Control method, device, equipment and storage medium of permanent magnet synchronous motor

Abstract

The present application provides a control method, device, equipment and storage medium of a permanent magnet synchronous motor, the method comprising: determining the predicted speed value at the second moment according to the actual speed value at the first moment, the actual speed value at the second moment, and the q-axis current change value at the first moment; obtaining the speed prediction error at the first moment, and processing the predicted speed value at the second moment according to the speed prediction error at the first moment to obtain the processed predicted speed value at the second moment; determining the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information; controlling the drilling work of the permanent magnet synchronous motor according to the control current at the second moment. The method provided by the present application improves the control accuracy of the permanent magnet synchronous motor and improves the anti-disturbance performance of the permanent magnet synchronous motor.

Description

Technical Field

[0001] The present application relates to motor control technology, and in particular to a control method, device, equipment and storage medium for a permanent magnet synchronous motor. Background Art

[0002] In order to meet the needs of wells with complex structures, rotary steerable drilling technology is becoming increasingly important as a new type of drilling technology. The mechanism used to control the drilling trajectory in the rotary steerable drilling system is called a steering mechanism, which can provide the system with accurate azimuth and well inclination. The steering mechanism is driven by a motor to complete its work; only by accurately controlling the motor and then driving the steering mechanism can the steering mechanism work better, thereby providing accurate well inclination and azimuth for the rotary steerable drilling system.

[0003] In the prior art, a permanent magnet synchronous motor can be used to drive the guide mechanism, and a proportional integral (PI) controller can be used in the permanent magnet synchronous motor to output a control current, thereby controlling the permanent magnet synchronous motor to complete the work.

[0004] However, in the prior art, based on the way in which the PI controller outputs control current, as the environment of the permanent magnet synchronous motor changes, environmental factors will affect the parameters of the permanent magnet synchronous motor, and these parameters will in turn affect the control current output by the PI controller; thereby causing the output control current to be inaccurate, making it impossible to accurately control the permanent magnet synchronous motor to complete the work, and further, the rotary steerable drilling system is unable to accurately complete the drilling work. Summary of the invention

[0005] The present application provides a control method, device, equipment and storage medium for a permanent magnet synchronous motor, which are used to solve the problems of low control accuracy, slow response speed and poor anti-disturbance of the permanent magnet synchronous motor in the prior art.

[0006] In a first aspect, the present application provides a control method for a permanent magnet synchronous motor, the method being applied to a permanent magnet synchronous motor, the method comprising:

[0007] Determine the predicted speed value at the second moment according to the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment, wherein the second moment is a moment after the first moment, and the third moment is a moment before the first moment;

[0008] Obtaining a speed prediction error at the first moment, and processing a predicted speed value at the second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment;

[0009] determining the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information, wherein the reference trajectory information is used to characterize the change process of the speed;

[0010] The drilling operation of the permanent magnet synchronous motor is controlled according to the control current at the second moment.

[0011] Optionally, determining the predicted speed value at the second moment according to the actual speed value at the first moment, the actual speed value at the second moment, and the q-axis current change value at the first moment includes:

[0012] Based on a preset permanent magnet motor mechanical motion relationship, a Z-domain transfer function is determined, wherein the Z-domain transfer function is used to determine a relationship between a rotational speed and a q-axis current change value;

[0013] Determining the relationship between the actual rotation speed value and the q-axis current change value according to the Z-domain transfer function;

[0014] Based on the relationship between the actual speed value and the q-axis current change value, the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment are processed to obtain the predicted speed value at the second moment, wherein the q-axis current change value at the first moment is the difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment.

[0015] Optionally, before determining the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information, the method further includes:

[0016] The reference trajectory information is established according to the reference speed value and the actual speed value at the first moment.

[0017] Optionally, determining the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information includes:

[0018] Determine the q-axis current error value at the second moment according to the processed predicted speed value at the second moment, the reference trajectory information, and the q-axis current change value at the first moment, wherein the q-axis current change value at the first moment is the difference between the q-axis current actual value at the first moment and the q-axis current actual value at a third moment, and the third moment is located before the first moment;

[0019] The control current at the second moment is obtained according to the q-axis current error value at the second moment and the q-axis current actual value at the first moment.

[0020] Optionally, controlling the drilling operation of the permanent magnet synchronous motor according to the control current at the second moment includes:

[0021] Acquire an actual rotation speed value at a first moment and a current reference value at the first moment, and determine a current compensation value at the second moment;

[0022] Compensating the control current at the second moment according to the current compensation value at the second moment to obtain a compensated control current at the second moment;

[0023] The drilling operation of the permanent magnet synchronous motor is controlled according to the compensated control current at the second moment.

[0024] Optionally, the compensated control current at the second moment includes a d-axis current reference value at the second moment and a q-axis current reference value at the second moment;

[0025] Controlling the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment includes:

[0026] Acquire the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, and motor state information;

[0027] According to a preset current preset model, wherein the current preset model represents the relationship between current and voltage, determine a voltage preset model;

[0028] Based on the voltage preset model, the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, the d-axis current reference value at the second moment, the q-axis current reference value at the second moment and the motor status information are processed to obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

[0029] Optionally, after obtaining the d-axis voltage at the second moment and the q-axis voltage at the second moment, the method further includes:

[0030] The d-axis voltage at the second moment is corrected to obtain a corrected d-axis voltage at the second moment, and the q-axis voltage at the second moment is corrected to obtain a corrected q-axis voltage at the second moment.

[0031] Optionally, correcting the d-axis voltage at the second moment to obtain a corrected d-axis voltage at the second moment includes:

[0032] Acquire a d-axis current reference value at the first moment, and perform integration processing on the d-axis current reference value at the first moment to obtain a first intermediate value;

[0033] The d-axis voltage at the second moment is corrected according to the first intermediate value to obtain a corrected d-axis voltage at the second moment.

[0034] Optionally, correcting the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment includes:

[0035] Acquire a q-axis current reference value at the first moment, and integrate the q-axis current reference value at the first moment to obtain a second intermediate value;

[0036] The flux linkage value of the permanent magnet synchronous motor is compensated according to the second intermediate value to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

[0037] Optionally, the motor state information includes: an actual speed value of the permanent magnet synchronous motor, a resistance of the permanent magnet synchronous motor, an inductance of the permanent magnet synchronous motor, and a flux linkage value of the permanent magnet synchronous motor.

[0038] In a second aspect, the present application provides a permanent magnet synchronous motor control device, the device comprising:

[0039] a first determining unit, configured to determine a predicted speed value at a second moment according to an actual speed value at a first moment, an actual speed value at a third moment, and a q-axis current change value at the first moment, wherein the second moment is a moment after the first moment, and the third moment is a moment before the first moment;

[0040] an acquisition unit, configured to acquire a speed prediction error at the first moment, and process the predicted speed value at the second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment;

[0041] a second determining unit, configured to determine the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information, wherein the reference trajectory information is used to characterize a change process of the speed;

[0042] A control unit is used to control the drilling operation of the permanent magnet synchronous motor according to the control current at the second moment.

