A method and system for permanent magnet synchronous motor speed regulation design

Abstract

The application relates to a permanent magnet synchronous motor speed regulation design method and system, wherein the method comprises the following steps: S1, constructing a mathematical model of a permanent magnet synchronous motor; S2, constructing a new reaching law, and designing a sliding mode controller according to the new reaching law and the mathematical model of the permanent magnet synchronous motor; S3, designing a disturbance observer; S4, observing the load disturbance of the permanent magnet synchronous motor through the disturbance observer, and compensating the observation value to the sliding mode controller, so as to complete the speed regulation of the permanent magnet synchronous motor. The application solves the problems of speed fluctuation and instability when the permanent magnet synchronous motor suddenly joins a load.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet synchronous motor control technology, and in particular to a speed regulation design method and system for permanent magnet synchronous motors. Background Technology

[0002] Permanent magnet synchronous motors (PMSMs) are widely used in wind power generation, aerospace, and high-precision machine tools due to their advantages such as high torque density, high precision, high speed, and low losses. PI control algorithms are widely used in motor speed loop controllers because of their relative simplicity and high reliability. However, high-precision machine tools place high demands on motor performance. When uncertainties such as nonlinear friction, parameter variations, and load disturbances affect system control performance, traditional PI control struggles to meet these requirements. To address these issues, many advanced control methods have been applied to PMSMs, such as sliding mode control, predictive control, and adaptive control.

[0003] Sliding Mode Control (SMC) is a widely recognized and applied control method due to its fast response, strong robustness, and high disturbance rejection capability. SMC places the system in a sliding mode, which is less sensitive to changes in system parameters and external disturbances, thus enhancing the system's robustness. However, due to the characteristics of the sliding mode, chattering is unavoidable in SMC, which reduces the system's tracking accuracy and dynamic performance. Furthermore, generally, adjusting the sliding mode parameters to increase the approach speed often simultaneously increases the system's overshoot and chattering. Therefore, the key to SMC is to achieve high approach speed while reducing overshoot and chattering.

[0004] The concept of reaching speed was proposed by Professor Gao Weibing in my country. Improving the reaching speed is the most common method for suppressing chattering in sliding mode. Professor Gao proposed the constant velocity reaching speed law, the power reaching speed law, and the exponential reaching speed law, which are of great significance to the field of sliding mode. Building on this, in order to further improve the reaching speed and eliminate chattering, scholars have developed various new reaching speed laws. Tong Kewen et al. used a variable exponential reaching speed law to reduce chattering on the sliding surface; however, the ability of this reaching speed law to eliminate chattering is time-dependent, and its robustness is not strong enough. Some literature has also proposed using mathematical relationships to improve the performance of sliding mode. For example, Rohith G proposed a fractional power reaching speed law, which improved the system's response speed and reduced chattering; Zhang Xiaoguang et al. used terminal attractors to change the reaching speed law, improving the system's performance. However, this method places excessive demands on the system parameters; Tian et al. designed a variable exponential reaching law, which achieved an adaptive effect, but in practical applications, singularities are easily generated in the initial state; Zhang Yao et al. adopted a multi-power reaching law, which further improved the system's reaching speed; Lin Jieqiong et al. proposed an improved double-power exponential reaching law, which divides the system's arrival at the sliding surface into two stages. This method can reduce chattering and track the desired trajectory faster, ensuring the dynamic quality of the system, but the mathematical model is relatively complex.

[0005] In practical applications, because load torque is unmeasurable, its estimation and compensation are crucial to the performance of speed control systems. YANG et al. summarized various disturbance estimation methods, and the most common and efficient way to estimate load disturbances is to add an observer to the system. Liu Ying et al. used an observer to estimate load disturbances and then used the observation results to feedforward compensate the system, thereby improving the system's disturbance rejection and reducing chattering. Dan Ning et al. used a fast twist algorithm combined with a disturbance observer for composite control to suppress chattering in sliding mode. Wang Xiang et al. proposed an adaptive discrete terminal sliding mode control method based on an extended state observer, which classifies uncertain disturbances in the dynamic model into lumped disturbances and then uses an extended state observer to observe and compensate for them. This method improves torque... The system exhibits strong robustness against disturbances. Li Zheng et al. adopted integral sliding mode control and combined it with a load torque observer to improve the speed regulation performance of the system. ZHANG et al. improved the sliding mode exponential approach law and combined it with a disturbance observer to compensate for the reference voltage changes caused by motor parameter disturbances, thereby enhancing the robustness of the system. Hou Limin et al. adopted a method combining active disturbance rejection control structure with sliding mode control, and optimized the extended state observer and nonlinear error feedback control law in active disturbance rejection using a sliding mode algorithm. Bai Tianyu et al. adopted a sliding mode observer and designed a new sliding surface to reduce high-frequency harmonics and effectively solve problems such as low speed estimation accuracy and large jitter. Summary of the Invention

