Model-free permanent magnet synchronous motor prediction control method and device, medium and equipment

Abstract

According to the model-free permanent magnet synchronous motor prediction control method and device, the medium and the equipment provided by the invention, after the current reference value and the current actual value under the current time step are compared, the corresponding model-free prediction controller can be determined according to the comparison result; then, the derivative of the current reference value of the permanent magnet synchronous motor under the current time step can be determined according to the current reference values under the current time step and the previous time step and the sampling time, and the current reference value under the current time step, the derivative of the current reference value and the actual current value are input into a model-free predictive controller; after a corresponding voltage instruction is input to the permanent magnet synchronous motor according to the control voltage, the anti-interference performance of the derivative of the current reference value is far greater than that of the derivative of the current actual value, so that the anti-interference performance of the current reference value is greatly improved. After the voltage instruction is input, the power consumption of the permanent magnet synchronous motor is not too high.

Description

Technical Field

[0001] The present application relates to the technical field of permanent magnet synchronous motors, and in particular to a model-free permanent magnet synchronous motor predictive control method, device, medium and equipment. Background Art

[0002] Permanent Magnet Synchronous Motor (PMSM) is an actuator that uses permanent magnets for excitation to achieve the conversion of electrical energy into mechanical energy. It has the advantages of small size, light weight, high power density, low loss and high reliability. It has been widely used in modern equipment such as robot dogs, electric vehicles, and CNC machine tools. PMSM is a complex system with multiple variables, strong coupling, and nonlinearity. To further improve its performance, researchers have proposed high-performance control strategies such as predictive control, sliding mode control, and neural network control.

[0003] At present, the permanent magnet synchronous motor control algorithm widely used in industry is mainly the proportional integral controller, which runs fast, but has large overshoot and average load resistance. The model prediction current control method that was subsequently generated uses a simple voltage and current model of the permanent magnet synchronous motor, but this method usually has static errors in tracking problems and must be compensated by an observer, resulting in a low calculation speed. The sliding mode controller, however, has large oscillations, which results in excessive power consumption of the motor. Summary of the invention

[0004] The purpose of the present application is to solve at least one of the above-mentioned technical defects, especially the technical defects that the permanent magnet synchronous motor control algorithm in the prior art has a general load resistance, a low calculation speed, and excessive motor power consumption.

[0005] The present application provides a model-free permanent magnet synchronous motor predictive control method, the method comprising:

[0006] Obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time;

[0007] After comparing the current reference value at the current time step with the current actual value, determining a corresponding model-free predictive controller according to the comparison result;

[0008] Determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference value at the current time step and the previous time step and the sampling time;

[0009] Inputting the current reference value, the derivative of the current reference value and the current actual value at the current time step into the model-free predictive controller to obtain the control voltage at the current time step output by the model-free predictive controller;

[0010] A corresponding voltage command is input to the permanent magnet synchronous motor according to the control voltage.

[0011] Optionally, the current reference value includes a q-axis current reference value;

[0012] The obtaining of the q-axis current reference value of the permanent magnet synchronous motor at the current time step includes:

[0013] Obtain the first speed tracking error of the permanent magnet synchronous motor at the current time step, the second speed tracking error at each time step before the current time step, and the PI control gain of the speed loop;

[0014] A q-axis current reference value of the permanent magnet synchronous motor at a current time step is calculated according to the first speed tracking error, the second speed tracking error, and the PI control gain.

[0015] Optionally, the current reference value includes a d-axis current reference value;

[0016] The obtaining of the d-axis current reference value of the permanent magnet synchronous motor at the current time step includes:

[0017] Determine the motor type for permanent magnet synchronous motors;

[0018] A d-axis current reference value of the permanent magnet synchronous motor at a current time step is determined according to the motor type.

[0019] Optionally, obtaining the actual current value of the permanent magnet synchronous motor at the current time step includes:

[0020] Get the three-phase current of the permanent magnet synchronous motor at the current time step;

[0021] The three-phase current is subjected to coordinate transformation to obtain the actual current value of the permanent magnet synchronous motor at the current time step.