[0043] Optionally, the first determining unit includes:

[0044] A first determination module is used to determine a Z-domain transfer function based on a preset permanent magnet motor mechanical motion relationship, wherein the Z-domain transfer function is used to determine a relationship between a rotation speed and a q-axis current change value;

[0045] A second determination module is used to determine the relationship between the actual rotation speed value and the q-axis current change value according to the Z-domain transfer function;

[0046] The third determination module is used to process the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment based on the relationship between the actual speed value and the q-axis current change value, so as to obtain the predicted speed value at the second moment, wherein the q-axis current change value at the first moment is the difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment.

[0047] Optionally, the device comprises:

[0048] An establishing unit is used to establish the reference trajectory information according to the reference speed value and the actual speed value at the first moment before the second determining unit determines the control current at the second moment according to the processed predicted speed value and the preset reference trajectory information at the second moment.

[0049] Optional, including:

[0050] a fourth determination module, configured to determine a q-axis current error value at the second moment according to the processed predicted speed value at the second moment, the reference trajectory information, and the q-axis current change value at the first moment, wherein the q-axis current change value at the first moment is a difference between an actual value of the q-axis current at the first moment and an actual value of the q-axis current at a third moment, and the third moment is located before the first moment;

[0051] The fifth determination module is used to obtain the control current at the second moment according to the q-axis current error value at the second moment and the actual value of the q-axis current at the first moment.

[0052] Optionally, the control unit includes:

[0053] An acquisition module, used to acquire an actual rotation speed value at a first moment and a current reference value at the first moment, and determine a current compensation value at the second moment;

[0054] a sixth determining module, configured to compensate the control current at the second moment according to the current compensation value at the second moment to obtain the compensated control current at the second moment;

[0055] A control module is used to control the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment.

[0056] Optionally, the compensated control current at the second moment includes a d-axis current reference value at the second moment and a q-axis current reference value at the second moment; and the control module includes:

[0057] An acquisition submodule, used to acquire the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, and motor state information;

[0058] A first determination submodule is used to determine a voltage preset model according to a preset current preset model, wherein the current preset model represents the relationship between current and voltage;

[0059] The second determination submodule is used to process the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, the d-axis current reference value at the second moment, the q-axis current reference value at the second moment and the motor state information based on the voltage preset model to obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

[0060] Optionally, the control module includes:

[0061] a first correction submodule, configured to correct the d-axis voltage at the second moment after the second determination submodule obtains the d-axis voltage at the second moment and the q-axis voltage at the second moment, so as to obtain a corrected d-axis voltage at the second moment;

[0062] The second correction submodule is used to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

[0063] Optionally, the first correction submodule is specifically used to:

[0064] Acquire a d-axis current reference value at the first moment, and perform integration processing on the d-axis current reference value at the first moment to obtain a first intermediate value;

[0065] The d-axis voltage at the second moment is corrected according to the first intermediate value to obtain a corrected d-axis voltage at the second moment.

[0066] Optionally, the second correction submodule is specifically used for:

[0067] Acquire a q-axis current reference value at the first moment, and integrate the q-axis current reference value at the first moment to obtain a second intermediate value;

[0068] The flux linkage value of the permanent magnet synchronous motor is compensated according to the second intermediate value to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

[0069] Optionally, the motor state information includes: an actual speed value of the permanent magnet synchronous motor, a resistance of the permanent magnet synchronous motor, an inductance of the permanent magnet synchronous motor, and a flux linkage value of the permanent magnet synchronous motor.

[0070] In a third aspect, the present application provides an electronic device, which is applied to a permanent magnet synchronous motor, and includes: a memory, a processor;

[0071] A memory for storing instructions executable by the processor;

[0072] The processor is used to execute the method as described in any one of the first aspects according to the executable instructions.

[0073] In a fourth aspect, the present application provides a permanent magnet synchronous motor, which includes the electronic device as described in the third aspect.

[0074] In a fifth aspect, the present application provides a rotary steerable drilling system, which includes a permanent magnet synchronous motor and a steering mechanism as described in the third aspect, wherein the steering mechanism is connected to the permanent magnet synchronous motor.

[0075] In a sixth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, they are used to implement the method as described in any one of the first aspects.

[0076] In a seventh aspect, the present application provides a computer program product, comprising a computer program, which, when executed by a processor, implements the method as described in any one of the first aspects.

[0077] The control method, device, equipment and storage medium of the permanent magnet synchronous motor provided by the present application determine the predicted speed value at the second moment according to the actual speed value at the first moment, the actual speed value at the second moment, and the q-axis current change value at the first moment, wherein the second moment is a moment after the first moment; obtain the speed prediction error at the first moment, and process the predicted speed value at the second moment according to the speed prediction error at the first moment to obtain the processed predicted speed value at the second moment; determine the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information, wherein the reference trajectory information is used to characterize the change process of the speed; control the drilling work of the permanent magnet synchronous motor according to the control current at the second moment. The method provided by the present application improves the control accuracy of the permanent magnet synchronous motor and improves the anti-disturbance performance of the permanent magnet synchronous motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0079] Figure 1This is the block diagram of the dual-loop PI control algorithm for permanent magnet synchronous motor;

[0080] Figure 2 It is the block diagram of the dual-loop speed PI control and current deadbeat predictive control algorithm of permanent magnet synchronous motor;

[0081] Figure 3 A flow chart of a control method for a permanent magnet synchronous motor provided in an embodiment of the present application;

[0082] Figure 4 A flow chart of another control method for a permanent magnet synchronous motor provided in an embodiment of the present application;

[0083] Figure 5 This is the schematic diagram of predictive control;

[0084] Figure 6 This is a comparison chart of control strategies based on prediction models;

[0085] Figure 7 It is a schematic diagram of feedback correction;

[0086] Figure 8 It is a speed loop predictive controller for permanent magnet synchronous motor;

[0087] Fig. 9 This is the block diagram of the extended state observer system;

[0088] Fig.10 It is a speed loop predictive controller based on extended state observer;

[0089] Fig.11 A schematic diagram of deadbeat current prediction control provided in an embodiment of the present application;

[0090] Fig.12 The permanent magnet synchronous motor control system provided for this application;

[0091] Fig.13 This is a comparison chart of speed response simulation under different control methods;

[0092] Fig.14 This is the simulation diagram of the q-axis current response without the static error elimination algorithm;

[0093] Fig.15 The simulation diagram of q-axis current response under the static error elimination algorithm is added;

[0094] Fig.16 A schematic diagram of the structure of a permanent magnet synchronous motor control device provided in an embodiment of the present application;

[0095] Fig.17 A schematic diagram of the structure of another permanent magnet synchronous motor control device provided in an embodiment of the present application;

[0096] Fig.18 A block diagram of an electronic device provided in an embodiment of the present application.

[0097] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0098] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0099] The specific application scenario of this application is the rotary steerable drilling system. The rotary steerable drilling technology is a new type of drilling technology. It has a stronger ability to control the wellbore trajectory, greatly improves the quality of the wellbore trajectory, and meets the needs of drilling complex wells. At the same time, the rotary steerable drilling system requires the motor speed to respond quickly and have high steady-state accuracy. The mechanism used to control the drilling trajectory in the rotary steerable drilling system is called a steering mechanism, which consists of a stable platform and a double eccentric ring. The steering mechanism can provide the drilling system with precise azimuth and well inclination. The steering mechanism is driven by a motor to complete its work. Only by accurately controlling the motor can the steering mechanism work better, thereby providing the drilling system with precise azimuth and well inclination.