[0006] Therefore, the technical problem to be solved by the present invention is to overcome the speed fluctuation and instability problems of permanent magnet synchronous motors when a load is suddenly added in the prior art.

[0007] To solve the above-mentioned technical problems, the present invention provides a speed control design method for a permanent magnet synchronous motor, comprising:

[0008] Step S1: Construct a mathematical model of the permanent magnet synchronous motor;

[0009] Step S2: Construct the sliding surface and the new approach law, and design the sliding mode controller based on the sliding surface, the new approach law, and the mathematical model of the permanent magnet synchronous motor;

[0010] Step S3: Design a disturbance observer;

[0011] Step S4: The load disturbance of the permanent magnet synchronous motor is observed by the disturbance observer, and the observed value is compensated to the sliding mode controller to complete the speed regulation of the permanent magnet synchronous motor.

[0012] In one embodiment of the present invention, step S1: constructing a mathematical model of a permanent magnet synchronous motor, the method includes:

[0013] The torque equation for the permanent magnet synchronous motor is constructed as follows:

[0014] T E =1.5p * ψ f i q (2)

[0015] The equations of motion for the permanent magnet synchronous motor are as follows:

[0016]

[0017] In the formula, i q The stator current q-axis component is represented by w; the actual motor speed is represented by p. * ψ is the number of pole pairs of the motor; f For permanent magnets and stator linkage; T E T is the electromagnetic torque. L J is the load torque; J is the moment of inertia.

[0018] Combining equations (2) and (3), we obtain the mathematical model of the permanent magnet synchronous motor:

[0019]

[0020] In one embodiment of the present invention, the new approach law in step S2 is constructed based on the inverse trigonometric function and the exponential function.

[0021] In one embodiment of the present invention, step S2 involves constructing a new reaching law and designing a sliding mode controller based on the new reaching law and the mathematical model of the permanent magnet synchronous motor. The method includes:

[0022] The formula for constructing the sliding surface of the sliding mode controller is as follows:

[0023]

[0024] In the formula, c > 0, p < q, and p and q are positive odd numbers;

[0025] A new reaching law for the sliding mode controller is constructed, with the following formula:

[0026]

[0027] In the formula, k1,k2>0, and a,b are adjustable parameters;

[0028] Let the error e be the difference between the desired motor speed and the actual motor speed, and then differentiate it to obtain:

[0029]

[0030] In the formula, w * Given the motor speed, w is the actual motor speed;

[0031] Substituting the error e into x in the sliding surface of equation (5), we obtain equation (8) and then differentiate it:

[0032]

[0033] Substituting equation (7) into equation (8), we get:

[0034]

[0035] Substituting equations (4) and (6) into equation (9), we obtain the sliding mode controller for the permanent magnet synchronous motor:

[0036]

[0037] In the formula, This is an estimate of the load disturbance.

[0038] In one embodiment of the present invention, the stability of the sliding mode controller is analyzed by means of:

[0039] Selecting Lyapunov functions:

[0040] Differentiating equation (12) and combining it with equation (6), we get:

[0041]

[0042] In the formula, k1,k2>0, and s 2 >0, |ae| b|s| >0, arctan(s)·s>0, therefore we can obtain According to the Lyapunov stability criterion, the sliding mode controller tends to stabilize.