[0022] Optionally, after comparing the current reference value at the current time step with the current actual value, determining a corresponding model-free predictive controller according to the comparison result includes:

[0023] Comparing the current reference value at the current time step with the current actual value to obtain a comparison result;

[0024] If the comparison result is that the current reference value at the current time step is not less than the current actual value, determining a first prediction controller;

[0025] If the comparison result is that the current reference value at the current time step is smaller than the current actual value, a second prediction controller is determined.

[0026] Optionally, the model-free predictive controller includes a first predictive controller and a second predictive controller;

[0027] The calculation formula of the first prediction controller is:

[0028]

[0029] The calculation formula of the second prediction controller is:

[0030]

[0031] in, is the control voltage for k time steps in the DC coordinate system, , is the derivative of the current reference value at time step k, is the current reference value at time step k, is the actual value of the current at time step k, , are the parameters of the first predictive controller or the second predictive controller, It is a non-physical attribute parameter. When the current reference value is the q-axis current reference value, , is the q-axis inductance, when the current reference value is the d-axis current reference value, , is the d-axis inductance.

[0032] Optionally, before inputting a corresponding voltage instruction to the permanent magnet synchronous motor according to the control voltage, the method further includes:

[0033] The control voltage of the current time step in the DC coordinate system is transformed to obtain the control voltage of the permanent magnet synchronous motor in the current time step in the two-phase stationary AC coordinate system.

[0034] The present application also provides a model-free permanent magnet synchronous motor predictive control device, comprising:

[0035] A data acquisition module is used to obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time;

[0036] A prediction controller determination module, used for comparing the current reference value at the current time step with the current actual value, and determining a corresponding model-free prediction controller according to the comparison result;

[0037] A current reference value derivative calculation module, used to determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference values ​​at the current time step and the previous time step and the sampling time;

[0038] A control voltage prediction module, used for inputting the current reference value, the derivative of the current reference value and the current actual value at the current time step into the model-free predictive controller to obtain the control voltage at the current time step output by the model-free predictive controller;

[0039] A voltage command input module is used to input a corresponding voltage command to the permanent magnet synchronous motor according to the control voltage.

[0040] The present application also provides a computer-readable storage medium, which stores computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the model-free permanent magnet synchronous motor predictive control method as described in any of the above embodiments.

[0041] The present application also provides a computer device, comprising: one or more processors, and a memory;

[0042] The memory stores computer-readable instructions, and when the computer-readable instructions are executed by the one or more processors, the steps of the model-free permanent magnet synchronous motor predictive control method as described in any one of the above embodiments are performed.

[0043] It can be seen from the above technical solutions that the embodiments of the present application have the following advantages:

[0044] The model-free permanent magnet synchronous motor predictive control method, device, medium and equipment provided in the present application can first obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time when controlling the permanent magnet synchronous motor; then, the present application can adopt different prediction methods according to the size of the current error value. Specifically, the present application can compare the current reference value at the current time step with the actual current value, and determine the corresponding model-free predictive controller according to the comparison result; further, in order to improve the anti-interference performance, the present application can also determine the permanent magnet synchronous motor at the current time step according to the current reference value and the sampling time at the previous time step. The derivative of the current reference value at the time step, and the current reference value at the current time step, the derivative of the current reference value and the actual current value are input into the model-free predictive controller, so as to quickly obtain the control voltage at the current time step output by the model-free predictive controller, and after inputting the corresponding voltage command to the permanent magnet synchronous motor according to the control voltage, since the anti-interference performance of the derivative of the current reference value of the present application is much greater than the derivative of the actual current value, after inputting the voltage command, it will not cause the permanent magnet synchronous motor to consume too much power, and the present application can quickly calculate the control voltage at the current time step through the model-free predictive controller, thereby effectively improving the calculation efficiency and reducing the calculation complexity, so as to better cope with the influence of unknown environment and disturbance. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0046] Figure 1 A schematic flow chart of a model-free permanent magnet synchronous motor predictive control method provided in an embodiment of the present application;