[0100] In one example, a permanent magnet synchronous motor can be used to drive the guide mechanism. The current control algorithms used for permanent magnet synchronous motor control mainly include vector control algorithm and direct torque control algorithm. The two control strategies have little difference in motor response speed. Vector control response is smoother, while direct torque control has obvious torque and flux pulsation. Therefore, vector control is often used as the control strategy for permanent magnet synchronous motors.

[0101] Figure 1 Figure 1 is a block diagram of the dual-loop PI control algorithm for a permanent magnet synchronous motor. Figure 1As shown in the figure, the permanent magnet synchronous motor vector control system is a dual-loop control system consisting of a speed loop and a current loop. Both the speed loop and the current loop controllers use PI controllers. PI control is a common current loop controller. In the actual operation of the motor, due to the influence of temperature and environmental changes, it is difficult to avoid changes in parameters such as resistance and inductance in the motor armature circuit. At this time, the PI control parameters must be adjusted accordingly, but the PI controller will not automatically adjust the parameters in real time, and the motor current can no longer strictly follow its given changes, resulting in a decrease in system stability. In addition, the way the PI controller improves the dynamic response of the system is to increase the controller gain, but this will bring about overshoot and noise problems, making it difficult to balance the contradiction between the rapidity of the system response and stability. However, due to the above-mentioned defects of the traditional PI controller, PI control cannot well adapt to the high requirements of the drilling trajectory robot system for speed control.

[0102] Figure 2 The figure is a block diagram of the dual-loop speed PI control and current deadbeat predictive control algorithm for permanent magnet synchronous motors. Figure 2 As shown in the figure, the speed loop of the permanent magnet synchronous motor vector control system is PI control, and the current loop is current deadbeat predictive control. Compared with traditional vector control, predictive control can obtain higher dynamic response performance and smaller current harmonic components. After the current loop uses deadbeat predictive control, the current loop current following speed is improved, and the speed control accuracy of the speed loop is also improved to a certain extent. However, since the speed loop uses a PI controller and due to the defects of PI control, there is still room for improvement in the speed control accuracy. Figure 2 The control scheme shown also does not improve the anti-disturbance performance of the system, does not improve the motor parameter error situation, and cannot meet the requirements of the drilling system for anti-disturbance and avoiding parameter errors.

[0103] The control method, device, equipment and storage medium of the permanent magnet synchronous motor provided in the present application are intended to solve the above technical problems in the prior art.

[0104] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0105] Figure 3 A flow chart of a control method for a permanent magnet synchronous motor provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, the method includes:

[0106] 101. Determine a predicted speed value at a second moment according to an actual speed value at a first moment, an actual speed value at a third moment, and a q-axis current change value at the first moment, wherein the second moment is a moment after the first moment and the third moment is a moment before the first moment.

[0107] Exemplarily, the execution subject of this embodiment may be a computer or a background control system. This embodiment is described with a computer as the execution subject.

[0108] In one example, the motor speed can be obtained through a speed sensor, and the working current of the motor can be sampled. The q-axis current value can be obtained through Clarke transformation and Park transformation, and then the q-axis current change value at a certain moment can be determined. Clarke transformation is to transform each physical quantity based on the 3-axis, 2-dimensional stator stationary coordinate system into the 2-axis stator stationary coordinate system, and Park transformation transforms the stator current vector based on the αβ2-axis orthogonal coordinate system into a 2-axis system that rotates synchronously with the rotor flux. Since the speed of the motor is related to its control current, the speed at the second moment can be predicted based on the actual speed values ​​at the first moment and the third moment, and the q-axis current change value at the first moment, where the second moment is the moment after the first moment and the third moment is the moment before the first moment.

[0109] 102. Obtain a speed prediction error at a first moment, and process a predicted speed value at a second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment.

[0110] Exemplarily, the actual speed at the first moment and the predicted speed value at the first moment are first obtained, the speed prediction error at the first moment is obtained according to the actual speed at the first moment and the predicted speed value at the first moment, and the predicted speed value at the second moment is corrected according to the speed prediction error at the first moment to obtain the processed predicted speed value at the second moment. Feedback correction can reduce the error of the system and enhance the robustness of the predictive control system.

[0111] 103. Determine the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information, wherein the reference trajectory information is used to characterize a change process of the speed.

[0112] For example, in order to make the actual speed smoothly approach the reference speed, reference trajectory information is introduced to characterize the speed change process, and the reference trajectory information can be determined according to the reference speed and the actual speed. The change value of the q-axis current can be determined according to the processed predicted speed value at the second moment and the preset reference trajectory information, and then the control current at the second moment can be determined.

[0113] 104. According to the control current at the second moment, the drilling operation of the permanent magnet synchronous motor is controlled.

[0114] For example, a current prediction model of the motor can be obtained according to the current state equation of the motor, and the current prediction model represents the relationship between the actual current value at the first moment and the current reference value at the second moment (the control current at the second moment) and the control voltage. The control voltage vector of the permanent magnet synchronous motor can be determined according to the control current at the second moment, the actual current value at the first moment, and the current prediction model, and then the drilling operation of the permanent magnet synchronous motor can be controlled according to the control voltage vector.

[0115] In this embodiment, the predicted speed value at the second moment is determined based on the actual speed value at the first moment, the actual speed value at the second moment, and the q-axis current change value at the first moment; the speed prediction error at the first moment is obtained, and the predicted speed value at the second moment is processed according to the speed prediction error at the first moment to obtain the processed predicted speed value at the second moment; according to the processed predicted speed value at the second moment and the preset reference trajectory information, the control current at the second moment is determined, and according to the control current at the second moment, the drilling work of the permanent magnet synchronous motor is controlled. The method provided in this embodiment can improve the control accuracy of the permanent magnet synchronous motor and improve the response speed.

[0116] Figure 4 A flow chart of another control method of a permanent magnet synchronous motor provided in an embodiment of the present application is as follows: Figure 4 As shown, the method includes:

[0117] 201. Based on the preset mechanical motion relationship of the permanent magnet motor, determine the Z-domain transfer function, which is used to determine the relationship between the rotational speed and the q-axis current change value; according to the Z-domain transfer function, determine the relationship between the actual rotational speed value and the q-axis current change value.

[0118] Exemplarily, the execution subject of this embodiment may be a computer or a background control system. This embodiment is described with a computer as the execution subject.

[0119] In one example, Figure 5 is the predictive control principle diagram, Figure 6 This is a comparison chart of control strategies based on prediction models. Figure 5 As shown in the figure, predictive control includes three parts: predictive model, rolling optimization, and feedback correction. A predictive model is a model that can describe the future dynamics of a system. Transfer functions, state equations, step responses of linear stable objects, pulse responses, etc. can all be used as predictive models. Based on the predictive model's ability to describe the future dynamic behavior of the system, different control strategies can be implemented to obtain the corresponding system output. By measuring its performance indicators, a better control strategy can be selected to achieve optimal control. Figure 6 As shown, 1 and 2 are control sequences, 3 and 4 are output trajectories under control strategies 1 and 2 respectively. The control strategy can be selected by comparing the output trajectories.

