Control method and device for increasing thrust of permanent magnet synchronous motor during high-speed operation
By building a dual-ring control system with alternating control of speed ring and current ring in a permanent magnet synchronous motor, the problems of reduced power angle, reduced thrust and increased fluctuation during high-speed operation are solved, and the smooth operation of the motor and stable increase in thrust are achieved.
Patent Information
- Application Number
- CN202410035357.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-09
- Publication Date
- 2025-03-14
AI Technical Summary
When the permanent magnet synchronous motor is running at high speed, due to the long speed ring control period, the work angle is greatly reduced, the thrust is reduced and the thrust fluctuation increases, which affects the stable operation of the motor.
A double-ring control system with alternating control of speed ring and current ring is constructed. The power angle of the motor is periodically updated according to the first control cycle through the speed ring, and the running speed of the mover is periodically collected according to the second control cycle through the current ring, the running distance is calculated and the power angle is compensated to control the motor to operate according to the compensating thrust during the first control cycle.
Through the alternating control of the dual-ring control system, the average thrust of the motor in one cycle is increased, the smooth operation of the motor is ensured, and the thrust fluctuation is reduced.
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Figure CN119628490A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of motor control technology, and in particular to a control method and device for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed. Background Art
[0002] Permanent magnet synchronous motors are increasingly being used due to their fast response speed, fast acceleration, high precision, stable operation, etc. Taking the moving magnet permanent magnet synchronous motor as an example, the basic principle of the permanent magnet synchronous motor is to pass current through the primary coil to generate a magnetic field, which reacts with the fixed permanent magnet magnetic field in the secondary to generate thrust, thereby driving the mover to move.
[0003] In the control algorithm of permanent magnet synchronous motor, in order to achieve the goal of maximum thrust, the control power angle of the motor is often set to 90°, and the speed loop control is used to periodically update the power angle. However, this method can actually only guarantee the maximum thrust of the motor when the 90° power angle condition is met. In the time between two power angle updates, that is, in the control cycle of the speed loop, since the speed loop control does not update the power angle, and since the control cycle of the speed loop is long, the high-speed moving rotor will run a long distance in the control cycle, resulting in a significant reduction in the power angle, a reduction in the motor thrust and an increase in thrust fluctuations, affecting the stable operation of the motor. Summary of the invention
[0004] Based on this, it is necessary to provide a control method and device for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed, thereby increasing the average thrust of the motor within a cycle and ensuring the smooth operation of the motor, in order to solve the above technical problems.
[0005] A control method for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed, the method comprising:
[0006] Construct a dual-loop control system of alternating control of a speed loop and a current loop, and set a first control cycle and a second control cycle of the dual-loop control system;
[0007] After the permanent magnet synchronous motor starts running, the timing starts, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at the maximum thrust according to the target power angle obtained after the update;
[0008] In the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0009] In one embodiment, the first control period is determined by the control frequency of the speed loop, and the second control period is determined by the control frequency of the current loop.
[0010] In one embodiment, the first control period is greater than the second control period.
[0011] In one embodiment, the thrust of the motor is a sinusoidal function value of the power angle multiplied by a set proportional number k, and k is greater than zero.
[0012] In one embodiment, the target power angle is 90°.
[0013] In one of the embodiments, in a first control cycle, the running speed of the mover is periodically collected according to a second control cycle through a current loop in a dual-loop control system, and the running distance of the mover in the second control cycle is calculated, and the power angle of the motor is compensated according to the running distance, including:
[0014] In the first control cycle T1, the running speed v of the mover is periodically collected according to the second control cycle T2 through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle T2 is calculated and expressed as s=v×T, where T represents the timing duration of the timer in the second control cycle T2. After each T2 is completed, the timer is reset;
[0015] The power angle of the motor is compensated according to the running distance s, and the compensated power angle is obtained, which is expressed as Among them, θ0 is the target power angle, S is the magnetic field period of the motor, and one magnetic field period corresponds to 360°. is the magnetic field angle of the mover.
[0016] In one embodiment, the control function of the current loop is implemented using FPGA.