[0047] Figure 2 A schematic diagram of the relationship between the current error value and the items affected by the current error in the controller provided in an embodiment of the present application;

[0048] Figure 3 A diagram showing the architecture of a permanent magnet synchronous motor control system based on quasi-exponential model-free prediction provided in an embodiment of the present application;

[0049] Figure 4 The acceleration test performance effect diagram of the permanent magnet synchronous motor provided in the embodiment of the present application;

[0050] Figure 5A performance effect diagram of a loading and unloading experiment of a permanent magnet synchronous motor provided in an embodiment of the present application;

[0051] Figure 6 A schematic diagram of the structure of a model-free permanent magnet synchronous motor predictive control device provided in an embodiment of the present application;

[0052] Figure 7 A schematic diagram of the internal structure of a computer device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0053] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0054] In one embodiment, Figure 1 As shown, Figure 1 A flow chart of a model-free permanent magnet synchronous motor predictive control method provided in an embodiment of the present application; the present application provides a model-free permanent magnet synchronous motor predictive control method, the method may include:

[0055] S110: Obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time.

[0056] In this step, when controlling the permanent magnet synchronous motor, a basic model-free predictive control method can be used to calculate a control voltage with good disturbance performance by using the current reference value and the exponential current error term of the permanent magnet synchronous motor.

[0057] It is understood that the basic model-free predictive control method generally uses the following controller for prediction:

[0058]

[0059] in, and are the q-axis voltage and q-axis current derivatives of the permanent magnet synchronous motor, is the derivative of the q-axis current reference value, is a non-physical attribute parameter. are the unknown parts of the system and the unknown disturbances, is the observed value of the unknown disturbance, are the parameters of the controller, is the q-axis current error value.

[0060] However, since a disturbance observer is set in the above controller, the observation value of the disturbance observer needs to be calculated during calculation, which leads to high computational complexity and reduced computational efficiency. Therefore, this application makes improvements based on the above controller to improve the interpretability of model-free predictive control while reducing the computational complexity of existing model-free predictive control.

[0061] Based on this, the present application can obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, so that the current error value at the current time step can be calculated based on the actual current value and the current reference value at the current time step, and the derivative of the current reference value at the current time step can be calculated based on the actual current value at the current time step, the current reference value at the previous time step, and the sampling time. The derivative of the current reference value is used to improve the anti-winding performance, and the current error value is used to determine the final model-free predictive controller.

[0062] S120: After comparing the current reference value at the current time step with the current actual value, a corresponding model-free predictive controller is determined according to the comparison result.

[0063] In this step, after obtaining the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time through S110, the present application can compare the current reference value at the current time step with the actual current value, and determine the corresponding model-free predictive controller according to the comparison result.

[0064] Specifically, Figure 2 As shown, Figure 2 A schematic diagram of the relationship between the current error value and the items affected by the current error in the controller provided in an embodiment of the present application; Figure 2 In the figure, the horizontal axis is the current error value in amperes, the vertical axis is the item affected by the current error in the controller in amperes, Exp represents a quasi-exponential function, and error+ and error- refer to the error conditions where the current reference value minus the actual current value is greater than or equal to 0 and less than 0, respectively. Figure 2 The green line in the middle represents the relationship between the current error value in the existing controller and the items affected by the current error in the controller, and the pink line and the purple line represent the relationship between the improved current error value in the present application and the items affected by the current error in the controller.

[0065] The present application can pre-set different model-free predictive controllers according to the size of the current error value, and then after obtaining the current reference value and the actual current value at the current time step, compare the two and obtain the corresponding model-free predictive controller based on the comparison result. This can not only improve the accuracy of the model prediction results, but also reduce the calculation complexity.

[0066] S130: Determine a derivative of a current reference value of the permanent magnet synchronous motor at a current time step according to the current reference value at a current time step and a previous time step and a sampling time.