[0120] In one example, based on a preset mechanical motion relationship of a permanent magnet motor, a Z-domain transfer function is determined, and the Z-domain transfer function is used to determine the relationship between the rotation speed and the change value of the q-axis current. Specifically, in i d =0, the mechanical motion equation of the permanent magnet synchronous motor is:

[0121]

[0122] Among them, ω r is the motor speed, T L is the load torque, J is the moment of inertia, T e is the electromagnetic inertia, and B is the damping coefficient.

[0123] Since the prediction model uses the nominal model of the motor, the load disturbance T can be ignored. L The influence of , converting equation (3.1) to the frequency domain can obtain equation (3.2), and then discretizing it

[52] The Z-domain transfer function is obtained as follows (3.3):

[0124]

[0125]

[0126] Where T is the sampling period, K m =1.5n p ψ f , K m is the torque constant, n p is the pole pair number, ψ f It is the flux linkage generated by the permanent magnet of the motor.

[0127] From the transfer function, the actual speed output at time kT and time (k+1)T is:

[0128] ω r (k) = a0i q (k-1)-b0ω r (k-1) (3.4)

[0129] ω r (k+1)=a0i q (k)-b0ω r (k) (3.5)

[0130] The relationship between the actual speed value and the q-axis current change value can be obtained from equations (3.4) and (3.5).

[0131] 202. Based on the relationship between the actual speed value and the q-axis current change value, the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment are processed to obtain the predicted speed value at the second moment, wherein the q-axis current change value at the first moment is the difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment, the third moment is before the first moment, and the second moment is after the first moment.

[0132] For example, based on the relationship between the actual speed value and the q-axis current change value obtained in step 201, the predicted speed value at the next moment can be determined according to the actual speed value and the q-axis current change value. Specifically, according to equations (3.5) and (3.4) in step 201, equation (3.6) can be obtained. Note that q (k)-i q (k-1) is the q-axis current increment at time kT The predicted speed output at time (k+1)T can be obtained:

[0133]

[0134] Among them, kT is the first moment, (k+1)T is the second moment, and (k-1)T is the third moment. is the difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment.

[0135] 203. Obtain a speed prediction error at a first moment, and process a predicted speed value at a second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment.

[0136] For example, in actual industrial production applications, the mismatch of the prediction model and various external disturbances will cause system output errors, resulting in system oscillations and a decrease in steady-state accuracy. Therefore, feedback correction is required to provide feedback on the system output error. Figure 7 is a schematic diagram of feedback correction, such as Figure 7 In the feedback correction shown, curve 1 is the predicted state at time k, point Y is the actual state value at time k+1, line segment ΔY is the error between the actual state value at time k+1 and the predicted state value, and the curve 2 on the right side of time k+1 is the predicted output of the system after feedback correction.

[0137] In one example, the actual speed at the first moment and the predicted speed value at the first moment are first obtained, and the speed prediction error at the first moment is obtained according to the actual speed at the first moment and the predicted speed value at the first moment. The predicted speed value at the second moment is corrected according to the speed prediction error at the first moment to obtain the processed predicted speed value at the second moment, and the error is recorded as e(k)=ω r (k)-ω rm (k), then the predicted speed value after processing at the second moment is:

[0138] ω rp (k+1)=ω rm (k+1)+e(k) (3.7)

[0139] 204. Establish reference trajectory information according to the reference speed value and the actual speed value at the first moment, wherein the reference trajectory information is used to characterize a change process of the speed.

[0140] For example, in order to make the actual speed smoothly approach the reference speed, the reference trajectory information is introduced to characterize the process of speed change. In this step, an exponential smoothing reference trajectory is designed so that ω r (k) Smoothly tends to ω ref (k), where ω ref (k) is the reference speed, ω r (k) is the actual speed, and the reference trajectory information is as shown in formula 3.8:

[0141] y r (k+1)=αω r (k)+(1-α)ω ref (k) (3.8)

[0142] 205. Determine the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information.

[0143] In one example, step 205 specifically includes: determining the q-axis current error value at the second moment based on the processed predicted speed value at the second moment, the reference trajectory information, and the q-axis current change value at the first moment, wherein the q-axis current change value at the first moment is the difference between the q-axis current actual value at the first moment and the q-axis current actual value at the third moment, and the third moment is before the first moment; obtaining the control current at the second moment based on the q-axis current error value at the second moment and the q-axis current actual value at the first moment.

[0144] For example, in order to make the processed predicted speed value ω at the second moment rp (k+1), and the designed speed reference trajectory y rThe error between (k+1) is as close to 0 as possible, and its weighting parameter is set to λ. At the same time, the q-axis current error is as close to 0 as possible, and its weighting parameter is set to β. The quadratic performance index is designed as follows:

[0145]

[0146] For quadratic performance index J P and q-axis current error By finding the partial derivative to be 0, we can get the optimal current control error of the q-axis at time kT. As shown in equation (3.10), the q-axis reference current As shown in formula (3.11).

[0147]

[0148]

[0149] Figure 8 For the permanent magnet synchronous motor speed loop prediction controller, steps 201 to 205 can be summarized as follows: Figure 8 In the system shown in FIG. 1 , the system inputs the speed reference value and the actual speed value at time kT to obtain the system reference trajectory at time (k+1)T, and obtains the system closed-loop predicted output at time (k+1)T through the prediction model and feedback correction. The quadratic optimal performance index of the reference trajectory and the predicted output is optimized to obtain the system control output, thereby achieving optimal control of the system.

[0150] In one example, step 206 specifically includes: obtaining an actual rotational speed value at a first moment and a current reference value at the first moment, and determining a current compensation value at a second moment; compensating the control current at the second moment according to the current compensation value at the second moment to obtain the compensated control current at the second moment, and controlling the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment.

[0151] For example, since the prediction model of the prediction controller used in the speed loop of the permanent magnet synchronous motor control system is based on the nominal model of the system, the influence of the load torque and the unmodeled dynamics is not considered, and the external torque disturbance will affect the steady-state accuracy of the control system, the feedforward compensation of the load torque in the speed loop can improve the anti-disturbance performance of the permanent magnet synchronous motor control system. In this step, the extended state observer method is used to obtain the load torque.

[0152] Active disturbance rejection control is a control algorithm that excels in anti-disturbance performance. Its core is the extended state observer (ESO) that can observe system disturbances. The extended state observer records the uncertainty of the system model itself as internal disturbances and external disturbances as external disturbances. The system disturbance composed of the two can be estimated by the extended observer. Fig. 9 is the block diagram of the extended state observer system, as Fig. 9 As shown in the figure, in an n-order system, v is the reference input of the control object. The system output y and its derivatives of each order are observed by the extended state observer, and the output z1...z n The uncertainty of the system model itself is recorded as the internal disturbance of the system, and the external disturbance is recorded as the external disturbance of the system. The system disturbance composed of the two can be estimated by the extended observer, and the output z n+1 The error between the reference input and the output of the extended state observer is used as the input of the control system, and the detected system disturbance z n+1 Compensate for the control effect of the control system.