[0017] A control device for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed, the device comprising:
[0018] A control system building module, used to build a dual-loop control system of alternating control of a speed loop and a current loop, and to set a first control cycle and a second control cycle of the dual-loop control system;
[0019] A power angle update module is used to start timing after the permanent magnet synchronous motor starts running, periodically update the power angle of the motor according to the first control period through the speed loop in the dual-loop control system, and control the motor to run at maximum thrust according to the target power angle obtained after the update;
[0020] The power angle compensation module is used to periodically collect the running speed of the mover in the first control cycle through the current loop in the dual-loop control system according to the second control cycle, calculate the running distance of the mover in the second control cycle, compensate the power angle of the motor according to the running distance, and control the motor to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0021] A computer device comprises a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:
[0022] Construct a dual-loop control system of alternating control of a speed loop and a current loop, and set a first control cycle and a second control cycle of the dual-loop control system;
[0023] After the permanent magnet synchronous motor starts running, the timing starts, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at the maximum thrust according to the target power angle obtained after the update;
[0024] In the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0025] A computer-readable storage medium stores a computer program, which, when executed by a processor, implements the following steps:
[0026] Construct a dual-loop control system of alternating control of a speed loop and a current loop, and set a first control cycle and a second control cycle of the dual-loop control system;
[0027] After the permanent magnet synchronous motor starts running, the timing starts, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at the maximum thrust according to the target power angle obtained after the update;
[0028] In the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0029] The above-mentioned control method for increasing the thrust of a permanent magnet synchronous motor when it is running at high speed constructs a dual-loop control system of alternating control of a speed loop and a current loop. During the high-speed operation of the motor, the power angle of the motor is periodically updated by the speed loop according to the first control cycle, thereby controlling the motor to operate at the maximum thrust, and in the first control cycle, the power angle of the motor is compensated by the current loop according to the second control cycle, thereby controlling the motor to operate at the compensated thrust in the first control cycle. Compared with the existing motor control algorithm that only uses the speed loop to periodically update the power angle, the present application adopts a strategy of alternating control of the speed loop and the current loop, which compensates the motor thrust while ensuring that the motor reaches the maximum thrust, increases the average thrust of the motor and reduces the thrust fluctuation, and realizes the smooth operation of the motor when it moves at high speed. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Figure 1 It is a flow chart of a control method for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed in one embodiment;
[0031] Figure 2 It is a structural block diagram of a control device for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed in one embodiment;
[0032] Figure 3 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION
[0033] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application 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 application and are not used to limit the present application.
[0034] In one embodiment, Figure 1 As shown, a control method for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed is provided, comprising the following steps:
[0035] Step S1, constructing a dual-loop control system with alternating control of a speed loop and a current loop, and setting a first control period and a second control period of the dual-loop control system. The first control period is determined by the control frequency of the speed loop, the second control period is determined by the control frequency of the current loop, and the first control period is greater than the second control period.
[0036] It is understandable that, because the speed loop uses a relatively complex control algorithm and has to exchange more data with the outside world, and is also limited by the response time of the position sensor, the control frequency of the speed loop is usually around 2k-4k; while the control function of the current loop is relatively simple, with a single calculation, and can be implemented using FPGA (field programmable gate array), so its control frequency can be 20k or even higher. Therefore, the control period of the speed loop is much larger than that of the current loop.
[0037] Step S2, after the permanent magnet synchronous motor starts running, the timing starts, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at the maximum thrust according to the target power angle obtained after the update. The thrust of the motor operation is the sine function value of the power angle multiplied by a set ratio k, and k is greater than zero. When the target power angle is 90°, the motor reaches the target of maximum thrust.
[0038] Step S3, within the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover within the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust within the first control cycle according to the obtained compensated power angle.
[0039] Specifically, in the first control cycle T1, that is, after obtaining the currently updated target power angle and before the next update of the motor power angle, the current loop in the dual-loop control system periodically collects the running speed v of the mover according to the second control cycle T2, and calculates the running distance of the mover in the second control cycle T2, which is expressed as s=v×T, where T represents the timing duration of the timer in the second control cycle T2, and the timer restarts after each T2 is completed;
[0040] The power angle of the motor is compensated according to the running distance s, and the compensated power angle is obtained, which is expressed as Among them, θ0 is the target power angle, S is the magnetic field period of the motor, and one magnetic field period corresponds to 360°. is the magnetic field angle of the mover.