[0067] In this step, after obtaining the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time through S110, the present application can determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference value at the current time step and the previous time step and the sampling time, so that the control voltage at the current time step can be calculated according to the derivative of the current reference value at the current time step.

[0068] Specifically, since the current reference value of the present application can be a q-axis current reference value or a d-axis current reference value, the derivative of the current reference value of the present application can be a derivative of the q-axis current reference value or a derivative of the d-axis current reference value. The specific selection can be made according to actual conditions and is not limited here.

[0069] For example, when the present application obtains the q-axis current reference value of the permanent magnet synchronous motor at the current time step and the q-axis current reference value at the previous time step, the calculation formula of the derivative of the current reference value can be:

[0070]

[0071] in, is the derivative of the q-axis current reference value at k time steps, is the q-axis current reference value at k time steps, is the q-axis current reference value at k-1 time step, is the sampling time. Similarly, the derivative of the d-axis current reference value of the permanent magnet synchronous motor at the k time step can be obtained.

[0072] In addition, the present application can also expand the expression of the current reference value. From the most basic vector control structure, it can be seen that the current reference value is calculated by the speed loop controller. The specific derivation process is as follows:

[0073]

[0074] in, is the sampling time, and is the PI control gain of the speed loop, is the speed tracking error, and the current reference difference term can be finally simplified into a PD controller form using the speed loop PI control parameters, as shown in the above formula. In this application, the parameters of the permanent magnet synchronous motor speed control loop are all small parameters.

[0075] Furthermore, in order to compare the sensitivity difference between the current reference value and the current actual value derivative, the present application lists the basic formula of the current model:

[0076]

[0077] in, is the derivative of the actual value of the q-axis current at the k time step, is the control voltage of the q-axis at k time steps, is the stator resistance, is the actual value of the q-axis current at the k time step, is the electrical angular velocity at k time steps, is the d-axis inductance, is the actual value of the d-axis current at the k time step, is the permanent magnet flux, is the q-axis inductance.

[0078] When a small bias is given to each item, the sensitivity analysis formula for the item can be obtained:

[0079]

[0080] in, It is a small bias coefficient corresponding to the physical quantity. Obviously, in terms of order of magnitude, the anti-interference performance of the derivative of the actual current value is much weaker than that of the derivative of the reference current value.

[0081] S140: Inputting the current reference value, the derivative of the current reference value and the current actual value at the current time step into the model-free predictive controller to obtain the control voltage at the current time step output by the model-free predictive controller.

[0082] S150: Inputting corresponding voltage instructions to the permanent magnet synchronous motor according to the control voltage.

[0083] In the above steps, after determining the winning model-free predictive controller through S120 and determining the derivative of the current reference value of the permanent magnet synchronous motor at the current time step through S130, the present application can input the current reference value at the current time step, the derivative of the current reference value and the actual current value into the model-free predictive controller, and then obtain the control voltage at the current time step output by the model-free predictive controller, and input the control voltage into the permanent magnet synchronous motor as the voltage command of the permanent magnet synchronous motor, so as to drive the permanent magnet synchronous motor to reach the corresponding working state.

[0084] In the above embodiment, when the permanent magnet synchronous motor is controlled, the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time can be obtained first; then, the present application can adopt different prediction methods according to the size of the current error value. Specifically, the present application can compare the current reference value at the current time step with the actual current value, and determine the corresponding model-free predictive controller according to the comparison result; further, in order to improve the anti-interference performance, the present application can also determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference value and the sampling time at the current time step and the previous time step. The current reference value, the derivative of the current reference value and the actual current value at the current time step are input into the model-free predictive controller, and the control voltage at the current time step output by the model-free predictive controller can be quickly obtained. After the corresponding voltage command is input to the permanent magnet synchronous motor according to the control voltage, since the anti-interference performance of the derivative of the current reference value of the present application is much greater than the derivative of the actual current value, after the voltage command is input, it will not cause the permanent magnet synchronous motor to consume too much power, and the present application can quickly calculate the control voltage at the current time step through the model-free predictive controller, thereby effectively improving the calculation efficiency and reducing the calculation complexity, so as to better cope with the influence of unknown environment and disturbance.

