Permanent magnet motor direct torque control method and system based on model prediction and medium

Abstract

The invention discloses a permanent magnet motor direct torque control method and system based on model prediction and a medium, and belongs to the technical field of permanent magnet synchronous motor control. According to the permanent magnet synchronous motor direct torque control method based on model prediction, two-phase current of a permanent magnet synchronous motor is processed by constructing a Clarke transformation model, a flux linkage and torque model, a voltage vector optimization model, a switching time calculation model, a cost function minimization model and a three-phase inverter control model, a space voltage vector is determined, and the direct torque of the permanent magnet synchronous motor is obtained. And switching action information of a switching tube is obtained and is used for controlling bus voltage to be input into the permanent magnet synchronous motor, so that the permanent magnet synchronous motor is driven, and direct torque control of the permanent magnet synchronous motor based on model prediction is completed, and therefore, the switching state of a switch can be controlled to be optimal, and torque pulsation is effectively reduced; therefore, the system operation efficiency is effectively improved, the system stability is improved, the switching loss is reduced, and the scheme is scientific, reasonable and feasible.

Description

Technical Field

[0001] The invention relates to a method, system and medium for direct torque control of a permanent magnet motor based on model prediction, and belongs to the technical field of permanent magnet synchronous motor control. Background Art

[0002] The control method of permanent magnet synchronous motor without position sensor has the advantages of simple structure, high reliability and high efficiency, and has become one of the key technologies for realizing high-performance control of permanent magnet synchronous motor. At present, the high-performance control methods applied to permanent magnet synchronous motor are mainly: vector control and direct torque control. For example, the invention patent (CN202210740401.5) proposes a surface-mounted permanent magnet synchronous motor vector control method based on non-singular fast terminal sliding mode observer, which realizes effective tracking of motor speed in practical applications and improves the steady-state accuracy of the system. However, when the external input load torque changes, there is a more obvious torque jitter phenomenon, which reduces the robustness of the sliding mode control system. For example, the invention patent (CN202210477784.1) proposes a sliding mode control method for permanent magnet synchronous motor based on improved variable gain reaching law, which optimizes the fixed gain value of the exponential reaching law to a variable gain value that is continuously adaptively adjusted, which can effectively solve the problem of low speed when far away from the sliding surface, and suppress the high-frequency jitter phenomenon during sliding mode control, but the jitter phenomenon cannot be completely eliminated when the system approaches the sliding surface. The above methods often rely on motor models and are easily affected by changes in motor parameters. However, direct torque control is less dependent on motor parameters and is a hot topic in current research. For example, the invention patent (CN 202310588541.X) proposes a method for optimizing PID permanent magnet synchronous motor direct torque control based on an improved gradient optimization algorithm. The improved gradient optimization algorithm is used to optimize the speed loop parameters, but the algorithm introduces a weight factor, which increases the complexity of the system. For example, the invention patent (CN202311159107.6) proposes a general direct torque control method using discrete virtual vectors. By re-establishing the vector selection switch table, the purpose of suppressing torque fluctuations is achieved. However, the duty cycle calculation of this method is complex and increases the dependence on motor parameters.

[0003] Model predictive control is relatively flexible and makes up for the shortcomings of the above-mentioned traditional control methods in some aspects. Therefore, it has received widespread attention and has been well developed. However, the traditional model predictive torque control method needs to calculate the predicted torque and flux corresponding to all candidate vectors in a finite set according to the prediction model of the control object, and evaluate each predicted state with a cost function representing the control target, and select the switching state that can minimize the cost function as the next output of the controller. Therefore, the system has the defects of high switching frequency, and there are problems of large torque pulsation and flux pulsation, which leads to low efficiency and large switching losses. For example, the invention patent (CN202210258167.2) proposes to add a discrete space vector modulation model to the permanent magnet synchronous motor predictive torque control method, and select the target voltage vector that meets the minimum cost function from the range selected by the target small virtual voltage vector. This method reduces the time to calculate the target voltage vector, but the patent still has problems such as large torque pulsation and slow response time in practical applications. For example, the invention patent (CN202010257407.8) proposes a finite set multi-step model predictive torque control method for a permanent magnet synchronous motor with a weightless factor and variable switching points. An improved multi-step model predictive controller with variable switching points is designed in the inner loop to replace the traditional table lookup method, which reduces the switching frequency. However, this method still has the problem of large torque pulsation.

[0004] The information disclosed in this Background Art is only for understanding the background of the inventive concept and therefore it may include information that does not constitute the prior art. Summary of the invention

[0005] In response to the above problem or one of the above problems, an object of the present invention is to provide a method for direct torque control of a permanent magnet motor based on model prediction. By constructing a Clarke transformation model, a flux and torque model, a voltage vector optimization model, a switching time calculation model, a cost function minimization model, and a three-phase inverter control model, the two-phase current of the permanent magnet synchronous motor is processed, the spatial voltage vector is determined, and the switching action information of the switch tube is obtained, which is used to control the bus voltage input into the permanent magnet synchronous motor, realize the drive of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction, so as to achieve the optimal switching state of the control switch, effectively reduce the torque pulsation, and then effectively improve the system operation efficiency, improve the system stability and reduce the switching loss. The scheme is scientific, reasonable and feasible.

[0006] In response to the above problem or one of the above problems, the second object of the present invention is to provide a method, system and medium for direct torque control of a permanent magnet motor based on model prediction. The two-phase current of the permanent magnet synchronous motor is processed through model prediction, the spatial voltage vector is determined, and the switching action information of the switch tube is obtained, which is used to control the bus voltage input into the permanent magnet synchronous motor, realize the drive of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction, so as to achieve the optimal switching state of the control switch, effectively reduce the torque pulsation, and then effectively improve the system operation efficiency, improve the system stability and reduce the switching loss.

