阅读说明：本技术 永磁同步电机的控制系统、控制方法及无人飞行器 (Control system and control method of permanent magnet synchronous motor and unmanned aerial vehicle ) 是由 陈毅东 于 2016-11-18 设计创作，主要内容包括：本发明公开了一种永磁同步电机的控制系统,包括坐标变换单元、控制单元、信号处理单元和逆变器；坐标变换单元用于将三相定子电流I<Sub>a</Sub>、I<Sub>b</Sub>和I<Sub>c</Sub>转换成d-q同步旋转坐标系下的实际定子电流I<Sub>d</Sub>和I<Sub>q</Sub>；控制单元用于将给定定子电流I<Sub>dref</Sub>和实际定子电流I<Sub>d</Sub>计算输出给定d轴电压U<Sub>dref</Sub>,所述给定定子电流I<Sub>dref</Sub>＝0；信号处理单元用于将给定d轴电压U<Sub>dref</Sub>和给定q轴电压U<Sub>qref</Sub>处理调制成控制信号；逆变器用于将控制信号调制定子三相对绕组的实际电流,并驱动所述永磁同步电机运行。本发明的永磁同步电机的控制系统仅包括一个电流环,减小了控制系统中的参数计算和调节,从而提高了永磁同步电机的控制系统的动态响应速度。(The invention discloses a control system of a permanent magnet synchronous motor, which comprises a coordinate transformation unit, a control unit, a signal processing unit and an inverter, wherein the coordinate transformation unit is used for transforming a coordinate of the permanent magnet synchronous motor into a coordinate; the coordinate transformation unit is used for transforming the three-phase stator current I a 、I b And I c Converting the actual stator current I into the actual stator current I under the d-q synchronous rotating coordinate system d And I q (ii) a The control unit is used for giving a given stator current I dref And the actual stator current I d Calculating and outputting given d-axis voltage U dref Said given stator current I dref 0; the signal processing unit is used for giving a given d-axis voltage U dref And a given q-axis voltage U qref Processing and modulating the signal into a control signal; and the inverter is used for modulating the actual current of three opposite windings of the stator by the control signal and driving the permanent magnet synchronous motor to operate. Book (I)The control system of the permanent magnet synchronous motor only comprises one current loop, so that parameter calculation and adjustment in the control system are reduced, and the dynamic response speed of the control system of the permanent magnet synchronous motor is improved.)

1. The control system of the permanent magnet synchronous motor is characterized by comprising a coordinate transformation unit, a control unit, a signal processing unit and an inverter;

the coordinate transformation unit is used for transforming three-phase stator current I_a、I_bAnd I_cConverting the actual stator current I into the actual stator current I under the d-q synchronous rotating coordinate system_dAnd I_q；

The control unit is used for giving a given stator current I_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_drefSaid given stator current I_dref＝0；

The signal processing unit is used for converting the given d-axis voltage U_drefAnd a given q-axis voltage U_qrefProcessing and modulating the signal into a control signal;

the inverter is used for modulating the actual current of the stator three-phase symmetrical winding by the control signal and driving the permanent magnet synchronous motor to operate.

2. The control system of a permanent magnet synchronous motor according to claim 1, wherein the control unit includes a subtractor and a current loop integral separation PI regulator; the subtracter is used for calculating the given stator current I_drefAnd the actual stator current I_dA difference of (d); the current loop integral separation PI regulator is used for carrying out proportional and integral calculation on the difference value to obtain the given d-axis voltage U_dref。

3. Control system of a permanent magnet synchronous machine according to claim 1, characterized in that the given q-axis voltage U_qrefWith a given rotational speed ω of the permanent magnet synchronous motor_refAre equal in size.

4. Control system of a permanent magnet synchronous machine according to claim 1 or 2, characterized in that the signal processing unit comprises ParkAn inverse transform unit and a space vector modulator; the Park inverse transformation unit is used for converting the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefConverting the voltage component into a voltage component U under an alpha beta two-phase static coordinate system_αAnd U_β(ii) a The space vector modulator is used for modulating the voltage component U_αAnd U_βAnd calculating and processing to output a pulse width control signal.