[0041] It can be understood that since the control cycle of the speed loop is much larger than the control cycle of the current loop, when the power angle compensation is performed through the current loop in the first control cycle, the running distance of the high-speed moving element in the second control cycle is very short, and the magnetic field angle of the moving element in the second control cycle is very small. In this case, according to the calculation formula of the above-mentioned compensation power angle, it can be seen that the angle difference between the compensation power angle and the target power angle is very small. Therefore, when the motor is controlled to operate according to the compensation thrust through the compensation power angle, the thrust fluctuation is significantly reduced compared to the motor running according to the maximum thrust, and the average thrust of the motor is increased, and the motor runs more smoothly.
[0042] In a specific embodiment, the beneficial effect of a control method for increasing the thrust of a permanent magnet synchronous motor during high-speed operation provided by the present application is further demonstrated, and is explained in conjunction with the specific parameters of the permanent magnet synchronous motor: the mover movement speed is 8 m / s, the control period of the speed loop is 0.5 msec (the control frequency is 2K), and the pole pitch of the motor is 10 mm (the magnetic field period of the motor is 20 mm, and one magnetic field period corresponds to 360°).
[0043] When only the speed loop control algorithm is used to control the motor operation, the speed loop is used to periodically update the power angle of the motor to 90°. However, after 0.5 milliseconds (before the next power angle update is completed), the mover runs 4 mm, and the corresponding running magnetic field angle is (4 / 20)*360=72°. At this time, the power angle changes to 90°-72°=18°. Assuming that the maximum thrust of the motor is 1 when the power angle is 90°, when the power angle is 18°, the thrust of the motor is sin(18°)=0.3, which is only 30% of the maximum thrust. It can be seen that during high-speed movement, this control algorithm not only has a large thrust fluctuation, but also significantly reduces the thrust of the motor.
[0044] And sampling the method proposed in this application, since the control frequency of the current loop is 20k, its control period is 0.05 milliseconds, so that when the moving speed of the mover is 8 meters per second, between each control cycle of the current loop, the moving distance of the mover is 0.4 mm, and the corresponding running magnetic field angle is (0.4 / 20)*360=7.2°, at this time the compensation power angle is 90°-7.2°=81.8°, and it is also assumed that the maximum thrust of the motor is 1 when the power angle is 90°, and the compensation thrust of the motor is sin(81.8°)=0.99 when the power angle is 81.8°, which is equivalent to 99% of the maximum thrust. It can be seen that at any time, the value of the motor thrust using this method is above 99% of the maximum value. It can be seen that when moving at high speed, the control method provided by this application can reduce the thrust fluctuation of the motor, make the motor run more smoothly, and significantly increase the average thrust of the motor.
[0045] It should be understood that although Figure 1The steps in the flowchart are shown in sequence as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified in this document, there is no strict order restriction for the execution of these steps, and these steps can be executed in other orders. Moreover, Figure 1 At least part of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least part of the sub-steps or stages of other steps.
[0046] In one embodiment, Figure 2 As shown, a control device for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed is provided, comprising:
[0047] A control system construction module 201 is used to construct a dual-loop control system of alternating control of a speed loop and a current loop, and to set a first control period and a second control period of the dual-loop control system;
[0048] The power angle update module 202 is used to start timing after the permanent magnet synchronous motor starts running, periodically update the power angle of the motor according to the first control period through the speed loop in the dual-loop control system, and control the motor to run at the maximum thrust according to the target power angle obtained after the update;
[0049] The power angle compensation module 203 is used to periodically collect the running speed of the mover in the first control cycle through the current loop in the dual-loop control system according to the second control cycle, calculate the running distance of the mover in the second control cycle, compensate the power angle of the motor according to the running distance, and control the motor to operate according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0050] For the specific definition of a control device for increasing the thrust of a permanent magnet synchronous motor when it is running at high speed, please refer to the definition of a control method for increasing the thrust of a permanent magnet synchronous motor when it is running at high speed in the above text, which will not be repeated here. Each module in the above-mentioned control device for increasing the thrust of a permanent magnet synchronous motor when it is running at high speed can be implemented in whole or in part by software, hardware and a combination thereof. The above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory in the computer device in the form of software, so that the processor can call and execute the operations corresponding to the above modules.
