Motor quick starting method and system based on predictive current model

Abstract

The invention provides a motor quick starting method and system based on a predictive current model, and relates to the technical field of control, and the method comprises the steps: carrying out the pre-positioning of a rotor in a static state, controlling a motor to enter a starting state, collecting a three-phase current, converting the three-phase current into a rotating coordinate system through coordinate conversion, and starting the motor. Determining gamma-axis actual current and delta-axis actual current in the rotating coordinate system, predicting the gamma-axis current of the rotating coordinate system by using the predicted current model to obtain gamma-axis predicted current, carrying out difference calculation on the gamma-axis predicted current and the gamma-axis actual current to obtain a predicted current error, and constructing a rotor position observer based on the predicted current model to obtain the rotor position of the rotating coordinate system. And S8, inputting the predicted current error into a rotor position observer, determining an estimated rotor position and a rotating speed, respectively sending the estimated rotor position and the rotating speed into a coordinate transformation controller and a rotating speed loop controller, carrying out rotating speed closed-loop control, and repeating the steps S2 to S8 to realize the motor quick start based on the predicted current model.

Description

Technical Field

[0001] The present invention relates to the field of control technology, and in particular to a motor quick starting method and system based on a predicted current model. Background Art

[0002] In recent years, the performance of permanent magnet materials has continued to improve while the cost has continued to decrease, making permanent magnet synchronous motors more and more widely used in transportation, industrial control, energy development and other fields. Permanent magnet synchronous motors have the characteristics of simple structure, high power density, and high operating efficiency, and have good application prospects in various potential electrification fields. Among them, in specific scenarios such as turbocharging and fuel cell air compressors, permanent magnet synchronous motors are designed with air bearings, and their peak speed will exceed 100,000 rpm. Such permanent magnet synchronous motors are generally called ultra-high-speed permanent magnet synchronous motors. Due to the limitations of the air bearing installation method, ultra-high-speed permanent magnet synchronous motors cannot be installed with position sensors, and a position sensorless control system is required to accurately estimate the motor rotor position to ensure the reliable operation of the control system.

[0003] At present, most ultra-high-speed motor control systems use the current-to-frequency ratio control starting method, that is, no position estimation is performed, and the target speed is directly integrated as the position angle in vector control, and current closed-loop control is performed with a fixed current command.

[0004] However, the existing methods cannot fully utilize the torque output capacity of the motor due to inaccurate rotor position estimation, resulting in limited starting acceleration. In addition, it is necessary to design a switching strategy with the medium and high speed rotor position estimation algorithm, which increases the design and implementation complexity of the system and cannot fully meet the performance requirements of the motor for fast starting. Summary of the invention

[0005] In order to solve the technical problem that the existing methods cannot fully utilize the torque output capacity of the motor due to inaccurate rotor position estimation, resulting in limited starting acceleration, and need to design a switching strategy with the medium and high speed rotor position estimation algorithm, which increases the design and implementation complexity of the system and cannot fully meet the performance requirements of the motor for rapid starting, the present invention provides a motor rapid starting method and system based on a predictive current model.

[0006] The technical solution provided by the embodiment of the present invention is as follows:

[0007] First aspect:

[0008] An embodiment of the present invention provides a motor quick starting method based on a predicted current model, comprising:

[0009] S1: Pre-position the rotor in a stationary state to determine the initial position of the rotor;

[0010] S2: Control the motor to enter the starting state and collect three-phase current;

[0011] S3: transforming the three-phase current into a rotating coordinate system through coordinate transformation, and determining an actual current of a γ-axis and an actual current of a δ-axis in the rotating coordinate system;

[0012] S4: predicting the γ-axis current of the rotating coordinate system according to the γ-axis actual current and the δ-axis actual current using a predicted current model to obtain a γ-axis predicted current;

[0013] S5: performing a difference calculation on the γ-axis predicted current and the γ-axis actual current to obtain a predicted current error;

[0014] S6: Construct a rotor position observer based on the predictive current model;

[0015] S7: inputting the predicted current error into the rotor position observer to determine the estimated rotor position and speed;

[0016] S8: sending the estimated rotor position and speed to the coordinate transformation and speed loop controller respectively to perform speed closed-loop control;

[0017] S9: Repeat S2 to S8 to achieve quick start of the motor based on the predicted current model.

