CN117175992A

CN117175992A - Asynchronous motor control method and device, asynchronous motor controller and storage medium

Info

Publication number: CN117175992A
Application number: CN202210581464.0A
Authority: CN
Inventors: 金磊; 许培林; 赵小安
Original assignee: SHENZHEN SUNYE ELECTRIC CO Ltd; Midea Welling Motor Technology Shanghai Co Ltd
Current assignee: SHENZHEN SUNYE ELECTRIC CO Ltd; Midea Welling Motor Technology Shanghai Co Ltd
Priority date: 2022-05-26
Filing date: 2022-05-26
Publication date: 2023-12-05

Abstract

The application is suitable for the technical field of asynchronous motor control, and provides an asynchronous motor control method, an asynchronous motor control device, an asynchronous motor controller and a storage medium, wherein the stator resistance is identified by keeping the mutual inductance of an asynchronous motor constant, so that the stator resistance of the asynchronous motor can be accurately identified, and the convergence of the stator resistance is ensured; or, the stator resistance of the asynchronous motor is kept to be constant, mutual inductance is identified, the mutual inductance of the asynchronous motor can be accurately identified, and the convergence of the mutual inductance is ensured; therefore, the flux linkage angle and the rotating speed of the asynchronous motor can be accurately estimated, the asynchronous motor is subjected to feedback control based on the estimated values of the flux linkage angle and the rotating speed, and the control precision and the reliability are high.

Description

Asynchronous motor control method and device, asynchronous motor controller and storage medium

Technical Field

The application belongs to the technical field of asynchronous motor control, and particularly relates to an asynchronous motor control method and device, an asynchronous motor controller and a storage medium.

Background

With the development of power electronics technology and alternating current motor transmission technology, a variable speed transmission system consisting of a frequency converter and an alternating current motor is widely applied to the fields of rail transit, electric automobiles, machining, household appliances and the like. Asynchronous motors (also known as induction motors) in ac motors are widely used transmission devices in variable speed transmission systems due to their low cost, high reliability, ease of maintenance, and the like.

The control method of the asynchronous motor mostly adopts a vector control method based on flux linkage orientation, so that the asynchronous motor can obtain the performance comparable to that of a direct current speed regulation system. The key of the vector control method is that the magnetic field is accurately oriented, and the correctly oriented magnetic field must rely on the physical parameters of the asynchronous motor to complete decoupling control, so that accurately identifying the physical parameters of the asynchronous motor is a prerequisite for the vector control method to exert its advantages.

Disclosure of Invention

The embodiment of the application provides an asynchronous motor control method, an asynchronous motor control device, an asynchronous motor controller and a storage medium, which can accurately identify physical parameters of an asynchronous motor, so that the flux linkage angle and the rotating speed of the asynchronous motor can be accurately estimated, and the asynchronous motor is subjected to feedback control based on the estimated values of the flux linkage angle and the rotating speed, so that the control precision and the reliability are high.

A first aspect of an embodiment of the present application provides a method for controlling an asynchronous motor, including:

obtaining a first flux linkage of an M-th period according to the stator phase voltage of the M-th period, the stator phase current of the M-th period, the stator resistance of the M-1-th period, the first flux linkage of the M-1-th period and the second flux linkage of the M-1-th period;

Obtaining a second flux linkage of the M-th period according to the stator phase current of the M-th period, the rotating speed of the M-1-th period, the first flux linkage of the M-1-th period and the second flux linkage of the M-1-th period;

obtaining the stator resistance of the Mth period according to the error between the first flux linkage of the Mth period and the second flux linkage of the Mth period and the stator phase current of the Mth period;

obtaining a third flux linkage of the Mth period according to the first flux linkage of the Mth period and the second flux linkage of the Mth period;

according to the third flux linkage of the M period, obtaining the flux linkage angle of the M period and the stator frequency of the M period;

obtaining the slip frequency of the Mth period according to the stator phase current of the Mth period and the third flux linkage of the Mth period;

obtaining the rotating speed of the Mth period according to the stator frequency of the Mth period and the slip frequency of the Mth period;

according to the flux linkage angle of the Mth period and the rotating speed of the Mth period, feedback control is carried out on the asynchronous motor in the M+1th period;

wherein M is a positive integer.

A second aspect of the embodiment of the present application provides an asynchronous motor control method, including:

obtaining the first flux linkage of the N period according to the stator phase voltage of the N period, the stator phase current of the N period, the first flux linkage of the N-1 period and the second flux linkage of the N-1 period;

According to the stator phase current of the N-th period, the rotating speed of the N-1 th period, the mutual inductance of the N-1 th period, the first flux linkage of the N-1 th period and the second flux linkage of the N-1 th period, the second flux linkage of the N-th period is obtained;

obtaining the mutual inductance of the N-th period according to the error between the first flux linkage of the N-th period and the second flux linkage of the N-th period and the stator phase current of the N-th period;

obtaining a third flux linkage of the N period according to the first flux linkage of the N period and the second flux linkage of the N period;

according to the third flux linkage of the N-th period, obtaining the flux linkage angle of the N-th period and the stator frequency of the N-th period;

obtaining the slip frequency of the N-th period according to the stator phase current of the N-th period and the third flux linkage of the N-th period;

according to the stator frequency of the N-th period and the slip frequency of the N-th period, the rotating speed of the N-th period is obtained;

according to the flux linkage angle of the N period and the speed for rotating the N period, carrying out feedback control on the asynchronous motor in the (n+1) period;

wherein N is a positive integer.

A third aspect of the embodiment of the present application provides a control method for an asynchronous motor, including:

executing the steps of the asynchronous motor control method provided by the first aspect of the embodiment of the application in a first time period;

Executing the steps of the asynchronous motor control method provided in the second aspect of the embodiment of the application in a second time period;

or executing the steps of the asynchronous motor control method provided by the first aspect of the embodiment of the application when the stator frequency is lower than the first stator frequency threshold value;

executing the step of the asynchronous motor control method provided by the second aspect of the embodiment of the application when the stator frequency is higher than the second stator frequency threshold value;

the Mth period is in a first time period, and the Nth period is in a second time period;

the first stator frequency threshold is less than or equal to the second stator frequency threshold, the stator frequency is less than the first stator frequency threshold in the M-1 th period, and the stator frequency is greater than the second stator frequency threshold in the N-1 th period.

A fourth aspect of an embodiment of the present application provides an asynchronous motor control apparatus, including:

the first flux linkage estimation unit is used for obtaining the first flux linkage of the Mth period according to the stator phase voltage of the Mth period, the stator phase current of the Mth period, the stator resistance of the Mth period, the first flux linkage of the Mth period and the second flux linkage of the Mth period;

the second flux linkage estimation unit is used for obtaining a second flux linkage of the M-th period according to the stator phase current of the M-th period, the rotating speed of the M-1-th period, the first flux linkage of the M-1-th period and the second flux linkage of the M-1-th period;

A stator resistance estimation unit, configured to obtain a stator resistance of an mth cycle according to an error between the first flux linkage of the mth cycle and the second flux linkage of the mth cycle, and a stator phase current of the mth cycle;

a third flux linkage estimation unit, configured to obtain a third flux linkage of the mth period according to the first flux linkage of the mth period and the second flux linkage of the mth period;

the first flux linkage angle and stator frequency estimation unit is used for obtaining the flux linkage angle of the Mth period and the stator frequency of the Mth period according to the third flux linkage of the Mth period;

a first slip frequency estimation unit, configured to obtain a slip frequency of an mth period according to a stator phase current of the mth period and a third flux linkage of the mth period;

a first rotational speed estimation unit, configured to obtain a rotational speed of an mth cycle according to the stator frequency of the mth cycle and the slip frequency of the mth cycle;

the first feedback control unit is used for carrying out feedback control on the asynchronous motor in the M+1th period according to the flux linkage angle of the M period and the rotating speed of the M period;

wherein M is a positive integer.

A fifth aspect of an embodiment of the present application provides an asynchronous motor control apparatus, including:

A fourth flux linkage estimation unit, configured to obtain a first flux linkage of an nth period according to the stator phase voltage of the nth period and the stator phase current of the nth period, and the first flux linkage of the nth-1 period and the second flux linkage of the nth-1 period;

a fifth flux linkage estimation unit, configured to obtain a second flux linkage of the nth cycle according to the stator phase current of the nth cycle, the rotation speed of the nth cycle, the mutual inductance of the nth cycle, the first flux linkage of the nth cycle and the second flux linkage of the nth cycle;

the mutual inductance estimation unit is used for obtaining the mutual inductance of the N period according to the error between the first flux linkage of the N period and the second flux linkage of the N period and the stator phase current of the N period;

a sixth flux linkage estimation unit, configured to obtain a third flux linkage of the nth cycle according to the first flux linkage of the nth cycle and the second flux linkage of the nth cycle;

the second flux linkage angle and stator frequency estimation unit is used for obtaining the flux linkage angle of the N period and the stator frequency of the N period according to the third flux linkage of the N period;

the second slip frequency estimation unit is used for obtaining the slip frequency of the N period according to the stator phase current of the N period and the third flux linkage of the N period;

A second rotation speed estimation unit, configured to obtain a rotation speed of the nth cycle according to the stator frequency of the nth cycle and the slip frequency of the nth cycle;

the second feedback control unit is used for carrying out feedback control on the asynchronous motor in the (n+1) th period according to the flux linkage angle of the (N) th period and the speed for rotating the (N) th period;

wherein N is a positive integer.