[0153] Set the system function as shown in formula 3.12:

[0154]

[0155] In the formula, is an unknown function, x(t) is the system state quantity, which is measurable, u(t) is the system control quantity, and b is the control gain.

[0156] For equation 3.12, replace x (n) (t) is expanded into the state variables to obtain the expanded state variable group x(t), ..., x (n-1) (t), x (n) (t), from which the nonlinear system can be constructed as shown in Equation 3.13:

[0157]

[0158] Use each state of the system to track the expanded state change x(t), ..., x (n-1) (t), x (n) (t), then we have formula 3.14:

[0159]

[0160] The following is an analysis of the solution that satisfies equation 3.14. Here, equation 3.15 is written as follows:

[0161]

[0162] Where α(t) is the disturbance during the operation of the system. If we can select a suitable nonlinear function group g1(z),...,g n (z), g n+1 (z), its real-time value can be estimated without knowing the function and variable form of α(t).

[0163] g1(z),...,g n (z), g n+1 The choice of (z) also determines the solution of equation 3.15. We take the difference between each state of equation 3.14 and equation 3.15, and record it as equation 3.16:

[0164]

[0165] We can get formula 3.17:

[0166]

[0167] In equation 3.17, ω(t) is an unknown external disturbance. For ω(t) that varies arbitrarily within a certain range, an appropriate function group g1(z),...,g n (z), g n+1 (z), so that the system of equation 3.17 above is stable about the origin, so that each state of equation 3.13 can track each expanded state in equation 3.15. Equation 3.13 is called the extended state observer (ESO) of system 3.12. It has nothing to do with the system equation, but only with the rate of change of the real-time value α(t) of the system disturbance term. Therefore, ESO is more robust.

[0168] In one example, Fig.10 is a speed loop predictive controller based on an extended state observer, such as Fig.10 As shown in the figure, the output of the extended state observer is fed forward to the control output of the permanent magnet synchronous motor speed loop predictive control to perform disturbance compensation to improve the system's anti-disturbance capability. In the surface-mounted permanent magnet synchronous motor, the inductance of the AC and DC axes is equal, that is, L d =L q , the speed output equation is:

[0169]

[0170] In formula 3.18, is the comprehensive disturbance term, and the parameter term u=i q .

[0171] Since the speed loop of the permanent magnet synchronous motor is a first-order model, the designed extended state observer is also first-order, as shown in Equation 3.19, where u is the reference value of the quadrature axis current ω is the actual speed, β21 , β 22 Set parameters for the observer.

[0172]

[0173] It can be obtained from formula 3.22 that the total disturbance in the permanent magnet synchronous motor system can be determined according to the actual speed value at the first moment and the q-axis current reference value at the first moment, and the current compensation value at the second moment can be determined according to the total disturbance; then, the control current at the second moment is compensated according to the current compensation value at the second moment to obtain the compensated control current at the second moment, and the drilling work of the permanent magnet synchronous motor is controlled according to the compensated control current at the second moment.

[0174] Step 205 is the process of establishing an extended state observer, which is used to observe the defects of predictive control in anti-disturbance. The system disturbance is observed and feedforwarded by the extended state observer to improve the anti-disturbance capability of the system.

[0175] 207. Control the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment.

[0176] For example, the current loop serves as the inner loop of the system, and its current following performance is the key to system control. Using a predictive controller as the current loop controller can improve the current loop bandwidth and achieve better dynamic and static performance of current control. Since the current ripple of the zero-beat current prediction is small, the steady-state accuracy is high, and the dynamic response is fast, it can achieve better current following than the PI controller. Therefore, this embodiment adopts the zero-beat current predictive control as the current loop controller of the system. Fig.11 A schematic diagram of deadbeat current prediction control provided in an embodiment of the present application is shown in FIG. Fig.11 As shown, this embodiment adopts deadbeat current prediction control as the current loop controller of the system, and the control voltage of the permanent magnet synchronous motor can be determined according to the actual current value and the current reference value.

[0177] In one example, the compensated control current at the second moment includes a d-axis current reference value at the second moment and a q-axis current reference value at the second moment.

[0178] Step 207 specifically includes the following steps:

[0179] The first step is to obtain the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, and the motor state information, wherein the motor state information includes: the actual speed value of the permanent magnet synchronous motor, the resistance of the permanent magnet synchronous motor, the inductance of the permanent magnet synchronous motor, and the flux value of the permanent magnet synchronous motor.

[0180] The second step is to determine a voltage preset model according to a preset current preset model, wherein the current preset model represents the relationship between current and voltage.

[0181] Specifically, the permanent magnet synchronous motor current prediction model is shown in the following formula (3.20):

[0182] i(k+1)=F(k)×i(k)+G=u(k)+H(k) (3.20)

[0183] In equation 3.20: i(k)=[i d (k) i q (k)] T ; u(k)=[u d (k) u q (k)] T .

[0184]

[0185] It can be seen from formula 3.23 that the voltage preset model can be determined according to the actual value of the d-axis current at the first moment obtained in the first step, the actual value of the q-axis current at the first moment and the motor state information, wherein the motor state information is the parameters of the permanent magnet synchronous motor, including: the actual speed value of the permanent magnet synchronous motor, the resistance of the permanent magnet synchronous motor, the inductance of the permanent magnet synchronous motor, and the magnetic flux value of the permanent magnet synchronous motor.

[0186] The voltage preset model for the deadbeat current prediction control calculation is shown in Equation 3.21:

[0187] u(k)=G -1 [x * (k+1)-F(k)x(k)-H(k)] (3.21)

[0188] The third step is to process the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, the d-axis current reference value at the second moment, the q-axis current reference value at the second moment and the motor status information based on the voltage preset model to obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

[0189] Exemplarily, according to the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment and the motor status information, as well as the d-axis current reference value at the second moment and the q-axis current reference value at the second moment obtained in the first step, substituting them into the voltage preset model obtained in the second step can obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

[0190] The fourth step is to correct the d-axis voltage at the second moment to obtain a corrected d-axis voltage at the second moment.

[0191] In one example, the fourth step specifically includes: obtaining a d-axis current reference value at a first moment, integrating the d-axis current reference value at the first moment to obtain a first intermediate value; and correcting the d-axis voltage at a second moment according to the first intermediate value to obtain a corrected d-axis voltage at the second moment.

[0192] For example, as the motor runs, the actual parameters of the motor will change, and there will be errors with the parameters in the prediction model, which will affect the control performance. Therefore, it is necessary to correct the d-axis voltage at the second moment and the q-axis voltage at the second moment obtained in the third step.

[0193] The parameters involved in the preset model mainly include resistance R, inductance L and flux linkage ψ f . Due to the value of the motor resistance and inductance, the resistance part 1-TR<<1, the parameter error of the resistance has little effect on the overall calculation, and is not analyzed here. Approximate 1-TR<<1 to 1, and simplify the above equations (3.20) and (3.21):

[0194] x(k+1)=I(k)x(k)+Gu(k)+H(k) (3.22)

[0195] u(k)=G -1 [x * (k+1)-I(k)x(k)-H(k)] (3.23)

[0196] In the formula

[0197] In the above formula (3.23), u(k) is the control voltage vector at time kT. By applying it to the actual motor model at the next time (k+1)T, the actual current shown in the following formula (3.24) can be obtained.