[0018] Second aspect:

[0019] An embodiment of the present invention provides a motor rapid starting system based on a predicted current model, comprising:

[0020] A positioning module is used to pre-position the rotor in a stationary state and determine the initial position of the rotor;

[0021] The acquisition module is used to control the motor to enter the starting state and collect the three-phase current;

[0022] A transformation module, used for transforming the three-phase current into a rotating coordinate system through coordinate transformation, and determining an actual current of a γ-axis and an actual current of a δ-axis in the rotating coordinate system;

[0023] A prediction module, used to predict the γ-axis current of the rotating coordinate system according to the γ-axis actual current and the δ-axis actual current by using a prediction current model to obtain a γ-axis predicted current;

[0024] A calculation module, used for performing a difference calculation between the γ-axis predicted current and the γ-axis actual current to obtain a predicted current error;

[0025] A building block for building a rotor position observer based on a predictive current model;

[0026] An input module, configured to input the predicted current error into the rotor position observer to determine an estimated rotor position and speed;

[0027] A control module, used for sending the estimated rotor position and speed to the coordinate transformation and speed loop controller respectively, to perform speed closed-loop control;

[0028] The repeating module is used to repeat S2 to S8 to achieve a quick start of the motor based on a predictive current model.

[0029] The third aspect:

[0030] An embodiment of the present invention provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, the method for quickly starting a motor based on a predicted current model as described in the first aspect is implemented.

[0031] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0032] (1) In the present invention, coordinate transformation is used to transform the three-phase current into a rotating coordinate system, and the actual current of the γ-axis and the actual current of the δ-axis in the rotating coordinate system are determined. According to the actual current of the γ-axis and the actual current of the δ-axis, the γ-axis current of the rotating coordinate system is predicted by using a predicted current model to obtain the predicted current of the γ-axis, and the predicted current of the γ-axis is calculated to be different from the actual current of the γ-axis to obtain the predicted current error. The γ-axis current of the rotating coordinate system is predicted by the predicted current model to improve the estimation accuracy of the rotor position. At the same time, the predicted current error is calculated to correct the position estimation, so that the rotor position estimation is more accurate, thereby improving the torque output capacity of the motor and improving the starting acceleration.

[0033] (2) In the present invention, a rotor position observer based on a predicted current model is constructed, the predicted current error is input into the rotor position observer, the estimated rotor position and speed are determined, and the estimated rotor position and speed are respectively sent to the coordinate transformation and speed loop controller to perform speed closed-loop control. No additional algorithm switching strategy is required, thereby achieving unified control from starting to high-speed stage and meeting the performance requirements of the motor for rapid starting. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0035] Figure 1A schematic flow chart of a method for quickly starting a motor based on a predicted current model provided by an embodiment of the present invention;

[0036] Figure 2 A schematic diagram of the structure of a rotor position observer based on a predictive current model provided in an embodiment of the present invention;

[0037] Figure 3 A schematic structural diagram of a motor rapid starting system based on a predictive current model provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The technical solution of the present invention is described below in conjunction with the accompanying drawings.

[0039] In the embodiments of the present invention, words such as "exemplarily" and "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "example" in the present invention should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of the word "example" is intended to present the concept in a specific way. In addition, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either of the two.

[0040] In the embodiments of the present invention, "image" and "picture" can sometimes be used interchangeably. It should be noted that when the difference between them is not emphasized, the meanings they intend to express are the same. "of", "corresponding, relevant" and "corresponding" can sometimes be used interchangeably. It should be noted that when the difference between them is not emphasized, the meanings they intend to express are the same.