A sixth aspect of the embodiments of the application provides an asynchronous motor control apparatus comprising an asynchronous motor control apparatus as claimed in claims 17 and 18;

in a first period of time, the asynchronous motor control device provided in the fourth aspect of the embodiment of the present application is applied;

in a second period of time, the asynchronous motor control device provided in the fifth aspect of the embodiment of the present application is applied;

or when the stator frequency is lower than the first stator frequency threshold value, the asynchronous motor control device provided by the fourth aspect of the embodiment of the application is applied;

when the stator frequency is higher than the second stator frequency threshold value, the asynchronous motor control device provided by the fifth aspect of the embodiment of the application is applied;

A seventh aspect of the embodiments of the present application provides an asynchronous motor controller comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of the asynchronous motor control method according to any one of the first to third aspects of the embodiments of the present application when executing the computer program.

An eighth aspect of the embodiments of the present application provides a computer-readable storage medium storing a computer program which, when executed by a processor, implements the steps of the asynchronous motor control method according to any one of the first to third aspects of the embodiments of the present application.

According to the asynchronous motor control method provided by the embodiment of the application, the mutual inductance of the asynchronous motor is kept as a constant, the stator resistance is identified, the stator resistance of the asynchronous motor can be accurately identified, the convergence of the stator resistance is ensured, the flux linkage angle and the rotating speed of the asynchronous motor can be accurately estimated, the asynchronous motor is subjected to feedback control based on the estimated value of the flux linkage angle and the rotating speed, and the control precision and the reliability are high.

According to the asynchronous motor control method provided by the second aspect of the embodiment of the application, the stator resistance of the asynchronous motor is kept constant, mutual inductance is identified, the mutual inductance of the asynchronous motor can be accurately identified, and convergence of the mutual inductance is ensured, so that the flux linkage angle and the rotating speed of the asynchronous motor can be accurately estimated, feedback control is performed on the asynchronous motor based on the estimated values of the flux linkage angle and the rotating speed, and the control precision and the reliability are high.

According to the asynchronous motor control method provided by the third aspect of the embodiment of the application, when the first time period or the time period is lower than the first stator frequency threshold value, the mutual inductance of the asynchronous motor is kept constant, the stator resistance is identified, and the stator resistance is ensured to be converged; or when the second time period or the stator frequency is higher than the second stator frequency threshold value, the stator resistance of the asynchronous motor is kept to be constant, mutual inductance is identified, and convergence of the mutual inductance is guaranteed, so that the stator resistance or the mutual inductance can be adaptively selected according to different identification conditions for identification, the flux linkage angle and the rotating speed of the asynchronous motor can be accurately estimated, feedback control is carried out on the asynchronous motor based on the estimated values of the flux linkage angle and the rotating speed, and the control precision and the reliability are high.

It is to be understood that the advantages of the fourth aspect to the sixth aspect may be referred to in the description of the first aspect to the third aspect, and the advantages of the seventh aspect and the eighth aspect may be referred to in the description of the first aspect to the third aspect, which are not repeated herein.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments or the description of the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic flow chart of a first asynchronous motor control method according to an embodiment of the present application;

fig. 2 is a schematic flow chart of a second asynchronous motor control method according to an embodiment of the present application;

fig. 3 is a schematic flow chart of a third asynchronous motor control method according to an embodiment of the present application;

fig. 4 is a schematic flow chart of a fourth asynchronous motor control method according to an embodiment of the present application;

fig. 5 is a schematic logic structure diagram of a first asynchronous motor control device according to an embodiment of the present application;

fig. 6 is a schematic logic structure diagram of a second asynchronous motor control device according to an embodiment of the present application;

fig. 7 is a schematic logic structure diagram of a first asynchronous motor control system according to an embodiment of the present application;

fig. 8 is a schematic logic structure diagram of a second asynchronous motor control system according to an embodiment of the present application;

fig. 9 is a schematic logic structure diagram of a third asynchronous motor control system according to an embodiment of the present application;

fig. 10 is a schematic logic structure diagram of a fourth asynchronous motor control system according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of an asynchronous motor controller according to an embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth such as the particular system architecture, techniques, etc., in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It should be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

It should also be understood that the term "and/or" as used in the present specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes such combinations.

As used in the present description and the appended claims, the term "if" may be interpreted as "when..once" or "in response to a determination" or "in response to detection" depending on the context. Similarly, the phrase "if a determination" or "if a [ described condition or event ] is detected" may be interpreted in the context of meaning "upon determination" or "in response to determination" or "upon detection of a [ described condition or event ]" or "in response to detection of a [ described condition or event ]".

Furthermore, the terms "first," "second," "third," and the like in the description of the present specification and in the appended claims, are used for distinguishing between descriptions and not necessarily for indicating or implying a relative importance.

Reference in the specification to "one embodiment" or "some embodiments" or the like means that a particular feature, structure, or characteristic described in connection with the embodiment is included in one or more embodiments of the application. Thus, appearances of the phrases "in one embodiment," "in some embodiments," "in other embodiments," and the like in the specification are not necessarily all referring to the same embodiment, but mean "one or more but not all embodiments" unless expressly specified otherwise. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless expressly specified otherwise.

The embodiment of the application provides four different asynchronous motor control methods, which can be executed by a processor of an asynchronous motor controller when a corresponding computer program is run, can accurately estimate the flux linkage and the rotating speed of the asynchronous motor, and can perform feedback control on the asynchronous motor according to the flux linkage angle and the rotating speed, thereby improving the reliability of controlling the asynchronous motor to rotate.

In application, the motor controller can be applied to the fields of rail transit, electric automobiles, machining, household appliances and the like, wherein the household appliances can be air conditioners, fans, washing machines, refrigerators and the like, and the motor controller can be a frequency converter.

In application, the principle of the motor controller controlling the rotation of the asynchronous motor is as follows:

the motor controller comprises a current sensor, an inverter and a processor;

the current sensor is electrically connected with the negative electrode of the direct current bus and is used for detecting bus current on the direct current bus, and the current sensor can be realized through a sampling resistor connected in series with the negative electrode of the direct current bus;

the first input end of the inverter is electrically connected with the positive electrode of the direct current bus, the second input end of the inverter is electrically connected with the negative electrode of the direct current bus, and the inverter can comprise a two-phase bridge arm or a three-phase bridge arm;

when the inverter comprises two-phase bridge arms, four controlled ends of the inverter are electrically connected with the processor, and two output ends of the inverter are respectively and electrically connected with two phase current and phase voltage input ends of the two-phase asynchronous motor;

when the inverter comprises a three-phase bridge arm, six controlled ends of the inverter are electrically connected with the processor, and three output ends of the inverter are respectively electrically connected with three phase current and phase voltage input ends of the three-phase asynchronous motor;

Each phase bridge arm of the inverter comprises two switching tubes (an upper switching tube and a lower switching tube), wherein the input ends of all the upper switching tubes are connected together to form a first input end of the inverter, the output ends of all the lower switching tubes are connected together to form a second input end of the inverter, the controlled end of each switching tube forms a controlled end of the inverter, and the output ends of the upper switching tubes and the input ends of the lower switching tubes of each phase bridge arm are connected together to form an output end of the inverter;

the processor is used for:

obtaining a stator phase voltage required to be applied to a stator according to a target rotating speed required to be achieved by the asynchronous motor so as to generate corresponding stator phase current in the stator;

a space vector pulse width modulation (Space Vector Pulse Width Modulation, SVPWM) method is adopted, a target voltage vector is determined according to the angle of a rotor and the voltage of a target phase, a comparison value is obtained through a comparison value calculation method based on the SVPWM method according to the amplitude and the phase angle of the target voltage vector, then a triangular carrier wave is adopted to compare with the comparison value obtained through calculation, a pulse width modulation (Pulse Width Modulation, PWM) signal for driving an inverter is generated, the on-off state of a switching tube of the inverter is controlled according to the PWM signal, so that the actual voltage of a bus voltage acting on a stator is equivalent to the voltage of the target phase, correspondingly, the actual current of a bus current acting on the stator is equivalent to the current of the target phase, and further the stator generates a corresponding magnetic field to drive the rotor to rotate at the target rotating speed;

In order to improve the control precision of the asynchronous motor, the current sensor is required to collect the bus current on the direct current bus to obtain the bus current on the direct current bus, so that the actual phase current applied to the stator can be estimated according to the bus current, the target phase current can be adjusted according to the deviation between the actual phase current and the target phase current by comparing the actual phase current with the target phase current, the adjusted target phase voltage can be obtained based on the adjusted target phase current, the adjusted target voltage vector can be determined by combining a space vector pulse width modulation method, an adjusted pulse width modulation signal can be generated according to the adjusted target voltage vector, the on-off state of a switching tube of the inverter is controlled according to the adjusted pulse width modulation signal, and finally the feedback control of the asynchronous motor is realized.