[0051] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 3As shown. The computer device includes a processor, a memory, a network interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The network interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a control method for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a button, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.
[0052] Those skilled in the art will understand that Figure 3 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.
[0053] In one embodiment, a computer device is provided, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the following steps are implemented:
[0054] Construct a dual-loop control system of alternating control of a speed loop and a current loop, and set a first control cycle and a second control cycle of the dual-loop control system;
[0055] After the permanent magnet synchronous motor starts running, the timing starts, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at the maximum thrust according to the target power angle obtained after the update;
[0056] In the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0057] In one embodiment, a computer readable storage medium is provided, on which a computer program is stored, and when the computer program is executed by a processor, the following steps are implemented:
[0058] Construct a dual-loop control system of alternating control of a speed loop and a current loop, and set a first control cycle and a second control cycle of the dual-loop control system;
[0059] After the permanent magnet synchronous motor starts running, the timing starts, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at the maximum thrust according to the target power angle obtained after the update;
[0060] In the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
[0061] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).
[0062] The technical features of the above embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0063] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.
Claims
1. A control method for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed, characterized in that: The method comprises: Constructing a dual-loop control system in which a speed loop and a current loop are alternately controlled, and setting a first control cycle and a second control cycle of the dual-loop control system; After the permanent magnet synchronous motor starts running, timing is started, the power angle of the motor is periodically updated according to the first control period through the speed loop in the dual-loop control system, and the motor is controlled to run at maximum thrust according to the target power angle obtained after the update; During the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover during the second control cycle is calculated, the power angle of the motor is compensated according to the running distance, and the motor is controlled to run according to the compensated thrust during the first control cycle according to the obtained compensated power angle.
2. The method according to claim 1, characterized in that The first control period is determined by the control frequency of the speed loop, and the second control period is determined by the control frequency of the current loop.
3. The method according to claim 2, characterized in that The first control period is greater than the second control period.
4. The method according to claim 1, characterized in that: The thrust of the motor operation is the sinusoidal function value of the power angle multiplied by a set proportional number k, and k is greater than zero.
5. The method according to claim 1, characterized in that The target power angle is 90°.
6. The method according to claim 1, characterized in that In the first control cycle, the running speed of the mover is periodically collected according to the second control cycle through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle is calculated, and the power angle of the motor is compensated according to the running distance, including: In the first control cycle T1, the running speed v of the mover is periodically collected according to the second control cycle T2 through the current loop in the dual-loop control system, and the running distance of the mover in the second control cycle T2 is calculated and expressed as s=v×T, where T represents the timing duration of the timer in the second control cycle T2, and the timer is reset after each T2 is completed; The power angle of the motor is compensated according to the running distance s, and the compensated power angle is obtained, which is expressed as Among them, θ0 is the target power angle, S is the magnetic field period of the motor, and one magnetic field period corresponds to 360°. is the magnetic field angle of the mover.
7. The method according to claim 1, 2 or 6, characterized in that: The control function of the current loop is implemented using FPGA.
8. A control device for increasing the thrust of a permanent magnet synchronous motor when it runs at high speed, characterized in that: The device comprises: A control system construction module, used to construct a dual-loop control system of alternating control of a speed loop and a current loop, and to set a first control period and a second control period of the dual-loop control system; A power angle update module, configured to start timing after the permanent magnet synchronous motor starts running, periodically update the power angle of the motor according to the first control period through the speed loop in the dual-loop control system, and control the motor to run at maximum thrust according to the target power angle obtained after the update; A power angle compensation module is used to periodically collect the running speed of the mover in the first control cycle through the current loop in the dual-loop control system according to the second control cycle, calculate the running distance of the mover in the second control cycle, compensate the power angle of the motor according to the running distance, and control the motor to run according to the compensated thrust in the first control cycle according to the obtained compensated power angle.
9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 7 are implemented.
10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are implemented.