[0041] In the embodiments of the present invention, sometimes a subscript such as W1 may be mistakenly written as a non-subscript such as W1. When the difference is not emphasized, the meanings to be expressed are consistent.

[0042] In order to make the technical problems, technical solutions and advantages to be solved by the present invention more clear, a detailed description will be given below with reference to the accompanying drawings and specific embodiments.

[0043] Reference Manual Attached Figure 1 , showing a flow chart of a method for rapid motor starting based on a predictive current model provided in an embodiment of the present invention.

[0044] Reference Manual Attached Figure 2 , showing a schematic diagram of the structure of a rotor position observer based on a predictive current model provided in an embodiment of the present invention

[0045] The embodiment of the present invention provides a method for quickly starting a motor based on a predicted current model. The method can be implemented by a device for quickly starting a motor based on a predicted current model. The device for quickly starting a motor based on a predicted current model can be a terminal or a server. The processing flow of the method for quickly starting a motor based on a predicted current model can include the following steps:

[0046] S1: Pre-position the rotor in a stationary state to determine the initial position of the rotor.

[0047] In a possible implementation, S1 specifically includes:

[0048] S101: In a stationary state, the rotor position is set to zero, the d-axis current is set to zero, and the q-axis current is set to a constant less than the rated current. Through current closed-loop control for a first preset time, the permanent magnet of the motor reaches a position perpendicular to the horizontal axis of the two-phase stationary coordinate system.

[0049] S102: In a stationary state, the rotor position is set to zero, the q-axis current is set to zero, and the d-axis current is set to a constant less than the rated current. Through a second set time current closed-loop control, the permanent magnet of the motor is made to coincide with the horizontal axis of the two-phase stationary coordinate system to determine the initial position of the rotor.

[0050] It should be noted that those skilled in the art can set the first preset time and the second preset time according to actual needs, and the present invention is not limited thereto.

[0051] In the present invention, by pre-positioning, the error caused by the inaccurate initial position of the rotor during the startup process can be effectively reduced, thereby improving the startup accuracy of the entire system. At the same time, determining the accurate initial position before startup can enable the motor to enter the closed-loop control state more quickly during the startup process, thereby improving the startup response speed and efficiency and shortening the startup time.

[0052] S2: Control the motor to enter the starting state and collect three-phase current.

[0053] S3: The three-phase current is transformed into a rotating coordinate system through coordinate transformation, and the actual current of the γ axis and the actual current of the δ axis in the rotating coordinate system are determined.

[0054] Among them, the main purpose of coordinate transformation is to convert physical quantities such as current and voltage in the three-phase stationary coordinate system into a rotating coordinate system to simplify the control algorithm and improve the control accuracy and response speed.

[0055] The rotating coordinate system is a core concept in motor control, especially vector control. Its main purpose is to transform the three-phase current or voltage signal of the motor stator into a coordinate system fixed relative to the direction of the motor rotor magnetic field, thereby simplifying motor control.

[0056] In a possible implementation, the calculation formula for coordinate transformation is:

[0057]

[0058] Among them, i a 、i b and i c Represents the three-phase current, i α represents the α-axis current, i β represents the β-axis current, i γ represents the γ-axis current, i δ represents the delta axis current, represents the estimated rotor position.

[0059] It should be noted that the estimated rotor position S7 is determined by a rotor position observer based on a predicted current model, and an initial value of the estimated rotor position is 0.

[0060] In the present invention, in the rotating coordinate system, the mathematical model of the motor can be approximated as a DC motor model, which converts the complex AC motor control problem into a simpler DC motor control problem, thereby reducing the complexity of the control algorithm. At the same time, in the rotating coordinate system, the representation of current and voltage is "stationary" relative to the magnetic field of the motor rotor, which helps to reduce the dynamic error of the motor during operation and improve the control accuracy.

[0061] Furthermore, the coordinate transformation method is not only applicable to control under high-speed conditions, but can also provide reasonable control strategies under low-speed conditions, ensuring that the system can maintain good control performance throughout the entire operating range.

