CN113676106B - A Positionless Method for High Frequency Injection in Double Windings for Six-Phase Permanent Magnet Motors - Google Patents

Abstract

The invention discloses a position-sensor-free control method for pulse vibration high-frequency injection of a double-set winding of a six-phase permanent magnet motor, which divides the six-phase permanent magnet motor into two sets of windings for control; injecting high-frequency signals with the phase difference of 90 degrees into an estimated d-axis of the first set of windings and an estimated q-axis of the second set of windings, calculating six-phase voltages, solving zero-sequence voltages, converting the zero-sequence voltages, and inputting the converted zero-sequence voltages into a low-pass filter; finally, inputting the filtering result into a PI link and an integration link to obtain an estimated position of the motor rotor; according to the invention, the six-frequency interference problem existing in the traditional pulse vibration high-frequency injection method is solved by respectively injecting high-frequency signals into the estimated coordinate systems of the two sets of windings so that the signals entering the PI regulator do not have the six-frequency interference signals; and secondly, high-frequency signals are respectively injected, so that the torque pulsation and the rotation speed fluctuation of a pulse vibration high-frequency injection algorithm of the rotation comprehensive vector can be reduced, the accuracy of rotor position identification can be effectively improved, and the torque pulsation is reduced.

Description

A Position-Free Method for High Frequency Injection of Double Windings in Six-Phase Permanent Magnet Motors

Technical Field

The invention relates to the technical field of motor control, and mainly to a position sensorless control method for double-set winding pulse high-frequency injection of a six-phase permanent magnet motor.

Background Art

The six-phase permanent magnet motor drive system is widely used in the fields of ship electric propulsion, locomotive power traction, hybrid vehicles and more electric aircraft. The permanent magnet motor drive system using positionless technology can reduce the size and cost of the system.

Existing position sensorless technologies are divided into two categories, namely, position sensorless control technologies based on back-EMF and salient pole effect. Since the motor has no extended back-EMF at zero speed and the back-EMF harmonic component is large at low speed, it is difficult to accurately estimate the rotor position using the back-EMF observer method at zero and low speed. The position sensorless control method based on salient pole effect mainly uses the non-ideal characteristics of the motor itself to estimate the motor's speed and position signals. Since physical quantities such as back-EMF that are subject to speed constraints are not used, it also has good performance at zero and low speed.

As a position sensorless control method based on the salient pole effect, the high-frequency signal injection method has the basic principle of injecting a certain high-frequency signal into the motor winding, detecting the signal feedback value containing the rotor position information, and then obtaining the motor rotor angle. This method is simple to implement, has good robustness, and has no additional requirements for system hardware. The pulse high-frequency injection method injects a high-frequency sinusoidal voltage signal into the direct axis d-axis of the synchronous rotating coordinate system. The injected signal will form a high-frequency pulse voltage signal in the stationary coordinate system. After amplitude modulation of the quadrature-axis high-frequency current signal, the information related to the rotor position can be extracted, thereby obtaining the rotor position and speed information.

Since the zero-sequence voltage amplitude does not depend on the frequency of the injection signal, the position sensorless control based on high-frequency injection of zero-sequence voltage can significantly improve the system robustness and position estimation accuracy. However, for the pulsating high-frequency voltage injection method based on zero-sequence voltage, in the process of calculating the error between the actual value and the estimated value of the rotor position, a six-fold frequency disturbance (the frequency of the disturbance is six times the electrical angular frequency of the motor) is introduced, thereby affecting the identification accuracy of the rotor position.

In order to solve the interference problem of sextuple frequency disturbance, the patent "A method for estimating the position of a permanent magnet motor based on pulse high-frequency injection of a rotating integrated vector (202110675485.4)" proposes a pulse high-frequency injection method of a rotating integrated vector. This method injects a rotating high-frequency voltage signal into the estimated synchronous rotating coordinate system, which can well suppress the sextuple frequency disturbance. However, the high-frequency voltage signal of the rotating vector injected by this method produces large torque pulsation and speed fluctuation in the motor.

Summary of the invention

Purpose of the invention: In order to solve the problems existing in the above-mentioned background technology, the present invention provides a position sensorless control method for double-winding pulse high-frequency injection of a six-phase permanent magnet motor, which suppresses the interference problem of the sixth-frequency disturbance and reduces the torque pulsation and speed fluctuation in the existing pulse high-frequency injection method based on the rotating integrated vector.