[0007] To achieve one of the above purposes, the first technical solution of the present invention is:

[0008] The method of direct torque control of permanent magnet synchronous motor based on model prediction includes the following contents:

[0009] The pre-built Clarke transformation model is used to process the collected two-phase currents of the permanent magnet synchronous motor to obtain the transformation current;

[0010] The pre-built flux and torque model is used to process the conversion current to obtain the stator flux angle change, electromagnetic torque and stator flux;

[0011] Using the pre-built space voltage vector optimization model, the stator flux angle change, electromagnetic torque and stator flux are processed to obtain the space voltage optimization vector;

[0012] Using the pre-built switching time calculation model, the spatial voltage optimization vector is processed to obtain the switching time;

[0013] Based on the pre-built cost function minimization model, the switching time is processed to obtain the spatial voltage vector;

[0014] Through the pre-built three-phase inverter control model, the switching action information of the switch tube is obtained according to the space voltage vector, which is used to control the bus voltage input to the permanent magnet synchronous motor, realize the drive of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction.

[0015] After continuous exploration and experiments, the present invention constructs a Clarke transformation model, a flux and torque model, a voltage vector optimization model, a switching time calculation model, a cost function minimization model, and a three-phase inverter control model to process the two-phase current of the permanent magnet synchronous motor, determine the spatial voltage vector, and obtain the switching action information of the switch tube, which is used to control the bus voltage input into the permanent magnet synchronous motor, realize the driving of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction, so as to achieve the optimal switching state of the control switch, effectively reduce the torque pulsation, and then effectively improve the system operation efficiency, improve the system stability and reduce the switching loss. The scheme is scientific, reasonable and feasible.

[0016] As the preferred technical measures:

[0017] The method of processing the collected two-phase current of the permanent magnet synchronous motor by using the pre-built Clarke transformation model to obtain the transformation current is as follows:

[0018] The two-phase current i of the permanent magnet synchronous motor in the three-phase coordinate system is obtained by collecting current signals with two Hall current sensors. a and i b ;

[0019] The transformation formula of the Clarke transformation model is constructed as follows:

[0020]

[0021] Among them, the phase current i c Through the formula i a +i b +i c =0 calculated;

[0022] Based on the transformation formula, the two-phase current i a and i b Calculate and obtain the conversion current (i α (k) and i β (k)).

[0023] As the preferred technical measures:

[0024] The method of processing the conversion current using the pre-built flux and torque model to obtain the stator flux angle change, electromagnetic torque and stator flux is as follows:

[0025] The voltage equation of the permanent magnet synchronous motor in the rotating coordinate system dq is established, and its expression is as follows:

[0026]

[0027] The torque equation of the permanent magnet synchronous motor is established, and its expression is as follows:

[0028]

[0029] In the formula, R s is the stator resistance, u d 、u q is the dq axis stator voltage, i d 、i q is the dq axis stator current, ψ f is the stator flux, L d , L q is the dq axis inductance, T e is the load torque, P n is the pole pair number, ω e is the electrical angular velocity of the motor rotor;

[0030] Based on the voltage equation, the stator current equation in the rotating coordinate system dq is obtained:

[0031]

[0032] The stator current equation is discretized by first-order forward difference to obtain the discretized current equation:

[0033]

[0034] In the formula, i d(k+1) ,i q(k+1) are the predicted values ​​of the d-axis and q-axis stator current components at time k+1, u d(k) 、u q(k) is the d-axis and q-axis stator voltage at time k, i d(k) ,i q(k) are the components of the d-axis and q-axis stator currents at time k, ω e(k) is the electrical angular velocity of the motor rotor at time k.

[0035] For surface mounted permanent magnet synchronous motors, L d =L q , transform the torque equation and get the new torque equation:

[0036]

[0037] Based on the new torque equation and the discretized current equation, the torque flux prediction formula of the permanent magnet synchronous motor is established, and its expression is as follows:

[0038]

[0039] Where, T e (k+1),ψ s(k+1) are the predicted values ​​of electromagnetic torque and stator flux at time k+1, ψ d (k+1),ψ q (k+1) are the predicted values ​​of the d-axis and q-axis stator flux components at time k+1 respectively.

[0040] Using the torque flux prediction formula, the stator flux angle change θ is calculated f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1).

[0041] As the preferred technical measures:

[0042] Using the pre-built space voltage vector optimization model, the stator flux angle change, electromagnetic torque and stator flux are processed to obtain the space voltage optimization vector as follows:

[0043] The cost function is designed based on the minimum torque ripple principle, and the electromagnetic torque and stator flux are used as evaluation indicators of the controller performance to predict the controlled variable F at time k+1. The calculation formula is as follows:

[0044]

[0045] in and are the reference values ​​of torque and flux respectively; coefficient Q is the weight coefficient, T e is the electromagnetic torque, ψ s is the stator flux, k is the kth moment;

[0046] A new type of space voltage vector switch table is set to select two optimal space voltage vectors, namely, space voltage optimization vectors. The input of the new type of space voltage vector switch table is the sector where the stator flux vector is located and the torque. U1 to U6 represent six space voltage vectors, S1 to S6 represent sectors 1 to 6, ΔT>0 represents increasing torque, and ΔT<0 represents decreasing torque.

[0047] When considering the torque performance, four space voltage vectors for clockwise and counterclockwise rotation directions are selected; for the stator flux performance, it is already included in the minimum value of the cost function;

[0048] According to the stator flux angle change θ f and torque offset ΔT e Select the space voltage optimization vector, and its calculation formula is as follows:

[0049]

[0050] In the formula, ψ α and ψ βThey are the stator flux components of the α and β axes respectively.

[0051] The principle of selecting two spatial voltage optimization vectors depends on the stator flux θ f and torque offset T e , when a zero space voltage vector U0 does not provide a zero torque offset; to reduce switching losses, only one bridge arm is changed, and switching transitions are reduced by applying U0 and U7.