[0043] In one embodiment of the present invention, the method for designing the disturbance observer in step S3 includes:

[0044] Using motor speed and load torque as state variables, the state equation of equation (14) is constructed as follows:

[0045]

[0046] In the formula, z1 and z2 represent w and T respectively. L ;

[0047] Let the coefficient matrix of equation (14) be:

[0048]

[0049] Let the output error feedback matrix L of the disturbance observer be:

[0050]

[0051] In the formula, l1 and l2 are constant values ​​of the error feedback parameters;

[0052] The coefficient matrix of the perturbation observer is then:

[0053]

[0054] To obtain the feedback matrix L in the disturbance observer, it is necessary to presuppose that the eigenvalues ​​of A-LC have negative real parts, and construct equation (18) according to equation (14)-equation (17). Then equation (18) is the final disturbance observer equation.

[0055]

[0056] In one embodiment of the present invention, the control law of the permanent magnet synchronous motor is obtained by rearranging equation (10):

[0057]

[0058] To solve the above-mentioned technical problems, the present invention provides a speed control design system for a permanent magnet synchronous motor, comprising:

[0059] First building block: Used to build the mathematical model of the permanent magnet synchronous motor;

[0060] The second construction module is used to construct the sliding surface and the new approach law, and to design the sliding controller based on the sliding surface, the new approach law and the mathematical model of the permanent magnet synchronous motor.

[0061] Design module: Used for designing disturbance observers;

[0062] Speed ​​control module: used to observe the load disturbance of the permanent magnet synchronous motor through the disturbance observer, and compensate the observed value to the sliding mode controller to complete the speed control of the permanent magnet synchronous motor.

[0063] To solve the above-mentioned technical problems, the present invention provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the speed control design method for permanent magnet synchronous motors described above.

[0064] To solve the above-mentioned technical problems, the present invention provides a computer-readable storage medium having a computer program stored thereon, wherein when the computer program is executed by a processor, the steps of the speed control design method for permanent magnet synchronous motors described above are implemented.

[0065] The technical solution of the present invention has the following advantages over the prior art:

[0066] This invention designs a novel approach law for the control system of permanent magnet synchronous motor. This approach law can change the approach speed according to different convergence stages, so that the sliding mode variable increases the approach speed when it is far away from the sliding surface, and suppresses chattering and overshoot when it is close to the sliding surface, thereby obtaining good control performance. In addition, this approach law also has the advantages of simple mathematical model and convenient parameter adjustment.

[0067] This invention introduces a disturbance observer (Lumberjack observer) to observe the load disturbance of the permanent magnet synchronous motor and compensates the observed value into the sliding mode controller, thereby further improving the robustness of the system;

[0068] Simulation experiments show that the control method of the present invention can effectively improve the system response speed, suppress chattering and overshoot, and reduce the influence of external disturbances, exhibiting good robustness. Attached Figure Description

[0069] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0070] Figure 1 This is a flowchart of the method of the present invention;

[0071] Figure 2 This is a schematic diagram comparing the graphs of the arctan function and the sgn function in an embodiment of the present invention;

[0072] Figure 3 This is a simulation diagram of the disturbance observer's observation of the load torque in an embodiment of the present invention;

[0073] Figure 4 This is an overall structural block diagram of the PMSM speed control system in an embodiment of the present invention;

[0074] Figure 5 This is a comparison diagram of the initial rotational speed response under two approach laws in an embodiment of the present invention;

[0075] Figure 6 This is a comparison diagram of the stability of the two reaching laws after adding load perturbation in the embodiments of the present invention;

[0076] Figure 7 This is a comparison diagram of the rotational speed after the load is eliminated by the two control methods in the embodiments of the present invention. Detailed Implementation

[0077] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments described are not intended to limit the present invention.

[0078] Example 1

[0079] Reference Figure 1 As shown, this invention relates to a speed control design method for a permanent magnet synchronous motor, comprising:

[0080] Step S1: Construct a mathematical model of the permanent magnet synchronous motor;

[0081] Step S2: Construct the sliding surface and the new approach law, and design the sliding mode controller based on the sliding surface, the new approach law, and the mathematical model of the permanent magnet synchronous motor;

[0082] Step S3: Design a disturbance observer;

[0083] Step S4: The load disturbance of the permanent magnet synchronous motor is observed by the disturbance observer, and the observed value is compensated to the sliding mode controller to complete the speed regulation of the permanent magnet synchronous motor.