In application, the switch tube has the function of being turned on or off under the triggering of PWM signals, is used for playing the role of an electronic switch, and can be specifically an insulated gate bipolar transistor (Insulated Gate Bipolar Transistor, IGBT), a triode (Bipolar Junction Transistor, BJT), a field effect transistor (Field Effect Transistor, FET), a Thyristor (Thyristor) and the like, wherein the insulated gate bipolar transistor is a composite fully-controlled voltage-driven power semiconductor device consisting of a bipolar triode and an insulated gate field effect transistor, and has the advantages of high input impedance of the insulated gate field effect transistor and low conduction voltage drop of the bipolar triode, and the field effect transistor can be specifically a Metal-oxide semiconductor field effect transistor (Metal-Oxide Semiconductor FET, MOS-FET for short).

As shown in fig. 1, the first asynchronous motor control method provided by the embodiment of the present application includes steps S101 to S106 as follows:

step S101, obtaining a first flux linkage of an Mth period according to the stator phase voltage of the Mth period and the stator phase current of the Mth period, the stator resistance of the Mth period, the first flux linkage of the Mth period and the second flux linkage of the Mth period, and entering steps S103 and S104;

step S102, obtaining a second flux linkage of the M period according to the stator phase current of the M period, the rotating speed of the M-1 period, the first flux linkage of the M-1 period and the second flux linkage of the M-1 period, and entering steps S103 and S104.

In the application, M is any positive integer, and the Mth period can be any asynchronous motor control period, for example, the Mth period can be the current asynchronous motor control period, and the M-1 th period is the last asynchronous motor control period before the current asynchronous motor control period. When M is 1, the M period is the 1 st asynchronous motor control period, the M-1 th period is the 0 th asynchronous motor control period, and the 0 th asynchronous motor control period is the time when the periodic control of the asynchronous motor is not started, so that the rotating speed, the first magnetic linkage and the second magnetic linkage of the 0 th asynchronous motor control period can be 0 or preset values set according to actual needs in advance. For an asynchronous motor provided with a rotation speed sensor, the rotation speed of the 0 th asynchronous motor control period can also be detected by the rotation speed sensor.

In application, the stator phase current can be detected by a motor phase current reconstruction method based on a current sensor and a single bus current detection technology, and the stator phase voltage can be obtained by conversion calculation according to the stator phase current.

In application, the first flux linkage of the M-1 th period is obtained according to the stator phase voltage of the M-1 th period and the stator phase current of the M-1 th period, and the stator resistance of the M-2 th period, the first flux linkage of the M-2 th period and the second flux linkage of the M-2 th period, which are the same as the obtaining principle of the first flux linkage of the M-th period; similarly, the second flux linkage of the M-1 th period is obtained according to the stator phase current of the M-1 th period, the rotating speed of the M-2 th period, the first flux linkage of the M-2 th period and the second flux linkage of the M-2 th period, which are the same as the obtaining principle of the second flux linkage of the M-1 th period.

In one embodiment, step S101 includes:

the first flux linkage of the Mth period is obtained according to the stator phase voltage of the Mth period, the stator phase current of the Mth period, the rotor inductance of the Mth period, the mutual inductance of the Mth period and the total leakage inductance of the Mth period, the stator resistance of the Mth-1 period, the first flux linkage of the Mth-1 period and the second flux linkage of the Mth-1 period.

In use, the first flux linkage of the M-th cycle is obtained in particular from the stator phase voltage, stator phase current, rotor inductance, mutual inductance and total leakage inductance of the cycle, and the stator resistance of the M-1 th cycle, the first flux linkage of the M-1 th cycle and the second flux linkage of the M-1 th cycle.

In one embodiment, the calculation formula of the first flux linkage of the mth period is:

wherein p represents the derivative operator,respectively representing an alpha axis component and a beta axis component of the first flux linkage of the Mth period in a two-phase stationary coordinate system, L _r，M 、L _m，M 、L _σ，Mp Respectively representing the rotor inductance of the Mth period, the mutual inductance of the Mth period and the total leakage inductance of the Mth period, v _sα，M 、v _sβ，M Respectively representing the alpha-axis component and the beta-axis component of the stator phase voltage of the Mth period in a two-phase stationary coordinate system, < >>Stator inductance, i, representing the M-1 th period _sα，M 、i _sβ，M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the Mth period in a two-phase stationary coordinate system, +.>The first flux linkage respectively represents the alpha axis component and the beta axis component of the M-1 period under the two-phase static coordinate system, +.>The second flux linkage representing the M-1 th period respectively has an alpha-axis component and a beta-axis component in a two-phase stationary coordinate system，K ₁ Representing a first feedback matrix, k _1α 、k _1β Representing the feedback coefficients of the first feedback matrix.

In one embodiment, step S102 includes:

and obtaining the second flux linkage of the M-th period according to the stator phase current of the M-th period, the mutual inductance of the M-th period and the rotor time constant of the M-th period, the rotating speed of the M-1-th period, the first flux linkage of the M-1-th period and the second flux linkage of the M-1-th period.

In application, the second flux linkage of the M-th period is obtained according to stator phase current, mutual inductance and rotor time constant of the period, and the rotating speed of the M-1 th period, the first flux linkage of the M-1 th period and the second flux linkage of the M-1 th period.

In one embodiment, the calculation formula of the second flux linkage of the mth period is:

wherein p represents the derivative operator,respectively representing the alpha-axis component and the beta-axis component of the second magnetic linkage of the Mth period under the two-phase static coordinate system, < ->Represents the rotation speed of the M-1 th period, L _m，M 、τ _r，M Mutual inductance of the M-th period, rotor time constant of the M-th period, i _sα，M 、i _sβ，M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the Mth period under a two-phase static coordinate system, < ->Respectively represent the Mth-1 period of the first flux linkage in two stationary coordinates of the two phases of the alpha-axis component, the beta-axis component,/v>The second flux linkage respectively represents the alpha axis component and the beta axis component, K of the M-1 period under the two-phase static coordinate system ₂ Representing a second feedback matrix, k _2α 、k _2β Representing the feedback coefficients of the second feedback matrix.

In application, the rotor time constant of the asynchronous motor can be calculated according to the mutual inductance of the asynchronous motor, and the first feedback matrix and the second feedback matrix are feedback gain matrices.

In application, the same principle as that of the first flux linkage of the M-th period is obtained according to the stator phase voltage, the stator phase current, the rotor inductance, the mutual inductance and the total leakage inductance of the period, the stator resistance of the M-2 th period, the first flux linkage of the M-2 th period and the second flux linkage of the M-2 th period; the second flux linkage of the M-1 th period is obtained according to stator phase current, mutual inductance and rotor time constant of the period, and rotation speed of the M-2 th period, the first flux linkage of the M-2 th period and the second flux linkage of the M-2 th period. Since the 0 th asynchronous motor control period is when the periodic control of the asynchronous motor is not started yet, all parameters of the 0 th asynchronous motor control period which need to be used can be 0 or set values which are set in advance according to actual needs.

In the application, the calculation formula of the first flux linkage is an expression of a first flux linkage calculation model, the calculation formula of the second flux linkage is an expression of a second flux linkage calculation model, the calculation process of the first flux linkage in the M-1 th period needs to be used for the first flux linkage obtained based on the first flux linkage calculation model and the second flux linkage obtained based on the second flux linkage calculation model, and correspondingly, the calculation process of the second flux linkage in the M-1 th period needs to be used for the first flux linkage obtained based on the first flux linkage calculation model and the second flux linkage obtained based on the second flux linkage calculation model.

And step 103, obtaining the stator resistance of the Mth period according to the error between the first flux linkage of the Mth period and the second flux linkage of the Mth period and the stator phase current of the Mth period.

In the application, after the estimated value of the first flux linkage and the estimated value of the second flux linkage in the Mth period are obtained, the error between the estimated value of the first flux linkage and the estimated value of the second flux linkage can be further calculated, then the error and the stator phase current are subjected to cross multiplication or dot multiplication, then integration is carried out, and the estimated value of the stator resistance of the asynchronous motor is obtained based on a rotating speed self-adaption mechanism. The integration operation may be implemented by an integrator or a proportional integrator.

In one embodiment, step S103 includes:

the error between the first flux linkage of the Mth period and the second flux linkage of the Mth period is subjected to cross multiplication with the stator phase current of the Mth period, and a first input value is obtained;

integrating the first input value to obtain a stator resistor of an Mth period;

or, performing point multiplication on the error between the first flux linkage of the Mth period and the second flux linkage of the Mth period and the stator phase current of the Mth period to obtain a second input value;

and integrating the second input value to obtain the stator resistance of the M period.

In an application, the first input value is a value obtained after cross-multiplying an error between the estimated value of the first flux linkage and the estimated value of the second flux linkage with the stator phase current for use as an input parameter of the integrator or the proportional integrator. The second input value is a value obtained by dot multiplying an error between the estimated value of the first flux linkage and the estimated value of the second flux linkage and the stator phase current, and is used as an input parameter of the integrator or the proportional integrator.

In one embodiment, the calculation formula of the first input value is:

the calculation formula of the second input value is as follows:

wherein,transposed matrix representing error between first and second flux linkages for mth period, i _s,M Stator phase current representing the mth cycle, +.>Respectively representing the alpha-axis component and the beta-axis component of the first magnetic linkage of the Mth period under the two-phase static coordinate system, +.>Respectively representing the alpha-axis component, the beta-axis component and the i of the second magnetic linkage of the Mth period under a two-phase static coordinate system _sα，M 、i _sβ，M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the Mth period under a two-phase static coordinate system.

Step S104, obtaining a third flux linkage of the Mth period according to the first flux linkage of the Mth period and the second flux linkage of the Mth period, and entering steps S105 and S106.

