Two or more q-axis voltage signals with different amplitudes, and determining a q-axis inductance parameter L according to the frequency value and the amplitude of the q-axis voltage signal and the amplitude of the q-axis current_q；

The th ramp voltage signal is input to the d-axis, and the stator resistance Rs is determined according to the amplitude of the th ramp voltage signal and the d-axis current.

2. The method of claim 1, wherein a d-axis inductance parameter, L, is determined based on a frequency value, an amplitude value, and a d-axis current amplitude value of the d-axis voltage signal_dThe method comprises the following steps:

obtaining d-axis current extreme value i corresponding to d-axis voltage signals with different amplitudes_dmax；

According to the frequency value and the amplitude of the d-axis voltage signal and the d-axis current extreme value i_dmaxDetermining d-axis inductance parameter L_d。

3. The method of claim 2, wherein the d-axis inductance parameter L is determined when there are two input d-axis voltage signals_dThe method comprises the following steps:

at the set angle of , the frequency value ω is input_h1Extreme values are U respectively_dh1And U_dh2A d-axis voltage signal of (a);

obtaining an extreme value of U_dh1 d-th axis current extreme i_dmax1And extreme value of U_dh2Second d-axis current limit value i of time_dmax2；

According to the frequency value omega_h1 d-th axis current limit value i_dmax1And said second d-axis current limit i_dmax2And U_dh1And U_dh2Determining d-axis inductance parameter L_d。

4. The method of claim 1, wherein the method is based onDetermining q-axis inductance parameter L by using frequency value and amplitude of q-axis voltage signal and q-axis current amplitude_qThe method comprises the following steps:

obtaining q-axis current extreme value i corresponding to q-axis voltage signals with different amplitudes_qmax；

According to the frequency value and the amplitude of the q-axis voltage signal and the extreme value i of the q-axis current_qmaxDetermining a q-axis inductance parameter L_q。

5. The method of claim 4, wherein the q-axis inductance parameter L is determined when there are two input q-axis voltage signals_qThe method comprises the following steps:

inputting the frequency value omega under the second set angle_h2Extreme values are U respectively_qh1And U_qh2Q-axis voltage signal of (a);

obtaining an extreme value of U_qh1Current extreme i of q-axis of time_qmax1And extreme value of U_qh2Second q-axis current extreme i of time_qmax2；

According to the frequency value omega_h2 q-axis current limit value i_qmax1And said second q-axis current limit i_qmax2And U_qh1And U_qh2Determining q-axis inductance parameter L_q。

6. The method of claim 1, wherein determining the stator resistance Rs comprises:

the d-axis inputs the th ramp voltage signal;

sampling the th ramp voltage signal and the d-axis current to obtain a sampled ramp voltage U_dkAnd sampling d-axis current i_dk；

According to the sampling ramp voltage U_dkAnd sampling d-axis current i_dkThe stator resistance Rs is determined.

7. The method of claim 6, wherein the ramp voltage U is based on the sampling_dkAnd sampling d-axis current i_dkThe stator resistance Rs is determined by linear fitting.

8. The method of any of claims 1 to 7 and , wherein the d-axis voltage signal has a frequency value ω_h1And a frequency value ω of said q-axis voltage signal_h2And the working frequency is greater than the rated working frequency of the permanent magnet synchronous motor.

9. The method of any of claims 1-7 and , wherein the d-axis current limit value i_dmaxAnd said q-axis current limit i_qmaxAnd the current value is less than or equal to the rated current value of the permanent magnet synchronous motor.

10. The method of any of claims 1 to 7 and , further comprising:

the q-axis input second slope voltage signal is used for adjusting the q-axis input voltage signal when the feedback rotating speed of the rotor reaches th set rotating speed W1, so that the feedback rotating speed of the rotor meets th set rotating speed W1 within set time;

determining the average value u of the q-axis voltage in the set time_q1_ ave, q-axis current average i_q1_ ave and rotor feedback speed average value omega_e1_ave；

Inputting a third slope voltage signal into a q shaft, and when the feedback rotating speed of the rotor reaches W2, adjusting the input voltage signal of the q shaft to enable the feedback rotating speed of the rotor to meet a second set rotating speed W2 within set time;

determining the average value u of the q-axis voltage in the set time_q2_ ave, q-axis current average i_q2_ ave and rotor feedback speed average value omega_e2_ave；

According to the voltage average value u_q1_ ave, q-axis current average i_q1_ ave, average value ω of rotor feedback rotation speed_e1_ ave, q-axis voltage average u_q2_ ave, q-axis current average i_q2_ ave, mean value of rotor feedback speed ω_e2_ ave and the stator resistance Rs, identifying the permanent magnet flux linkage

Technical Field

The invention relates to the technical field of permanent magnet synchronous motor control, in particular to an identification method for parameters of a permanent magnet synchronous motor.