[0084] This invention designs a novel reaching law for permanent magnet synchronous motor control systems. This reaching law can change the reaching speed according to different convergence stages, so that the reaching speed increases when the sliding mode variable is far away from the sliding surface, and suppresses chattering and overshoot when it is close to the sliding surface, thereby obtaining good control performance. In addition, the reaching law also has the advantages of simple mathematical model and convenient parameter tuning. This invention introduces a disturbance observer (Lumberjack observer) to observe load disturbances and compensate the observed values ​​into the sliding mode controller, further improving the robustness of the system.

[0085] The following is a detailed description of this embodiment:

[0086] This embodiment selects i d Since the vector control method is 0, the study is conducted in the dq coordinate system. The model of the permanent magnet synchronous motor in the dq coordinate system is as follows:

[0087]

[0088] There are several control methods for permanent magnet synchronous motors. Equation (1) in this embodiment is one of the control methods.

[0089] The torque equation for the permanent magnet synchronous motor is constructed as follows:

[0090] T E =1.5pψ f i q (2)

[0091] Without considering the coefficient of viscous friction, the motion equations of the permanent magnet synchronous motor are as follows:

[0092]

[0093] In the formula, i d i q The stator current consists of d-axis and q-axis components; u d u q R represents the d-axis and q-axis components of the stator voltage. s For stator resistance; L d L q The stator d-axis and q-axis inductances are represented by w; the actual motor speed is represented by p. * ψ is the number of pole pairs of the motor; f For permanent magnets and stator linkage; T E T is the electromagnetic torque. L is the load torque; J is the moment of inertia.

[0094] Combining equations (2) and (3), we obtain the mathematical model of the permanent magnet synchronous motor:

[0095]

[0096] 2. Sliding Mode Controller Design

[0097] The design of a sliding mode controller mainly consists of two stages: first, the design of the sliding surface; and second, the design of the reaching law. The design of the reaching law mainly addresses the process of the system approaching the sliding surface from infinity, while the design of the sliding surface addresses the process of approaching zero from the sliding surface.

[0098] The sliding surface, also called the switching function, determines the stability and dynamic performance of the sliding mode. Common sliding surfaces include linear sliding surfaces, integral sliding surfaces, terminal sliding surfaces, and higher-order sliding surfaces. This embodiment uses an integral terminal sliding surface. Compared with traditional sliding surfaces, the integral terminal sliding surface can converge in a finite time, and has the advantages of fast convergence speed and high robustness. Moreover, the integral terminal sliding surface has no second derivative after differentiation, resulting in strong simulation stability. Its basic form is:

[0099]

[0100] In equation (5), x represents the following errors e, c > 0, p < q, and p and q are positive odd numbers.

[0101] The reaching law initially referred to a condition for reaching a target in mathematics. Later, due to its good disturbance resistance and model independence, it was applied to control. To improve the quality of sliding mode motion and reduce chattering, this embodiment proposes a novel reaching law (6), which uses inverse trigonometric functions and power functions. Compared with the traditional linear reaching law, it has a stronger ability to adaptively adjust the reaching speed, and can adjust the reaching speed for different system states, thereby improving the robustness of the system.

[0102]

[0103] In the above reaching law, k1, k2 > 0, a, b are adjustable parameters, s is the sliding surface, and e is the error. When the system is far from the sliding surface, the system state variables e and s in the reaching law are relatively large. Due to the characteristics of the power-exponential function, |ae| b|s| It will become very large, at which point arctan(s) → π / 2. Thus, in the early stage of motor response or when subjected to disturbances, the larger approach law enables the system to obtain a larger approach speed.

[0104] When the system approaches stability, it is closer to the sliding surface, and the values ​​of e and s in the reaching law are relatively small. Therefore, the power-exponential function |ae| b|s| →0, arctan(s)→0, at this time If the value becomes very small, the approach speed will slow down, which can better reduce overshoot and alleviate system chattering.

[0105] The purpose of using the arctan function instead of the sgn sign function is twofold: firstly, to achieve a smooth transition of the system from a high-speed approaching state to an asymptotically stable state, aiming to reduce system overshoot and chattering; secondly, the maximum / minimum value of the arctan function is ±π / 2, while the maximum / minimum value of the sgn function is ±1, such as... Figure 1 As shown, the arctan function provides a larger adjustment margin.