[0052] As the preferred technical measures:

[0053] The method of processing the spatial voltage optimization vector using the pre-built switching time calculation model to obtain the switching time is as follows:

[0054] According to the torque performance linearization characteristics, the torque size at k+1 is predicted; a virtual space voltage vector is applied to the on-time t of the duty cycle on , a zero-space voltage vector is applied to control the duty cycle at the cut-off time t off ; The calculation formula of the torque at k+1 is as follows:

[0055]

[0056] Where l1 and l2 are the torque differential coefficients of the virtual space voltage vector and the zero space voltage vector respectively; the average torque control has a function that keeps the torque within the torque inertia delay δT bandwidth, and its calculation formula is as follows:

[0057]

[0058] By solving the stator flux angle change θ f Calculate the torque offset ΔT using the formula e Indicates the switching time t on ;

[0059] The switching time t is calculated by using the spatial voltage vector, current, stator flux position and electric rotor position. on ;

[0060] Applying the virtual space voltage vector, the switching time, i.e. the switching time, is obtained. The switching time calculation formula is as follows:

[0061]

[0062] The cut-off time t of the zero-space voltage vector control duty cycle is off The calculation formula is as follows:

[0063] t off =T s -t on .

[0064] As the preferred technical measures:

[0065] Based on the pre-built cost function minimization model, the switching time is processed to obtain the space voltage vector as follows:

[0066] Firstly, the vector selection and space voltage vector and cost function optimization are performed, and then the cost function is evaluated;

[0067] Due to the adoption of average torque control, the calculation time is reduced without affecting the torque performance;

[0068] The switching time of each of the three space voltage vectors is calculated using the switching time calculation formula, and the variables in (k+1) are predicted;

[0069] A virtual space voltage vector and a zero space voltage vector are operated in each sampling time, and the output of the switching time and speed PI controller is and reference value of magnetic linkage After processing, the space voltage vector S is obtained A , S B and S C .

[0070] As the preferred technical measures:

[0071] Through the pre-built three-phase inverter control model, according to the space voltage vector, the switching action information of the switch tube is obtained to control the bus voltage input to the permanent magnet synchronous motor. The method for driving the permanent magnet synchronous motor is as follows:

[0072] A three-phase inverter is provided, which is a typical two-level three-phase voltage source inverter, consisting of three upper and lower bridge arms, which includes six switching devices;

[0073] The space voltage vector S A , S B and S C It is applied to the six switch devices respectively, and the six switch tubes are switched to control the bus voltage U dc Input to permanent magnet synchronous motor;

[0074] When an upper bridge arm switch device is turned on, the bus voltage is applied to the motor stator winding from the upper bridge arm switch device; through a series of on-off combinations, the bus voltage is regularly applied to the motor, thereby driving the motor and realizing the driving of the permanent magnet synchronous motor.

[0075] To achieve one of the above purposes, the second technical solution of the present invention is:

[0076] The method for direct torque control of a permanent magnet synchronous motor based on model prediction comprises the following steps:

[0077] Step 1: collect the two-phase current (i a 、i b and i c );

[0078] Step 2: Using the pre-built Clarke transformation model, the collected two-phase current (i a 、i b and i c ) is processed to obtain the conversion current i α (k) and i β (k);

[0079] Step 3: Use the pre-built flux and torque model to transform the current i α (k) and i β (k) is processed to obtain the stator flux angle change θ f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1);

[0080] Step 4: Use the pre-built space voltage vector optimization model to calculate the stator flux angle change θ f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1) is processed to obtain the spatial voltage optimization vector U f1,f2,f3,f4,f5,f6 ;

[0081] Step 5: Use the pre-built switching time calculation model to process the spatial voltage optimization vector, current, stator flux position, and electric rotor position to obtain the switching time t on1,on2,on3,on4,on5,on6 ;

[0082] Step 6: Minimize the output of the switching time and speed PI controller based on the pre-built cost function model and reference value of magnetic linkage After processing, the space voltage vector S is obtained A , S B and S C ;

[0083] Step 7: Based on the pre-built three-phase inverter control model, the space voltage vector S A , S B and S C , get the switch action information of the switch tube, which is used to control the bus voltage U dc The input is then fed into the permanent magnet synchronous motor to drive the permanent magnet synchronous motor.

[0084] To achieve one of the above purposes, the third technical solution of the present invention is:

[0085] The permanent magnet synchronous motor direct torque control system based on model prediction includes a permanent magnet synchronous motor, a two-phase Hall current sensor, a Clarke transformation module, a flux linkage and torque prediction control module, a sliding mode observer, an inverter and a first subtractor:

[0086] The two-phase current i of the permanent magnet synchronous motor is collected by using the two-phase Hall current sensor sampling method. a 、i b and i c As the input of the Clarke transform module, the output of the Clarke transform module i α (k) and i β (k) are used as the input of the flux and torque prediction control module and the sliding mode observer respectively; the spatial voltage vector S of the permanent magnet synchronous motor PMSM is obtained by using the flux and torque prediction control module. A , S B and S C As the input of the inverter, the input of the first subtractor is the given speed n * (k) and the output n(k) of the sliding mode observer, thereby obtaining the output Δn of the first subtractor * (k).

[0087] To achieve one of the above purposes, the fourth technical solution of the present invention is:

[0088] An electronic device comprising:

[0089] one or more processors;

[0090] A storage device for storing one or more programs;

[0091] When the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned permanent magnet synchronous motor direct torque control method based on model prediction.

[0092] To achieve one of the above purposes, the fifth technical solution of the present invention is:

[0093] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned permanent magnet synchronous motor direct torque control method based on model prediction.

[0094] Compared with the prior art solutions, the present invention has the following beneficial effects:

[0095] After continuous exploration and experiments, the present invention constructs a Clarke transformation model, a flux and torque model, a voltage vector optimization model, a switching time calculation model, a cost function minimization model, and a three-phase inverter control model to process the two-phase current of the permanent magnet synchronous motor, determine the spatial voltage vector, and obtain the switching action information of the switch tube, which is used to control the bus voltage input into the permanent magnet synchronous motor, realize the driving of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction, so as to achieve the optimal switching state of the control switch, effectively reduce the torque pulsation, and then effectively improve the system operation efficiency, improve the system stability and reduce the switching loss. The scheme is scientific, reasonable and feasible.

