阅读说明：本技术 同步磁阻电机自适应调节无传感器控制方法 (Self-adaptive adjustment sensorless control method for synchronous reluctance motor ) 是由 徐殿国 李成睿 王高林 张国强 赵楠楠 于 2020-06-09 设计创作，主要内容包括：一种同步磁阻电机自适应调节无传感器控制方法,属于电机控制技术领域。本发明针对现有同步磁阻电机无位置传感器控制中,零低速运行时采用的高频信号注入法在电机负载较大时存在损耗较大及观测精度降低的问题。包括在同步磁阻电机运行过程中,向其dq轴系注入高频脉冲电压信号；由abc三相轴系下的三相脉冲电流信号得到dq轴系下的电流信号；由dq轴系下的电流信号计算得到转子位置估计误差θ<Sub>err</Sub>,再进一步得到转子估计位置<Image he="77" wi="54" file="DDA0002531400750000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>与转子估计转速<Image he="74" wi="90" file="DDA0002531400750000012.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>同时计算得到高频脉冲电压信号的当前注入电压幅值,使高频脉冲电压信号的幅值按所述当前注入电压幅值进行自适应调整,频率与相位随机,再注入到所述dq轴系中。本发明用于实现电机的无传感器控制。(A synchronous reluctance motor self-adaptive adjustment sensorless control method belongs to the technical field of motor control. The invention aims at the problems of large loss and low observation precision when the motor load is large in the high-frequency signal injection method adopted in zero low-speed operation in the control of the existing synchronous reluctance motor without a position sensor. Injecting a high-frequency pulse voltage signal into a dq shafting of a synchronous reluctance motor in the operation process of the synchronous reluctance motor; obtaining a current signal under a dq shafting from a three-phase pulse current signal under an abc three-phase shafting; calculating to obtain a rotor position estimation error theta from a current signal under a dq shafting err And further obtaining the estimated position of the rotor And estimated rotor speed And meanwhile, calculating to obtain the current injection voltage amplitude of the high-frequency pulse voltage signal, so that the amplitude of the high-frequency pulse voltage signal is adaptively adjusted according to the current injection voltage amplitude, and the frequency and the phase are random and then injected into the dq shafting. The invention is used for realizing the sensorless control of the motor.)

1. A synchronous reluctance motor self-adaptive adjustment sensorless control method is characterized by comprising the following steps:

in the operation process of the synchronous reluctance motor, injecting a high-frequency pulse voltage signal into a dq shafting of the synchronous reluctance motor;

then extracting and converting three-phase pulse current signals of the synchronous reluctance motor abc under a three-phase shaft system to obtain current signals under a dq shaft system;

calculating the current signal under the dq shafting to obtain the rotor position estimation error theta_err(ii) a Error theta is estimated for rotor position_errPI regulation is carried out to make the value of the PI regulation zero to obtain the estimated position of the rotor

and meanwhile, calculating a current signal under the dq shafting to obtain the current injection voltage amplitude of the high-frequency pulse voltage signal, and enabling the amplitude of the high-frequency pulse voltage signal to be adaptively adjusted according to the current injection voltage amplitude, wherein the frequency and the phase are random, and then injecting the high-frequency pulse voltage signal into the dq shafting.

2. The adaptive-tuning sensorless control method of a synchronous reluctance motor according to claim 1,

the high-frequency pulse voltage signal comprises a high-frequency square wave voltage signal, and the obtaining method comprises the following steps:

in the formula (I), the compound is shown in the specification,

3. The adaptive-tuning sensorless control method of the synchronous reluctance motor according to claim 2,

and three-phase pulse current signals of the synchronous reluctance motor abc under the three-phase shaft system are converted by clark and park to obtain current signals under the dq shaft system.