[0106] In summary, the approaching law designed in this embodiment not only has a fast approaching speed, but also has small overshoot and chattering, which solves the drawback of some traditional approaching laws that cannot maintain their stability while improving the approaching speed.

[0107] Let the error e be the difference between the desired motor speed and the actual motor speed, and then differentiate it:

[0108]

[0109] Where w * Here, w represents the given rotational speed, and w represents the actual rotational speed.

[0110] Substituting the error e into x in equation (5), the sliding surface becomes equation (8), and the derivative is then obtained:

[0111]

[0112] Substituting equation (7) into equation (8), we get:

[0113]

[0114] Substituting equations (4) and (6) into equation (9), we obtain the sliding mode controller for the permanent magnet synchronous motor:

[0115]

[0116] The control law of the permanent magnet synchronous motor is obtained by rearranging equation (10):

[0117]

[0118] In the above formula The estimated value for the load disturbance will be presented in the next section on disturbance observer design.

[0119] To demonstrate the stability of the system, the Lyapunov function is chosen:

[0120]

[0121] According to the Lyapunov stability criterion, it is only necessary to prove... The asymptotic stability of the system can then be derived. Taking the derivative of equation (12) and combining it with equation (6), we get:

[0122]

[0123] In equation (13), k1, k2 > 0, and s 2 >0, |ae| b|s| >0, arctan(s)·s>0, therefore we can obtain Therefore, according to the Lyapunov stability criterion, this system tends to be stable.

[0124] 3. Design of the disturbance observer

[0125] To reduce the impact of load disturbances on control performance, this embodiment uses a Luneburger observer to estimate the load torque and compensate it into the sliding mode controller, thereby increasing the robustness of the system.

[0126] To ensure the observation accuracy of the state observer, this section derives the mathematical relationship between speed, motor torque and load torque, and uses speed and load torque as state variables to derive the state equation (14).

[0127]

[0128] In the formula, z1 and z2 represent w and T respectively. L ;

[0129] Let the coefficient matrix of equation (14) be:

[0130]

[0131] Let the output error feedback matrix L of the disturbance observer be:

[0132]

[0133] In the formula, l1 and l2 are constant values ​​of the error feedback parameters. Then the disturbance observer coefficient matrix is:

[0134]

[0135] According to modern control theory, to find the feedback matrix L in the observer, it is necessary to presuppose that the eigenvalues ​​of A-LC have negative real parts, and construct equation (18) according to equation (14)-equation (17). Then equation (18) is the final perturbation observer equation.

[0136]

[0137] It should be noted that since constructing the Romberg observer is existing technology, it will not be described in detail in this embodiment. l1 and l2 are obtained by the A-LC method of pre-setting the negative real part. For example, l1 = -5 / 2 * l2 is obtained. In this embodiment, l2 is set to 800, then l1 = -5 / 2 * l2 = -2000, and finally these two numbers are obtained. In addition, the purpose of equation (18) is to obtain Then substitute it into equation (11).

[0138] In this embodiment, the preset motor speed is 1000 r / min, and a load torque T of 50 N·m is applied to the motor at the 3rd second after the start of operation. L The load torque T is observed using the above observer. LThe performance of this observer was simulated and analyzed in the MATLAB / Simulink environment. See details. Figure 3 .

[0139] Depend on Figure 3 The performance of this observer can be analyzed, and the applied load torque can be tracked in about 0.01s.

[0140] 4. Simulation and Result Analysis

[0141] To verify the performance of the novel sliding mode control method designed in this embodiment on the PMSM speed regulation system, simulation studies were conducted in the MATLAB / Simulink environment. This section also constructs a method using the traditional exponential reaching law. A sliding mode speed controller simulation was used for comparison, where n1, n2 > 0. The comparative experiment used the same motor parameters and the same disturbance observer, with a desired speed w* of 1000 r / min. A load torque of 50 N·m was applied simultaneously at the 3rd second and removed at the 4th second. Finally, the effects were compared based on the speed fluctuation graph. The original operating parameters of the PMSM are shown in Table 1.

[0142] Table 1 Operating Parameters of Permanent Magnet Synchronous Motor

[0143] d,q axis inductance L / H 0.00085 <![CDATA[Stator resistance R s / Ω]]> 2.875 <![CDATA[Permanent magnet flux linkage ψ f / (Wb)]]> 0.7 <![CDATA[Moment of inertia J / (kg·m 2 )]]> 0.0008 pole number p 4

[0144] The overall structural block diagram of the PMSM speed control system is as follows: Figure 4 As shown.