In application, after the estimated value of the first flux linkage of the Mth period and the estimated value of the second flux linkage of the Mth period are obtained, fusion processing can be further carried out on the estimated value of the first flux linkage and the estimated value of the second flux linkage, and the estimated value of the third flux linkage of the Mth period is obtained. In each asynchronous motor control period, the estimated value of the first flux linkage and the estimated value of the second flux linkage can be weighted average or filtered to obtain the estimated value of the third flux linkage. The estimated value of the first flux linkage and the estimated value of the second flux linkage are initial estimated values of flux linkages, and the third flux linkage is final estimated value of flux linkages.

In one embodiment, step S104 includes:

carrying out weighted average on the first flux linkage of the Mth period and the second flux linkage of the Mth period to obtain a third flux linkage of the Mth period;

or, performing high-pass filtering on one of the first flux linkage of the Mth period and the second flux linkage of the Mth period, and performing low-pass filtering on the other one to obtain a third flux linkage of the Mth period.

In one embodiment, the calculation formula of the third flux linkage of the mth period is:

wherein,a third flux linkage respectively representing an Mth period, a first flux linkage of the Mth period, and a second flux linkage of the Mth period, f ₁ 、f ₂ Sub-function terms representing weighted average functions corresponding to weighting coefficients 1-m, respectively, 0.ltoreq.m.ltoreq.1, or f ₁ 、f ₂ The other one representing a high pass filter function and the other one representing a low pass filter function.

In one embodiment, f ₁ 、f ₂ The calculation formula of the third flux linkage of the M-th period is as follows:

step S105, according to the third flux linkage of the Mth period, the flux linkage angle of the Mth period and the stator frequency of the Mth period are obtained, and the steps S107 and S108 are carried out.

In an application, after obtaining the estimated value of the third flux linkage, further obtaining an estimated value of the flux linkage angle and an estimated value of the stator frequency according to the estimated value of the third flux linkage. The third flux linkage can be input into a phase-locked loop to obtain the flux linkage angle and the stator frequency output by the phase-locked loop; the alpha axis component and the beta axis component of the third flux linkage under the two-phase static coordinate system can be reversely cut to obtain the flux linkage angle, then the flux linkage angle is processed based on the transfer function of the first-order high-pass filter to obtain the stator frequency, or the flux linkage angle is sequentially subjected to differential and low-pass filtering to obtain the stator frequency.

In one embodiment, step S105 includes:

obtaining the flux linkage angle of the Mth period and the stator frequency of the Mth period through a phase-locked loop according to the third flux linkage of the Mth period;

or, obtaining the inverse cut value of the alpha axis component and the beta axis component of the third flux linkage of the M period under a two-phase static coordinate system to obtain the flux linkage angle of the M period;

obtaining the stator frequency of the Mth period according to the transfer function of the first-order high-pass filter and the flux linkage angle of the Mth period;

or, obtaining the inverse cut value of the alpha axis component and the beta axis component of the third flux linkage of the M period under a two-phase static coordinate system, and obtaining the flux linkage angle of the M period;

and sequentially carrying out differentiation and low-pass filtering on the flux linkage angle of the M-th period to obtain the stator frequency of the M-th period.

In one embodiment, the calculation formula of the flux linkage angle of the mth period is:

wherein,the flux linkage angle, tan, representing the Mth period ^-1 Representing the inverse tangent function, ++>Respectively representing an alpha-axis component and a beta-axis component of the third flux linkage of the Mth period under a two-phase static coordinate system.

In one embodiment, the calculation formula of the stator frequency of the mth period is:

wherein,respectively represent the stator frequency of the Mth period, the flux linkage angle of the Mth period and omega _c Representing the cut-off frequency of the first order high pass filter, s representing the s term of the transfer function of the first order high pass filter.

Step S106, obtaining the slip frequency of the Mth period according to the stator phase current of the Mth period and the third flux linkage of the Mth period, and proceeding to step S107.

In an application, after obtaining the estimated value of the third flux linkage, further obtaining an estimated value of the slip frequency according to the estimated value of the third flux linkage and the detected stator phase current.

In one embodiment, the calculation formula of the slip frequency of the mth period is:

wherein,L _m，M 、τ _r，M respectively representing the slip frequency of the Mth period, the mutual inductance of the Mth period, the rotor time constant of the Mth period, < ->Respectively representing the alpha-axis component, the beta-axis component and the i of the third flux linkage of the M-th period under a two-phase static coordinate system _sα，M 、i _sβ，M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the Mth period under a two-phase static coordinate system.

Step S107, obtaining the rotation speed of the Mth period according to the stator frequency of the Mth period and the slip frequency of the Mth period, and proceeding to step S108.

In an application, after obtaining the estimated value of the stator frequency and the estimated value of the slip frequency, the estimated value of the rotational speed is further obtained from the estimated value of the stator frequency and the estimated value of the slip frequency. The estimated value of the rotational speed is the difference between the estimated value of the stator frequency and the estimated value of the slip frequency.

In one embodiment, the calculation formula of the rotation speed of the mth period is:

wherein,the rotation speed of the mth period, the stator frequency of the mth period, and the slip frequency of the mth period are respectively represented. />

And S108, carrying out feedback control on the asynchronous motor in the M+1th period according to the flux linkage angle of the M period and the rotating speed of the M period.

In the application, the motor controller adjusts the stator phase voltage required to be applied to the stator in the next period according to the estimated value of the flux linkage angle and the estimated value of the rotating speed obtained in the current period, so as to perform feedback control on the actual rotating speed of the asynchronous motor in the next period.

In one embodiment, after step S107 and before step S108, the method further includes:

and carrying out low-pass filtering on the rotating speed of the Mth period.

In the application, before the motor controller performs feedback control on the asynchronous motor according to the estimated value of the rotating speed, the estimated value of the rotating speed can be subjected to low-pass filtering through a low-pass filter so as to filter high-frequency interference signals in the estimated value of the rotating speed, thereby improving the control precision and reliability of the asynchronous motor.

It should be understood that flux linkage in embodiments of the present application refers to rotor flux linkage. The M-1 th cycle, the M-th cycle and the M+1 th cycle can also be three continuous time periods in one asynchronous motor control cycle, or the M-1 th cycle and the M-th cycle can be combined into a longer cycle, so that the M-1 th cycle, the M-th cycle and the M+1 th cycle can be equivalent to two cycles, and the duration of one cycle is equal to the sum of the duration of the M-1 th cycle and the M-th cycle. For any period, if the parameter of the previous period is needed in calculating the parameter of the period, the parameters can be obtained in the previous period or set values set in advance according to actual needs can be directly used, so that the parameter is not required to be obtained in a period.

As shown in fig. 2, the second method for controlling an asynchronous motor according to the embodiment of the present application includes steps S201 to S206 as follows:

step S201, according to the stator phase voltage and the stator phase current of the N period, the first flux linkage of the N-1 period and the second flux linkage of the N-1 period, the first flux linkage of the N period is obtained, and the steps S203 and S204 are entered;

step S202, obtaining a second flux linkage of the N-th period according to the stator phase current of the N-th period, the rotating speed of the N-1-th period, the mutual inductance of the N-1-th period, the first flux linkage of the N-1-th period and the second flux linkage of the N-1-th period, and entering steps S203 and S204.

In the application, N is any positive integer, the Nth period can be any asynchronous motor control period, for example, the Nth period can be the current asynchronous motor control period, and the N-1 th period is the last asynchronous motor control period before the current asynchronous motor control period. When N is 1, the nth cycle is the 1 st asynchronous motor control cycle, the (N-1) th cycle is the 0 th asynchronous motor control cycle, and the 0 th asynchronous motor control cycle is when the periodic control of the asynchronous motor is not started yet, so that the rotating speed, the first magnetic linkage and the second magnetic linkage of the 0 th asynchronous motor control cycle can be 0 or set values set according to actual needs in advance. For an asynchronous motor provided with a rotation speed sensor, the rotation speed of the 0 th asynchronous motor control period can also be detected by the rotation speed sensor.

In application, the first flux linkage of the N-1 th period is obtained according to the stator phase voltage of the N-1 th period and the stator phase current of the N-1 th period, and the first flux linkage of the N-2 th period and the second flux linkage of the N-2 th period, which are the same as the obtaining principle of the first flux linkage of the N-th period; similarly, the second flux linkage of the N-1 th period is obtained according to the stator phase current of the N-1 th period, the rotating speed of the N-2 th period, the mutual inductance of the N-2 th period, the first flux linkage of the N-2 th period and the second flux linkage of the N-2 th period, which are the same as the obtaining principle of the second flux linkage of the N-th period.

In one embodiment, step S201 includes:

the first flux linkage of the N-th period is obtained according to the stator phase voltage of the N-th period, the stator phase current of the N-th period, the rotor inductance of the N-th period, the mutual inductance of the N-th period, the total leakage inductance of the N-th period, the stator resistance of the N-th period, the first flux linkage of the N-1-th period and the second flux linkage of the N-1-th period.

In use, the first flux linkage of the N-th cycle is obtained in particular from the stator phase voltage, stator phase current, rotor inductance, mutual inductance, total leakage inductance and stator resistance of the cycle, and the first flux linkage of the N-1 th cycle and the second flux linkage of the N-1 th cycle.