Background

The alternating current servo system mostly adopts the permanent magnet synchronous motor, and the accurate acquisition of the parameters of the permanent magnet synchronous motor is very important for the design of a high-performance motor control system, and the motor parameters are very important for high-performance control strategies, such as the design of current prediction control.

In the process of implementing the embodiments of the present disclosure, it is found that at least the following problems exist in the related art: the existing off-line parameter identification methods are all provided with a current Proportional Integral (PI) controller, and the setting of the PI parameter of the current loop needs to be carried out according to the inductance and resistance parameters of a controlled motor, so that for the motor with unknown parameters, the PI parameter setting of the current loop needs to be carried out according to the test, which affects the control precision of the current loop and even affects the parameter identification effect.

Disclosure of Invention

The embodiment of the present disclosure provides methods for identifying parameters of a permanent magnet synchronous motor, so as to solve the above technical problems, simplify the conditions required for identifying the parameters, and make the proposed identification strategy independent of a current loop and a speed loop.

The following presents a simplified summary in order to provide a basic understanding of aspects of the disclosed embodiments, including , which is not an extensive overview nor is it intended to identify key/critical elements or to delineate the scope of such embodiments, the sole is to present concepts in a simplified form as a prelude to the more detailed description that is presented later.

The embodiment of the disclosure provides parameter identification methods for a permanent magnet synchronous motor.

In , a method for identifying parameters of a permanent magnet synchronous motor includes:

sequentially inputting the frequency value omega under the set angle of _h1Two or more d-axis voltage signals with different amplitudes, and determining a d-axis inductance parameter L according to the frequency value and the amplitude of the d-axis voltage signals and the d-axis current_d；

Sequentially inputting the frequency value omega under a second set angle_h2Two or more q-axis voltage signals with different amplitudes, and determining the q-axis voltage signal according to the frequency value and the amplitude of the q-axis voltage signal and the q-axis currentQ-axis fixed inductance parameter L_q；

The th ramp voltage signal is input to the d-axis, and the stator resistance Rs is determined according to the amplitude of the th ramp voltage signal and the d-axis current.

The identification method for the parameters of the permanent magnet synchronous motor provided by the embodiment of the disclosure has the following beneficial effects:

the embodiment of the invention can realize the identification of the parameters of the permanent magnet synchronous motor, does not need to construct a speed closed loop and a current closed loop in the identification process of the parameters of the permanent magnet synchronous motor, and has simple structure, simple calculation process and no need of complex data analysis.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification , illustrate embodiments consistent with the invention and together with the description , serve to explain the principles of the invention.

Fig. 1 is a schematic flow diagram illustrating methods for identifying parameters of a permanent magnet synchronous machine according to an exemplary embodiment of ;

FIG. 2 is a graph illustrating the determination of the d-axis inductance parameter L according to an exemplary embodiment of _dA schematic flow diagram of (a);

FIG. 3 is a graph illustrating the determination of the q-axis inductance parameter L according to an exemplary embodiment of _qA schematic flow diagram of (a);

FIG. 4 is a schematic flow diagram illustrating the determination of stator resistance Rs according to an exemplary embodiment of ;

fig. 5A illustrates voltage and current waveforms for d-axis inductance parameter identification of a motor according to in an embodiment of the present invention;

fig. 5B illustrates voltage and current waveforms for q-axis inductance parameter identification of a motor according to in an embodiment of the present invention;

fig. 6 shows the voltage waveform and the current waveform when the stator resistance parameter identification is performed on the motor by the method provided by the embodiment of the invention according to the embodiment , and the identification result of the stator resistance Rs;