[0085] In one embodiment, the current reference value may include a q-axis current reference value.

[0086] The q-axis current reference value of the permanent magnet synchronous motor at the current time step is obtained in S110, which may include:

[0087] S111: Obtaining a first speed tracking error of the permanent magnet synchronous motor at a current time step, a second speed tracking error at each time step before the current time step, and a PI control gain of a speed loop.

[0088] S112: Calculate a q-axis current reference value of the permanent magnet synchronous motor at a current time step according to the first speed tracking error, the second speed tracking error, and the PI control gain.

[0089] In this embodiment, when obtaining the current reference value of the permanent magnet synchronous motor, the q-axis current reference value can be obtained, and the d-axis current reference value can also be obtained. When obtaining the q-axis current reference value, the first speed tracking error of the permanent magnet synchronous motor at the current time step, the second speed tracking error at each time step before the current time step, and the PI control gain of the speed loop can be obtained first, so that the q-axis current reference value of the permanent magnet synchronous motor at the current time step can be calculated according to the first speed tracking error, the second speed tracking error and the PI control gain. The specific calculation formula is as follows:

[0090]

[0091] in, and is the PI control gain of the speed loop, is the velocity tracking error, .

[0092] In one embodiment, the current reference value may include a d-axis current reference value.

[0093] The d-axis current reference value of the permanent magnet synchronous motor at the current time step is obtained in S110, which may include:

[0094] S113: Determine the motor type of the permanent magnet synchronous motor.

[0095] S114: Determine a d-axis current reference value of the permanent magnet synchronous motor at a current time step according to the motor type.

[0096] In this embodiment, when the d-axis current reference value of the permanent magnet synchronous motor at the current time step is obtained, the present application can first determine the motor type of the permanent magnet synchronous motor, and then obtain the corresponding d-axis current reference value based on different motor types.

[0097] For example, current permanent magnet synchronous motors can be divided into two types: non-salient pole permanent magnet synchronous motors and salient pole permanent magnet synchronous motors. For the non-salient pole permanent magnet synchronous motor, its d-axis current reference value is 0, while for the salient pole permanent magnet synchronous motor, its d-axis current reference value is not 0. The specific value can be obtained according to the actual situation and will not be elaborated here.

[0098] In one embodiment, obtaining the actual current value of the permanent magnet synchronous motor at the current time step in S110 may include:

[0099] S115: Obtain the three-phase current of the permanent magnet synchronous motor at the current time step.

[0100] S116: Perform coordinate transformation on the three-phase current to obtain the actual current value of the permanent magnet synchronous motor at the current time step.

[0101] In this embodiment, since the permanent magnet synchronous motor is supplied with a three-phase sinusoidal voltage with a phase difference of 120° during application, and a rotation torque is obtained through vector operation to drive the rotor to rotate. Therefore, in order to obtain the actual value of the q-axis current or the actual value of the d-axis current, the present application can first obtain the three-phase current of the permanent magnet synchronous motor at the current time step, and then perform coordinate transformation on the three-phase current to obtain the actual current value of the permanent magnet synchronous motor at the current time step.

[0102] In one embodiment, after comparing the current reference value at the current time step with the current actual value in S120, determining the corresponding model-free predictive controller according to the comparison result may include:

[0103] S121: Compare the current reference value at the current time step with the current actual value to obtain a comparison result.

[0104] S122: If the comparison result is that the current reference value at the current time step is not less than the current actual value, a first prediction controller is determined.

[0105] S123: If the comparison result is that the current reference value at the current time step is smaller than the current actual value, a second prediction controller is determined.