In one embodiment, the calculation formula of the first flux linkage of the nth period is:

wherein p represents the derivative operator,respectively representing an alpha-axis component, a beta-axis component and L of the first flux linkage of the N-th period under a two-phase static coordinate system _r，N 、L _m，N 、L _σ，N 、R _s，N Respectively representing the rotor inductance of the N-th period, the mutual inductance of the N-th period, the total leakage inductance of the N-th period and the stator resistance of the N-th period, v _sα，N 、v _sβ，N Respectively representing the alpha-axis component, the beta-axis component and the i of the stator phase voltage of the N period under a two-phase static coordinate system _sα，N 、i _sβ，N Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the N-th period under a two-phase static coordinate system, < ->The first flux linkage of the N-1 th period is respectively represented by an alpha axis component and a beta axis component under a two-phase static coordinate system, +.>Respectively representing an alpha axis component and a beta axis component of the second magnetic linkage of the N-1 period under a two-phase static coordinate system, K ₁ Representing a first feedback matrix, k _1α 、k _1β Representing the feedback coefficients of the first feedback matrix.

In one embodiment, step S202 includes:

and obtaining the second flux linkage of the N-th period according to the stator phase current of the N-th period, the rotating speed of the N-1-th period, the mutual inductance of the N-1-th period, the rotor time constant of the N-1-th period, the first flux linkage of the N-1-th period and the second flux linkage of the N-1-th period.

In application, the second flux linkage of the N-th period is obtained according to the stator phase current of the period, the rotating speed of the N-1 th period, the mutual inductance of the N-1 th period, the rotor time constant of the N-1 th period, the first flux linkage of the N-1 th period and the second flux linkage of the N-1 th period.

In one embodiment, the calculation formula of the second flux linkage of the nth cycle is:

wherein p represents the derivative operator,respectively representing the alpha-axis component and the beta-axis component of the second magnetic linkage of the N period under the two-phase static coordinate system, < >>Respectively representing the rotating speed of the N-1 th period, the mutual inductance of the N-1 th period and the rotor time constant of the N-1 th period, i _sα，N 、i _sβ，N Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the N-th period under a two-phase static coordinate system, < ->The first flux linkage of the N-1 th period is respectively represented by an alpha axis component and a beta axis component under a two-phase static coordinate system, +.>Respectively representing an alpha axis component and a beta axis component of the second magnetic linkage of the N-1 period under a two-phase static coordinate system, K ₂ Representing a second feedback matrix, k _2α 、k _2β Representing the feedback coefficients of the second feedback matrix.

In application, the same principle as the acquisition of the first flux linkage of the N-1 th period is adopted, and the first flux linkage of the N-1 th period is specifically obtained according to the stator phase voltage of the N-1 th period, the stator phase current of the N-1 th period, the rotor inductance of the N-1 th period, the mutual inductance of the N-1 th period, the total leakage inductance of the N-1 th period and the stator resistance of the N-1 th period, and the first flux linkage of the N-2 th period and the second flux linkage of the N-2 th period; the second flux linkage of the N-1 th period is obtained according to the stator phase current of the N-2 th period, the mutual inductance of the N-2 th period, the rotor time constant of the N-2 th period, the first flux linkage of the N-2 th period and the second flux linkage of the N-3 rd period. Since the 0 th asynchronous motor control period is when the periodic control of the asynchronous motor is not started yet, all parameters of the 0 th asynchronous motor control period which need to be used can be 0 or set values which are set in advance according to actual needs.

In the application, the calculation formula of the first flux linkage is an expression of a first flux linkage calculation model, the calculation formula of the second flux linkage is an expression of a second flux linkage calculation model, the calculation process of the first flux linkage in the N-1 th period needs to use the first flux linkage obtained based on the first flux linkage calculation model and the second flux linkage obtained based on the second flux linkage calculation model, and correspondingly, the calculation process of the second flux linkage in the N-1 th period needs to use the first flux linkage obtained based on the first flux linkage calculation model and the second flux linkage obtained based on the second flux linkage calculation model.

Step S203, obtaining the mutual inductance of the nth cycle according to the error between the first flux linkage of the nth cycle and the second flux linkage of the nth cycle and the stator phase current of the nth cycle.

In the application, after the estimated value of the first flux linkage and the estimated value of the second flux linkage in the N-th period are obtained, the error between the estimated value of the first flux linkage and the estimated value of the second flux linkage can be further calculated, then the error and the stator phase current are subjected to cross multiplication or point multiplication, then integration is carried out, and the estimated value of the mutual inductance of the asynchronous motor is obtained based on a rotating speed self-adaption mechanism. The integration operation may be implemented by an integrator or a proportional integrator.

In one embodiment, step S203 includes:

the error between the first flux linkage of the N period and the second flux linkage of the N period is subjected to cross multiplication with the stator phase current of the N period, and a first input value is obtained;

integrating the first input value to obtain the mutual inductance of the N period;

or, performing point multiplication on the error between the first flux linkage of the N-th period and the second flux linkage of the N-th period and the stator phase current of the N-th period to obtain a second input value;

and integrating the second input value to obtain the mutual inductance of the N period.

Step S204, according to the first flux linkage of the N-th period and the second flux linkage of the N-th period, obtaining a third flux linkage of the N-th period, and proceeding to steps S205 and S206.

In application, after the estimated value of the first flux linkage and the estimated value of the second flux linkage in the nth period are obtained, fusion processing can be further performed on the estimated value of the first flux linkage and the estimated value of the second flux linkage, so as to obtain the estimated value of the third flux linkage in the nth period. In each asynchronous motor control period, the estimated value of the first flux linkage and the estimated value of the second flux linkage can be weighted average or filtered to obtain the estimated value of the third flux linkage. The estimated value of the first flux linkage and the estimated value of the second flux linkage are initial estimated values of flux linkages, and the third flux linkage is final estimated value of flux linkages.

In one embodiment, step S204 includes:

carrying out weighted average on the first flux linkage of the N-th period and the second flux linkage of the N-th period to obtain a third flux linkage of the N-th period;

or, performing high-pass filtering on one of the first flux linkage of the N-th period and the second flux linkage of the N-th period, and performing low-pass filtering on the other one to obtain a third flux linkage of the N-th period.

In one embodiment, the calculation formula of the third flux linkage of the nth cycle is:

wherein,a third flux linkage respectively representing an N-th period, a first flux linkage of the N-th period, and a second flux linkage of the N-th period, f ₁ 、f ₂ Sub-function terms representing weighted average functions corresponding to weighting coefficients 1-m, respectively, 0.ltoreq.m.ltoreq.1, or f ₁ 、f ₂ The other one representing a high pass filter function and the other one representing a low pass filter function.

In one embodiment, f ₁ 、f ₂ The calculation formula of the third flux linkage of the N period is as follows:

step S205, according to the third flux linkage of the N-th period, obtaining the flux linkage angle of the N-th period and the stator frequency of the N-th period, and proceeding to steps S207 and S208.

In one embodiment, step S205 includes:

obtaining a flux linkage angle of the N period and a stator frequency of the N period through a phase-locked loop according to the third flux linkage of the N period;

or, obtaining the inverse cut value of the alpha axis component and the beta axis component of the third flux linkage of the N-th period under a two-phase static coordinate system to obtain the flux linkage angle of the N-th period;

according to the transfer function of the first-order high-pass filter and the flux linkage angle of the N-th period, the stator frequency of the N-th period is obtained;

or, obtaining the inverse cut value of the alpha axis component and the beta axis component of the third flux linkage of the N period under the two-phase static coordinate system to obtain the flux linkage angle of the N period;

and sequentially carrying out differentiation and low-pass filtering on the flux linkage angle of the N period to obtain the stator frequency of the N period.

In one embodiment, the calculation formula of the flux linkage angle of the nth period is:

wherein,the flux linkage angle, tan, of the N-th period ^-1 Representing the inverse tangent function, ++>Respectively representing an alpha-axis component and a beta-axis component of the third flux linkage of the N period under a two-phase static coordinate system.

In one embodiment, the calculation formula of the stator frequency of the nth period is:

wherein,respectively represent the stator frequency of the N-th period, the flux linkage angle of the N-th period and omega _c Representing first orderThe cut-off frequency of the high pass filter, s, represents the s term of the transfer function of the first order high pass filter. />

Step S206, obtaining the slip frequency of the N-th period according to the stator phase current of the N-th period and the third flux linkage of the N-th period, and proceeding to step S207.

In one embodiment, the calculation formula of the slip frequency of the nth period is:

wherein,L _m，M 、τ _r，M respectively representing the slip frequency of the nth period, the mutual inductance of the nth period, the rotor time constant of the nth period, +.>Respectively representing the alpha-axis component, the beta-axis component and the i of the third flux linkage of the N period under a two-phase static coordinate system _sα，M 、i _sβ，M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the N-th period under a two-phase static coordinate system.

Step S207, according to the stator frequency of the Nth period and the slip frequency of the Nth period, the rotating speed of the Nth period is obtained, and the step S208 is performed.

In one embodiment, the calculation formula of the rotation speed of the nth cycle is:

wherein,the rotation speed of the nth cycle, the stator frequency of the nth cycle, and the slip frequency of the nth cycle are respectively represented.

And step S208, carrying out feedback control on the asynchronous motor in the (n+1) th period according to the flux linkage angle of the (N) th period and the speed for rotating the (N) th period.