FIG. 7 illustrates the rotor feedback speed, q-axis current, q-axis voltage, and permanent magnet flux linkage parameter identification results when identifying permanent magnet flux linkages of a motor by the method provided by the embodiment of the invention according to ;

FIG. 8 illustrates a d-axis inductance parameter L identified from a d-axis input voltage signal according to exemplary embodiment_dA functional block diagram of (1);

FIG. 9 illustrates an example of a q-axis input voltage signal identifying a q-axis inductance parameter L according to _qA functional block diagram of (1);

FIG. 10 is a functional block diagram illustrating the identification of the stator resistance Rs for the d-axis input voltage signal in accordance with the exemplary embodiment of ;

FIG. 11 is a functional block diagram illustrating the identification of rotor flux linkage for a q-axis input voltage signal according to an exemplary embodiment of .

Detailed Description

In the following description, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments, however, or more embodiments may be practiced without these details.

Due to the limited restriction of the sampling point of the discrete system, the high-frequency current required by the inductance identification is usually obtained by methods such as FFT (fast Fourier transform), data fitting and the like, is not suitable for rapid engineering application, and becomes a main difficulty for restricting the realization of a parameter identification algorithm. Many researchers have proposed many solutions for offline parameter identification of Permanent Magnet Synchronous motors, but most of these solutions require more complicated data calculation, for example, the document "Self-communication of Permanent Magnet Synchronous Machine drive at standard steady knowledge investors nodes" disclosed in chinese patent CN201610609661.3 and IEEE Transactions on power electronics 2014, 12 th volume 29 th volume 12 th page 2014, 6615 th page 6627, since the controller itself belongs to a discrete system, all current feedback values cannot be acquired, and in order to obtain a high-frequency current peak value, DFT waveforms are adopted to reconstruct the acquired current waveforms in the identification process of dq-axis inductance parameters, which undoubtedly increases the algorithm complexity of the controller, and is also not beneficial to the rapid application of engineering. In addition, the existing offline parameter identification methods are all provided with a PI current controller, and the setting of the PI parameters of the current loop also needs to be carried out according to the inductance and resistance parameters of the controlled motor, so that for the motor with unknown parameters, the setting of the PI parameters of the current loop needs to be carried out according to tests, which inevitably affects the control precision of the current loop, and even affects the parameter identification effect.

In summary, the existing permanent magnet synchronous motor parameter identification method has the following defects that 1, motor parameter identification depends on a current loop controller, 2, inductance identification needs to be performed with complex mathematical calculation, and 3, a current reconstruction algorithm is needed.

Fig. 1 is a schematic flowchart of methods for identifying parameters of a permanent magnet synchronous motor according to an embodiment of , including:

step S101, sequentially inputting a frequency value omega under the set angle of the th_h1Two or more d-axis voltage signals with different amplitudes, and determining a d-axis inductance parameter L according to the frequency value and the amplitude of the d-axis voltage signals and the d-axis current_d。

Step S102, sequentially inputting frequency values omega under a second set angle_h2Two or more q-axis voltage signals with different amplitudes, and determining a q-axis inductance parameter L according to the frequency value and the amplitude of the q-axis voltage signals and the q-axis current_q。

In step S103, the th ramp voltage signal is input to the d-axis, and the stator resistance Rs is determined according to the magnitude of the th ramp voltage signal and the d-axis current.

In the actual operation process, the permanent magnet is determinedD-axis inductance parameter L of magnetic synchronous motor_dQ-axis inductance parameter L_qAnd the order of the stator resistance Rs may be changed, that is, the execution order of steps S101, S102, and S103 may be changed.

The embodiment of the invention can realize the identification of the parameters of the permanent magnet synchronous motor, does not need to construct a speed closed loop and a current closed loop in the identification process of the parameters of the permanent magnet synchronous motor, and has simple structure, simple calculation process and no need of complex data analysis.

determining d-axis inductance parameter L according to frequency value, amplitude value and d-axis current of the d-axis voltage signal_dThe method comprises the following steps:

obtaining d-axis current extreme value i corresponding to d-axis voltage signals with different amplitudes_dmax；

According to the frequency value and the amplitude of the d-axis voltage signal and the d-axis current extreme value i_dmaxDetermining d-axis inductance parameter L_d。

Optionally, in the embodiment of the present disclosure, the input d-axis voltage signal and the q-axis voltage signal are sine voltage signals or cosine voltage signals.