[0062] S4: According to the actual current of the γ-axis and the actual current of the δ-axis, the γ-axis current of the rotating coordinate system is predicted using a predicted current model to obtain a predicted γ-axis current.

[0063] Among them, the Predictive Current Model is an advanced control algorithm for motor control, especially suitable for control systems of high-performance motors. It optimizes the control strategy by predicting future current changes to achieve higher control accuracy and dynamic response performance.

[0064] In a possible implementation manner, the calculation formula of the γ-axis predicted current is:

[0065]

[0066] in, represents the predicted γ-axis current at time k+1, i γ (k) represents the actual current of the γ axis at time k, T sRepresents the operation cycle of the algorithm, L s Represents the stator inductance of the motor, R s represents the stator resistance of the motor, ω represents the rotor speed, u γ (k) represents the actual voltage of the γ-axis at time k.

[0067] In the present invention, by accurately predicting the γ-axis current at the next moment, the control signal (such as voltage) can be adjusted in time, thereby improving the accuracy of motor control. At the same time, during the operation of the motor, the fluctuation of current and torque will affect the performance of the motor. By predicting the current model, the controller can better suppress the fluctuation of current and torque during the startup process and at high speed, ensuring the smooth operation of the motor.

[0068] S5: Calculate the difference between the γ-axis predicted current and the γ-axis actual current to obtain a predicted current error.

[0069] In a possible implementation, the calculation formula for the predicted current error is:

[0070]

[0071] Among them, Δi γ represents the predicted current error, represents the predicted γ-axis current at time k+1, i γ (k+1) represents the actual current of the γ-axis at time k+1.

[0072] In the present invention, the error value reflects the deviation between the prediction model and the actual motor state. By analyzing this error, the output of the observer can be dynamically adjusted to gradually reduce the estimation error and improve the accuracy of the rotor position and speed estimation.

[0073] S6: Construct a rotor position observer based on the predictive current model.

[0074] Among them, the rotor position observer based on the predicted current model is an advanced motor control algorithm that aims to accurately estimate the real-time position and speed of the motor rotor. The observer uses the calculation results of the predicted current model to dynamically adjust the estimate of the rotor position, thereby improving the control accuracy and the operating efficiency of the motor.

[0075] In a possible implementation, the rotor position observer based on the predicted current model is specifically:

[0076]

[0077] in, represents the estimated rotor position, t represents time, Δi γ represents the predicted current error, represents the estimated rotor speed, np represents the number of magnetic poles of the motor, J represents the moment of inertia of the motor, T e Represents the output torque of the motor, represents the load torque and disturbance, β1, β2 and β3 represent the gain coefficients of the observer.

[0078] In the present invention, the rotor position observer based on the predictive current model significantly improves the performance of the motor control system through an accurate, robust and low-complexity design.

[0079] S7: Input the predicted current error to the rotor position observer to determine the estimated rotor position and speed.

[0080] In the present invention, by inputting the predicted current error as feedback into the rotor position observer, the estimated values ​​of the rotor position and speed can be corrected in real time, thereby improving the accuracy of the position and speed estimation. This is particularly critical for efficient control of the motor, especially when running at high speeds, accurate rotor position estimation can significantly improve the dynamic response and stability of the motor. At the same time, the observer is based on a simplified formula of the predicted current model, and the calculation is relatively simple, but it can provide high-precision rotor position and speed estimates. This design greatly reduces the complexity of real-time calculations and is suitable for ultra-high-speed motor control systems that have strict requirements on computing resources and execution time.

[0081] S8: The estimated rotor position and speed are sent to the coordinate transformation and speed loop controller respectively to perform speed closed-loop control.

[0082] Among them, the speed loop controller is a key component in the motor control system, which is mainly used to adjust the motor speed to keep it at the set target value. The actual measured speed is compared with the target speed through the feedback loop, and then the control signal is adjusted according to the difference to ensure that the motor runs at the required speed. The speed loop controller is usually used as part of the vector control or direct torque control system and is widely used in various motor drive applications that require precise speed control.