[0096] After continuous exploration and experiments, the present invention processes the two-phase current of the permanent magnet synchronous motor through model prediction, determines the spatial voltage vector, and obtains the switching action information of the switch tube, which is used to control the bus voltage input into the permanent magnet synchronous motor, realize the driving of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction, so as to achieve the optimal switching state of the control switch, effectively reduce the torque pulsation, and then effectively improve the system operation efficiency, improve the system stability and reduce the switching loss. The scheme is scientific, reasonable and feasible. BRIEF DESCRIPTION OF THE DRAWINGS

[0097] Figure 1 A structural block diagram of a direct torque control system of a permanent magnet synchronous motor according to the present invention;

[0098] Figure 2 A principle block diagram of a direct torque control method for a permanent magnet synchronous motor according to the present invention;

[0099] Figure 3 This is a schematic diagram of average torque control principle of the permanent magnet synchronous motor direct torque control system of the present invention. DETAILED DESCRIPTION

[0100] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0101] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the following detailed description of the present invention. Those skilled in the art can fully understand the present invention without the description of these details.

[0102] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention pertains. The terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "or / and" as used herein includes any and all combinations of one or more of the associated listed items.

[0103] The first specific embodiment of the method for direct torque control of a permanent magnet synchronous motor based on model prediction of the present invention:

[0104] The method of direct torque control of permanent magnet synchronous motor based on model prediction includes the following contents:

[0105] The pre-built Clarke transformation model is used to process the collected two-phase currents of the permanent magnet synchronous motor to obtain the transformation current;

[0106] The pre-built flux and torque model is used to process the conversion current to obtain the stator flux angle change, electromagnetic torque and stator flux;

[0107] Using the pre-built space voltage vector optimization model, the stator flux angle change, electromagnetic torque and stator flux are processed to obtain the space voltage optimization vector;

[0108] Using the pre-built switching time calculation model, the spatial voltage optimization vector is processed to obtain the switching time;

[0109] Based on the pre-built cost function minimization model, the switching time is processed to obtain the spatial voltage vector;

[0110] Through the pre-built three-phase inverter control model, the switching action information of the switch tube is obtained according to the space voltage vector, which is used to control the bus voltage input to the permanent magnet synchronous motor, realize the drive of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction.

[0111] In this embodiment, the method of using the pre-built Clarke transformation model to process the collected two-phase current of the permanent magnet synchronous motor to obtain the transformation current is as follows:

[0112] The two-phase current i of the permanent magnet synchronous motor in the three-phase coordinate system is obtained by collecting current signals with two Hall current sensors. a and i b ;

[0113] The transformation formula of the Clarke transformation model is constructed as follows:

[0114]

[0115] Among them, the phase current i c Through the formula i a +i b +i c =0 calculated;

[0116] Based on the transformation formula, the two-phase current i a and i b Calculate and obtain the conversion current (i α (k) and i β (k)).

[0117] In this embodiment: the pre-built flux and torque model is used to process the conversion current to obtain the stator flux angle change, electromagnetic torque and stator flux as follows:

[0118] The voltage equation of the permanent magnet synchronous motor in the rotating coordinate system dq is established, and its expression is as follows:

[0119]

[0120] The torque equation of the permanent magnet synchronous motor is established, and its expression is as follows:

[0121]

[0122] In the formula, R s is the stator resistance, u d 、u q is the dq axis stator voltage; i d 、i q is the dq axis stator current, ψ f is the stator flux, L d , L q is the dq axis inductance, T e is the load torque, P n is the pole pair number, ω e is the electrical angular velocity of the motor rotor;

[0123] Based on the voltage equation, the stator current equation in the rotating coordinate system dq is obtained:

[0124]

[0125] The stator current equation is discretized by first-order forward difference to obtain the discretized current equation:

[0126]

[0127] In the formula, i d(k+1) ,i q(k+1) are the predicted values ​​of the d-axis and q-axis stator current components at time k+1, u d(k) 、u q(k)is the d-axis and q-axis stator voltage at time k, i d(k) ,i q(k) are the components of the d-axis and q-axis stator currents at time k, ω e(k) is the electrical angular velocity of the motor rotor at time k;

[0128] For surface mounted permanent magnet synchronous motors, L d =L q , transform the torque equation and get the new torque equation:

[0129]

[0130] Based on the new torque equation and the discretized current equation, the torque flux prediction formula of the permanent magnet synchronous motor is established, and its expression is as follows:

[0131]

[0132] Where, T e (k+1),ψ s (k+1) are the predicted values ​​of electromagnetic torque and stator flux at time k+1, ψ d (k+1),ψ q (k+1) are the predicted values ​​of the d-axis and q-axis stator flux components at time k+1;

[0133] Using the torque flux prediction formula, the stator flux angle change θ is calculated f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1).

[0134] In this embodiment: using the pre-built space voltage vector optimization model, the stator flux angle variation, electromagnetic torque and stator flux are processed to obtain the space voltage optimization vector as follows:

[0135] The cost function is designed based on the minimum torque ripple principle, and the electromagnetic torque and stator flux are used as evaluation indicators of the controller performance to predict the controlled variable F at time k+1. The calculation formula is as follows:

[0136]

[0137] in and are the reference values ​​of torque and flux respectively; coefficient Q is the weight coefficient, T e is the electromagnetic torque, ψ s is the stator flux, k is the kth moment;

[0138] A new type of space voltage vector switch table is set to select two optimal space voltage vectors, namely, space voltage optimization vectors. The input of the new type of space voltage vector switch table is the sector where the stator flux vector is located and the torque. U1 to U6 represent six space voltage vectors, S1 to S6 represent sectors 1 to 6, ΔT>0 represents increasing torque, and ΔT<0 represents decreasing torque.

[0139] When considering the torque performance, four space voltage vectors for clockwise and counterclockwise rotation directions are selected; for the stator flux performance, it is already included in the minimum value of the cost function;

[0140] According to the stator flux angle change θ f and torque offset ΔT e Select the space voltage optimization vector, and its calculation formula is as follows:

[0141]

[0142] In the formula, ψ α and ψ β are the stator flux components of α and β axes respectively;

[0143] The principle of selecting two spatial voltage optimization vectors depends on the stator flux θ f and torque offset T e , when a zero space voltage vector U0 does not provide a zero torque offset; to reduce switching losses, only one bridge arm is changed, and switching transitions are reduced by applying U0 and U7.