[0198] x(k+1)=I(k)x(k)+G0u(k)+H0(k) (3.24)

[0199] In formula 3.24: L0, ψf0 represent the actual motor inductance and flux parameters respectively.

[0200] Substituting u(k) into x(k+1), we can obtain the relationship between the current response and the current setting when there is an error between the prediction model parameters of the current prediction control and the actual current:

[0201]

[0202]

[0203] Among them, ΔL and Δψ fare the differences between the controller motor model parameters and the actual motor parameters, ΔL=L-L0, Δψ f =ψ f -ψ f0 .

[0204] From equations 3.25 and 3.26, we can determine i d The change of (k+1) mainly depends on the variable ΔL. d =0 control strategy, that is, the d-axis reference current i d * (k+1)=0, so equation 3.25 can be rewritten as equation 3.27:

[0205]

[0206] According to formula 3.27, it can be determined that the d-axis current static error is in direct proportion to the inductance error ΔL. If the d-axis current static error is eliminated, the influence of the inductance error on the d-axis current needs to be eliminated. Therefore, in this embodiment, the d-axis current static error is first integrated to obtain formula 3.28:

[0207]

[0208] In formula 3.28, K id is the integral compensation coefficient, It is the d-axis voltage control after adding the d-axis current static difference processing. is the corrected d-axis voltage at the second moment.

[0209] The fifth step is to correct the q-axis voltage at the second moment to obtain the corrected q-axis voltage at the second moment.

[0210] In one example, the fifth step specifically includes: obtaining a q-axis current reference value at a first moment, integrating the q-axis current reference value at the first moment to obtain a second intermediate value; compensating the magnetic flux value of the permanent magnet synchronous motor according to the second intermediate value to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

[0211] For example, it is assumed that the actual current of the q axis does not change much and is approximately equal within an interval of 1, that is, i q (k) = i q (k+1), then the equation 3.26 in the fourth step can be rewritten as equation 3.29:

[0212]

[0213] According to formula 3.29, the q-axis current static difference Δi can be determined qThe size of (k+1) is determined by two parts. The first part is related to the inductance error ΔL and the d-axis current i d (k) is directly proportional to the flux error Δψ. f In direct proportion.

[0214] First, the first part of the q-axis current static difference in equation 3.29 is analyzed. Ignoring the influence of flux error on the q-axis current static difference, equation 3.29 can be written as equation 3.30:

[0215]

[0216] After simplification, the first part of the q-axis current static difference is directly proportional to the inductance error ΔL and directly proportional to the d-axis current static difference. After the fourth step, the d-axis current static difference has been eliminated, so the first part of the q-axis current static difference is also eliminated.

[0217] Analyzing the second part of the q-axis current static difference in equation (3.29), equation 3.29 can be transformed into equation 3.31:

[0218]

[0219] The simplified second part of the q-axis current static error and the flux error Δψ f is in direct proportion to the flux error Δψ. f It is only related to the static error of the q-axis current, so the integral method can be used to eliminate the flux error Δψ f , thus eliminating the second part of Equation 3.29.

[0220] The integral method is used to process the magnetic flux to obtain equation 3.32:

[0221]

[0222] In formula 3.32: K iψ is the integral compensation coefficient; ψ f1 is the model flux value after compensation, is the second intermediate value, and ψ f1 Substituting into equation 3.21, we can obtain the corrected q-axis voltage at the second moment.

[0223] Step 207 is the process of establishing the permanent magnet synchronous motor current loop predictive controller, and at the same time, the motor current error is eliminated using the current static error elimination algorithm to obtain a corrected control voltage.

[0224] Fig.12 The permanent magnet synchronous motor control system provided in this application is as follows: Fig.12As shown in the figure, the permanent magnet synchronous motor control system consists of a speed loop predictive controller and a current loop deadbeat predictive controller. In order to improve the operating stability of the system, the system's anti-disturbance capability is improved by expanding the state observer, and the current static error elimination algorithm is used to eliminate the current steady-state error caused by changes in motor parameters caused by the environment, which in turn leads to reduced system operating stability.

[0225] Fig.13 This is a comparison chart of speed response simulation under different control methods. Fig.14 This is the simulation diagram of the q-axis current response without the static error elimination algorithm. Fig.15 This is the simulation diagram of the q-axis current response when adding the static error elimination algorithm. Fig.13 As shown in the figure, the MPC+DPC control curve is the speed response of the control system with predictive controllers for the speed loop and current loop, the PI+PI curve is the speed response of the control system with PI controllers for both, and the MPC+ESO+DPC curve is the speed response of the control system with an extended state observer (ESO) added to the MPC curve system. By comparison, it can be found that MPC+ESO+DPC has no overshoot at startup, the shortest startup time, and the smallest steady-state fluctuation. After adding a torque disturbance at 0.2s, the recovery time is the shortest; and the speed fluctuation of the control system with the extended state observer is further reduced to 989-1002rpm, which is nearly halved, further enhancing the system's anti-disturbance capability.

[0226] Set the model flux to 10 times the actual value and the flux compensation coefficient to 100. The simulation results are as follows: Fig.14 and Fig.15 As shown, line 1 is the q-axis reference current, line 2 is the q-axis actual current, Fig.14 and Fig.15 It can be seen that after adding the static error elimination algorithm, the actual current response of the q-axis can closely follow the reference q-axis current. The current static error elimination algorithm eliminates the system operation stability problem caused by parameter mismatch.

[0227] This embodiment establishes a permanent magnet synchronous motor speed loop controller and a current zero-beat prediction controller; uses an extended state observer to observe system disturbances and perform feedforward to improve the system's anti-disturbance capability; eliminates current static errors through integration to eliminate system operation stability problems caused by parameter mismatch. The method provided in this embodiment can improve the control accuracy of the permanent magnet synchronous motor, improve the response speed, improve the anti-disturbance capability of the control system, and improve the steady-state accuracy of the control system.

[0228] Fig.16 A schematic diagram of the structure of a permanent magnet synchronous motor control device provided in an embodiment of the present application is shown in FIG. Fig.16 As shown, the device comprises:

[0229] The first determination unit 11 is used to determine the predicted speed value at the second moment according to the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment, wherein the second moment is the moment after the first moment and the third moment is the moment before the first moment.

[0230] An acquisition unit 12 is used to acquire a speed prediction error at a first moment, and process a predicted speed value at a second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment;

[0231] The second determination unit 13 is used to determine the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information, wherein the reference trajectory information is used to characterize the change process of the speed.

[0232] The control unit 14 is used to control the drilling operation of the permanent magnet synchronous motor according to the control current at the second moment.

[0233] For example, this embodiment can refer to the above method embodiment, and its principles and technical effects are similar and will not be described in detail.

[0234] Fig.17 A schematic diagram of another permanent magnet synchronous motor control device provided in an embodiment of the present application is shown in FIG. Fig.17 As shown, in Fig.16 On the basis of the device shown, the first determining unit 11 comprises:

[0235] The first determination module 111 is used to determine the Z-domain transfer function based on a preset permanent magnet motor mechanical motion relationship, where the Z-domain transfer function is used to determine the relationship between the rotation speed and the q-axis current change value.