[0145] A comparison of simulation curves of the motor during no-load start-up, such as... Figure 5 As shown, the solid line represents the control system of this embodiment, and the dashed line represents the traditional control system using the exponential approach law.

[0146] like Figure 5 As shown, the system expects a speed of 1000 r / min. The motor starts from the zeroth second. It can be seen from the start-up process that when the motor adopts the new approaching law control method of this embodiment, it reaches a stable state of 1000 r / min in about 2 ms. Compared with the traditional approaching law sliding mode control, this method has a faster rise speed, less overshoot and chattering, and the stable state comes much earlier.

[0147] Figure 6 The comparison shows the speed fluctuations of the two systems after the load torque is applied to the motor at 3 seconds. The solid line represents the control system of this embodiment, and the dashed line represents the traditional sliding mode control system using the exponential reaching law.

[0148] Depend on Figure 6It can be seen that when a load torque of 50 N·m is applied to the motor in the 3rd second, the motor speed using the control strategy of this embodiment drops to approximately 916.7 r / min, while the speed of the sliding mode speed controller using the traditional approach law drops to 908.9 r / min. This shows that the speed of the control strategy of this embodiment is less affected by disturbances. In addition, the sliding mode speed controller using the novel approach law of this embodiment only needs about 0.023 seconds to recover the desired speed of 1000 r / min after being disturbed, while the traditional sliding mode requires about 0.047 seconds. This demonstrates that the control strategy of this embodiment recovers faster after being disturbed, has a more linear recovery speed, and higher steady-state accuracy.

[0149] Figure 7 This simulation compares the two control methods after the load is removed in the 4th second. Under traditional sliding mode control, the motor speed rises by approximately 91 r / min after load removal and stabilizes after 0.045 seconds. In contrast, the control strategy in this embodiment only experiences a speed rise of 83 r / min and stabilizes in just 0.023 seconds, while also exhibiting higher steady-state accuracy. Therefore, it can be concluded that the motor speed fluctuation using the control strategy in this embodiment is smaller after load removal, with faster recovery speed, shorter adjustment time, and stronger robustness.

[0150] In summary, the sliding mode speed control system using the control strategy of this embodiment has better overall performance.

[0151] 5. Conclusion

[0152] This embodiment uses a permanent magnet synchronous motor as the object and designs a novel speed controller based on sliding mode algorithm and disturbance observer. Regarding the selection of the reaching law, the advantages and disadvantages of several common reaching laws are comprehensively compared, and a novel reaching law is designed. Utilizing the characteristics of the power-law function, the system's ability to adjust the reaching speed is significantly increased. This allows the system to focus on increasing speed in the reaching phase far from the sliding surface and on reducing chattering in the approach phase, thereby improving the performance of the control system. Simultaneously, to accurately observe load disturbances, this embodiment adds a Luenberger observer to track and calculate the load disturbance value and feed it back to the control law, jointly improving the performance of the control system. The final simulation results show that compared to the traditional exponential reaching law speed regulation method, the control strategy of this embodiment has a faster response speed, less overshoot and chattering, and better system disturbance rejection performance.

[0153] Example 2

[0154] This embodiment provides a speed control design system for a permanent magnet synchronous motor, including:

[0155] First building block: Used to build the mathematical model of the permanent magnet synchronous motor;

[0156] The second construction module is used to construct the sliding surface and the new approach law, and to design the sliding controller based on the sliding surface, the new approach law and the mathematical model of the permanent magnet synchronous motor.

[0157] Design module: Used for designing disturbance observers;

[0158] Speed ​​control module: used to observe the load disturbance of the permanent magnet synchronous motor through the disturbance observer, and compensate the observed value to the sliding mode controller to complete the speed control of the permanent magnet synchronous motor.

[0159] Example 3

[0160] This embodiment provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the steps of the permanent magnet synchronous motor speed control design method described in Embodiment 1.

[0161] Example 4

[0162] This embodiment provides a computer-readable storage medium storing a computer program thereon. When the computer program is executed by a processor, it implements the steps of the permanent magnet synchronous motor speed control design method described in Embodiment 1.