[0106] In this embodiment, Figure 2 As shown, when the present application improves the control algorithm of the existing controller, the relationship between the current error value in the existing controller and the items affected by the current error in the controller can be divided into two sections according to the size of the current error value, wherein the pink line is the relationship between the current error value and the items affected by the current error in the controller when the current reference value is less than the actual current value, and the purple line is the relationship between the current error value and the items affected by the current error in the controller when the current reference value is not less than the actual current value. Figure 2 According to the characteristics of the pink line and the purple line, the present application can respectively construct corresponding model-free predictive controllers, that is, construct a first predictive controller when the current reference value is not less than the actual current value, and construct a second predictive controller when the current reference value is less than the actual current value. In this way, when it is determined that the current reference value is not less than the actual current value, the pre-constructed first predictive controller is used to predict the control voltage, and when it is determined that the current reference value is less than the actual current value, the pre-constructed second predictive controller is used to predict the control voltage, thereby improving the accuracy of the model prediction results and reducing the calculation complexity.

[0107] In one embodiment, the model-free predictive controller may include a first predictive controller and a second predictive controller.

[0108] The calculation formula of the first prediction controller is:

[0109]

[0110] The calculation formula of the second prediction controller is:

[0111]

[0112] in, is the control voltage for k time steps in the DC coordinate system, , is the derivative of the current reference value at time step k, is the current reference value at time step k, is the actual value of the current at time step k, , are the parameters of the first predictive controller or the second predictive controller, It is a non-physical attribute parameter. When the current reference value is the q-axis current reference value, , is the q-axis inductance, when the current reference value is the d-axis current reference value, , is the d-axis inductance.

[0113] Furthermore, when the present application obtains the actual value of the q-axis current and the reference value of the q-axis current, the above calculation formula can be transformed into:

[0114]

[0115] Similarly, the d-axis control voltage of k time steps in the DC coordinate system can be obtained.

[0116] Furthermore, in order to illustrate the beneficial effects of the above-mentioned model-free predictive controller of the present application, the present application constructs the following Figure 3 The permanent magnet synchronous motor control system architecture diagram based on quasi-index model-free prediction is shown in FIG. 1 ; after the permanent magnet synchronous motor predictive control method of the present application is applied to the control system, the following can be achieved: Figure 4-5 The experimental results shown. Figure 4 , Figure 5 It can be seen that when the control voltage calculated by the permanent magnet synchronous motor predictive control method of the present application is input into the control system, the sudden increase in the mechanical angular velocity of the permanent magnet synchronous motor is small, and returns to the normal value in a relatively short time. Moreover, after applying the q-axis control voltage command, the q-axis current can rise to the preset value in a relatively short time and then return to the normal value in a relatively short time. After applying the d-axis control voltage command, the oscillation amplitude of the d-axis current is relatively small, thereby reducing the power consumption of the motor.

[0117] In one embodiment, before inputting a corresponding voltage instruction to the permanent magnet synchronous motor according to the control voltage, the method may further include:

[0118] The control voltage of the current time step in the DC coordinate system is transformed to obtain the control voltage of the permanent magnet synchronous motor in the current time step in the two-phase stationary AC coordinate system.

[0119] In this embodiment, since the current is a vector, after obtaining the angle θ between the current vector and the α-axis in the permanent magnet synchronous motor through the encoder, the dq coordinate system can be converted to the α-β coordinate system according to the control voltage of the d-axis, the control voltage of the q-axis and the angle θ, and then the control voltage in the two-phase stationary coordinate system can be obtained. and .

[0120] The model-free permanent magnet synchronous motor predictive control device provided in an embodiment of the present application is described below. The model-free permanent magnet synchronous motor predictive control device described below and the model-free permanent magnet synchronous motor predictive control method described above can be referenced to each other.

[0121] In one embodiment, Figure 6 As shown, Figure 6 A schematic diagram of the structure of a model-free permanent magnet synchronous motor predictive control device provided in an embodiment of the present application; the present application also provides a model-free permanent magnet synchronous motor predictive control device, which may include a data acquisition module 210, a predictive controller determination module 220, a derivative calculation module 230, a control voltage prediction module 240, and a voltage command input module 250, specifically including the following:

[0122] The data acquisition module 210 is used to obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time.