In one embodiment, after step S207 and before step S208, the method further comprises:

and carrying out low-pass filtering on the rotating speed of the N period.

It should be understood that flux linkage in embodiments of the present application refers to rotor flux linkage. The N-1 th cycle, the N-th cycle and the n+1 th cycle may be three consecutive periods in one asynchronous motor control cycle, or the N-1 th cycle and the N-th cycle may be combined into one longer cycle, so that the N-1 th cycle, the N-th cycle and the n+1 th cycle may be equivalently two cycles, wherein the duration of one cycle is equal to the sum of the durations of the N-1 th cycle and the N-th cycle. For any period, if the parameter of the previous period is needed in calculating the parameter of the period, the parameters can be obtained in the previous period or set values set in advance according to actual needs can be directly used, so that the parameter is not required to be obtained in a period.

It should be understood that the sequence number of each step in the foregoing embodiment does not mean that the execution sequence of each process should be determined by the function and the internal logic, and should not limit the implementation process of the embodiment of the present application.

As shown in fig. 3, the third method for controlling an asynchronous motor according to the embodiment of the present application includes the following steps S301 to S303:

step S301, acquiring time; if the time is in the first time period, step S302 is entered; if the time is in the second time period, the step S303 is entered;

step S302, executing the steps of the first asynchronous motor control method provided by the embodiment of the application in a first time period;

step S303, executing the steps of the second asynchronous motor control method provided by the embodiment of the application in a second time period.

In application, the asynchronous motor controller can execute the first asynchronous motor control method and the second asynchronous motor control method in a time-division manner, the duration of the first time period is required to be greater than or equal to the Mth period, and the duration of the second time period is required to be greater than or equal to the Nth period. If the time is in the first time period, executing a first asynchronous motor control method in the first time period, and correspondingly, when executing the first asynchronous motor control method, the Mth period is necessarily in the first time period, the Mth period may be in the first time period or not, when the Mth period is not in the first time period, the Mth period may be executed by a second asynchronous motor control method, and when executing the first asynchronous motor control method, if the parameters of the Mth period are needed, the parameters of the Mth period are obtained based on the asynchronous motor control method adopted in the Mth period; similarly, if the time is in the second time period, the second asynchronous motor control method is executed in the second time period, and correspondingly, when the second asynchronous motor control method is executed, the nth cycle is necessarily in the second time period, the nth-1 cycle may be in the second time period or not in the second time period, when the nth-1 cycle is not in the second time period, the nth-1 cycle may be executed as the first asynchronous motor control method, and when the second asynchronous motor control method is executed, if the parameter of the nth-1 cycle is needed, the parameter of the nth-1 cycle is obtained based on the asynchronous motor control method adopted in the nth-1 cycle. The time obtained may be the current time or any future time at which the asynchronous motor control method is to be executed.

In one embodiment, the first time period and the second time period are two alternating and consecutive time periods.

In application, the specific time points and duration covered by the first time period and the second time period can be set according to actual needs, and the two time periods can have no association, or can be two time periods which alternately occur and are continuous. If the first time period and the second time period are two alternating and continuous time periods, the motor controller periodically executes the first asynchronous motor control method and the second asynchronous motor control method in a time-sharing mode.

As shown in fig. 4, the fourth asynchronous motor control method provided by the embodiment of the present application includes the following steps S401 to S403:

step S401, obtaining stator frequency; if the stator frequency is lower than the first stator frequency threshold, step S402 is performed; if the stator frequency is higher than the second stator frequency threshold, the step S403 is performed;

step S402, executing the steps of the first asynchronous motor control method provided by the embodiment of the application when the stator frequency is lower than a first stator frequency threshold value;

step S403, executing the step of the second asynchronous motor control method provided by the embodiment of the present application when the stator frequency is higher than the second stator frequency threshold.

In application, the first stator frequency threshold is less than or equal to the second stator frequency threshold, the stator frequency is lower than the first stator frequency threshold in the M-1 th period, and the stator frequency is higher than the second stator frequency threshold in the N-1 th period. The first stator frequency threshold value and the second stator frequency threshold value can be set according to actual needs, and can be equal or different, for example, the value range of the first stator frequency threshold value is 1/10-1/5 of the rated stator frequency of the asynchronous motor, the value range of the second stator frequency threshold value is 1/5-1/4 of the rated stator frequency of the asynchronous motor, and the first stator frequency threshold value and the second stator frequency threshold value can be equal to 1/5 of the rated stator frequency of the asynchronous motor.

In application, when executing the first asynchronous motor control method, acquiring the stator frequency of each period, if the stator frequency is lower than a first stator frequency threshold value, continuing to execute the first asynchronous motor control method, and if the stator frequency is higher than a second stator frequency threshold value, switching to execute a second asynchronous motor control method; similarly, when the second asynchronous motor control method is executed, the stator frequency of each period is obtained, if the stator frequency is higher than a second stator frequency threshold value, the second asynchronous motor control method is continuously executed, and if the stator frequency is lower than a first stator frequency threshold value, the first asynchronous motor control method is executed.

The embodiment of the application also provides a first asynchronous motor control device which is applied to the asynchronous motor controller and is used for executing the steps in the first asynchronous motor control method embodiment. The device may be a virtual device (virtual appliance) in the asynchronous motor controller, operated by a processor of the asynchronous motor controller, or the asynchronous motor controller itself.

As shown in fig. 5, a first asynchronous motor control apparatus 100 according to an embodiment of the present application includes:

a first flux linkage estimation unit 101, configured to obtain a first flux linkage of an mth period according to the stator phase voltage of the mth period and the stator phase current of the mth period, and the stator resistance of the mth-1 period, the first flux linkage of the mth-1 period, and the second flux linkage of the mth-1 period, and enter a stator resistance estimation unit 103 and a third flux linkage estimation unit 104;

a second flux linkage estimation unit 102, configured to obtain a second flux linkage of the mth period according to the stator phase current of the mth period, the rotation speed of the mth period, the first flux linkage of the mth period and the second flux linkage of the mth period, and enter a stator resistance estimation unit 103 and a third flux linkage estimation unit 104;

a stator resistance estimation unit 103, configured to obtain a stator resistance of an mth cycle according to an error between the first flux linkage of the mth cycle and the second flux linkage of the mth cycle, and a stator phase current of the mth cycle;

A third flux linkage estimation unit 104, configured to obtain a third flux linkage of an mth period according to the first flux linkage of the mth period and the second flux linkage of the mth period, and enter a flux linkage angle and stator frequency estimation unit 105 and a slip frequency estimation unit 106;

a first flux linkage angle and stator frequency estimation unit 105, configured to obtain an mth-period flux linkage angle and an mth-period stator frequency according to the mth-period third flux linkage, and enter a rotation speed estimation unit 107 and a feedback control unit 108;

a first slip frequency estimation unit 106, configured to obtain a slip frequency of an mth period according to the stator phase current of the mth period and the third flux linkage of the mth period, and enter a rotational speed estimation unit 107;

a first rotation speed estimation unit 107, configured to obtain a rotation speed of the mth period according to the stator frequency of the mth period and the slip frequency of the mth period, and enter a feedback control unit 108;

a first feedback control unit 108, configured to perform feedback control on the asynchronous motor in an mth+1th period according to the flux linkage angle of the mth period and the rotation speed of the mth period;

wherein M is a positive integer.

In one embodiment, the first asynchronous motor control apparatus further includes:

And the low-pass filtering unit is used for carrying out low-pass filtering on the rotating speed of the Mth period.

In application, each component in the first asynchronous motor control device can be a software program unit, can also be realized by different logic circuits integrated in the processor or independent physical components connected with the processor, and can also be realized by a plurality of distributed processors. For example, the first flux linkage estimation unit and the second flux linkage estimation unit may each include a subtractor or share a subtractor, the stator resistance estimation unit may include a subtractor, a multiplier, and an integrator or a proportional integrator, the flux linkage angle and stator frequency estimation unit may be a phase-locked loop, the rotation speed estimation unit may be a subtractor, the feedback control unit may be a feedback controller, and the low-pass filter unit may be a low-pass filter.

The embodiment of the application also provides a second asynchronous motor control device which is applied to the asynchronous motor controller and is used for executing the steps in the embodiment of the second asynchronous motor control method. The device may be a virtual device (virtual appliance) in the asynchronous motor controller, operated by a processor of the asynchronous motor controller, or the asynchronous motor controller itself.