[0083] Specifically, the estimated rotor position and speed obtained by the rotor position observer based on the predictive current model are sent to various modules of the classic double closed-loop control system such as coordinate transformation and speed loop controller for speed closed-loop control.

[0084] In the present invention, by sending the estimated rotor position and speed to the speed loop controller, accurate control of the motor speed can be achieved. At the same time, the speed loop controller can process the speed error in real time and adjust the control signal, so that the motor can quickly respond to load changes or external disturbances and improve dynamic performance.

[0085] Furthermore, in applications that require high dynamic response and high-precision control (such as ultra-high-speed motors), this control method can meet stringent performance requirements and ensure that the motor can run stably even at high speeds.

[0086] S9: Repeat S2 to S8 to achieve quick start of the motor based on the predicted current model.

[0087] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0088] (1) In the present invention, coordinate transformation is used to transform the three-phase current into a rotating coordinate system, and the actual current of the γ-axis and the actual current of the δ-axis in the rotating coordinate system are determined. According to the actual current of the γ-axis and the actual current of the δ-axis, the γ-axis current of the rotating coordinate system is predicted by using a predicted current model to obtain the predicted current of the γ-axis, and the predicted current of the γ-axis is calculated to be different from the actual current of the γ-axis to obtain the predicted current error. The γ-axis current of the rotating coordinate system is predicted by the predicted current model to improve the estimation accuracy of the rotor position. At the same time, the predicted current error is calculated to correct the position estimation, so that the rotor position estimation is more accurate, thereby improving the torque output capacity of the motor and improving the starting acceleration.

[0089] (2) In the present invention, a rotor position observer based on a predicted current model is constructed, the predicted current error is input into the rotor position observer, the estimated rotor position and speed are determined, and the estimated rotor position and speed are respectively sent to the coordinate transformation and speed loop controller to perform speed closed-loop control. No additional algorithm switching strategy is required, thereby achieving unified control from starting to high-speed stage and meeting the performance requirements of the motor for rapid starting.

[0090] Reference Manual Attached Figure 3 , showing a structural schematic diagram of a motor quick starting system based on a predictive current model provided by the present invention.

[0091] The present invention also provides a motor rapid starting system 20 based on a predictive current model, comprising:

[0092] The positioning module 201 is used to pre-position the rotor in a stationary state and determine the initial position of the rotor;

[0093] The acquisition module 202 is used to control the motor to enter the starting state and collect the three-phase current;

[0094] A transformation module 203 is used to transform the three-phase current into a rotating coordinate system through coordinate transformation, and determine the actual current of the γ-axis and the actual current of the δ-axis in the rotating coordinate system;

[0095] A prediction module 204 is used to predict the γ-axis current of the rotating coordinate system according to the γ-axis actual current and the δ-axis actual current by using a prediction current model to obtain a γ-axis predicted current;

[0096] A calculation module 205 is used to perform a difference calculation between the γ-axis predicted current and the γ-axis actual current to obtain a predicted current error;

[0097] A construction module 206 is used to construct a rotor position observer based on a predicted current model;

[0098] An input module 207, configured to input the predicted current error into the rotor position observer to determine an estimated rotor position and speed;

[0099] A control module 208, for sending the estimated rotor position and speed to the coordinate transformation and speed loop controller respectively, to perform speed closed-loop control;

[0100] The repeating module 209 is used to repeat the acquisition module to the control module to achieve the rapid start of the motor based on the predicted current model.

[0101] In a possible implementation manner, the positioning module is specifically used to:

[0102] In a stationary state, the rotor position is set to zero, the d-axis current is set to zero, and the q-axis current is set to a constant less than the rated current, and the permanent magnet of the motor is made to reach a position perpendicular to the horizontal axis of the two-phase stationary coordinate system through current closed-loop control for a first preset time;

[0103] In the stationary state, the rotor position is set to zero, the q-axis current is zero, and the d-axis current is a constant less than the rated current. Through the second setting time current closed-loop control, the permanent magnet of the motor is made to coincide with the horizontal axis of the two-phase stationary coordinate system to determine the initial position of the rotor.