[0144] In this embodiment, the method of processing the spatial voltage optimization vector by using the pre-built switching time calculation model to obtain the switching time is as follows:

[0145] According to the torque performance linearization characteristics, the torque size at k+1 is predicted; a virtual space voltage vector is applied to the on-time t of the duty cycle on , a zero-space voltage vector is applied to control the duty cycle at the cut-off time t off ; The calculation formula of the torque at k+1 is as follows:

[0146]

[0147] Where l1 and l2 are the torque differential coefficients of the virtual space voltage vector and the zero space voltage vector respectively; the average torque control has a function that keeps the torque within the torque inertia delay δT bandwidth, and its calculation formula is as follows:

[0148]

[0149] By solving the stator flux angle change θ fCalculate the torque offset ΔT using the formula e Indicates the switching time t on ;

[0150] The switching time t is calculated by using the spatial voltage vector, current, stator flux position and electric rotor position. on ;

[0151] Applying the virtual space voltage vector, the switching time, i.e. the switching time, is obtained. The switching time calculation formula is as follows:

[0152]

[0153] The cut-off time t of the zero-space voltage vector control duty cycle is off The calculation formula is as follows:

[0154] t off =T s -t on (15).

[0155] In this embodiment: Based on the pre-built cost function minimization model, the switching time is processed to obtain the method of the space voltage vector as follows:

[0156] Firstly, the vector selection and space voltage vector and cost function optimization are performed, and then the cost function is evaluated;

[0157] Due to the adoption of average torque control, the calculation time is reduced without affecting the torque performance;

[0158] A virtual space voltage vector and a zero space voltage vector are operated in each sampling time, and the output of the switching time and speed PI controller is and reference value of magnetic linkage After processing, the space voltage vector S is obtained A , S B and S C .

[0159] In this embodiment: through the pre-built three-phase inverter control model, according to the space voltage vector, the switching action information of the switch tube is obtained, which is used to control the bus voltage input to the permanent magnet synchronous motor, and the method for driving the permanent magnet synchronous motor is as follows:

[0160] A three-phase inverter is provided, which is a typical two-level three-phase voltage source inverter, consisting of three upper and lower bridge arms, which includes six switching devices;

[0161] The space voltage vector S A , S B and S CIt is applied to the six switch devices respectively, and the six switch tubes are switched to control the bus voltage U dc Input to permanent magnet synchronous motor;

[0162] When an upper bridge arm switch device is turned on, the bus voltage is applied to the motor stator winding from the upper bridge arm switch device; through a series of on-off combinations, the bus voltage is regularly applied to the motor, thereby driving the motor and realizing the driving of the permanent magnet synchronous motor.

[0163] A second specific embodiment of the method for direct torque control of a permanent magnet synchronous motor based on model prediction of the present invention:

[0164] The method for direct torque control of a permanent magnet synchronous motor based on model prediction comprises the following steps:

[0165] Step 1: collect the two-phase current (i a 、i b and i c );

[0166] Step 2: Using the pre-built Clarke transformation model, the collected two-phase current (i a 、i b and i c ) is processed to obtain the conversion current i α (k) and i β (k);

[0167] Step 3: Use the pre-built flux and torque model to transform the current i α (k) and i β (k) is processed to obtain the stator flux angle change θ f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1);

[0168] Step 4: Use the pre-built space voltage vector optimization model to calculate the stator flux angle change θ f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1) is processed to obtain the spatial voltage optimization vector U f1,f2,f3,f4,f5,f6 ;

[0169] Step 5: Use the pre-built switching time calculation model to process the spatial voltage optimization vector, current, stator flux position, and electric rotor position to obtain the switching time t on1,on2,on3,on4,on5,on6 ;

[0170] Step 6: Minimize the output of the switching time and speed PI controller based on the pre-built cost function model and reference value of magnetic linkage After processing, the space voltage vector S is obtained A , S B and S C ;

[0171] Step 7: Based on the pre-built three-phase inverter control model, the space voltage vector S A , S B and S C , get the switch action information of the switch tube, which is used to control the bus voltage U dc The input is then fed into the permanent magnet synchronous motor to drive the permanent magnet synchronous motor.

[0172] like Figure 1 As shown, a specific embodiment of the direct torque control system of a permanent magnet synchronous motor based on model prediction of the present invention is as follows:

[0173] A direct torque control system of a permanent magnet synchronous motor based on model prediction includes the following contents:

[0174] The two-phase current (i) of the permanent magnet synchronous motor (PMSM) is collected by using a two-phase Hall current sensor sampling method. a 、i b and i c ) is used as the input of the Clarke transform module, and the output of the Clarke transform module (i α (k) and i β (k)) are used as the input of the flux and torque prediction control module based on space voltage vector and cost function optimization and the sliding mode observer respectively; the space voltage vector S of the permanent magnet synchronous motor (PMSM) is obtained by using the flux and torque prediction control module based on space voltage vector and cost function optimization. A , S B and S C As the input of the inverter, the input of the first subtractor is the given speed n * (k) and the output n(k) of the sliding mode observer, the output Δn of the first subtractor is obtained * (k).