[0123] The prediction controller determination module 220 is used to compare the current reference value at the current time step with the current actual value, and determine the corresponding model-free prediction controller according to the comparison result.

[0124] The current reference value derivative calculation module 230 is used to determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference values ​​at the current time step and the previous time step and the sampling time.

[0125] The control voltage prediction module 240 is used to input the current reference value, the derivative of the current reference value and the current actual value at the current time step into the model-free predictive controller to obtain the control voltage at the current time step output by the model-free predictive controller.

[0126] The voltage command input module 250 is used to input a corresponding voltage command to the permanent magnet synchronous motor according to the control voltage.

[0127] In the above embodiment, when the permanent magnet synchronous motor is controlled, the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time can be obtained first; then, the present application can adopt different prediction methods according to the size of the current error value. Specifically, the present application can compare the current reference value at the current time step with the actual current value, and determine the corresponding model-free predictive controller according to the comparison result; further, in order to improve the anti-interference performance, the present application can also determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference value and the sampling time at the current time step and the previous time step. The current reference value, the derivative of the current reference value and the actual current value at the current time step are input into the model-free predictive controller, and the control voltage at the current time step output by the model-free predictive controller can be quickly obtained. After the corresponding voltage command is input to the permanent magnet synchronous motor according to the control voltage, since the anti-interference performance of the derivative of the current reference value of the present application is much greater than the derivative of the actual current value, after the voltage command is input, it will not cause the permanent magnet synchronous motor to consume too much power, and the present application can quickly calculate the control voltage at the current time step through the model-free predictive controller, thereby effectively improving the calculation efficiency and reducing the calculation complexity, so as to better cope with the influence of unknown environment and disturbance.

[0128] In one embodiment, the present application also provides a computer-readable storage medium, which stores computer-readable instructions. When the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the model-free permanent magnet synchronous motor predictive control method as described in any of the above embodiments.

[0129] In one embodiment, the present application also provides a computer device, including: one or more processors, and a memory.

[0130] The memory stores computer-readable instructions, and when the computer-readable instructions are executed by the one or more processors, the steps of the model-free permanent magnet synchronous motor predictive control method as described in any one of the above embodiments are performed.

[0131] Indicatively, Figure 7 As shown, Figure 7 This is a schematic diagram of the internal structure of a computer device provided in an embodiment of the present application. The computer device 300 may be provided as a server. Figure 7The computer device 300 includes a processing component 302, which further includes one or more processors, and a memory resource represented by a memory 301 for storing instructions executable by the processing component 302, such as an application. The application stored in the memory 301 may include one or more modules, each corresponding to a set of instructions. In addition, the processing component 302 is configured to execute instructions to perform the model-free permanent magnet synchronous motor predictive control method of any of the above embodiments.

[0132] The computer device 300 may further include a power supply component 303 configured to perform power management of the computer device 300, a wired or wireless network interface 304 configured to connect the computer device 300 to a network, and an input / output (I / O) interface 305. The computer device 300 may operate based on an operating system stored in the memory 301, such as Windows Server TM, Mac OS X TM, Unix TM, Linux TM, Free BSD TM, or the like.

[0133] Those skilled in the art will understand that Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0134] Finally, it should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0135] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can refer to each other.

[0136] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A model-free permanent magnet synchronous motor predictive control method, characterized in that: The method comprises: Obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time; After comparing the current reference value at the current time step with the current actual value, determining a corresponding model-free predictive controller according to the comparison result; Determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference value at the current time step and the previous time step and the sampling time; Inputting the current reference value, the derivative of the current reference value and the current actual value at the current time step into the model-free predictive controller to obtain the control voltage at the current time step output by the model-free predictive controller; A corresponding voltage command is input to the permanent magnet synchronous motor according to the control voltage.