[0104] In a possible implementation, the calculation formula for the coordinate transformation is:

[0105]

[0106]

[0107] Among them, i a 、i b and i c Represents the three-phase current, i α represents the α-axis current, i β represents the β-axis current, i γ represents the γ-axis current, i δ represents the delta axis current, represents the estimated rotor position.

[0108] In a possible implementation manner, the calculation formula of the γ-axis predicted current is:

[0109]

[0110] in, represents the predicted γ-axis current at time k+1, i γ (k) represents the actual current of the γ axis at time k, T s Represents the operation cycle of the algorithm, L s Represents the stator inductance of the motor, R s represents the stator resistance of the motor, ω represents the rotor speed, u γ (k) represents the actual voltage of the γ-axis at time k.

[0111] In a possible implementation manner, the calculation formula for the predicted current error is:

[0112]

[0113] Among them, Δi γ represents the predicted current error, represents the predicted γ-axis current at time k+1, i γ (k+1) represents the actual current of the γ-axis at time k+1.

[0114] In a possible implementation manner, the rotor position observer based on the predicted current model is specifically:

[0115]

[0116] in, represents the estimated rotor position, t represents time, Δi γ represents the predicted current error, represents the estimated rotor speed, n p represents the number of magnetic poles of the motor, J represents the moment of inertia of the motor, T e Represents the output torque of the motor, represents the load torque and disturbance, β1, β2 and β3 represent the gain coefficients of the observer.

[0117] The motor rapid starting system 20 based on the predicted current model provided by the present invention can execute the above-mentioned motor rapid starting method based on the predicted current model and achieve the same or similar technical effects. To avoid repetition, the present invention will not go into details.

[0118] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0119] (1) In the present invention, coordinate transformation is used to transform the three-phase current into a rotating coordinate system, and the actual current of the γ-axis and the actual current of the δ-axis in the rotating coordinate system are determined. According to the actual current of the γ-axis and the actual current of the δ-axis, the γ-axis current of the rotating coordinate system is predicted by using a predicted current model to obtain the predicted current of the γ-axis, and the predicted current of the γ-axis is calculated to be different from the actual current of the γ-axis to obtain the predicted current error. The γ-axis current of the rotating coordinate system is predicted by the predicted current model to improve the estimation accuracy of the rotor position. At the same time, the predicted current error is calculated to correct the position estimation, so that the rotor position estimation is more accurate, thereby improving the torque output capacity of the motor and improving the starting acceleration.

[0120] (2) In the present invention, a rotor position observer based on a predicted current model is constructed, the predicted current error is input into the rotor position observer, the estimated rotor position and speed are determined, and the estimated rotor position and speed are respectively sent to the coordinate transformation and speed loop controller to perform speed closed-loop control. No additional algorithm switching strategy is required, thereby achieving unified control from starting to high-speed stage and meeting the performance requirements of the motor for rapid starting.

[0121] It should be understood that the processor in the embodiment of the present invention may be a central processing unit (CPU), and the processor may also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0122] It should also be understood that the memory in the embodiments of the present invention may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of random access memory (RAM) are available, such as static RAM (SRAM), dynamic random access memory (DRAM), synchronous DRAM (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

[0123] The above embodiments can be implemented in whole or in part by software, hardware (such as circuits), firmware or any other combination. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center by wired (such as infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (for example, a floppy disk, a hard disk, a tape), an optical medium (for example, a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0124] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0125] In the present invention, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0126] It should be understood that in various embodiments of the present invention, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0127] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0128] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described equipment, devices and units can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0129] In the several embodiments provided by the present invention, it should be understood that the disclosed devices, apparatuses and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0130] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0131] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0132] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0133] An embodiment of the present invention provides a computer-readable storage medium having a computer program stored thereon. When the program is executed by a processor, the method for quickly starting a motor based on a predicted current model as described in the method embodiment is implemented.