Technical solution: To achieve the above purpose, the technical solution adopted by the present invention is:

A position sensorless control method for double winding pulse high frequency injection of a six-phase permanent magnet motor, the six-phase permanent magnet motor winding is divided into two independent windings, wherein A, B, C are the first winding, and X, Y, Z are the second winding;

的差值

输入至第一PI环节，获得电机的给定q轴电流i_q ^*；将给定q轴电流i_q ^*和实际q轴电流i_{q_set1}的差值i_q ^*-i_{q_set1}输入至第二PI环节，得到u^* _{q_set1}；设定给定d轴电流i^* _{d_set1}，将给定d轴电流i^* _{d_set1}和实际d轴电流i_{d_set1}的差值i^* _{d_set1}-i_{d_set1}输入至第二PI环节，得到u^* _{d_set1}；对u^* _{d_set1}注入高频电压U_hcosω_ht获得u^* _{d_set1}+U_hcosω_ht，对u^* _{d_set1}+U_hcosωt和u^* _{q_set1}进行dq/abc变换，得到对应逆变器A，B，C相桥臂的占空比；The three-phase currents i _a , i _b , i _c of the first set of windings of the motor are obtained by current sensors, and abc/dq transformation is performed on i _a , i _b , i _c to obtain the actual q-axis current i _{q_set1} and d-axis current i _{d_set1} of the first set of windings; the given motor electrical angular frequency ω ^* is compared with the estimated electrical angular frequency

The difference

Input into the first PI link to obtain the given q-axis current i _q ^* of the motor; input the difference i _q ^* -i _{q_set1} between the given q-axis current i _q ^* and the actual q-axis current i _{q_set1} into the second PI link to obtain u ^* _{q_set1} ; set the given d-axis current i ^* _{d_set1} , and input the difference i ^* _{d_set1} -i _{d_set1} between the given d-axis current i ^* _{d_set1} and the actual d-axis current i _{d_set1} into the second PI link to obtain u ^* _{d_set1} ; inject high-frequency voltage U _h cosω _h t into u ^* _{d_set1} to obtain u ^* _{d_set1} +U _h cosω _h t, perform dq/abc transformation on u ^* _{d_set1} +U _h cosωt and u ^* _{q_set1} to obtain the duty cycle of the corresponding inverter A, B, and C phase bridge arms;

Similarly, the three-phase currents i _x , i _y , i _z of the second set of windings of the motor are obtained through the current sensor, and abc/dq transformation is performed on i _x , i _y , i _z to obtain the actual q-axis current i _{q_set2} and d-axis current i _{d_set2} of the second set of windings; the difference i _q ^* -i _{q_set2} between the given q-axis current i _q ^* and the actual q-axis current i _{q_set2} is input to the second PI link to obtain u ^* _{q_set2} ; the given d-axis current i ^* _{d_set2} is set, and the difference i ^* _{d_set2} -i _{d_set2} between the given d-axis current i ^* _{d_set2} and the actual d- ^axis current i _{d_set2} is input _to the second PI link to obtain u ^* _{d_set2} ; the high-frequency voltage U _{h sinω h} t is injected into u ^* _{q_set2} to obtain u ^* _{q_set2} +U _h sinω _{h t} ; t and u ^* _{d_set2} are transformed by dq/abc to obtain the duty cycle of the corresponding inverter X, Y, and Z phase bridge arms; two independent high-frequency signals are introduced and injected into the estimated reference coordinate systems of the first set of windings and the second set of windings of the six-phase motor respectively to estimate the motor rotor position. The specific steps are as follows:

注入电机第一套绕组的估计参考坐标系，将

注入电机第二套绕组的估计参考坐标系，并分别求解各相电压如下，其中U_h为注入高频信号的幅值，ω_h为注入高频信号的频率：Step S1: For the first set of windings,

Inject the estimated reference frame of the first set of motor windings into

The estimated reference coordinate system of the second set of motor windings is injected, and the phase voltages are solved as follows, where _Uh is the amplitude of the injected high-frequency signal and _ωh is the frequency of the injected high-frequency signal:

其中

为实际的d轴位置与估计的d轴位置之间的差值；Where _L0 is the average value of the motor self-inductance, _M0 is the average value of the motor mutual inductance, _Ld is the motor d-axis inductance, _Lq is the motor q-axis inductance,

in

is the difference between the actual d-axis position and the estimated d-axis position;

Step S2: According to the above-obtained phase voltages, the zero-sequence voltage is obtained as follows:

Step S3, transform the zero-sequence voltage as follows:

The transformation result is input into a low-pass filter for filtering to obtain:

Where k is the filter coefficient;

Step S4, inputting the low-pass filtering result into the PI adjustment link to obtain the estimated electrical angular frequency of the motor, and inputting the estimated electrical angular frequency into the integration link to obtain the estimated position of the motor rotor.

后各相电压求解如下：Furthermore, in step S1, the first set of windings is injected with a voltage signal

The voltage of each phase is then solved as follows:

产生的dq轴电流的变化率为：Step L1.1: The first set of windings is injected

The resulting rate of change of the dq axis current is:

产生的三相电流变换率如下：Step L1.2: Calculate

The resulting three-phase current conversion rate is as follows:

产生的三相电压如下：Step L1.3: Calculate

The three-phase voltages generated are as follows:

后各相电压求解如下：For the second winding, the injected voltage signal

The voltage of each phase is then solved as follows:

后产生的dq轴电流的变化率为：Step M1.1: The second set of windings is injected

The change rate of the dq axis current generated is:

产生的三相电流变换率如下：Step M1.2: Calculate

The resulting three-phase current conversion rate is as follows:

产生的三相电压如下：Step M1.3: Calculate

The three-phase voltages generated are as follows:

Beneficial effects:

(1) The solution proposed by the present invention controls the six-phase motor winding by dividing it into two windings and injecting two independent high-frequency voltage signals into the two independent windings, so that there is no six-fold frequency interference signal in the signal entering the PI regulator, thereby solving the six-fold frequency interference problem existing in the traditional high-frequency injection method;

(2) In the solution proposed by the present invention, the high-frequency voltage signal is injected only into the q-axis of the second set of winding estimation coordinate system, and the torque pulsation is reduced to half of the pulsation high-frequency injection method based on the rotating comprehensive vector, thereby effectively reducing the torque pulsation and speed fluctuation.

(3) The solution proposed in the present invention can effectively improve the accuracy of rotor position identification and reduce torque pulsation and speed fluctuation.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a flow chart of position sensorless control for high frequency pulse injection of double windings for a six-phase permanent magnet motor provided by the present invention;

FIG2 is a block diagram of a conventional six-phase permanent magnet motor speed control;

FIG3 is a block diagram of a conventional position-free control method for a six-phase permanent magnet motor based on pulse high-frequency injection;

FIG4 is a waveform diagram of the rotor position and error in a conventional six-phase permanent magnet motor position-free method based on pulse high-frequency injection;

FIG5 is a control block diagram of a six-phase permanent magnet motor position-free method proposed in the patent “A method for estimating the position of a permanent magnet motor based on pulse high-frequency injection of a rotating integrated vector”;

FIG6 is a diagram showing the rotor position and error waveform of a six-phase permanent magnet motor position-free method based on pulse high-frequency injection of a rotating integrated vector;

FIG7 is a torque waveform diagram of a six-phase permanent magnet motor position-free method based on pulse high-frequency injection of a rotating integrated vector;

8 is a control block diagram of a position sensorless control method for double winding pulsation high frequency injection for a six-phase permanent magnet motor proposed by the present invention;

9 is a diagram showing rotor position and error waveforms of the position sensorless control method proposed by the present invention;

FIG. 10 is a torque waveform diagram of the position sensorless control method proposed in the present invention.

DETAILED DESCRIPTION

The present invention will be further described below in conjunction with the accompanying drawings.