4. The adaptive-tuning sensorless control method of a synchronous reluctance motor according to claim 3,

the rotor position estimation error θ_errThe obtaining method comprises the following steps:

for the current signal under the dq axis system

Wherein

In the formula L_qhFor q-axis stator inductance, M, of synchronous reluctance machines_hIs a synchronous reluctance motor mutual inductance; l is_dhFor d-axis stator inductance, T, of synchronous reluctance machines_sFor PWM period, gamma_d2Is a second demodulated signal;

L₂＝(L_d-L_q)/2，

L_dis d-axis inductance, L, of a synchronous reluctance motor_qIs a q-axis inductor of a synchronous reluctance motor.

5. The adaptive-tuning sensorless control method of the synchronous reluctance motor according to claim 4,

the rotor position estimation error θ_errThe calculating method comprises the following steps:

according to the dq shafting equation of the synchronous reluctance motor:

in the formula u_dFor d-axis stator voltage of the machine, u_qFor the motor q-axis stator voltage, i_dFor d-axis stator currents of the machine, i_qIs the motor q-axis stator current; r_sIs stator resistance, ω_eThe electrical speed of the motor; p is derivation;

when the synchronous reluctance motor is lower than the rated rotating speed by 10 percent or is static and the amplitude of the high-frequency pulse voltage is higher than a set threshold, the shafting equation is simplified as follows:

and deforming the simplified shafting equation to be below a measurement shafting:

in the formula L₁＝(L_d+L_q)/2，

θ_m＝arctan[2M_h/(L_dh-L_qh)]；

In order to measure the d-axis high-frequency current signal under the shafting,measuring a q-axis high-frequency current signal under a shafting;

when rotor position estimation error theta_errWhen the angle is within 5 degrees, the equation under the measuring shaft system is simplified to obtain the rotor position estimation error theta_err：

6. The adaptive-tuning sensorless control method of a synchronous reluctance motor according to claim 5,

error theta is estimated for rotor position_errPerforming PI regulation to obtain the estimated rotation speed of the rotor

7. The adaptive-regulation sensorless control method of the synchronous reluctance motor according to claim 6, wherein the estimated rotor position is determined by a rotor position estimation method

setting the rotor to a given speed omega_refAnd estimated rotor speed

the dq-axis current feedback

8. The adaptive-tuning sensorless control method of the synchronous reluctance motor according to claim 7,

the method for obtaining the current injection voltage amplitude of the high-frequency pulse voltage signal comprises the following steps:

feeding back the d-axis high-frequency current

9. The synchronous reluctance motor amplitude adaptive adjustment based high-frequency signal injection sensorless control method according to claim 8, wherein:

the method for randomly selecting the frequency and the phase of the high-frequency square wave voltage signal comprises the following steps:

four high-frequency square wave voltage signals are adopted, and respectively have two groups of frequencies, wherein each group of frequencies has two groups of phases of 90 degrees and 270 degrees, and the injection voltage is defined as follows:

in the formula u_kFor the k-th period, a voltage signal is injected_sIs a frequency, phase random square wave signal, T_iIs a unit period of the injection signal; the T is_iAnd T_ΣSatisfies the following conditions: t is_Σ＝T_iOr T_Σ＝2T_i。

Technical Field

The invention relates to a self-adaptive adjustment sensorless control method for a synchronous reluctance motor, and belongs to the technical field of motor control.

Background

The synchronous reluctance motor has higher and higher competitiveness in the field of industrial driving, and can replace an induction motor, a permanent magnet synchronous motor and the like which are widely applied at present in some application fields with low cost and severe working environment due to the characteristics of low cost and strong robustness. The most widely applied vector control mode in the current industrial field needs motor rotor position information to be used in control processes such as current signal decoupling, the position sensor-free control technology can solve the problems of extra cost, reliability reduction and the like caused by application of a position sensor, and the method is a main research direction in the current motor control field.