[0134] A computer-readable storage medium provided by the present invention can implement the steps and effects of the motor quick starting method based on the predicted current model of the above method embodiment. To avoid repetition, the present invention will not go into details.

[0135] The beneficial effects brought about by the technical solution provided by the embodiment of the present invention include at least:

[0136] (1) In the present invention, coordinate transformation is used to transform the three-phase current into a rotating coordinate system, and the actual current of the γ-axis and the actual current of the δ-axis in the rotating coordinate system are determined. According to the actual current of the γ-axis and the actual current of the δ-axis, the γ-axis current of the rotating coordinate system is predicted by using a predicted current model to obtain the predicted current of the γ-axis, and the predicted current of the γ-axis is calculated to be different from the actual current of the γ-axis to obtain the predicted current error. The γ-axis current of the rotating coordinate system is predicted by the predicted current model to improve the estimation accuracy of the rotor position. At the same time, the predicted current error is calculated to correct the position estimation, so that the rotor position estimation is more accurate, thereby improving the torque output capacity of the motor and improving the starting acceleration.

[0137] (2) In the present invention, a rotor position observer based on a predicted current model is constructed, the predicted current error is input into the rotor position observer, the estimated rotor position and speed are determined, and the estimated rotor position and speed are respectively sent to the coordinate transformation and speed loop controller to perform speed closed-loop control. No additional algorithm switching strategy is required, thereby achieving unified control from starting to high-speed stage and meeting the performance requirements of the motor for rapid starting.

[0138] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

[0139] There are a few points to note:

[0140] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention, and other structures may refer to the general design.

[0141] (2) For the sake of clarity, in the drawings used to describe the embodiments of the present invention, the thickness of the layers or regions is exaggerated or reduced, that is, these drawings are not drawn according to the actual scale. It is understood that when an element such as a layer, film, region or substrate is referred to as being "on" or "under" another element, the element may be "directly" "on" or "under" the other element or there may be intermediate elements.

[0142] (3) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to obtain new embodiments.

[0143] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A motor quick starting method based on a predictive current model, characterized in that: include: S1: Pre-position the rotor in a stationary state to determine the initial position of the rotor; S2: Control the motor to enter the starting state and collect three-phase current; S3: transforming the three-phase current into a rotating coordinate system through coordinate transformation, and determining an actual current of a γ-axis and an actual current of a δ-axis in the rotating coordinate system; S4: predicting the γ-axis current of the rotating coordinate system according to the γ-axis actual current and the δ-axis actual current using a predicted current model to obtain a γ-axis predicted current; S5: performing a difference calculation on the γ-axis predicted current and the γ-axis actual current to obtain a predicted current error; S6: Construct a rotor position observer based on the predictive current model; S7: inputting the predicted current error into the rotor position observer to determine the estimated rotor position and speed; S8: sending the estimated rotor position and speed to the coordinate transformation and speed loop controller respectively to perform speed closed-loop control; S9: Repeat S2 to S8 to achieve quick start of the motor based on the predicted current model.

2. The method for rapid motor starting based on a predictive current model according to claim 1, characterized in that: The S1 specifically includes: S101: in a stationary state, setting the rotor position to zero, the d-axis current to zero, and the q-axis current to a constant less than the rated current, and making the permanent magnet of the motor reach a position perpendicular to the horizontal axis of the two-phase stationary coordinate system through current closed-loop control for a first preset time; S102: In a stationary state, the rotor position is set to zero, the q-axis current is set to zero, and the d-axis current is set to a constant less than the rated current. Through a second set time current closed-loop control, the permanent magnet of the motor is made to coincide with the horizontal axis of the two-phase stationary coordinate system to determine the initial position of the rotor.