The present invention aims at the interference problem of sextuple frequency disturbance quantity existing in the control of six-phase permanent magnet motor and the problems of torque pulsation and speed fluctuation in the existing pulse high frequency injection method based on rotating comprehensive vector, and proposes a position sensorless control method for double winding pulse high frequency injection of six-phase permanent magnet motor. The following respectively provides the position sensorless control method of six-phase permanent magnet motor based on pulse high frequency injection in the prior art and the position estimation method of permanent magnet motor based on pulse high frequency injection of rotating comprehensive vector in the existing patent, and the position sensorless control method for double winding pulse high frequency injection of six-phase permanent magnet motor provided by the present invention, and provides three specific embodiments, and compares and explains them to specifically prove the superiority of the position sensorless control method provided by the present invention.

1. Position sensorless control method of six-phase permanent magnet motor based on pulse high-frequency injection.

的差值

输入至第一PI环节，获得电机的给定q轴电流i_q ^*，通过电流传感器获取电机的六相电流i_a，i_b，i_c，i_d，i_e和i_f，对i_a，i_b，i_c，i_d，i_e和i_f进行abcdef/dq变换，获得实际q轴电流i_q和d轴电流i_d；将给定q轴电流i_q ^*和实际q轴电流i_q的差值i_q ^*-i_q输入至第二PI环节，得到u^* _q；设定给定d轴电流i^* _d，将给定d轴电流i^* _d和实际d轴电流i_d的差值i^* _d-i_d输入至第二PI环节，得到u^* _d；将u^* _d与高频电压U_hcosω_ht相加获得u^* _d+U_hcosω_ht,对u^* _d+U_hcosωt和u^* _q进行dq/abcdef变换，得到对应逆变器六相桥臂的占空比。The position ^sensorless control method of the six-phase permanent magnet motor based on pulse high frequency injection used in the prior art is shown in FIG3 , and its speed control method is shown in FIG2 .

The difference

Input it into the first PI link to obtain the given q-axis current i _q ^* of the motor, obtain the six-phase currents _ia , _ib , _ic , _id , _ie and _if of the motor through the current sensor, perform abcdef/dq transformation on _ia , _ib , _ic , _id , _ie and _if to obtain the actual q-axis current i _q and d-axis current _id ; input the difference i _q ^* -i _q between the given q-axis current i _q ^* and the actual q-axis current i _q to the second PI link to obtain u ^* _q ; set the given d-axis current i ^* _d , input the difference i ^* _d -i _d between the given d-axis current i ^* _d and _the actual d-axis current id to the second PI link to obtain u ^* _d ; add u ^* _d to the high-frequency voltage _Uh cosω _h t to obtain u ^* _d + _Uh cosω _h t, perform abcdef/dq transformation on u ^* _d + _Uh cosωt and u ^* _q is transformed into dq/abcdef to obtain the duty cycle of the six-phase bridge arm of the corresponding inverter.

The core idea of the above technical solution is: inject a high-voltage signal U _h cos ω _h t on the estimated d-axis, and obtain the generated zero-sequence voltage as follows:

轴与电机的实际d轴夹角为

电机的实际d轴与α轴的夹角为θ，则

U_hcosω_ht产生的dq轴电流的变化率为：remember

The actual d-axis angle between the shaft and the motor is

The angle between the actual d-axis and α-axis of the motor is θ, then

The rate of change of the dq-axis current generated by U _h cos ω _h t is:

The six-phase current conversion rates generated by U _h cos ω _h t are calculated separately as follows:

The six-phase voltages generated by U _h cos ω _h t are calculated separately as follows:

The zero-sequence voltage generated by U _h cos ω _h t is as follows:

作如下变换：In the above formula,

Make the following transformations:

经过低通滤波器滤波可得：Will

After filtering with a low-pass filter, we get:

Where k is the filter coefficient.

The above filtering results are transformed into products and differences to obtain:

依次通过PI调节器和积分环节得到电机转子的辨识位置。Will

The identified position of the motor rotor is obtained through the PI regulator and the integral link in sequence.

会伴随着

一同进入PI调节器，稳态运行时，

那么，

所以在辨识的转子位置中会有一个六倍频的干扰信号(该干扰信号的频率为电机转角频率的六倍)，如图4所示。可以看出，传统的基于脉振高频注入的无位置传感器控制方法六次谐波的含量较高。From the above traditional methods, it can be seen that the core idea of the traditional position-free method based on pulse high-frequency injection is to inject a high-frequency signal on the estimated d-axis. The signal is a pulse signal on the estimated d-axis, and its corresponding integrated vector is not a rotation amount. In this injection method,

Will be accompanied by

Enter the PI regulator together, and when running in steady state,

So,

Therefore, there will be a six-fold interference signal in the identified rotor position (the frequency of the interference signal is six times the motor angular frequency), as shown in Figure 4. It can be seen that the traditional position sensorless control method based on pulse high-frequency injection has a high content of sixth harmonics.