[0236] The second determination module 112 is used to determine the relationship between the actual rotation speed value and the q-axis current change value according to the Z-domain transfer function.

[0237] The third determination module 113 is used to process the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment based on the relationship between the actual speed value and the q-axis current change value, so as to obtain the predicted speed value at the second moment, wherein the q-axis current change value at the first moment is the difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment.

[0238] In one example, an apparatus includes:

[0239] The establishing unit 15 is used to establish reference trajectory information according to the reference speed value and the actual speed value at the first moment before the second determining unit determines the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information.

[0240] In one example, the second determining unit 13 includes:

[0241] The fourth determination module 131 is used to determine the q-axis current error value at the second moment according to the processed predicted speed value at the second moment, the reference trajectory information, and the q-axis current change value at the first moment, wherein the q-axis current change value at the first moment is the difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at a third moment, and the third moment is before the first moment.

[0242] The fifth determination module 132 is configured to obtain the control current at the second moment according to the q-axis current error value at the second moment and the q-axis current actual value at the first moment.

[0243] In one example, the control unit 14 includes:

[0244] The acquisition module 141 is used to acquire the actual rotation speed value at the first moment and the current reference value at the first moment, and determine the current compensation value at the second moment.

[0245] The sixth determination module 142 is configured to compensate the control current at the second moment according to the current compensation value at the second moment to obtain the compensated control current at the second moment.

[0246] The control module 143 is used to control the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment.

[0247] In one example, the compensated control current at the second moment includes a d-axis current reference value at the second moment and a q-axis current reference value at the second moment; the control module 143 includes:

[0248] The acquisition submodule 1431 is used to acquire the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, and the motor state information.

[0249] The first determination submodule 1432 is configured to determine a voltage preset model according to a preset current preset model, wherein the current preset model represents the relationship between current and voltage.

[0250] The second determination submodule 1433 is used to process the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, the d-axis current reference value at the second moment, the q-axis current reference value at the second moment and the motor state information based on the voltage preset model to obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

[0251] In one example, the control module 143 includes:

[0252] The first correction submodule 1434 is used to correct the d-axis voltage at the second moment after the second determination submodule obtains the d-axis voltage at the second moment and the q-axis voltage at the second moment, so as to obtain a corrected d-axis voltage at the second moment.

[0253] The second correction submodule 1435 is used to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

[0254] In one example, the first correction submodule 1434 is specifically configured to:

[0255] A d-axis current reference value at a first moment is acquired, and an integration process is performed on the d-axis current reference value at the first moment to obtain a first intermediate value.

[0256] The d-axis voltage at the second moment is corrected according to the first intermediate value to obtain a corrected d-axis voltage at the second moment.

[0257] In one example, the second correction submodule 1435 is specifically configured to:

[0258] A q-axis current reference value at a first moment is acquired, and an integration process is performed on the q-axis current reference value at the first moment to obtain a second intermediate value.

[0259] The flux linkage value of the permanent magnet synchronous motor is compensated according to the second intermediate value to correct the q-axis voltage at the second moment to obtain the corrected q-axis voltage at the second moment.

[0260] In one example, the motor state information includes: an actual speed value of the permanent magnet synchronous motor, a resistance of the permanent magnet synchronous motor, an inductance of the permanent magnet synchronous motor, and a flux linkage value of the permanent magnet synchronous motor.

[0261] For example, this embodiment can refer to the above method embodiment, and its principles and technical effects are similar and will not be described in detail.

[0262] Fig.18 A block diagram of an electronic device provided in an embodiment of the present application, the electronic device is applied to a permanent magnet synchronous motor, such as Fig.18 As shown, the electronic device includes: a memory 71 and a processor 72.

[0263] The memory 71 is used to store processor executable instructions. Specifically, the executable instructions may include program codes, and the program codes include computer operation instructions. The memory may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk memory.

[0264] The processor 72 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present disclosure. The processor 72 may execute the method provided by any of the above embodiments.

[0265] Optionally, in a specific implementation, if the memory 71 and the processor 72 are implemented independently, the memory 71 and the processor 72 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Fig.18 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0266] Optionally, in a specific implementation, if the memory 71 and the processor 72 are integrated on a chip, the memory and the processor can communicate with each other through an internal interface.

[0267] Another embodiment of the present application further provides a permanent magnet synchronous motor, which includes the electronic device in the above embodiment.

[0268] Another embodiment of the present application further provides a rotary steerable drilling system, which includes a permanent magnet synchronous motor and a steering mechanism, wherein the steering mechanism is connected to the permanent magnet synchronous motor.

[0269] Yet another embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement a method as described in any of the above embodiments.

[0270] Yet another embodiment of the present application provides a computer program product, including a computer program, which implements the method in any of the above method embodiments when executed by a processor.

[0271] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0272] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A control method for a permanent magnet synchronous motor, characterized in that: The method is applied to a permanent magnet synchronous motor, and the method comprises: Determine a predicted speed value at a second moment according to an actual speed value at a first moment, an actual speed value at a third moment, and a q-axis current change value at the first moment, wherein the second moment is a moment after the first moment, and the third moment is a moment before the first moment; Obtaining a speed prediction error at the first moment, and processing a predicted speed value at the second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment; determining the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information, wherein the reference trajectory information is used to characterize the change process of the speed; controlling the drilling operation of the permanent magnet synchronous motor according to the control current at the second moment; The step of determining the predicted speed value at the second moment according to the actual speed value at the first moment, the actual speed value at the second moment, and the q-axis current change value at the first moment includes: Based on a preset permanent magnet motor mechanical motion relationship, a Z-domain transfer function is determined, wherein the Z-domain transfer function is used to determine a relationship between a rotational speed and a q-axis current change value; Determining the relationship between the actual rotation speed value and the q-axis current change value according to the Z-domain transfer function; Based on the relationship between the actual speed value and the q-axis current change value, the actual speed value at the first moment, the actual speed value at the second moment, and the q-axis current change value at the first moment are processed to obtain a predicted speed value at the second moment, wherein the q-axis current change value at the first moment is a difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment; The step of determining the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information includes: Determine the q-axis current error value at the second moment according to the processed predicted speed value at the second moment, the reference trajectory information, and the q-axis current change value at the first moment, wherein the q-axis current change value at the first moment is the difference between the q-axis current actual value at the first moment and the q-axis current actual value at a third moment, and the third moment is located before the first moment; The control current at the second moment is obtained according to the q-axis current error value at the second moment and the q-axis current actual value at the first moment.

2. The method according to claim 1, characterized in that Before determining the control current at the second moment according to the processed predicted speed value at the second moment and the preset reference trajectory information, the method further includes: The reference trajectory information is established according to the reference speed value and the actual speed value at the first moment.

3. The method according to claim 1 or 2, characterized in that: Controlling the drilling operation of the permanent magnet synchronous motor according to the control current at the second moment includes: Acquire an actual rotation speed value at a first moment and a current reference value at the first moment, and determine a current compensation value at the second moment; Compensating the control current at the second moment according to the current compensation value at the second moment to obtain a compensated control current at the second moment; The drilling operation of the permanent magnet synchronous motor is controlled according to the compensated control current at the second moment.