5. The control system of a permanent magnet synchronous motor according to claim 1 or 2, wherein the coordinate transformation unit includes a Clarke transformation unit and a Park transformation unit; the Clarke conversion unit is used for converting three-phase stator current I_a、I_bAnd I_cConverting the stator current I into the stator current I under an alpha-beta two-phase static coordinate system_αAnd I_β(ii) a The Park conversion unit is used for converting the stator current I_αAnd I_βConverting the current into stator current I under a d-q synchronous rotating coordinate system_dAnd I_q。

6. An unmanned aerial vehicle comprising a fuselage and a permanent magnet synchronous motor mounted on the fuselage, characterized in that the permanent magnet synchronous motor comprises a control system for a permanent magnet synchronous motor according to any one of claims 1 to 5.

7. A control method of a permanent magnet synchronous motor, characterized by comprising:

three-phase stator current I_a、I_bAnd I_cConverting the actual stator current I into the actual stator current I under the d-q synchronous rotating coordinate system_dAnd I_q；

Inputting given stator current I_drefAnd according to said given stator current I_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_drefSaid given stator current I_dref＝0；

Inputting given q-axis voltage U_qrefAnd according to the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefTreatment ofModulating the signal into a control signal;

and modulating the actual current of the stator three-phase symmetrical winding of the permanent magnet synchronous motor by the control signal to drive the permanent magnet synchronous motor to operate.

8. The control method of a permanent magnet synchronous motor according to claim 7, characterized in that the given q-axis voltage U_qrefWith a given rotational speed ω of the permanent magnet synchronous motor_refAre equal in size.

9. The method according to claim 7 or 8, further comprising per-unit-designing a control system of the permanent magnet synchronous motor.

10. Method for controlling a permanent magnet synchronous machine according to any of claims 7-9, characterized in that the given stator current I is preceded by_drefAnd the actual stator current I_dCalculating a difference value, and performing proportional and integral calculation on the difference value to obtain the given d-axis voltage U_dref。

11. Method for controlling a permanent-magnet synchronous machine according to any of claims 7-10, characterized in that the given stator current I_drefAnd said given q-axis voltage U_qrefAnd outputting the data through a digital information processing system.

Technical Field

The invention relates to the technical field of permanent magnet synchronous motor control, in particular to a control system and a control method of a permanent magnet synchronous motor and an unmanned aerial vehicle.

Background

The permanent magnet synchronous motor has the advantages of high power density, small volume, no need of excitation, high power factor, high position control precision and the like, and is more and more widely applied to a high-performance control system.

The control system of the existing permanent magnet synchronous motor comprises an outer ring speed ring and an inner ring current ring, wherein the outer ring speed ring generates a given value of stator current, and the inner ring current ring obtains an actual control signal, so that the existing permanent magnet synchronous motor control system forms a double closed-loop system.

However, in the implementation process of the embodiment of the present invention, the inventor finds that in the implementation process of the existing permanent magnet synchronous motor control system, because parameters in the outer ring speed ring and the inner ring current ring are too many, a large amount of parameter calculation and adjustment are required, thereby reducing the dynamic response speed of the control system.

Disclosure of Invention

The technical problem mainly solved by the embodiment of the invention is to provide a permanent magnet synchronous motor control system, a control method and an unmanned aerial vehicle, which can improve the dynamic response speed of the permanent magnet synchronous motor control system.

In order to solve the above technical problem, one technical solution adopted by the embodiment of the present invention is: the control system of the permanent magnet synchronous motor comprises a coordinate transformation unit, a control unit, a signal processing unit and an inverter;

the coordinate transformation unit is used for transforming three-phase stator current I_a、I_bAnd I_cConverting the actual stator current I into the actual stator current I under the d-q synchronous rotating coordinate system_dAnd I_q；

The control unitFor applying a given stator current I_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_drefSaid given stator current I_dref＝0；

The signal processing unit is used for converting the given d-axis voltage U_drefAnd a given q-axis voltage U_qrefProcessing and modulating the signal into a control signal;

the inverter is used for modulating the actual current of the three opposite windings of the stator by the control signal and driving the permanent magnet synchronous motor to operate.

In some embodiments, the given q-axis voltage U_qrefWith a given rotational speed ω of the permanent magnet synchronous motor_refAre equal in size.