FIG. 2 is a graph illustrating the determination of the d-axis inductance parameter L according to an exemplary embodiment of _dIn step S101, when there are two input d-axis voltage signals, the d-axis inductance parameter L is determined_dThe method comprises the following steps:

step S201, under the set angle of th, the frequency value omega is input_h1Extreme values are U respectively_dh1And U_dh2The d-axis voltage signal of (1).

Step S202, obtaining an extreme value of U_dh1 d-th axis current extreme i_dmax1And extreme value of U_dh2Second d-axis current limit value i of time_dmax2。

Step S203, according to the frequency value omega_h1 d-th axis current limit value i_dmax1And said second d-axis current limit i_dmax2And U_dh1And U_dh2Determining d-axis inductance parameter L_d。

FIG. 8 illustrates a d-axis input voltage signal identifying d-axis power according to Sensing parameter L_dSchematic block diagram of (1). In which, the d-axis voltage is taken as a sinusoidal voltage signal as an example.

Firstly, the motor controller inputs a frequency value omega to the permanent magnet synchronous motor under a set angle of _h1Extreme value of U_dh1Collecting current, and determining the maximum value of the current feedback value as d-axis current extreme value i_dmax1Furthermore, under the condition that the angle of the motor controller is not changed, the input frequency value is not changed, and the extreme value is U_dh2The sinusoidal d-axis voltage signal is acquired, the current is collected, and the maximum value of the current feedback value is determined to be a second d-axis current extreme value i_dmax2Finally, according to d-axis current extreme value i_dmax1And said second d-axis current limit i_dmax2Incremental determination of d-axis inductance parameter L_d。

In embodiments, the d-axis inductance parameter L is determined by the following equation_d：

U_inj1＝U_dh1·sin(ω_h1t)

ω_h1＝2πf₁

U_inj2＝U_dh2·sin(ω_h1t)

Wherein, the f₁Is a voltage signal U_inj1And U_inj2Of (c) is detected. Optionally, f₁The value range of (A) is 800 Hz-1600 Hz. Optionally, f₁The values of (A) are 800Hz, 1000Hz, 1200Hz, 1400Hz and 1600 Hz. The input high-frequency voltage signal is convenient for reducing the discreteness of the current sampling value, the sampled current value is in a cosine form, the identification difficulty is reduced, and the d-axis inductance parameter L is improved_dThe accuracy of the identification.

In embodiments, the input frequency value ω is set at the set angle_h1Extreme values are U respectively_dh1、U_dh2And U_dh3The sinusoidal d-axis voltage signal.

In the specific embodiments of , first, the methodAnd the motor controller inputs a frequency value omega to the permanent magnet synchronous motor at a set angle of _h1Extreme value of U_dh1Collecting current, and determining the maximum value of the current feedback value as d-axis current extreme value i_dmax1Furthermore, under the condition that the angle of the motor controller is not changed, the input frequency value is not changed, and the extreme value is U_dh2The sinusoidal d-axis voltage signal is acquired, the current is collected, and the maximum value of the current feedback value is determined to be a second d-axis current extreme value i_dmax2Thirdly, under the condition that the angle of the motor controller is not changed, the input frequency value is not changed, and the extreme value is U_dh3And collecting the current, and determining the maximum value of the current feedback value as a third d-axis current extreme value i_dmax3Finally, according to d-axis current extreme value i_dmax1Second d-axis current limit i_dmax2And a third d-axis current limit i_dmax3Incremental determination of d-axis inductance parameter L_d。

, determining the d-axis inductance parameter L by the following formula_d：

U_inj1＝U_dh1·sin(ω_h1t)

U_inj2＝U_dh2·sin(ω_h1t)

U_inj5＝U_dh3·sin(ω_h1t)

ω_h1＝2πf₁

Wherein, the f₁Is a voltage signal U_inj1、U_inj2And U_inj5Of (c) is detected. Optionally, f₁The value range of (A) is 800 Hz-1600 Hz. Optionally, f₁The values of (A) are 800Hz, 1000Hz, 1200Hz, 1400Hz and 1600 Hz. The input high-frequency voltage signal is convenient for reducing the discreteness of the current sampling value, the sampled current value is in a cosine form, the identification difficulty is reduced, and the d-axis inductance parameter L is improved_dThe accuracy of the identification.