4. The method according to claim 3, characterized in that: The compensated control current at the second moment includes a d-axis current reference value at the second moment and a q-axis current reference value at the second moment; Controlling the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment includes: Acquire the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, and motor state information; According to a preset current preset model, wherein the current preset model represents the relationship between current and voltage, determine a voltage preset model; Based on the voltage preset model, the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, the d-axis current reference value at the second moment, the q-axis current reference value at the second moment and the motor status information are processed to obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

5. The method according to claim 4, characterized in that After obtaining the d-axis voltage at the second moment and the q-axis voltage at the second moment, the method further includes: The d-axis voltage at the second moment is corrected to obtain a corrected d-axis voltage at the second moment, and the q-axis voltage at the second moment is corrected to obtain a corrected q-axis voltage at the second moment.

6. The method according to claim 5, characterized in that Correcting the d-axis voltage at the second moment to obtain a corrected d-axis voltage at the second moment includes: Acquire a d-axis current reference value at the first moment, and perform integration processing on the d-axis current reference value at the first moment to obtain a first intermediate value; The d-axis voltage at the second moment is corrected according to the first intermediate value to obtain a corrected d-axis voltage at the second moment.

7. The method according to claim 5, characterized in that Correcting the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment includes: Acquire a q-axis current reference value at the first moment, and integrate the q-axis current reference value at the first moment to obtain a second intermediate value; The flux linkage value of the permanent magnet synchronous motor is compensated according to the second intermediate value to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

8. The method according to claim 4, characterized in that The motor state information includes: an actual rotation speed value of the permanent magnet synchronous motor, a resistance of the permanent magnet synchronous motor, an inductance of the permanent magnet synchronous motor, and a flux linkage value of the permanent magnet synchronous motor.

9. A permanent magnet synchronous motor control device, characterized in that: The device comprises: a first determining unit, configured to determine a predicted speed value at a second moment according to an actual speed value at a first moment, an actual speed value at a third moment, and a q-axis current change value at the first moment, wherein the second moment is a moment after the first moment, and the third moment is a moment before the first moment; an acquisition unit, configured to acquire a speed prediction error at the first moment, and process the predicted speed value at the second moment according to the speed prediction error at the first moment to obtain a processed predicted speed value at the second moment; a second determining unit, configured to determine the control current at the second moment according to the processed predicted speed value at the second moment and preset reference trajectory information, wherein the reference trajectory information is used to characterize a change process of the speed; A control unit, configured to control the drilling operation of the permanent magnet synchronous motor according to the control current at the second moment; The first determining unit includes: A first determination module is used to determine a Z-domain transfer function based on a preset permanent magnet motor mechanical motion relationship, wherein the Z-domain transfer function is used to determine a relationship between a rotation speed and a q-axis current change value; A second determination module is used to determine the relationship between the actual rotation speed value and the q-axis current change value according to the Z-domain transfer function; a third determination module, configured to process the actual speed value at the first moment, the actual speed value at the third moment, and the q-axis current change value at the first moment based on the relationship between the actual speed value and the q-axis current change value, so as to obtain a predicted speed value at the second moment, wherein the q-axis current change value at the first moment is a difference between the actual value of the q-axis current at the first moment and the actual value of the q-axis current at the third moment; The second determining unit includes: a fourth determination module, configured to determine a q-axis current error value at the second moment according to the processed predicted speed value at the second moment, the reference trajectory information, and the q-axis current change value at the first moment, wherein the q-axis current change value at the first moment is a difference between an actual value of the q-axis current at the first moment and an actual value of the q-axis current at a third moment, and the third moment is located before the first moment; The fifth determination module is used to obtain the control current at the second moment according to the q-axis current error value at the second moment and the actual value of the q-axis current at the first moment.

10. The device according to claim 9, characterized in that The device comprises: An establishing unit is used to establish the reference trajectory information according to the reference speed value and the actual speed value at the first moment before the second determining unit determines the control current at the second moment according to the processed predicted speed value and the preset reference trajectory information at the second moment.

11. The device according to claim 9 or 10, characterized in that The control unit comprises: An acquisition module, used to acquire an actual rotation speed value at a first moment and a current reference value at the first moment, and determine a current compensation value at the second moment; a sixth determining module, configured to compensate the control current at the second moment according to the current compensation value at the second moment to obtain the compensated control current at the second moment; A control module is used to control the drilling operation of the permanent magnet synchronous motor according to the compensated control current at the second moment.

12. The device according to claim 11, characterized in that The compensated control current at the second moment includes a d-axis current reference value at the second moment and a q-axis current reference value at the second moment; the control module includes: An acquisition submodule, used to acquire the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, and motor state information; A first determination submodule is used to determine a voltage preset model according to a preset current preset model, wherein the current preset model represents the relationship between current and voltage; The second determination submodule is used to process the actual value of the d-axis current at the first moment, the actual value of the q-axis current at the first moment, the d-axis current reference value at the second moment, the q-axis current reference value at the second moment and the motor state information based on the voltage preset model to obtain the d-axis voltage at the second moment and the q-axis voltage at the second moment.

13. The device according to claim 12, characterized in that The control module comprises: a first correction submodule, configured to correct the d-axis voltage at the second moment after the second determination submodule obtains the d-axis voltage at the second moment and the q-axis voltage at the second moment, so as to obtain a corrected d-axis voltage at the second moment; The second correction submodule is used to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

14. The device according to claim 13, characterized in that The first correction submodule is specifically used for: Acquire a d-axis current reference value at the first moment, and perform integration processing on the d-axis current reference value at the first moment to obtain a first intermediate value; The d-axis voltage at the second moment is corrected according to the first intermediate value to obtain a corrected d-axis voltage at the second moment.

15. The device according to claim 13, characterized in that The second correction submodule is specifically used for: Acquire a q-axis current reference value at the first moment, and integrate the q-axis current reference value at the first moment to obtain a second intermediate value; The flux linkage value of the permanent magnet synchronous motor is compensated according to the second intermediate value to correct the q-axis voltage at the second moment to obtain a corrected q-axis voltage at the second moment.

16. The device according to claim 13, characterized in that The motor state information includes: an actual rotation speed value of the permanent magnet synchronous motor, a resistance of the permanent magnet synchronous motor, an inductance of the permanent magnet synchronous motor, and a flux linkage value of the permanent magnet synchronous motor.

17. An electronic device, characterized in that: The electronic device is applied to a permanent magnet synchronous motor, and the electronic device comprises: a memory, a processor; A memory for storing instructions executable by the processor; The processor is used to execute the method according to any one of claims 1-8 according to the executable instructions.

18. A permanent magnet synchronous motor, characterized in that: The permanent magnet synchronous motor comprises the electronic device as claimed in claim 17.

19. A rotary steerable drilling system, characterized in that: The rotary steerable drilling system comprises the permanent magnet synchronous motor and a steering mechanism as claimed in claim 17, wherein the steering mechanism is connected to the permanent magnet synchronous motor.

20. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which are used to implement the method according to any one of claims 1 to 8 when executed by a processor.

21. A computer program product, characterized in that The invention comprises a computer program, which implements the method according to any one of claims 1 to 8 when being executed by a processor.

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