3. The motor quick starting method based on the prediction current model according to claim 1, characterized in that: The calculation formula of the coordinate transformation is: Among them, i a 、i b and i c Represents the three-phase current, i α represents the α-axis current, i β represents the β-axis current, i γ represents the γ-axis current, i δ represents the delta axis current, represents the estimated rotor position.

4. The method for rapid motor starting based on a predictive current model according to claim 1, characterized in that: The calculation formula of the γ-axis predicted current is: in, represents the predicted γ-axis current at time k+1, i γ (k) represents the actual current of the γ axis at time k, T s Represents the operation cycle of the algorithm, L s Represents the stator inductance of the motor, R s represents the stator resistance of the motor, ω represents the rotor speed, u γ (k) represents the actual voltage of the γ-axis at time k.

5. The motor quick starting method based on the prediction current model according to claim 1, characterized in that: The calculation formula of the predicted current error is: Among them, Δi γ represents the predicted current error, represents the predicted γ-axis current at time k+1, i γ (k+1) represents the actual current of the γ-axis at time k+1.

6. The method for rapid motor starting based on a predictive current model according to claim 1, characterized in that: The rotor position observer based on the predicted current model is specifically: in, represents the estimated rotor position, t represents time, Δi γ represents the predicted current error, represents the estimated rotor speed, n p represents the number of magnetic poles of the motor, J represents the moment of inertia of the motor, T e Represents the output torque of the motor, represents the load torque and disturbance, β1, β2 and β3 represent the gain coefficients of the observer.

7. A motor quick start system based on a predictive current model, characterized in that: include: A positioning module is used to pre-position the rotor in a stationary state and determine the initial position of the rotor; The acquisition module is used to control the motor to enter the starting state and collect the three-phase current; A transformation module, used for transforming the three-phase current into a rotating coordinate system through coordinate transformation, and determining an actual current of a γ-axis and an actual current of a δ-axis in the rotating coordinate system; A prediction module, used to predict the γ-axis current of the rotating coordinate system according to the γ-axis actual current and the δ-axis actual current by using a prediction current model to obtain a γ-axis predicted current; A calculation module, used for performing a difference calculation between the γ-axis predicted current and the γ-axis actual current to obtain a predicted current error; A building block for building a rotor position observer based on a predictive current model; An input module, configured to input the predicted current error into the rotor position observer to determine an estimated rotor position and speed; A control module, used for sending the estimated rotor position and speed to the coordinate transformation and speed loop controller respectively, to perform speed closed-loop control; The repeating module is used to repeat S2 to S8 to achieve a quick start of the motor based on a predictive current model.

8. The motor rapid starting system based on the prediction current model according to claim 7, characterized in that: The positioning module is specifically used for: In a stationary state, the rotor position is set to zero, the d-axis current is set to zero, and the q-axis current is set to a constant less than the rated current, and the permanent magnet of the motor is made to reach a position perpendicular to the horizontal axis of the two-phase stationary coordinate system through current closed-loop control for a first preset time; In the stationary state, the rotor position is set to zero, the q-axis current is zero, and the d-axis current is a constant less than the rated current. Through the second setting time current closed-loop control, the permanent magnet of the motor is made to coincide with the horizontal axis of the two-phase stationary coordinate system to determine the initial position of the rotor.

9. The motor rapid starting system based on the prediction current model according to claim 7, characterized in that: The calculation formula of the coordinate transformation is: Among them, i a 、i b and i c Represents the three-phase current, i α represents the α-axis current, i β represents the β-axis current, i γ represents the γ-axis current, i δ represents the delta axis current, represents the estimated rotor position.

10. The motor rapid starting system based on the prediction current model according to claim 7, characterized in that: The calculation formula of the γ-axis predicted current is: in, represents the predicted γ-axis current at time k+1, i γ (k) represents the actual current of the γ axis at time k, T s Represents the operation cycle of the algorithm, L s Represents the stator inductance of the motor, R s represents the stator resistance of the motor, ω represents the rotor speed, u γ (k) represents the actual voltage of the γ-axis at time k.

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