In embodiments, the rootDetermining a q-axis inductance parameter L according to the frequency value and amplitude of the sinusoidal q-axis voltage signal and the q-axis current_qThe method comprises the following steps:

obtaining q-axis current extreme value i corresponding to q-axis voltage signals with different amplitudes_qmax；

According to the frequency value and the amplitude of the q-axis voltage signal and the extreme value i of the q-axis current_qmaxDetermining a q-axis inductance parameter L_q。

FIG. 3 is a graph illustrating the determination of the q-axis inductance parameter L according to an exemplary embodiment of _qWhen there are two q-axis voltage signals input in step S102, the q-axis inductance parameter L is determined_qThe method comprises the following steps:

step S301, inputting a frequency value omega under a second set angle_h2Extreme values are U respectively_qh1And U_qh2The sinusoidal q-axis voltage signal of (a).

Step S302, obtaining an extreme value of U_qh1Current extreme i of q-axis of time_qmax1And extreme value of U_qh2Second q-axis current extreme i of time_qmax2。

Step S303, according to the frequency value omega_h2 q-axis current limit value i_qmax1And said second q-axis current limit i_qmax2And U_qh1And U_qh2Determining q-axis inductance parameter L_q。

FIG. 9 illustrates a q-axis input voltage signal identifying a q-axis inductance parameter L according to an embodiment _qSchematic block diagram of (1). In this case, the q-axis voltage is taken as a sinusoidal voltage signal.

Firstly, the motor controller inputs a frequency value omega to the permanent magnet synchronous motor under a second set angle_h2Extreme value of U_qh1Collecting current, and determining the maximum value of the current feedback value as q-axis current extreme value i_qmax1Furthermore, under the condition that the angle of the motor controller is not changed, the input frequency value is not changed, and the extreme value is U_qh2The sinusoidal q-axis voltage signal is acquired, the current is collected, and the maximum value of the current feedback value is determined to be a second q-axis current extreme value i_qmax2Finally, according to q-axis current extreme value i_qmax1And stationSecond q-axis current limit i_qmax2Determining q-axis inductance parameter L by incremental means_q。

In embodiments, the q-axis inductance parameter L is determined by the following equation_q：

U_inj3＝U_qh1·sin(ω_h2t)

U_inj4＝U_qh2·sin(ω_h2t)

ω_h2＝2πf₂

Wherein, the f₂Is a voltage signal U_inj3And U_inj4Of (c) is detected. Optionally, f₂The value range of (A) is 800 Hz-1600 Hz. Optionally, f₂The values of (A) are 800Hz, 1000Hz, 1200Hz, 1400Hz and 1600 Hz. The input high-frequency voltage signal is convenient for reducing the discreteness of the current sampling value, the sampled current value is in a cosine form, the identification difficulty is reduced, and the q-axis inductance parameter L is improved_qThe accuracy of the identification.

In embodiments, the frequency value ω is input at a second set angle_h2Extreme values are U respectively_qh1、U_qh2And U_qh3The sinusoidal q-axis voltage signal of (a).

In embodiments, first, the motor controller inputs a frequency value ω to the PMSM at a second set angle_h2Extreme value of U_qh1Collecting current, and determining the maximum value of the current feedback value as q-axis current extreme value i_qmax1Furthermore, under the condition that the angle of the motor controller is not changed, the input frequency value is not changed, and the extreme value is U_qh2The sinusoidal q-axis voltage signal is acquired, the current is collected, and the maximum value of the current feedback value is determined to be a second q-axis current extreme value i_qmax2Thirdly, under the condition that the angle of the motor controller is not changed, the input frequency value is not changed, and the extreme value is U_qh3The sinusoidal q-axis voltage signal is acquired, the current is collected, and the maximum value of the current feedback value is determined to be a third q-axisCurrent extreme i_qmax3Finally, according to q-axis current extreme value i_qmax1Second q-axis current limit i_qmax2And a third q-axis current limit i_qmax3Determining q-axis inductance parameter L by incremental means_q。