[0175] like Figure 2 As shown, the third specific embodiment of the method for direct torque control of a permanent magnet synchronous motor based on model prediction of the present invention is as follows:

[0176] The method of direct torque control of permanent magnet synchronous motor based on model prediction includes the following contents:

[0177] The output Δn of the first subtractor * (k) is connected to the input of the speed PI controller, and the output of the Clarke transformation model (i α(k) and i β (k)) is used as the input of the flux linkage and torque model prediction. The outputs of the flux linkage and torque model prediction are the stator flux angle change θ f 、T e (k+1) and ψ s (k+1), the input of the space voltage vector optimization model is the stator flux angle change θ f , the output is U f1,f2,f3,f4,f5,f6 , as the input of the cost function minimization model are the output of the speed PI controller and reference value of magnetic linkage And the output of the switching time calculation model t on1,on2,on3,on4,on5,on6 The outputs of the cost function minimization model are the spatial voltage vector S A , S B and S C . It specifically includes the following steps:

[0178] Step 1: Clarke transformation model, including the following:

[0179] The two-phase current i of the permanent magnet synchronous motor in the three-phase coordinate system a and i b It is obtained by collecting current signals through two Hall current sensors and input into the Clarke transformation model. The transformation formula of the Clarke transformation model is:

[0180]

[0181] Among them, the phase current i c Through the formula i a +i b +i c =0 calculated;

[0182] The output of the Clarke transformation model (i α (k) and i β (k)) are used as the input of the predictive torque model and the sliding mode observer, respectively.

[0183] Step 2: The flux linkage and torque model prediction model includes the following:

[0184] The voltage equation of the permanent magnet synchronous motor in the rotating coordinate system (dq) is as follows:

[0185]

[0186] The torque equation of the permanent magnet synchronous motor is as follows:

[0187]

[0188] In the formula, Rs is the stator resistance, u d 、u q is the dq axis stator voltage. d 、i q is the dq axis stator current, ψ f is the stator flux, L d , L q is the dq axis inductance, T e is the load torque, p is the number of pole pairs, ω e is the electrical angular velocity of the motor rotor.

[0189] The stator current equation in the rotating coordinate system (dq) is obtained:

[0190]

[0191] The discretization process is performed by first-order forward difference.

[0192]

[0193] For surface mounted permanent magnet synchronous motors, L d =L q , the torque equation is:

[0194]

[0195] The torque flux prediction model of permanent magnet synchronous motor is:

[0196]

[0197] In the formula, ψ d (k+1),ψ q (k+1)T s The predicted value of the dq-axis stator flux component at time T e (k+1),ψ s (k+1)T s Predicted values ​​of electromagnetic torque and stator flux at time .

[0198] The speed loop is controlled by a proportional-integral (PI) controller. Proportional adjustment immediately reduces the deviation when the error occurs. The proportional coefficient can speed up the response and reduce the error. However, too large a coefficient will reduce the stability of the system. The integral controller eliminates the steady-state error and improves the error-free degree of the system.

[0199] Step 3: Space voltage vector optimization model, including the following contents:

[0200] The cost function is designed based on the principle of minimum torque ripple, and torque and flux are used as evaluation indicators of controller performance. Predict the controlled variable at time (k+1) from the discrete model

[0201]

[0202] in and are the reference values ​​of torque and flux, respectively. Coefficient Q is the weight coefficient, T e is the electromagnetic torque, ψ s is the stator flux, and k is the kth moment. It plays an important role in high-performance motor drive systems using MPTC. In traditional MPTC, all possible space voltage vectors are replaced by (7) to obtain the optimal space voltage vector, but the calculation burden is increased. In order to reduce the amount of calculation, a new switch table is proposed, as shown in Table 1.

[0203] Table 1 Space voltage vector new switch table

[0204]

[0205] Two optimal space voltage vectors will be selected from the table at the same time. The input of the new switch table of space voltage vector is the sector where the stator flux vector is located and the torque. In the table, U1~U6 represent 6 space voltage vectors, S1~S6 represent sectors 1~6, ΔT>0 represents increasing torque, and ΔT<0 represents reducing torque.

[0206] When considering the torque performance, it is necessary to select the 4 possible space voltage vectors for clockwise and counterclockwise rotation directions. For the stator flux performance, it is already included in the minimum value of the cost function. According to the stator flux angle change θ f and torque offset ΔT e Selecting the space voltage vector

[0207]

[0208] The principle of choosing two possible space voltage vectors depends on the stator flux θ f and torque offset T e , as shown in Table 1. In Table 1, because a zero space voltage vector U0 does not provide a zero torque offset. In order to reduce switching losses, only one bridge arm is changed, and the switching transition is reduced by applying U0 and U7.

[0209] Step 4: Switching time calculation model, including the following:

[0210] The permanent magnet synchronous motor model predictive torque control method based on space voltage vector and cost function optimization of the present invention uses a virtual space voltage vector (AVSV) and a zero space voltage vector (ZVSV) in each control cycle. Due to the influence of torque inertia delay, average torque control has an advantage in predicting the torque of the permanent magnet synchronous motor. Therefore, the duty cycle of the virtual space voltage vector is obtained by using the average torque control principle. The average torque control principle is as follows Figure 3 As shown in Figure 2, the torque performance can be assumed to be linear and the torque at (k+1) can be predicted. A virtual space voltage vector is applied to the on-time t of the duty cycle. on , a zero-space voltage vector is applied to control the duty cycle at the cut-off time t off The torque at (k+1) can be predicted as

[0211]

[0212] Where l1 and l2 are the torque differential coefficients of the virtual space voltage vector and the zero space voltage vector, respectively. The average torque control has a function that keeps the torque within the torque inertia delay δT bandwidth, which can be calculated as

[0213]

[0214] By solving equation (10), the switching time t can be expressed by equation (11): on The switching time t can be calculated from the spatial voltage vector, current, stator flux position and rotor position on Therefore, the switching time of applying the virtual space voltage vector is

[0215]

[0216] The cut-off time t of the zero-space voltage vector control duty cycle is off It can be calculated as

[0217] t off =T s -t on (15)

[0218] Step 5: Cost function minimization model, including the following:

[0219] In the permanent magnet synchronous motor model predictive torque control method based on space voltage vector and cost function optimization of the present invention, vector selection and space voltage vector and cost function optimization are first performed, and then the cost function is evaluated. Instead of evaluating all possible space voltage vectors, MPTC only selects three possible space voltage vectors in Table 1. Due to the use of average torque control, the calculation time is reduced and the torque performance is not affected. The switching time of each of the three possible space voltage vectors is calculated by formula (14), and the variables in (k+1) are predicted.