In some of these embodiments, the control unit comprises a subtractor and a current loop integrate-separate PI regulator; the subtracter is used for calculating the given stator current I_drefAnd the actual stator current I_dA difference of (d); the current loop integral separation PI regulator is used for carrying out proportional and integral calculation on the difference value to obtain the given d-axis voltage U_dref。

In some of these embodiments, the signal processing unit comprises an inverse Park transform unit and a spatial vector modulator; the Park inverse transformation unit is used for converting the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefConverting the voltage component into a voltage component U under an alpha beta two-phase static coordinate system_αAnd U_β(ii) a The space vector modulator is used for modulating the voltage component U_αAnd U_βAnd calculating and processing to output a pulse width control signal.

In some of these embodiments, the coordinate transformation unit comprises a Clarke transformation unit and a Park transformation unit; the Clarke conversion unit is used for converting three-phase stator current I_a、I_bAnd I_cConverting the stator current I into the stator current I under an alpha-beta two-phase static coordinate system_αAnd I_β(ii) a The Park conversion unit is used for converting the stator current I_αAnd I_βConverting the current into stator current I under a d-q synchronous rotating coordinate system_dAnd I_q。

The invention also provides an unmanned aerial vehicle which comprises a vehicle body and the permanent magnet synchronous motor arranged on the vehicle body, wherein the permanent magnet synchronous motor comprises the control system of any one permanent magnet synchronous motor.

The invention also provides a control method of the permanent magnet synchronous motor, which comprises the following steps:

three-phase stator current I_a、I_bAnd I_cConverting the actual stator current I into the actual stator current I under the d-q synchronous rotating coordinate system_dAnd I_q；

Inputting given stator current I_drefAnd according to said given stator current I_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_drefSaid given stator current I_dref＝0；

Inputting given q-axis voltage U_qrefAnd according to the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefProcessing and modulating the signal into a control signal;

and modulating the actual current of the stator three-phase symmetrical winding of the permanent magnet synchronous motor by the control signal to drive the permanent magnet synchronous motor to operate.

In some embodiments, the given q-axis voltage U_qrefWith a given rotational speed ω of the permanent magnet synchronous motor_refAre equal in size.

In some embodiments, the control method further includes making a control system of the permanent magnet synchronous motor per unit.

In some embodiments, the pm synchronous motor control system performs per unit processing with reference values of a rated voltage and a rated current of the pm synchronous motor as the reference values, and the given q-axis voltage U is_qrefIs equal to the given rotation speed omega of the permanent magnet synchronous motor_refAre equal in size.

In some of these embodiments, the given stator current I is first_drefAnd the actual stator current I_dCalculating difference, and then carrying out proportional and integral calculation on the difference,obtaining the given d-axis voltage U_dref。

In some of these embodiments, the given stator current I_drefAnd said given q-axis voltage U_qrefAnd outputting the data through a digital information processing system.

The beneficial effects of the embodiment of the invention are as follows: the control unit of the control system of the permanent magnet synchronous motor only comprises one current loop, so that the parameter calculation and adjustment in the control system of the permanent magnet synchronous motor are reduced, and the dynamic response speed of the control system of the permanent magnet synchronous motor is improved.

Drawings

Fig. 1 is a block diagram of a vector control system of a permanent magnet synchronous motor according to an embodiment of the present invention.

Fig. 2 is a flowchart of a method for controlling a permanent magnet synchronous motor according to an embodiment of the present invention.

Fig. 3 is a graph showing the result of an experiment using the vector control system of the permanent magnet synchronous motor shown in fig. 1.

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 will be understood that when an element is referred to as being "electrically connected" to another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "electrically connected" to another element, it can be connected by contact, e.g., by wires, or by contactless connection, e.g., by contactless coupling.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Some embodiments of the invention are described in detail below with reference to the accompanying drawings. The embodiments described below and the features of the embodiments can be combined with each other without conflict.

Fig. 1 shows a block diagram of a control system of a permanent magnet synchronous motor 100 according to an embodiment of the present invention, including a coordinate transformation unit 101, a control unit 103, a signal processing unit 105, and an inverter 107. The output end of the inverter 107 is connected with the input end of the permanent magnet synchronous motor 100, the input end of the coordinate transformation unit 101 is connected between the inverter 107 and the permanent magnet synchronous motor 100, the output end of the coordinate transformation unit 101 is connected with the input end of the control unit 103, the output end of the control unit 103 is connected with the input end of the signal processing unit 105, and the output end of the signal processing unit 105 is connected with the input end of the inverter 107.