2. The model-free permanent magnet synchronous motor predictive control method according to claim 1, characterized in that: The current reference value includes a q-axis current reference value; The obtaining of the q-axis current reference value of the permanent magnet synchronous motor at the current time step includes: Obtain the first speed tracking error of the permanent magnet synchronous motor at the current time step, the second speed tracking error at each time step before the current time step, and the PI control gain of the speed loop; A q-axis current reference value of the permanent magnet synchronous motor at a current time step is calculated according to the first speed tracking error, the second speed tracking error, and the PI control gain.

3. The model-free permanent magnet synchronous motor predictive control method according to claim 1, characterized in that: The current reference value includes a d-axis current reference value; The obtaining of the d-axis current reference value of the permanent magnet synchronous motor at the current time step includes: Determine the motor type for permanent magnet synchronous motors; A d-axis current reference value of the permanent magnet synchronous motor at a current time step is determined according to the motor type.

4. The model-free permanent magnet synchronous motor predictive control method according to any one of claims 1 to 3, characterized in that: The obtaining of the actual current value of the permanent magnet synchronous motor at the current time step includes: Get the three-phase current of the permanent magnet synchronous motor at the current time step; The three-phase current is subjected to coordinate transformation to obtain the actual current value of the permanent magnet synchronous motor at the current time step.

5. The model-free permanent magnet synchronous motor predictive control method according to claim 1, characterized in that: After comparing the current reference value at the current time step with the current actual value, determining a corresponding model-free predictive controller according to the comparison result includes: Comparing the current reference value at the current time step with the current actual value to obtain a comparison result; If the comparison result is that the current reference value at the current time step is not less than the current actual value, determining a first prediction controller; If the comparison result is that the current reference value at the current time step is smaller than the current actual value, a second prediction controller is determined.

6. The model-free permanent magnet synchronous motor predictive control method according to claim 1, characterized in that: The model-free predictive controller includes a first predictive controller and a second predictive controller; The calculation formula of the first prediction controller is: The calculation formula of the second prediction controller is: in, is the control voltage for k time steps in the DC coordinate system, , is the derivative of the current reference value at time step k, is the current reference value at time step k, is the actual value of the current at time step k, , are the parameters of the first predictive controller or the second predictive controller, It is a non-physical attribute parameter. When the current reference value is the q-axis current reference value, , is the q-axis inductance, when the current reference value is the d-axis current reference value, , is the d-axis inductance.

7. The model-free permanent magnet synchronous motor predictive control method according to claim 6, characterized in that: Before inputting a corresponding voltage instruction to the permanent magnet synchronous motor according to the control voltage, the method further includes: The control voltage of the current time step in the DC coordinate system is transformed to obtain the control voltage of the permanent magnet synchronous motor in the current time step in the two-phase stationary AC coordinate system.

8. A model-free permanent magnet synchronous motor predictive control device, characterized in that: include: A data acquisition module is used to obtain the actual current value and current reference value of the permanent magnet synchronous motor at the current time step, the current reference value at the previous time step, and the sampling time; A prediction controller determination module, used for comparing the current reference value at the current time step with the current actual value, and determining a corresponding model-free prediction controller according to the comparison result; A current reference value derivative calculation module, used to determine the derivative of the current reference value of the permanent magnet synchronous motor at the current time step according to the current reference values ​​at the current time step and the previous time step and the sampling time; A control voltage prediction module, used for inputting the current reference value, the derivative of the current reference value and the current actual value at the current time step into the model-free predictive controller to obtain the control voltage at the current time step output by the model-free predictive controller; A voltage command input module is used to input a corresponding voltage command to the permanent magnet synchronous motor according to the control voltage.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-readable instructions, and when the computer-readable instructions are executed by one or more processors, the one or more processors execute the steps of the model-free permanent magnet synchronous motor predictive control method as described in any one of claims 1 to 7.

10. A computer device, characterized in that: include: one or more processors, and memory; The memory stores computer-readable instructions, and when the computer-readable instructions are executed by the one or more processors, the steps of the model-free permanent magnet synchronous motor predictive control method as claimed in any one of claims 1 to 7 are performed.

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