, determining the q-axis inductance parameter L by the following formula_q：

U_inj3＝U_qh1·sin(ω_h2t)

U_inj4＝U_qh2·sin(ω_h2t)

U_inj6＝U_qh3·sin(ω_h2t)

ω_h2＝2πf₂

Wherein, the f₂Is a voltage signal U_inj3、U_inj4And U_inj6Of (c) is detected. Optionally, f₂The value range of (A) is 800 Hz-1600 Hz. Optionally, f₂The values of (A) are 800Hz, 1000Hz, 1200Hz, 1400Hz and 1600 Hz. The input high-frequency voltage signal is convenient for reducing the discreteness of the current sampling value, the sampled current value is in a cosine form, the identification difficulty is reduced, and the q-axis inductance parameter L is improved_qThe accuracy of the identification.

Fig. 4 is a schematic flow diagram illustrating the determination of the stator resistance Rs according to the exemplary embodiment of , wherein the step S103 of determining the stator resistance Rs includes:

in step S401, the th ramp voltage signal is input to the d-axis.

Step S402, sampling the th ramp voltage signal and the d-axis current to obtain a sampled ramp voltage U_dkAnd sampling d-axis current i_dk。

Step S403, according to the sampling ramp voltage U_dkAnd sampling d-axis current i_dkThe stator resistance Rs is determined.

In embodiments, first, the motor controller applies a ramp command of d-axis voltages increasing with time to the motor voltage, and the expression for the injected voltage signal is as follows:

wherein the content of the first and second substances,

the magnitude of the injection amplitude is determined by d-axis current feedback to ensure

And the extreme value of the direct-axis current generated by excitation is less than or equal to the rated current of the tested motor.

Further, a direct axis current extreme value i is obtained_dkEstablishing V_x-I_xAnd (3) a curve is obtained, a region with a good linear section is selected, stator resistance identification is carried out, and the expression of the stator resistance Rs obtained through identification is as follows:

wherein N represents the total number of samples; k is a positive integer less than or equal to N.

Fig. 10 is a schematic block diagram illustrating the identification of the stator resistance Rs for the d-axis input voltage signal according to the exemplary embodiment of .

In embodiments, the ramp voltage U is sampled according to the sampling_dkAnd sampling d-axis current i_dkThe stator resistance Rs is determined by linear fitting.

In the foregoing embodiment, in order to prevent the motor from being damaged due to overcurrent after voltage injection, an extreme value of the input voltage signal needs to be controlled, where the extreme value of the voltage signal is determined by a current extreme value, and specifically, the current extreme value is less than or equal to the maximum current that can be borne by the motor under test.

In embodiments, the frequency value ω of the d-axis voltage signal_h1And a frequency value ω of said q-axis voltage signal_h2And the working frequency is greater than the rated working frequency of the permanent magnet synchronous motor.

In embodiments, the d-axis current limit i_dmaxAnd said q-axis current limit i_qmaxAnd the current value is less than or equal to the rated current value of the permanent magnet synchronous motor.

In embodiments, the method further comprises:

the q-axis input second slope voltage signal is used for adjusting the q-axis input voltage signal when the feedback rotating speed of the rotor reaches th set rotating speed W1, so that the feedback rotating speed of the rotor meets th set rotating speed W1 within set time;

determining the average value u of the q-axis voltage in the set time_q1_ ave, q-axis current average i_q1_ ave and rotor feedback speed average value omega_e1_ave；

Inputting a third slope voltage signal into a q shaft, and when the feedback rotating speed of the rotor reaches W2, adjusting the input voltage signal of the q shaft to enable the feedback rotating speed of the rotor to meet a second set rotating speed W2 within set time;

determining the average value u of the q-axis voltage in the set time_q2_ ave, q-axis current average i_q2_ ave and rotor feedback speed average value omega_e2_ave；

According to the voltage average value u_q1_ ave, q-axis current average i_q1_ ave, average value ω of rotor feedback rotation speed_e1_ ave, q-axis voltage average u_q2_ ave, q-axis current average i_q2_ ave, mean value of rotor feedback speed ω_e2_ ave and the stator resistance Rs, identifying the permanent magnet flux linkage

The magnetic linkage of the permanent magnet is identified according to the embodiment

The strategy of (2) is simple and easy without data fitting.