As shown in fig. 6, a second asynchronous motor control apparatus 200 according to an embodiment of the present application includes:

a fourth flux linkage estimation unit 201, configured to obtain a first flux linkage of an nth period according to the stator phase voltage of the nth period and the stator phase current of the nth period, and the first flux linkage of the nth-1 period and the second flux linkage of the nth-1 period, and enter a mutual inductance estimation unit 203 and a third flux linkage estimation unit 204;

a fifth flux linkage estimation unit 202, configured to obtain a second flux linkage of the nth cycle according to the stator phase current of the nth cycle, the rotation speed of the nth-1 cycle, the mutual inductance of the nth-1 cycle, the first flux linkage of the nth-1 cycle and the second flux linkage of the nth-1 cycle, and enter the mutual inductance estimation unit 203 and the third flux linkage estimation unit 204;

a mutual inductance estimation unit 203, configured to obtain a mutual inductance of an nth cycle according to an error between the first flux linkage of the nth cycle and the second flux linkage of the nth cycle, and a stator phase current of the nth cycle;

a sixth flux linkage estimation unit 204, configured to obtain a third flux linkage of an nth cycle according to the first flux linkage of the nth cycle and the second flux linkage of the nth cycle, and enter a flux linkage angle and stator frequency estimation unit 205 and a slip frequency estimation unit 206;

A second flux linkage angle and stator frequency estimation unit 205, configured to obtain an nth period flux linkage angle and an nth period stator frequency according to the nth period third flux linkage, and enter a rotation speed estimation unit 207 and a feedback control unit 208;

a second slip frequency estimation unit 206, configured to obtain a slip frequency of an nth cycle according to the stator phase current of the nth cycle and the third flux linkage of the nth cycle, and enter a rotation speed estimation unit 207;

a second rotation speed estimation unit 207, configured to obtain a rotation speed of the nth cycle according to the stator frequency of the nth cycle and the slip frequency of the nth cycle, and enter a feedback control unit 208;

a second feedback control unit 208, configured to perform feedback control on the asynchronous motor in the n+1th period according to the flux linkage angle of the nth period and the speed of turning the nth period;

wherein N is a positive integer.

In one embodiment, the second asynchronous motor control apparatus further includes:

and the low-pass filtering unit is used for carrying out low-pass filtering on the rotating speed of the N period.

In application, each component in the second asynchronous motor control device can be a software program unit, can also be realized by different logic circuits integrated in the processor or independent physical components connected with the processor, and can also be realized by a plurality of distributed processors. For example, the first flux linkage estimation unit and the second flux linkage estimation unit may each include a subtracter or share a subtracter, the mutual inductance estimation unit may include a subtracter, a multiplier, and an integrator or a proportional integrator, the flux linkage angle and stator frequency estimation unit may be a phase-locked loop, the rotation speed estimation unit may be a subtracter, the feedback control unit may be a feedback controller, and the low-pass filter unit may be a low-pass filter.

The embodiment of the application also provides a third asynchronous motor control device which is applied to the asynchronous motor controller and is used for executing the steps in the embodiment of the third asynchronous motor control method. The device may be a virtual device (virtual appliance) in the asynchronous motor controller, operated by a processor of the asynchronous motor controller, or the asynchronous motor controller itself.

The third asynchronous motor control device provided by the embodiment of the application comprises:

a first type of asynchronous motor control device and a second type of asynchronous motor control device;

further comprises:

a time acquisition unit configured to:

acquiring time;

applying a first asynchronous motor control device in a first time period;

in a second time period, a second asynchronous motor control device is applied;

a stator frequency acquisition unit configured to:

acquiring stator frequency;

when the stator frequency is lower than a first stator frequency threshold value, a first asynchronous motor control device is applied;

when the stator frequency is higher than a second stator frequency threshold value, a second asynchronous motor control device is applied;

In application, each component in the third asynchronous motor control device can be a software program unit, can also be realized by different logic circuits integrated in the processor or independent physical components connected with the processor, and can also be realized by a plurality of distributed processors. For example, the time acquisition unit may be a timer or a timer; the third flux linkage estimation unit and the sixth flux linkage estimation unit may be the same unit; the stator frequency acquisition unit and the first flux linkage angle and stator frequency estimation unit and the second flux linkage angle and stator frequency estimation unit may be the same unit; the first slip frequency estimation unit and the second slip frequency estimation unit may be the same unit; the first rotational speed estimation unit and the second rotational speed estimation unit may be the same unit; the first feedback control unit and the second feedback control unit may be the same unit.

As shown in fig. 7, a schematic diagram of the logic structure of the first asynchronous motor control system is exemplarily shown, which includes a first feedback gain matrix 301, a second feedback gain matrix 302, a first flux linkage calculation model 303, a second flux linkage calculation model 304, a first subtractor 305, a proportional integrator 306, a multiplier 307, a third flux linkage estimation unit 308, a flux linkage angle and stator frequency estimation unit 309, a slip frequency estimation unit 310, a second subtractor 311, a low-pass filtering unit 312, a feedback control unit 313, and an asynchronous motor 314.

As shown in fig. 8, a schematic logic structure diagram of a second type of asynchronous motor control system is exemplarily shown, which further includes a rotation speed sensor 315, a first switch 316, and a second switch 317 on the basis of the first type of asynchronous motor control system.

As shown in fig. 9, a schematic diagram of a logic structure of a third asynchronous motor control system is exemplarily shown, which includes a first feedback gain matrix 401, a second feedback gain matrix 402, a first flux linkage calculation model 403, a second flux linkage calculation model 404, a first subtractor 405, a proportional integrator 406, a multiplier 407, a third flux linkage estimation unit 408, a flux linkage angle and stator frequency estimation unit 409, a slip frequency estimation unit 410, a second subtractor 411, a low pass filter unit 412, a feedback control unit 413, and an asynchronous motor 414.

As shown in fig. 10, a logic structure diagram of a fourth asynchronous motor control system is exemplarily shown, which further includes a rotation speed sensor 415, a first switch 416, and a second switch 417 on the basis of the first asynchronous motor control system.

In application, the first switch and the second switch are used for realizing the gating function of one or two, and can be realized by a software program unit, an electronic switch tube or a logic gate circuit.

As shown in fig. 11, an embodiment of the present application further provides an asynchronous motor controller 500, including: at least one processor 501 (only one processor is shown in fig. 11), a memory 502, and a computer program 503 stored in the memory 502 and executable on the at least one processor 502, the steps of the various asynchronous motor control method embodiments described above being implemented by the processor 502 when the computer program 503 is executed.

In applications, the asynchronous motor controller may include, but is not limited to, a processor and a memory, and may also include a current sensor, an inverter, a rectifier, an analog-to-digital converter, a high pass filter, a low pass filter, a subtractor, a proportional integrator, a phase locked loop, a switch, and the like. It will be appreciated by those skilled in the art that fig. 11 is merely an example of an asynchronous motor controller and is not meant to be limiting, and may include more or fewer components than shown, or may combine certain components, or may include different components, for example, input-output devices, network access devices, etc. The network access device may comprise a communication module for the asynchronous motor controller to communicate with the user terminal.

In application, the processor may be a central processing unit (Central Processing Unit, CPU), but may also be other general purpose processors, digital signal processors (Digital Signal Processor, DSPs), application specific integrated circuits (Application Specific Integrated Circuit, ASICs), off-the-shelf programmable gate arrays (Field-Programmable Gate Array, FPGAs) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

In applications, the memory may in some embodiments be an internal storage unit of the asynchronous motor controller, such as a hard disk or a memory of the asynchronous motor controller. The memory may in other embodiments also be an external storage device of the asynchronous motor controller, for example, a plug-in hard disk, a Smart Media Card (SMC), a Secure Digital (SD) Card, a Flash Card (Flash Card) or the like, which are provided on the asynchronous motor controller. The memory may also comprise both an internal memory unit and an external memory device of the asynchronous motor controller. The memory is used to store an operating system, application programs, boot Loader (Boot Loader), data, and other programs, etc., such as program code for a computer program, etc. The memory may also be used to temporarily store data that has been output or is to be output.

In application, the communication module may be configured as any device capable of directly or indirectly performing long-distance wired or wireless communication with the client according to actual needs, for example, the communication module may provide a solution of communication including wireless local area network (Wireless Localarea Networks, WLAN) (such as Wi-Fi network), bluetooth, zigbee, mobile communication network, global navigation satellite system (Global Navigation Satellite System, GNSS), frequency modulation (Frequency Modulation, FM), short-distance wireless communication technology (Near Field Communication, NFC), infrared technology (IR), and the like, which are applied to the network device. The communication module may include an antenna, which may have only one element, or may be an antenna array including a plurality of elements. The communication module can receive electromagnetic waves through the antenna, frequency-modulate and filter the electromagnetic wave signals, and send the processed signals to the processor. The communication module can also receive the signal to be transmitted from the processor, frequency modulate and amplify the signal, and convert the signal into electromagnetic waves through the antenna to radiate.

In application, the low-pass filter may be any type of filter with a cut-off frequency that is satisfactory, for example, a butterworth filter (Butterworth filter) or a chebyshev filter, as the case may be.

In application, the analog-to-digital converter can select any type of analog-to-digital converter with sampling precision meeting the requirement according to actual needs, for example, a parallel comparison type, a successive approximation type or a double integration type analog-to-digital converter. The sampling accuracy of the analog-to-digital converter is determined by the resolution thereof, and the resolution can be selected according to actual needs, for example, eight bits, twelve bits or twenty-four bits. When the analog-to-digital converter with switchable resolution is selected, a user can switch the resolution of the analog-to-digital converter through a man-machine interaction device of an asynchronous motor controller or a user terminal according to actual needs so as to adapt to different application scenes.

It should be noted that, because the content of information interaction and execution process between the above devices/modules is based on the same concept as the method embodiment of the present application, specific functions and technical effects thereof may be referred to in the method embodiment section, and will not be described herein.

It will be apparent to those skilled in the art that, for convenience and brevity of description, only the above-described division of the functional modules is illustrated, and in practical application, the above-described functional allocation may be performed by different functional modules according to needs, i.e. the internal structure of the apparatus is divided into different functional modules to perform all or part of the functions described above. The functional modules in the embodiment may be integrated in one processing module, or each module may exist alone physically, or two or more modules may be integrated in one module, where the integrated modules may be implemented in a form of hardware or a form of software functional modules. In addition, the specific names of the functional modules are only for distinguishing from each other, and are not used for limiting the protection scope of the present application. The specific working process of the modules in the above system may refer to the corresponding process in the foregoing method embodiment, which is not described herein again.