2. Position estimation method of permanent magnet motor based on pulse high frequency injection of rotating comprehensive vector.

The following is an analysis of the motor rotor position estimation method proposed in the existing patent "A method for estimating the position of a permanent magnet motor based on pulse high-frequency injection of a rotating integrated vector, application number 2021106754854". The control block diagram of the above method is shown in Figure 5, and its speed control method also adopts the control method shown in Figure 2.

的差值

输入至第一PI环节，获得电机的给定q轴电流i_q ^*，通过电流传感器获取电机的六相电流i_a，i_b，i_c，i_d，i_e和i_f，对i_a，i_b，i_c，i_d，i_e和i_f进行abcdef/dq变换，获得实际q轴电流i_q和d轴电流i_d；将给定q轴电流i_q ^*和实际q轴电流i_q的差值i_q ^*-i_q输入至第二PI环节，得到u^* _q；设定给定d轴电流i^* _d，将给定d轴电流i^* _d和实际d轴电流i_d的差值i^* _d-i_d输入至第二PI环节，得到u^* _d；将u^* _d与高频电压U_hcosω_ht相加获得u^* _d+U_hcosω_ht,将u^* _q与高频电压U_hsinω_ht相加获得u^* _q+U_hsinω_ht,对u^* _d+U_hcosωt和u^* _q+U_hsinω_ht进行dq/abcdef变换，得到对应逆变器六相桥臂的占空比。The given motor electrical angular frequency ω ^* and the estimated electrical angular frequency

The difference

Input it into the first PI link to obtain the given q-axis current i _q ^* of the motor, obtain the six-phase currents _ia , _ib , _ic , _id , _ie and _if of the motor through the current sensor, perform abcdef/dq transformation on _ia , _ib , _ic , _id , _ie and _if to obtain the actual q-axis current i _q and d-axis current _id ; input the difference i _q ^* -i _q between the given q-axis current i _q ^* and the actual q-axis current i _q to the second PI link to obtain u ^* _q ; set the given d-axis current i ^* _d , input the difference i ^* _d -i _d between the given d-axis current i ^* _d and _the actual d-axis current id to the second PI link to obtain u ^* _d ; add u ^* _d to the high-frequency voltage _Uh cosω _h t to obtain u ^* _d + _Uh cosω _h t, add u ^* _q to the high-frequency voltage _Uh sinω _h t are added to obtain u ^* _q +U _h sinω _h t, and u ^* _d +U _h cosωt and u ^* _q +U _h sinω _h t are transformed by dq/abcdef to obtain the duty cycle of the corresponding six-phase bridge arm of the inverter.

来估计电机转子位置，产生的零序电压求取过程如下：The core idea of this method is to inject a high-frequency voltage signal of the rotating integrated vector into the estimated coordinate system.

To estimate the motor rotor position, the generated zero-sequence voltage is obtained as follows:

轴与电机的实际d轴夹角为

电机的实际d轴与α轴的夹角为θ，则

产生的dq轴电流的变化率为：remember

The actual d-axis angle between the shaft and the motor is

The angle between the actual d-axis and α-axis of the motor is θ, then

The resulting rate of change of the dq axis current is:

产生的六相电流变换率为：Calculate separately

The resulting six-phase current conversion rate is:

产生的六相电压为：Calculate separately

The six-phase voltage generated is:

产生的零序电压如下：calculate

The resulting zero-sequence voltage is as follows:

作如下变换：right

Make the following transformations:

经过低通滤波器滤波可得Will

After filtering with a low-pass filter, we can get

依次通过PI调节器和积分环节得到电机转子的辨识位置。Where k is the filter coefficient.

The identified position of the motor rotor is obtained through the PI regulator and the integral link in sequence.