Currently, more and more application fields put new demands on sensorless control of motors in low-speed operation, such as mine car driving motors, cutting machines, wire drawing machines, and the like. The position sensorless technology adopted when the synchronous reluctance motor runs at zero and low speed mainly adopts a high-frequency signal injection method, and the position of the rotor is determined by extracting salient pole characteristic information of the motor. The conventional high frequency signal injection method is mainly classified into a high frequency rotating voltage injection method, a high frequency pulsating voltage injection method, and a high frequency square wave voltage injection method. In contrast, the principle of the hf pulsating voltage injection method is simpler and has less torque ripple, and thus is more widely used, but still requires the use of a filter; the high-frequency square wave voltage injection method does not need to use a filter, and the frequency of the voltage signal can be selected to be higher, so that the control performance is more excellent. However, the injection signal frequency is high, which brings extra high-frequency noise to the driving system and limits the application of the high-frequency square wave voltage injection method in the actual industrial field. The random high-frequency square wave signal injection method adopted at present converts discrete components in the phase current PSD of the motor into continuous components, and can reduce high-frequency noise caused by voltage injection. However, due to the characteristic that the parameters of the synchronous reluctance motor change greatly with the load, the constant amplitude high frequency voltage injection method has the problems of current noise pollution, and when the motor runs under a high load condition, the loss caused by injection is particularly prominent, and the torque pulsation caused by injection can cause the accuracy of rotor position estimation to be reduced, so that the practicability of the scheme is reduced, and the wide application of the scheme is limited.

Therefore, in order to improve the practicability of the sensorless technology, the research on the sensorless control strategy of the zero-low-speed synchronous reluctance motor with low noise and low loss has important theoretical significance and application value.

Disclosure of Invention

The invention provides a synchronous reluctance motor self-adaptive adjustment sensorless control method, aiming at the problems of large loss and low observation precision when a motor load is large by adopting a high-frequency signal injection method during zero and low speed operation in the existing synchronous reluctance motor sensorless control.

The invention discloses a synchronous reluctance motor self-adaptive adjustment sensorless control method, which comprises the following steps:

in the operation process of the synchronous reluctance motor, injecting a high-frequency pulse voltage signal into a dq shafting of the synchronous reluctance motor;

then extracting and converting three-phase pulse current signals of the synchronous reluctance motor abc under a three-phase shaft system to obtain current signals under a dq shaft system;

calculating the current signal under the dq shafting to obtain the rotor position estimation error theta_err(ii) a Error theta is estimated for rotor position_errPI regulation is carried out to make the value of the PI regulation zero to obtain the estimated position of the rotor

And estimated rotor speedThe synchronous reluctance motor is used for the closed-loop control of the rotating speed and the current of the synchronous reluctance motor;

and meanwhile, calculating a current signal under the dq shafting to obtain the current injection voltage amplitude of the high-frequency pulse voltage signal, and enabling the amplitude of the high-frequency pulse voltage signal to be adaptively adjusted according to the current injection voltage amplitude, wherein the frequency and the phase are random, and then injecting the high-frequency pulse voltage signal into the dq shafting.

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

the high-frequency pulse voltage signal comprises a high-frequency square wave voltage signal, and the obtaining method comprises the following steps:

in the formula (I), the compound is shown in the specification,a d-axis high-frequency square wave voltage signal injected into the stator of the synchronous reluctance motor,

injecting a q-axis high-frequency square wave voltage signal into a stator of the synchronous reluctance motor; u shape_injIs the reference amplitude of the high frequency square wave voltage signal,is a unit amplitude random square wave voltage signal; wherein T is the injection voltage time, T_ΣIn order to inject the voltage period, the voltage is injected,is the injection voltage phase.

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

and three-phase pulse current signals of the synchronous reluctance motor abc under the three-phase shaft system are converted by clark and park to obtain current signals under the dq shaft system.

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

the rotor position estimation error θ_errThe obtaining method comprises the following steps:

for the current signal under the dq axis system

Carrying out high-pass filtering to obtain a d-axis high-frequency current feedback value

And q-axis high-frequency current feedback value

Feeding back the d-axis high-frequency current

And q-axis high-frequency current feedback value

Obtaining the dq axis high-frequency current under the measuring shafting after transforming to the measuring shafting

And then the first demodulation signal gamma_d1Multiplying to obtain demodulated d-axis high-frequency currentAnd demodulated q-axis high frequency current

And multiplying by a coupling coefficient lambdaAfter subtraction, the difference value is related to the motor parameter coefficient K₃Multiplying to obtain the rotor position estimation error theta_err；

Wherein

In the formula L_qhFor q-axis stator inductance, M, of synchronous reluctance machines_hIs a synchronous reluctance motor mutual inductance; l is_dhFor d-axis stator inductance, T, of synchronous reluctance machines_sFor PWM period, gamma_d2Is a second demodulated signal;

L₂＝(L_d-L_q)/2，

L_dis d-axis inductance, L, of a synchronous reluctance motor_qIs a q-axis inductor of a synchronous reluctance motor.