The embodiments of the present application also provide a computer readable storage medium, in which a computer program is stored, where the computer program, when executed by a processor, may implement the steps of the above-mentioned method embodiments.

Embodiments of the present application provide a computer program product enabling an asynchronous motor controller to carry out the steps of the method embodiments described above when the computer program product is run on the asynchronous motor controller.

The integrated modules, if implemented in the form of software functional modules and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the present application may implement all or part of the flow of the method of the above-described embodiments, and may be implemented by a computer program to instruct related hardware, where the computer program may be stored in a computer readable storage medium, and when the computer program is executed by a processor, the computer program may implement the steps of the method embodiments described above. Wherein the computer program comprises computer program code which may be in source code form, object code form, executable file or some intermediate form etc. The computer readable medium may include at least: any entity or device capable of carrying computer program code to the asynchronous motor controller, recording medium, computer Memory, read-Only Memory (ROM), random access Memory (RAM, random Access Memory), electrical carrier signals, telecommunications signals, and software distribution media. Such as a U-disk, removable hard disk, magnetic or optical disk, etc.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and in part, not described or illustrated in any particular embodiment, reference is made to the related descriptions of other embodiments.

Those of ordinary skill in the art will appreciate that the various illustrative modules 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 depends 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 present application.

In the embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the apparatus embodiments described above are merely illustrative, and for example, the division of the modules is merely a logical function division, and there may be additional divisions when actually implemented, for example, multiple modules or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection via interfaces, devices or modules, which may be in electrical, mechanical or other forms.

The modules described as separate components may or may not be physically separate, and components shown as modules may or may not be physical modules, i.e., may be located in one place, or may be distributed over a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

The above embodiments are only for illustrating the technical solution of the present application, and not for limiting the same; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. An asynchronous motor control method, comprising:

wherein M is a positive integer.

2. The method of controlling an asynchronous motor according to claim 1, wherein the obtaining the first flux linkage of the mth period based on the stator phase voltage of the mth period and the stator phase current of the mth period, and the stator resistance of the mth-1 period, the first flux linkage of the mth-1 period, and the second flux linkage of the mth-1 period, comprises:

3. The method for controlling an asynchronous motor according to claim 2, wherein the calculation formula of the first flux linkage of the mth period is:

wherein p represents the derivative operator,respectively representing an alpha axis component and a beta axis component of the first flux linkage of the Mth period in a two-phase stationary coordinate system, L _r,M 、L _m,M 、L _σ,Mp Respectively represent the rotor inductance of the Mth period, the mutual inductance of the Mth period and the Mth periodTotal leakage inductance, v _sα,M 、v _sβ,M Respectively representing the alpha-axis component and the beta-axis component of the stator phase voltage of the Mth period in a two-phase stationary coordinate system, < >>Stator inductance, i, representing the M-1 th period _sα,M 、i _sβ,M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the Mth period in a two-phase stationary coordinate system, +.>The first flux linkage respectively represents the alpha axis component and the beta axis component of the M-1 period under the two-phase static coordinate system, +.>Respectively representing an alpha axis component and a beta axis component of the second flux linkage of the M-1 th period under a two-phase static coordinate system, K ₁ Representing a first feedback matrix, k _1α 、k _1β Representing the feedback coefficients of the first feedback matrix.

4. The method of claim 1, wherein the obtaining the second flux linkage of the mth cycle based on the stator phase current of the mth cycle, and the rotational speed of the mth-1 cycle, the first flux linkage of the mth-1 cycle, and the second flux linkage of the mth-1 cycle, comprises:

5. The method of claim 4, wherein the calculation formula of the second flux linkage of the mth period is:

wherein p represents the derivative operator,respectively representing the alpha-axis component and the beta-axis component of the second magnetic linkage of the Mth period under the two-phase static coordinate system, < ->Represents the rotation speed of the M-1 th period, L _m,M 、τ _r,M Mutual inductance of the M-th period, rotor time constant of the M-th period, i _sα,M 、i _sβ,M Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the Mth period under a two-phase static coordinate system, < ->The first flux linkage respectively represents the alpha axis component and the beta axis component of the M-1 period under the two-phase static coordinate system, +. >Respectively representing an alpha axis component and a beta axis component of the second magnetic linkage of the M-1 period under a two-phase static coordinate system, K ₂ Representing a second feedback matrix, k _2α 、k _2β Representing the feedback coefficients of the second feedback matrix.

6. The method of controlling an asynchronous motor according to claim 1, wherein the obtaining the stator resistance of the mth cycle based on an error between the first flux linkage of the mth cycle and the second flux linkage of the mth cycle, and the stator phase current of the mth cycle, comprises:

integrating the first input value to obtain a stator resistor of an Mth period;

7. An asynchronous motor control method, comprising:

wherein N is a positive integer.

8. The method of controlling an asynchronous motor according to claim 7, wherein the obtaining the first flux linkage of the nth period based on the stator phase voltage of the nth period and the stator phase current of the nth period, and the first flux linkage of the N-1 th period and the second flux linkage of the N-1 th period, comprises:

9. The method of claim 8, wherein the calculation formula of the first flux linkage of the nth period is:

wherein p represents the derivative operator,respectively representing an alpha-axis component, a beta-axis component and L of the first flux linkage of the N-th period under a two-phase static coordinate system _r,N 、L _m,N 、L _σ,N 、R _s,N Respectively representing the rotor inductance of the N-th period, the mutual inductance of the N-th period, the total leakage inductance of the N-th period and the stator resistance of the N-th period, v _sα,N 、v _sβ,N Respectively representing the alpha-axis component, the beta-axis component and the i of the stator phase voltage of the N period under a two-phase static coordinate system _sα,N 、i _sβ,N Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the N-th period under a two-phase static coordinate system, < ->The first flux linkage of the N-1 th period is respectively represented by an alpha axis component and a beta axis component under a two-phase static coordinate system, +.>Respectively representing alpha-axis component, beta-axis component and k of second magnetic linkage of N-1 period under two-phase static coordinate system ₁ Representing a first feedback matrix, k _1α 、k _1β Representing the feedback coefficients of the first feedback matrix.

10. The method of claim 7, wherein the obtaining the second flux linkage of the nth cycle based on the stator phase current of the nth cycle and the rotation speed of the nth-1 cycle, the mutual inductance of the nth-1 cycle, the first flux linkage of the nth-1 cycle, and the second flux linkage of the nth-1 cycle, comprises:

11. The method of claim 10, wherein the calculation formula of the second flux linkage of the nth period is:

wherein p represents the derivative operator,respectively represents the alpha-axis component of the second magnetic linkage of the N period under a two-phase static coordinate system,Beta-axis component->Respectively representing the rotating speed of the N-1 th period, the mutual inductance of the N-1 th period and the rotor time constant of the N-1 th period, i _sα,N 、i _sβ,N Respectively representing the alpha-axis component and the beta-axis component of the stator phase current of the N-th period under a two-phase static coordinate system, < ->The first flux linkage of the N-1 th period is respectively represented by an alpha axis component and a beta axis component under a two-phase static coordinate system, +. >Respectively representing an alpha axis component and a beta axis component of the second magnetic linkage of the N-1 period under a two-phase static coordinate system, K ₂ Representing a second feedback matrix, k _2α 、k _2β Representing the feedback coefficients of the second feedback matrix.

12. The method of controlling an asynchronous motor according to claim 7, wherein the obtaining the nth period mutual inductance according to an error between the nth period first flux linkage and the nth period second flux linkage and the nth period stator phase current comprises:

or, performing point multiplication on the error between the first flux linkage of the N period and the second flux linkage of the N period and the stator phase current of the N period to obtain a second input value;

13. An asynchronous motor control method, comprising:

in a first period of time, performing the steps of the asynchronous motor control method according to any one of claims 1 to 6;

performing the steps of the asynchronous motor control method according to any one of claims 7 to 12 during a second period of time;

Alternatively, the steps of the asynchronous motor control method according to any one of claims 1 to 6 are performed when the stator frequency is lower than a first stator frequency threshold;

-performing the steps of the asynchronous motor control method according to any of claims 7 to 12 when the stator frequency is higher than a second stator frequency threshold;

14. An asynchronous motor control device, characterized by comprising:

wherein M is a positive integer.

15. An asynchronous motor control device, characterized by comprising:

Wherein N is a positive integer.

16. An asynchronous motor control apparatus comprising the asynchronous motor control apparatus according to claims 14 and 15;

the asynchronous motor control device according to claim 14 is applied during a first period of time;

applying the asynchronous motor control device according to claim 15 for a second period of time;

alternatively, the asynchronous motor control device according to claim 14 is applied when the stator frequency is below a first stator frequency threshold;

applying the asynchronous motor control device according to claim 15 when the stator frequency is higher than a second stator frequency threshold;

17. An asynchronous motor controller comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing the steps of the asynchronous motor control method according to any one of claims 1 to 13 when the computer program is executed.

18. A computer readable storage medium storing a computer program which, when executed by a processor, implements the steps of the asynchronous motor control method according to any one of claims 1 to 13.