没有六倍频的干扰，具体如图6所示。与图4的现有技术相比，转子估计误差大大减少，因此与图3中的传统方法相比，基于旋转综合矢量的脉振高频注入的无位置方法提高了转子辨识精度。但是，在该算法中，在估计参考坐标系注入

的高频电压信号，会在电机q轴产生如下电流：From the above process, it can be seen that the algorithm provided by the patent finally enters the PI regulator only

There is no interference from the sixth frequency, as shown in Figure 6. Compared with the prior art of Figure 4, the rotor estimation error is greatly reduced. Therefore, compared with the traditional method in Figure 3, the position-free method based on the pulse high-frequency injection of the rotating integrated vector improves the rotor identification accuracy. However, in this algorithm, the injection of the estimated reference coordinate system

The high-frequency voltage signal will generate the following current on the motor q axis:

The torque ripple produced by this current is as follows:

Among them, P _r is the number of rotor poles of the motor, and ψ _fm is the permanent magnet flux of the motor.

的转矩脉动。如图7所示，转矩脉动峰峰值达到0.2N.m。It can be seen that the current has a frequency of ω _h and an amplitude of

As shown in Figure 7, the peak-to-peak value of the torque pulsation reaches 0.2Nm.

3. The present invention is a position sensorless control method based on high frequency injection of double winding pulses.

The speed control framework of the position sensorless control method provided by the present invention is shown in FIG8 , and the speed control method of the six-phase permanent magnet motor adopted is shown in FIG1 .

The six-phase permanent magnet motor winding is divided into two sets of independent windings, wherein A, B, C are the first set of windings, and X, Y, Z are the second set of windings;

的差值

输入至第一PI环节，获得电机的给定q轴电流i_q ^*；将给定q轴电流i_q ^*和实际q轴电流i_{q_set1}的差值i_q ^*-i_{q_set1}输入至第二PI环节，得到u^* _{q_set1}；设定给定d轴电流i^* _{d_set1}，将给定d轴电流i^* _{d_set1}和实际d轴电流i_{d_set1}的差值i^* _{d_set1}-i_{d_set1}输入至第二PI环节，得到u^* _{d_set1}；对u^* _{d_set1}注入高频电压U_hcosω_ht获得u^* _{d_set1}+U_hcosω_ht，对u^* _{d_set1}+U_hcosωt和u^* _{q_set1}进行dq/abc变换，得到对应逆变器A，B，C相桥臂的占空比；The three-phase currents i _a , i _b , i _c of the first set of windings of the motor are obtained by current sensors, and abc/dq transformation is performed on i _a , i _b , i _c to obtain the actual q-axis current i _{q_set1} and d-axis current i _{d_set1} of the first set of windings; the given motor electrical angular frequency ω ^* is compared with the estimated electrical angular frequency

The difference

Input into the first PI link to obtain the given q-axis current i _q ^* of the motor; input the difference i _q ^* -i _{q_set1} between the given q-axis current i _q ^* and the actual q-axis current i _{q_set1} into the second PI link to obtain u ^* _{q_set1} ; set the given d-axis current i ^* _{d_set1} , and input the difference i ^* _{d_set1} -i _{d_set1} between the given d-axis current i ^* _{d_set1} and the actual d-axis current i _{d_set1} into the second PI link to obtain u ^* _{d_set1} ; inject high-frequency voltage U _h cosω _h t into u ^* _{d_set1} to obtain u ^* _{d_set1} +U _h cosω _h t, perform dq/abc transformation on u ^* _{d_set1} +U _h cosωt and u ^* _{q_set1} to obtain the duty cycle of the corresponding inverter A, B, and C phase bridge arms;

Similarly, the three-phase currents i _x , i _y , i _z of the second set of windings of the motor are obtained through the current sensor, and abc/dq transformation is performed on i _x , i _y , i _z to obtain the actual q-axis current i _{q_set2} and d-axis current i _{d_set2} of the second set of windings; the difference i _q ^* -i _{q_set2} between the given q-axis current i _q ^* and the actual q-axis current i _{q_set2} is input to the second PI link to obtain u ^* _{q_set2} ; the given d-axis current i ^* _{d_set2} is set, and the difference i ^* _{d_set2} -i _{d_set2} between the given d-axis current i ^* _{d_set2} and the actual d- ^axis current i _{d_set2} is input _to the second PI link to obtain u ^* _{d_set2} ; the high-frequency voltage U _{h sinω h} t is injected into u ^* _{q_set2} to obtain u ^* _{q_set2} +U _h sinω _{h t} ; t and u ^* _{d_set2} are transformed into dq/abc to obtain the duty cycle of the corresponding inverter X, Y, and Z phase bridge arms.