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

the rotor position estimation error θ_errThe calculating method comprises the following steps:

according to the dq shafting equation of the synchronous reluctance motor:

in the formula u_dFor d-axis stator voltage of the machine, u_qFor the motor q-axis stator voltage, i_dFor d-axis stator currents of the machine, i_qIs the motor q-axis stator current; r_sIs stator resistance, ω_eThe electrical speed of the motor; p is derivation;

when the synchronous reluctance motor is lower than the rated rotating speed by 10 percent or is static and the amplitude of the high-frequency pulse voltage is higher than a set threshold, the shafting equation is simplified as follows:

and deforming the simplified shafting equation to be below a measurement shafting:

in the formula L₁＝(L_d+L_q)/2，

θ_m＝arctan[2M_h/(L_dh-L_qh)]；

In order to measure the d-axis high-frequency current signal under the shafting,

measuring a q-axis high-frequency current signal under a shafting;

when rotor position estimation error theta_errWhen the angle is within 5 degrees, the equation under the measuring shaft system is simplified to obtain the rotor position estimation error theta_err：

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

error theta is estimated for rotor position_errPerforming PI regulation to obtain the estimated rotation speed of the rotor

Error theta is estimated for rotor position_errIntegrating after PI adjustment to obtain the estimated position of the rotor

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

rotor estimated positionAnd estimated rotor speedThe closed-loop control of the rotating speed and the current for the synchronous reluctance motor comprises the following steps:

setting the rotor to a given speed omega_refAnd estimated rotor speed

Making difference to obtain rotation speed error signal, and obtaining dq axis current set after PI regulationAnd dq axis current feedback

Subtracting and obtaining dq axis given voltage through PI

And then d-axis high frequency voltageAfter addition, voltage setting under αβ shafting is obtained through ipark transformation

Obtaining final output voltage through an SVPWM link, and controlling the synchronous reluctance motor;

the dq-axis current feedbackFrom current signals in dq axis system

And low-pass filtering to obtain the final product.

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

the method for obtaining the current injection voltage amplitude of the high-frequency pulse voltage signal comprises the following steps:

feeding back the d-axis high-frequency currentAnd q-axis high-frequency current feedback valueAnd a second demodulation signal gamma_d2Multiplying to obtain the variation

Calculating absolute value and then calculating the given valueComparing, and adjusting the difference value obtained by subtraction by a PI regulator to obtain an injection voltage amplitude signal U_inj(ii) a The parameters of the PI regulators are respectively k_{p_hf}，T_hf。

According to the self-adaptive adjustment sensorless control method of the synchronous reluctance motor of the invention,

the method for randomly selecting the frequency and the phase of the high-frequency square wave voltage signal comprises the following steps:

four high-frequency square wave voltage signals are adopted, and respectively have two groups of frequencies, wherein each group of frequencies has two groups of phases of 90 degrees and 270 degrees, and the injection voltage is defined as follows:

in the formula u_kFor the k-th period, a voltage signal is injected_sIs a frequency, phase random square wave signal, T_iIs a unit period of the injection signal; the T is_iAnd T_ΣSatisfies the following conditions: t is_Σ＝T_iOr T_Σ＝2T_i。