[0220] According to the application of the proposed MPTC, a virtual space voltage vector and a zero space voltage vector are operated in each sampling time. However, the proposed control scheme can ensure that the switching time t on reaches a maximum value (less than the sampling time). Therefore, the switching time remains constant, thus reducing the switching cost.

[0221] Step 6: The three-phase inverter generates a space voltage vector S according to the output of step 5. A , S B and S C The six switch tubes are switched to control the bus voltage U dc The three-phase inverter in the present invention is a typical two-level three-phase voltage source inverter, which consists of three upper and lower bridge arms (six switching devices). The cost function minimizes the spatial voltage vector S output by the model. A , S B and S C That is, it is applied to the six switch devices respectively. When a certain upper bridge arm switch device is turned on, the bus voltage is applied to the motor stator winding from the upper bridge arm switch device. Through a series of on-off combinations, the bus voltage is regularly applied to the motor, thereby driving the motor.

[0222] An embodiment of a device applying the method of the present invention:

[0223] An electronic device comprising:

[0224] one or more processors;

[0225] A storage device for storing one or more programs;

[0226] When the one or more programs are executed by the one or more processors, the one or more processors implement the above-mentioned permanent magnet synchronous motor direct torque control method based on model prediction.

[0227] A computer medium embodiment using the method of the present invention:

[0228] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the above-mentioned permanent magnet synchronous motor direct torque control method based on model prediction.

[0229] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, and computer program products. Therefore, the present application may take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, optical storage, etc.) containing computer-usable program codes.

[0230] The present application is described by flowcharts or / and block diagrams of the methods, devices (systems), and computer program products of the embodiments of the present application. It should be understood that each process or / and block in the flowchart or / and block diagram and the combination of the processes or / and blocks in the flowchart or / and block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart or / and block diagram. Figure 1 Process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0231] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 Process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.

[0232] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 Process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0233] The model in this application is an object that objectively describes the morphological structure with the help of physical or virtual representation. The object is not equal to the object and is not limited to physical and virtual. It can be a data processing function, software program, processing mode, usage method, operation method, workflow, application process, electronic hardware, circuit model, processing system, system imitation or simulation object.

[0234] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field can still modify or replace the specific implementation methods of the present invention with equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for direct torque control of a permanent magnet synchronous motor based on model prediction, characterized in that: Includes the following: The pre-built Clarke transformation model is used to process the collected two-phase currents of the permanent magnet synchronous motor to obtain the transformation current; The pre-built flux and torque model is used to process the conversion current to obtain the stator flux angle change, electromagnetic torque and stator flux; Using the pre-built space voltage vector optimization model, the stator flux angle change, electromagnetic torque and stator flux are processed to obtain the space voltage optimization vector; Using the pre-built switching time calculation model, the spatial voltage optimization vector is processed to obtain the switching time; Based on the pre-built cost function minimization model, the switching time is processed to obtain the spatial voltage vector; Through the pre-built three-phase inverter control model, the switching action information of the switch tube is obtained according to the space voltage vector, which is used to control the bus voltage input to the permanent magnet synchronous motor, realize the drive of the permanent magnet synchronous motor, and complete the direct torque control of the permanent magnet synchronous motor based on model prediction.

2. The method for direct torque control of a permanent magnet synchronous motor based on model prediction according to claim 1, characterized in that: The method of processing the collected two-phase current of the permanent magnet synchronous motor by using the pre-built Clarke transformation model to obtain the transformation current is as follows: The two-phase current i of the permanent magnet synchronous motor in the three-phase coordinate system is obtained by collecting current signals with two Hall current sensors. a and i b ; The transformation formula of the Clarke transformation model is constructed as follows: Among them, the phase current i c Through the formula i a +i b +i c =0 calculated; Based on the transformation formula, the two-phase current i a and i b Calculate and obtain the conversion current (i α (k) and i β (k)).

3. The method for direct torque control of a permanent magnet synchronous motor based on model prediction according to claim 1, characterized in that: The method of processing the conversion current using the pre-built flux and torque model to obtain the stator flux angle change, electromagnetic torque and stator flux is as follows: The voltage equation of the permanent magnet synchronous motor in the rotating coordinate system dq is established, and its expression is as follows: The torque equation of the permanent magnet synchronous motor is established, and its expression is as follows: In the formula, R s is the stator resistance, u d 、u q is the dq axis stator voltage, i d 、i q is the dq axis stator current, ψ f is the stator flux, L d , L q is the dq axis inductance, T e is the load torque, P n is the pole pair number, ω e is the electrical angular velocity of the motor rotor; Based on the voltage equation, the stator current equation in the rotating coordinate system dq is obtained: The stator current equation is discretized by first-order forward difference to obtain the discretized current equation: In the formula, i d(k+1) ,i q(k+1) are the predicted values ​​of the d-axis and q-axis stator current components at time k+1, u d(k) 、u q(k) is the d-axis and q-axis stator voltage at time k, i d(k) ,i q(k) are the components of the d-axis and q-axis stator currents at time k, ω e(k) is the electrical angular velocity of the motor rotor at time k; For surface mounted permanent magnet synchronous motors, L d =L q , transform the torque equation and get the new torque equation: Based on the new torque equation and the discretized current equation, the torque flux prediction formula of the permanent magnet synchronous motor is established, and its expression is as follows: Where, T e (k+1),ψ s (k+1) are the predicted values ​​of electromagnetic torque and stator flux at time k+1, ψ d (k+1),ψ q (k+1) are the predicted values ​​of the d-axis and q-axis stator flux components at time k+1; Using the torque flux prediction formula, the stator flux angle change θ is calculated f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1).