Before further describing the operation of the control system of the permanent magnet synchronous motor 100, it should be noted that, in the embodiment of the present invention, the control system of the permanent magnet synchronous motor 100 has performed per unit processing so that the form expressed by a per unit value coincides with the form expressed by an actual value. In the embodiment of the present invention, it is preferable that the rated voltage and the rated current of the permanent magnet synchronous motor 100 are unified as reference values of the control system of the permanent magnet synchronous motor 100, and other physical quantities can be estimated from the two reference values. Since a person skilled in the art can understand per unit processing of the control system of the permanent magnet synchronous motor by combining with the embodiment of the present invention, detailed description is not repeated in the embodiment of the present invention.

The coordinate transformation unit 101 is used for transforming the three-phase stator current I of the permanent magnet synchronous motor 100_a、I_bAnd I_cConverting the current into stator current I under a d-q synchronous rotating coordinate system_dAnd I_q. Specifically, the coordinate transformation unit 101 includes a unit for transforming the three-phase stator currents I_a、I_bAnd I_cStator current I converted to alpha-beta two-phase static coordinate system_αAnd I_βI.e. Clark conversion unit 1011, and a method forApplying a stator current I_αAnd I_βStator current I converted to d-q synchronous rotation coordinate system_dAnd I_qI.e. Park transformation unit 1012.

The control unit 103 is used for controlling the stator current I according to the given value_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_drefI.e. the control unit 103 comprises a current loop. In the embodiment of the present invention, the control unit 103 includes a subtractor 1031 and a current loop integration/separation PI regulator 1032. Specifically, first, the upper system inputs a given stator current I_drefTo a subtractor 1031, while a coordinate transformation unit 101 outputs an actual stator current I_dTo subtractor 1031; secondly, a subtractor 1031 sets the stator current I_drefAnd the actual stator current I_dObtaining a difference value; then, the subtractor 1031 outputs the difference to the current loop integration and separation PI regulator 1032, and the current loop integration and separation PI regulator 1032 performs proportional and integral calculation on the difference to obtain the given d-axis voltage U_dref. In the embodiment of the invention, the stator current I is given_dref0. The term "upper system" in the present invention refers to other systems, such as a digital information processing system, which are communicatively connected to the control system of the permanent magnet synchronous motor 100.

The signal processing unit 105 is used for outputting the given d-axis voltage U according to the control unit 103_drefAnd a given q-axis voltage U output by the upper system_qrefProcessing is modulated into a control signal. In the embodiment of the present invention, the signal processing unit 105 includes a Park inverse transform unit 1051 and a space vector modulator 1052. Specifically, first, the Park inverse transformation unit 1051 transforms the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefConverting the voltage component into a voltage component U under an alpha beta two-phase static upper coordinate system_αAnd U_β(ii) a Next, the Park inverse transformation unit 1051 transforms the voltage component U_αAnd U_βOutput to space vector modulator 1052, which space vector modulator 1052 couples the voltage component U to_αAnd U_βAnd calculating and processing to output a pulse width control signal. It is to be understood that the signal processing unit 105 may also comprise onlySpace vector modulator 1052, i.e. the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefDirectly input to the space vector modulator 1052, and the space vector modulator 1052 performs calculation processing to output a pulse width control signal. In the embodiment of the invention, the given q-axis voltage U output by the upper system_qrefIs equal to the given rotation speed omega of the permanent magnet synchronous motor 100_refAre equal in size.

The inverter 107 is configured to obtain an actual current for controlling the three-phase symmetric winding of the stator according to the control signal output by the signal processing unit 105, and drive the permanent magnet synchronous motor 100 to operate.

In the present invention, the control unit 103 of the control system of the permanent magnet synchronous machine 100 comprises only one current I according to a given stator current_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_drefAccording to a given q-axis voltage U output by an upper system_qrefThe signal processing unit 105 can obtain the control signal, and further drive the permanent magnet synchronous motor 100 to operate through the inverter 107. Since the control unit 103 includes only one current loop, the parameter calculation and adjustment in the control system of the permanent magnet synchronous motor 100 are reduced, thereby improving the dynamic response speed of the control system of the permanent magnet synchronous motor 100.