Fig. 11 is a schematic block diagram for identifying the flux linkage of the rotor permanent magnet.

In , when the speed reaches W1, u is accumulated by controlling the q-axis input voltage signal to keep the motor in a set time when the speed keeps an absolute steady state_q，i_qAnd ω_eAnd the cumulative number of times N1 is recorded. For u is paired_q，i_qAnd ω_eThe sum is averaged, and the average values are recorded as u_q1_ave，i_q1_ ave and ω_e1_ ave, which should satisfy the following formula:

u_q1_ave+u_{q_error}＝R_si_q1_ave+ω_e1_aveψ_f

wherein u is_q1_ave，i_q1_ ave and ω_eThe expressions for 1_ ave are:

wherein N1 represents the total number of samples; k is a positive integer less than or equal to N1.

When the speed reaches W2, the motor is kept in the set time of keeping the speed in an absolute steady state by controlling the q-axis input voltage signal, and u is accumulated_q，i_qAnd ω_eAnd the cumulative number of times N2 is recorded. For u is paired_q，i_qAnd ω_eThe sum is averaged, and the average values are recorded as u_q2_ave，i_q2_ ave and ω_e2_ ave, they should satisfy the following formula:

u_q2_ave+u_{q_error}＝R_si_q2_ave+ω_e2_aveψ_f

wherein u is_q2_ave,i_q2_ ave and ω_eThe expressions of 2_ ave are respectively

Wherein N1 represents the total number of samples; k is a positive integer less than or equal to N1.

Identifying permanent magnet flux linkage by

In , the adjusting the q-axis input voltage signal to make the rotor feedback speed meet the th set speed within the set time includes:

after the feedback rotation speed of the rotor reaches W1, controlling the q-axis voltage to maintain the feedback rotation speed of the rotor within a set range taking W1 as a central value; wherein the voltage is determined by the difference between the feedback speed and W1, with the objective of making the feedback speed meet the speed steady state at W1.

Wherein the voltage signal is determined according to the difference between the actual rotating speed feedback and the -th set rotating speed W1, and comprises the following steps:

during the set time, when the feedback rotation speed is lower than the set value W1, the uq voltage increases, and when the feedback rotation speed is higher than the set value W1, the uq voltage decreases. The purpose of this fluctuating voltage is to maintain the motor speed at W1.

In , the adjusting the q-axis input voltage signal so that the rotor feedback speed meets a second set speed W2 within a set time includes:

after the feedback rotation speed of the rotor reaches W2, controlling the q-axis voltage to maintain the feedback rotation speed of the rotor within a set range taking W2 as a central value; wherein the voltage signal is determined by the difference between the feedback speed and W2, the purpose of which is to make the feedback speed meet the speed steady state at W2.

Wherein the voltage signal is determined according to a difference between the actual rotational speed feedback and the second set rotational speed W2, including:

during the set time, when the feedback rotation speed is lower than the set value W2, the uq voltage increases, and when the feedback rotation speed is higher than the set value W2, the uq voltage decreases. The purpose of this fluctuating voltage is to maintain the motor speed at W2. .

In embodiments, the rotor feedback speed is less than the rated speed of the permanent magnet synchronous motor.

In the actual experimental process, in order to verify the effectiveness of the method provided by the invention, surface-mounted permanent magnet synchronous motors are selected as experimental prototypes, and the method provided by the embodiment of the invention is verified, wherein the main specifications of the experimental prototypes comprise 750W of power, and the parameters of stator resistance and dq-axis inductance are obtained by offline measurement of an IM3536 LCR tester of HIOKI company, and the main motor parameters are R_s＝1.055Ω，L_dq2.6mH, rated current 4.5A. The method provided by the method is adopted to identify the stator resistance and the dq axis inductance, and the stator resistance and the dq axis inductance are compared with the measured value measured off line by the IM3536 LCR tester. Fig. 5A shows waveforms of high-frequency voltage and current (with an initial angle of 0 °) during d-axis inductance parameter identification of the surface-mount permanent magnet synchronous motor by the method provided in this embodiment. Fig. 5B shows the waveforms of high-frequency voltage and current (given an initial angle of 90 °) in the q-axis inductance parameter identification process of the surface-mount permanent magnet synchronous motor by the method provided in this embodiment.