4. The method for direct torque control of a permanent magnet synchronous motor based on model prediction according to claim 1, characterized in that: Using the pre-built space voltage vector optimization model, the stator flux angle change, electromagnetic torque and stator flux are processed to obtain the space voltage optimization vector as follows: The cost function is designed based on the minimum torque ripple principle, and the electromagnetic torque and stator flux are used as evaluation indicators of the controller performance to predict the controlled variable F at time k+1. The calculation formula is as follows: in and are the reference values ​​of torque and flux respectively; The coefficient Q is the weight coefficient, T e is the electromagnetic torque, ψ s is the stator flux, k is the kth moment; A new type of space voltage vector switch table is set to select two optimal space voltage vectors, namely, space voltage optimization vectors. The input of the new type of space voltage vector switch table is the sector where the stator flux vector is located and the torque. U1 to U6 represent six space voltage vectors, S1 to S6 represent sectors 1 to 6, ΔT>0 represents increasing torque, and ΔT<0 represents decreasing torque. When considering the torque performance, four space voltage vectors for clockwise and counterclockwise rotation directions are selected; for the stator flux performance, it is already included in the minimum value of the cost function; According to the stator flux angle change θ f and torque offset ΔT e Select the space voltage optimization vector, and its calculation formula is as follows: In the formula, ψ α and ψ β are the stator flux components of α and β axes respectively; The principle of selecting two spatial voltage optimization vectors depends on the stator flux θ f and torque offset T e .

5. The method for direct torque control of a permanent magnet synchronous motor based on model prediction according to claim 1, characterized in that: The method of processing the spatial voltage optimization vector using the pre-built switching time calculation model to obtain the switching time is as follows: According to the torque performance linearization characteristics, the torque size at k+1 is predicted; a virtual space voltage vector is applied to the opening time t of the duty cycle on , a zero-space voltage vector is applied to control the duty cycle at the cut-off time t off ; The calculation formula of the torque at k+1 is as follows: Among them, l1 and l2 are the torque differential coefficients of the virtual space voltage vector and the zero space voltage vector respectively; the average torque control has a function that keeps the torque within the torque inertia delay δT bandwidth, and its calculation formula is as follows: By solving the stator flux angle change θ f Calculate the torque offset ΔT using the formula e Indicates the switching time t on ; The switching time t is calculated by using the spatial voltage vector, current, stator flux position and electric rotor position. on ; Applying the virtual space voltage vector, the switching time, i.e. the switching time, is obtained. The switching time calculation formula is as follows: The cut-off time t of the zero-space voltage vector control duty cycle is off The calculation formula is as follows: t off =T s -t on 。 6. The method for direct torque control of a permanent magnet synchronous motor based on model prediction according to claim 1, characterized in that: Based on the pre-built cost function minimization model, the switching time is processed to obtain the space voltage vector as follows: Firstly, the vector selection and space voltage vector and cost function optimization are performed, and then the cost function is evaluated; Due to the adoption of average torque control, the calculation time is reduced without affecting the torque performance; The switching time of each of the three space voltage vectors is calculated using the switching time calculation formula, and the variables in (k+1) are predicted; A virtual space voltage vector and a zero space voltage vector are operated in each sampling time, and the output of the switching time and speed PI controller is and reference value of magnetic linkage After processing, the space voltage vector S is obtained A , S B and S C .

7. The method for direct torque control of a permanent magnet synchronous motor based on model prediction according to claim 1, characterized in that: Through the pre-built three-phase inverter control model, according to the space voltage vector, the switching action information of the switch tube is obtained to control the bus voltage input to the permanent magnet synchronous motor. The method for driving the permanent magnet synchronous motor is as follows: A three-phase inverter is provided, which is a typical two-level three-phase voltage source inverter, consisting of three upper and lower bridge arms, which includes six switching devices; The space voltage vector S A , S B and S C It is applied to the six switch devices respectively, and the six switch tubes are switched to control the bus voltage U dc Input to permanent magnet synchronous motor; When an upper bridge arm switch device is turned on, the bus voltage is applied to the motor stator winding from the upper bridge arm switch device; through a series of on-off combinations, the bus voltage is regularly applied to the motor, thereby driving the motor and realizing the driving of the permanent magnet synchronous motor.

8. A method for direct torque control of a permanent magnet synchronous motor based on model prediction, characterized in that: The following steps are involved: Step 1: collect the two-phase current (i a 、i b and i c ); Step 2: Using the pre-built Clarke transformation model, the collected two-phase current (i a 、i b and i c ) is processed to obtain the conversion current i α (k) and i β (k); Step 3: Use the pre-built flux and torque model to transform the current i α (k) and i β (k) is processed to obtain the stator flux angle change θ f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1); Step 4: Use the pre-built space voltage vector optimization model to calculate the stator flux angle change θ f , electromagnetic torque T e (k+1) and stator flux ψ s (k+1) is processed to obtain the spatial voltage optimization vector U f1,f2,f3,f4,f5,f6 ; Step 5: Use the pre-built switching time calculation model to process the spatial voltage optimization vector, current, stator flux position, and electric rotor position to obtain the switching time t on1,on2,on3,on4,on5,on6 ; Step 6: Minimize the output of the switching time and speed PI controller based on the pre-built cost function model and reference value of magnetic linkage After processing, the space voltage vector S is obtained A , S B and S C ; Step 7: Based on the pre-built three-phase inverter control model, the space voltage vector S A , S B and S C , get the switch action information of the switch tube, which is used to control the bus voltage U dc The input is then fed into the permanent magnet synchronous motor to drive the permanent magnet synchronous motor.

9. A direct torque control system for a permanent magnet synchronous motor based on model prediction, characterized in that: It includes a permanent magnet synchronous motor, a two-phase Hall current sensor, a Clarke transformation module, a flux linkage and torque prediction control module, a sliding mode observer, an inverter and a first subtractor: The two-phase current i of the permanent magnet synchronous motor is collected by using the two-phase Hall current sensor sampling method. a 、i b and i c As the input of the Clarke transform module, the output of the Clarke transform module i α (k) and i β (k) are used as the input of the flux and torque prediction control module and the sliding mode observer respectively; the spatial voltage vector S of the permanent magnet synchronous motor PMSM is obtained by using the flux and torque prediction control module. A , S B and S C As the input of the inverter, the input of the first subtractor is the given speed n * (k) and the output n(k) of the sliding mode observer, thereby obtaining the output Δn of the first subtractor * (k).

10. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the program is executed by a processor, the method for direct torque control of a permanent magnet synchronous motor based on model prediction as described in any one of claims 1 to 9 is implemented.

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