Two independent high-frequency signals are introduced and injected into the estimated reference coordinate systems of the first set of windings and the second set of windings of the six-phase motor respectively to estimate the motor rotor position. The specific steps are as follows:

注入电机第一套绕组的估计参考坐标系，将

注入电机第二套绕组的估计参考坐标系，并分别求解各相电压，其中U_h为注入高频信号的幅值，ω_h为注入高频信号的频率，Step S1: For the first set of windings,

Inject the estimated reference frame of the first set of motor windings into

The estimated reference coordinate system of the second set of motor windings is injected, and the voltage of each phase is solved respectively, where _Uh is the amplitude of the injected high-frequency signal, _ωh is the frequency of the injected high-frequency signal,

产生的dq轴电流的变化率为：Step L1.1: The first set of windings is injected

The resulting rate of change of the dq axis current is:

产生的三相电流变换率如下：Step L1.2: Calculate

The resulting three-phase current conversion rate is as follows:

产生的三相电压如下：Step L1.3: Calculate

The three-phase voltages generated are as follows:

后各相电压求解如下：For the second winding, the injected voltage signal

The voltage of each phase is then solved as follows:

后产生的dq轴电流的变化率为：Step M1.1: The second set of windings is injected

The change rate of the dq axis current generated is:

产生的三相电流变换率如下：Step M1.2: Calculate

The resulting three-phase current conversion rate is as follows:

产生的三相电压如下：Step M1.3: Calculate

The three-phase voltages generated are as follows:

Step S2: According to the above-obtained phase voltages, the zero-sequence voltage is obtained as follows:

Step S3, transform the zero-sequence voltage as follows:

The transformation result is input into a low-pass filter for filtering to obtain:

Where k is the filter coefficient;

Step S4, inputting the low-pass filtering result into the PI adjustment link to obtain the estimated electrical angular frequency of the motor, and inputting the estimated electrical angular frequency into the integration link to obtain the estimated position of the motor rotor.

没有六倍频的干扰，如图9所示，因此与图3中的传统方法相比，本发明提出的方案可以有效提高转子辨识精度。It can be seen that for the algorithm of the present invention, only

There is no interference of the sixth frequency, as shown in FIG9 , so compared with the traditional method in FIG3 , the solution proposed in the present invention can effectively improve the rotor identification accuracy.

At the same time, in the solution proposed by the present invention, two independent high-frequency signals are injected into two independent sets of windings for position sensorless control. The injected high-frequency signal will only generate a high-frequency current in the q-axis of the second set of windings. The current generated by the high-frequency signal on the q-axis is as follows:

The torque ripple produced by this current is as follows:

的转矩脉动，相对于基于旋转综合矢量的脉振高频注入的无位置方法，本发明产生的转矩脉动减小了一半，转矩脉动峰峰值为0.1N.m，如图10所示。It can be seen that this current will generate a frequency of ω _h and an amplitude of

The torque pulsation produced by the present invention is reduced by half compared with the position-free method based on the pulse high-frequency injection of the rotating integrated vector, and the peak-to-peak value of the torque pulsation is 0.1Nm, as shown in FIG10 .

的转矩脉动，体现为图7，而本发明产生的转矩脉动幅值为

减小为现有专利的一半，体现为图10。At the same time, it is obvious that the solutions proposed by the existing patent and the present invention both solve the problem of interference with the sixth frequency. However, the signal injected by the patent introduces an amplitude of

The torque pulsation is shown in Figure 7, while the torque pulsation amplitude generated by the present invention is

It is reduced to half of the existing patent, as shown in Figure 10.