[0163] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code. The solutions in the embodiments of this application can be implemented in various computer languages, such as the object-oriented programming language Java and the interpreted scripting language JavaScript.

[0164] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0165] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0166] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0167] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0168] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A speed control design method for a permanent magnet synchronous motor, characterized in that: include: Step S1: Construct a mathematical model of the permanent magnet synchronous motor, including the following methods: The torque equation for the permanent magnet synchronous motor is constructed as follows: (2)； The equations of motion for the permanent magnet synchronous motor are as follows: (3)； In the formula, Stator current Axial components; This refers to the actual speed of the motor. This represents the number of pole pairs of the motor. For permanent magnet flux linkage; Electromagnetic torque; This is the load torque; It is the moment of inertia; Combining equations (2) and (3), we obtain the mathematical model of the permanent magnet synchronous motor: (4)； Step S2: Construct the sliding surface and the new reaching law, and design a sliding mode controller based on the sliding surface, the new reaching law, and the mathematical model of the permanent magnet synchronous motor. The method includes: The formula for constructing the sliding surface of the sliding mode controller is as follows: (5)； In the formula, , and , It is a positive odd number. Indicates rotational speed error; A new reaching law for the sliding mode controller is constructed, with the following formula: (6)； In the formula, , It is an adjustable parameter. It is a sliding surface; Let the error Let the difference between the desired motor speed and the actual motor speed be denoted by the derivative. (7)； In the formula, Given the motor speed, This refers to the actual speed of the motor; Error Substitute into the sliding surface of formula (5) Equation (8) is obtained and its derivative is taken: (8)； Substituting equation (7) into equation (8), we get: (9)； Substituting equations (4) and (6) into equation (9), we obtain the sliding mode controller for the permanent magnet synchronous motor: (10)； In the formula, This is the observed value of the load torque; Step S3: Design a disturbance observer; Step S4: The load disturbance of the permanent magnet synchronous motor is observed by the disturbance observer, and the observed value is compensated to the sliding mode controller to complete the speed regulation of the permanent magnet synchronous motor.

2. The speed regulation design method for a permanent magnet synchronous motor according to claim 1, characterized in that: The stability of the sliding mode controller is analyzed by means of: Selecting Lyapunov functions: (12); Differentiating equation (12) and combining it with equation (6), we get: (13)； In the formula, ,and , , Therefore, we can obtain According to the Lyapunov stability criterion, the sliding mode controller tends to stabilize.

3. The speed regulation design method for a permanent magnet synchronous motor according to claim 1, characterized in that: The method for designing the disturbance observer in step S3 includes: Using motor speed and load torque as state variables, the state equation of equation (14) is constructed as follows: (14)； In the formula, They refer to each other and ; Let the coefficient matrix of equation (14) be: (15)； Let the disturbance observer output error feedback matrix be... : (16)； In the formula, The error feedback parameter is a constant value; The coefficient matrix of the perturbation observer is then: (17)； The feedback matrix in the disturbance observer needs to be determined. Preset The eigenvalues ​​have negative real parts, and Equation (18) is constructed according to Equations (14)-(17). Then Equation (18) is the final perturbation observer equation. (18)； In the formula, This is the observed value of the motor speed.

4. The speed regulation design method for a permanent magnet synchronous motor according to claim 1, characterized in that: The control law of the permanent magnet synchronous motor is obtained by rearranging formula (10): (11)。 5. A speed control design system for a permanent magnet synchronous motor, used to implement the speed control design method for a permanent magnet synchronous motor as described in claim 1, characterized in that: include: First building block: Used to build the mathematical model of the permanent magnet synchronous motor; The second construction module is used to construct the sliding surface and the new approach law, and to design the sliding controller based on the sliding surface, the new approach law and the mathematical model of the permanent magnet synchronous motor. Design module: Used for designing disturbance observers; Speed ​​control module: used to observe the load disturbance of the permanent magnet synchronous motor through the disturbance observer, and compensate the observed value to the sliding mode controller to complete the speed control of the permanent magnet synchronous motor.

6. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, it implements the steps of the permanent magnet synchronous motor speed control design method as described in any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the permanent magnet synchronous motor speed control design method as described in any one of claims 1 to 4.

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