The embodiment of the invention also provides the unmanned aerial vehicle, which comprises a fuselage and the permanent magnet synchronous motor 100 arranged on the fuselage, wherein the permanent magnet synchronous motor 100 is used for providing power for the unmanned aerial vehicle. The permanent magnet synchronous motor 100 on the unmanned aerial vehicle comprises the control system of the permanent magnet synchronous motor 100, and the control system only comprises one current loop, so that the parameter calculation and adjustment in the control system of the permanent magnet synchronous motor 100 are reduced, the dynamic response speed of the control system of the permanent magnet synchronous motor 100 is improved, and the rapid response speed of the unmanned aerial vehicle is improved.

Referring to fig. 2, an embodiment of the present invention further provides a control method of a control system using the permanent magnet synchronous motor 100, including the following steps:

s1, the control system of the permanent magnet synchronous motor 100 is unified per unit.

In the embodiment of the present invention, the rated voltage and the rated current of the permanent magnet synchronous motor 100 are preferably unified as reference values of the control system of the permanent magnet synchronous motor 100.

S2, converting the three-phase stator current I_a、I_bAnd I_cConverting the actual stator current I into the actual stator current I under the d-q synchronous rotating coordinate system_dAnd I_q。

In the embodiment of the invention, the three-phase stator current I is firstly_a、I_bAnd I_cStator current I converted into alpha beta two-phase static upper coordinate system through Clark conversion_αAnd I_βThen the stator current I is converted by Park_αAnd I_βActual stator current I converted into d-q synchronous rotating coordinate system_dAnd I_q。

S3, inputting a given stator current I_drefAnd according to said given stator current I_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_dref。

In the embodiment of the invention, the stator current I is given first_drefAnd the actual stator current I_dCalculating a difference value through a subtracter 1031, and performing proportional and integral calculation on the difference value through a current loop integral separation PI regulator 1032 to obtain the given d-axis voltage U_dref。

S4, inputting a given q-axis voltage U_qrefAnd according to the given d-axis voltage U_drefAnd said given q-axis voltage U_qrefProcessing is modulated into a control signal.

In the embodiment of the invention, the given d-axis voltage U is firstly given_drefAnd said given q-axis voltage U_qrefConverted into a voltage component U under an alpha beta two-phase static upper coordinate system by a Park inverse conversion unit 1051 of the signal processing unit 105_αAnd U_β(ii) a The voltage component U is then passed through a space vector modulator 1052_αAnd U_βAnd calculating and processing to output a pulse width control signal. In the embodiment of the invention, the given q-axis voltage U output by the upper system_qrefIs equal to the given rotation speed omega of the permanent magnet synchronous motor 100_refAre equal in size.

And S5, modulating the actual current of the stator three-phase symmetrical winding of the permanent magnet synchronous motor 100 by the control signal, and driving the permanent magnet synchronous motor 100 to operate.

It is to be understood that step S1 in the above control method may be eliminated, and that when S1 is eliminated, the q-axis voltage U is given in step S4_qrefThe value of (c) can be set according to the control requirements.

In the control method of the permanent magnet synchronous motor 100 of the present invention, only the given stator current I needs to be input_drefAnd according to said given stator current I_drefAnd the actual stator current I_dCalculating and outputting given d-axis voltage U_dref(ii) a Then according to the given d-axis voltage U_drefAnd a given q-axis voltage U_qrefThe control signal can be obtained by processing and modulating, and parameter calculation and adjustment in the control system of the permanent magnet synchronous motor 100 are reduced, so that the dynamic response speed of the control system of the permanent magnet synchronous motor 100 is improved.

Referring to fig. 3, an experimental result of a permanent magnet synchronous motor using the control system of the permanent magnet synchronous motor 100 according to the embodiment of the present invention is shown.

Fig. 3 is a waveform record of actual current of three-phase symmetrical windings of a stator and a control signal input in an inverter 107 in the speed increasing process of the permanent magnet synchronous motor, wherein the actual current waveform 200 is a smooth sine wave, and a modulation waveform 300 formed by the control signal is a saddle wave. As can be seen from fig. 3, the actual current waveform 200 and the modulation waveform 300 are very synchronous, that is, the control system of the permanent magnet synchronous motor has excellent dynamic response speed, and meets the requirement of the load with dynamic response speed, for example, the control system of the permanent magnet synchronous motor of the unmanned aerial vehicle.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes performed by the present specification and drawings, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.