The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims (2)

1. A position sensorless control method for double winding pulse high frequency injection of a six-phase permanent magnet motor, wherein the six-phase permanent magnet motor winding is divided into two independent windings, wherein A, B, and C are the first winding, and X, Y, and Z are the second winding; The three-phase currents i _a , i _b , i _c of the first set of windings of the motor are obtained by current sensors, and abc/dq transformation is performed on i _a , i _b , i _c to obtain the actual q-axis current i _{q_set1} and d-axis current i _{d_set1} of the first set of windings; the given motor electrical angular frequency ω ^* is compared with the estimated electrical angular frequency

The difference

Input into the first PI link to obtain the given q-axis current i _q ^* of the motor; input the difference i _q ^* -i _{q_set1} between the given q-axis current i _q ^* and the actual q-axis current i _{q_set1} into the second PI link to obtain u ^* _{q_set1} ; set the given d-axis current i ^* _{d_set1} , and input the difference i ^* _{d_set1} -i _{d_set1} between the given d-axis current i ^* _{d_set1} and the actual d-axis current i _{d_set1} into the second PI link to obtain u ^* _{d_set1} ; inject high-frequency voltage U _h cosω _h t into u ^* _{d_set1} to obtain u ^* _{d_set1} +U _h cosω _h t, perform dq/abc transformation on u ^* _{d_set1} +U _h cosωt and u ^* _{q_set1} to obtain the duty cycle of the corresponding inverter A, B, and C phase bridge arms; Similarly, the three-phase currents i _x , i _y , i _z of the second set of windings of the motor are obtained through the current sensor, and abc/dq transformation is performed on i _x , i _y , i _z to obtain the actual q-axis current i _{q_set2} and d-axis current i _{d_set2} of the second set of windings; the difference i _q ^* -i _{q_set2} between the given q-axis current i _q ^* and the actual q-axis current i _{q_set2} is input to the second PI link to obtain u ^* _{q_set2} ; the given d-axis current i ^* _{d_set2} is set, and the difference i ^* _{d_set2} -i _{d_set2} between the given d-axis current i ^* _{d_set2} and the actual d- ^axis current i _{d_set2} is input _to the second PI link to obtain u ^* _{d_set2} ; the high-frequency voltage U _{h sinω h} t is injected into u ^* _{q_set2} to obtain u ^* _{q_set2} +U _h sinω _{h t} ; t and u ^* _{d_set2} are transformed by dq/abc to obtain the duty cycle of the corresponding inverter X, Y, and Z phase bridge arms; it is characterized in that two independent high-frequency signals are introduced and injected into the estimated reference coordinate system of the first set of windings and the second set of windings of the six-phase motor respectively to estimate the motor rotor position, and the specific steps are as follows: Step S1: For the first set of windings,

Inject the estimated reference frame of the first set of motor windings into

The estimated reference coordinate system of the second set of motor windings is injected, and the phase voltages are solved as follows: U _h is the amplitude of the injected high-frequency signal, and ω _h is the frequency of the injected high-frequency signal;

Where _L0 is the average value of the motor's self-inductance, _M0 is the average value of the motor's mutual inductance, _Ld is the motor's d-axis inductance, _Lq is the motor's q-axis inductance,

in

is the difference between the actual d-axis position and the estimated d-axis position; Step S2: According to the above-obtained phase voltages, the zero-sequence voltage is obtained as follows:

Step S3, transform the zero-sequence voltage as follows:

The transformation result is input into a low-pass filter for filtering to obtain:

Where k is the filter coefficient; Step S4, inputting the low-pass filtering result into the PI adjustment link to obtain the estimated electrical angular frequency of the motor, and inputting the estimated electrical angular frequency into the integration link to obtain the estimated position of the motor rotor. 2. A position sensorless control method for double winding pulse high frequency injection for a six-phase permanent magnet motor according to claim 1, characterized in that in step S1, the first winding is injected with a voltage signal

The voltage of each phase is then solved as follows: Step L1.1: The first set of windings is injected

The resulting rate of change of the dq axis current is:

Step L1.2: Calculate

The resulting three-phase current conversion rate is as follows:

Step L1.3: Calculate

The three-phase voltages generated are as follows:

For the second winding, the injected voltage signal

The voltage of each phase is then solved as follows: Step M1.1: The second set of windings is injected

The change rate of the dq axis current generated is:

Step M1.2: Calculate

The resulting three-phase current conversion rate is as follows:

Step M1.3: Calculate

The three-phase voltages generated are as follows:

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