In the experimental process, the frequency value of the input voltage is greater than the rated working frequency of the permanent magnet synchronous motor to be tested and less than the Pulse Width Modulation (PWM) carrier frequency. Since a permanent magnet synchronous machine can be considered as an R-L load,

(where ω is_h2 × pi × f), so that the higher the frequency of the injected high-frequency voltage signal is, the more the inductive reactance is occupiedConsidering that the servo controller is a discrete system, and fixed time intervals exist between current sampling points, the injection frequency is too high, which causes distortion of the waveform of the acquired current and voltage, so the selection of the injection frequency is the key for success or failure of the inductance identification, because the acquired current waveform directly determines whether the controller is capable of reconstructing the peak-to-peak value of the current.

In the experimental process, the inductance identification is carried out by an incremental method, the dq-axis current and voltage do not need to be accurately tracked, the peak-peak value of the dq-axis current does not need to be fitted, and the allowable selected injection frequency range is wider. As can be seen from the partial enlarged view of the voltage and current in fig. 5A, the waveforms of the voltage and current are distorted to different degrees due to the high injection frequency (1.6 kHz). By the proposed method, for FIG. 5A, i is obtained_dmax1＝0.468A，i_dmax2＝0.779A，U_dh2-U_dh1Approximately equal to 8V, thus obtaining L_dFor fig. 5B, i can be obtained as 2.58mH_qmax1＝0.471A，i_qmax2＝0.764A，U_qh2-U_qh1≈8V，L_q2.73 mH. Compared with an offline measured value with a smaller error of 2.6mH, the inductance identification method is proved to be effective.

Fig. 6 shows the voltage waveform and the current waveform during the stator resistance parameter identification of the motor to be tested by the method provided by the embodiment of the invention, and the measurement result of the stator resistance Rs, considering that the rated current of the motor is 4.5A, therefore, the current obtained by the excitation of the injected d-axis voltage does not exceed current, and through fig. 6, the resistance identification should be performed by selecting the part with better current and voltage linearity, namely, the link with higher current, so that 70% -90% of the rated current is selected as the identification interval in the invention, the finally obtained identification result is 1.11 Ω, compared with the offline measurement value (1.055 Ω), the error is smaller, and the stator resistance identification of the invention is proved to be effective.

FIG. 7 shows the result of identifying the rotor feedback speed, q-axis current, q-axis voltage, and permanent magnet flux linkage parameters when identifying the permanent magnet flux linkage of the motor by the method provided by the embodiment of the invention, wherein W1 is 300r/min (corresponding to the electrical angular velocity ω_e125.6rad/s) and W2 of 500r/min (corresponding to an electrical angular velocity ω_e209.33rad/s), the finally obtained flux linkage identification result is 0.137Wb, and compared with the offline measurement result (0.139Wb), the error is smaller, so that the flux linkage identification is proved to be effective.

The scope of the embodiments of the present disclosure includes the full range of claims including the full range of equivalents of the claims, the words used in this application are used only to describe embodiments and not to limit the claims, as used in the description of the embodiments and claims, the singular forms "" (a), "" (an) and "the" (the) are intended to include the plural forms as well, and similarly, the terms "and/or" as used in this application are intended to include or of the above-listed elements and any element or elements listed in association with each other (unless the context clearly indicates otherwise, if there is no limitation in the presence of such elements or elements, the word or elements in the other embodiments and the description of the claims, the word or elements may be included in the other embodiments and/or elements, such elements may be included in the other embodiments and/or excluded from the description, or may be included in the other embodiments and/or excluded from the description of the other embodiments and/or other embodiments, the word or element or elements may be excluded from the other embodiments and/or other embodiments may include the same or other elements.

Those of skill in the art would appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software may depend upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosed embodiments. It can be clearly understood by the skilled person that, for convenience and brevity of description, the specific working processes of the system, the apparatus and the unit described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In the description corresponding to the flowcharts and block diagrams in the figures, operations or steps corresponding to different blocks may also occur in different orders than disclosed in the description, and sometimes there is no specific order between the different operations or steps. For example, two sequential operations or steps may in fact be executed substantially concurrently, or they may sometimes be executed in the reverse order, depending upon the functionality involved. Each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.