The invention has the beneficial effects that: the method is based on amplitude self-adaptive adjustment high-frequency signal injection, and injects high-frequency pulse voltage with random frequency and phase and self-adaptive adjustment amplitude into a d-axis system of a synchronous reluctance motor in the operation process of the synchronous reluctance motor; according to current information fed back under a dq shaft system measured by the synchronous reluctance motor, carrying out current differential calculation on the dq shaft and coupling by using coupling parameters to obtain a position estimation error signal of a rotor; then, the position estimation error signal of the rotor is adjusted to be zero by utilizing PI control, the position and the rotating speed of the rotor are obtained and are used for closed-loop control of the rotating speed and the current of the motor, and the control without a position sensor is realized; and finally, carrying out self-adaptive adjustment by using the amplitude of the feedback d-axis high-frequency current signal to obtain the amplitude of the injection voltage, and ensuring the amplitude of the d-axis high-frequency current signal to be constant.

Under the condition of ensuring the normal operation of a permanent magnet synchronous motor position sensorless system, the method adopts a mode of injecting a high-frequency voltage signal with the amplitude value self-adaptively adjusted by a d axis, so that the noise pollution and the loss caused by the injection of the high-frequency signal are greatly reduced (through experimental verification, the output power result shows that under the operating condition of full load and 150r/min, the loss caused by the injection is reduced by 77 percent, the high-frequency noise is measured by current power density, and compared with the traditional injection method, the high-frequency noise is reduced by 40dB near the injection frequency), and the practicability of the method is improved.

Compared with the traditional high-frequency signal injection method, the method disclosed by the invention has the advantages that the high-frequency voltage with the amplitude value capable of being adjusted in a self-adaptive manner is injected in the d axis, the extra power loss and high-frequency noise generated in the traditional method can be effectively reduced, and the application value of the position-free sensor is improved.

The signal injection method of the invention realizes the position-sensorless control strategy of self-adaptive adjustment of high-frequency signal injection based on the amplitude value under the zero low speed of the synchronous reluctance motor, effectively reduces noise pollution, torque pulsation and power loss, improves the position observation accuracy and improves the practicability of the position-sensorless technology.

The method can carry out vector control on the synchronous reluctance motor without using a position sensor, can detect the position and rotating speed information of the rotor by superposing a high-frequency voltage signal on the motor voltage, and is used for closed-loop control of the motor. Compared with the traditional high-frequency signal method, the method adopted by the invention can effectively reduce the loss caused by the injected signal, and simultaneously, because the injection amplitude is reduced under the heavy load condition, the high-frequency noise and the torque fluctuation caused by injection can be reduced, the position observation accuracy is improved, and the use value of the position-free sensor is greatly improved.

Drawings

FIG. 1 is an overall block diagram of the synchronous reluctance machine adaptive tuning sensorless control method of the present invention; in the figure, SVPWM is a space vector modulation module, and SynRM is a synchronous reluctance motor;

FIG. 2 is a schematic diagram of the injection of high frequency pulse voltage and excitation current and demodulation signal in the method of the present invention; in the figure, PWMPdriod is a PWM period;

FIG. 3 is a waveform of an experiment using the method of the present invention when the motor is loaded to a rated load at a low speed of 150 rpm; sequentially obtaining an actual position waveform of the rotor, an estimation error waveform of the rotor position and a phase current waveform from top to bottom; (ii) a

FIG. 4 is a waveform of the operation of the motor at low speed of 150 rpm under different load conditions using a conventional random high frequency voltage injection method; wherein (a) is a d-axis high-frequency current and rotor position estimation error graph; (b) is a power density spectrum (PSD) graph of the current under full load, (c) is a Fourier analysis (FFT) graph of the current under full load;

FIG. 5 is a waveform of a synchronous reluctance machine operating at low speed of 150 rpm under different load conditions using the method of the present invention; wherein (a) is a d-axis high-frequency current and rotor position estimation error graph; (b) is a power density spectrum (PSD) graph of the current under full load, (c) is a Fourier analysis (FFT) graph of the current under full load;

fig. 6 shows the percentage reduction of the extra loss caused by the injection compared to the conventional high frequency injection method for different rotation speeds and different loads.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

The invention is further described with reference to the following drawings and specific examples, which are not intended to be limiting.