Method for controlling direct drive system, computer device, and computer-readable storage medium

Abstract

The present invention provides a method for controlling a direct drive system. The method includes the steps of: (S1) a driver outputs a current to a corresponding winding of a stator, so that the winding drives the corresponding mover to move in a single direction along a guide rail; (S2) a first position feedback device senses the position of the mover relative to the stator with a second position feedback device; and (S3) a driver adjusts the magnitude of the current output to the corresponding winding of the stator based on the driving mode by changing the driving mode of the driver based on the position information. Compared with the prior art, the present invention can control a direct drive system with multiple coils as one stator, and can reduce the number of power modules used in the direct drive system, thereby reducing the production and usage costs of the entire direct drive system.

Description

[Technical field]

[0001] The present invention relates to the technical field of direct drive transport, and in particular to a control method and related device for a direct drive system. [Background technology]

[0002] With the development of motor technology, various types of motors are now being used on production lines in various manufacturing industries, and among these, direct drive transport systems using direct drive motors are widely used in production line scenes such as for transporting parts, and at the same time, methods of precisely controlling the position of each transport unit using the transport system are gradually being adopted.

[0003] The driving method employed in conventional direct drive conveying systems in the related art involves independently controlling each coil in the winding, and when the mover moves to a specific position, current is applied to the corresponding coil, thereby driving the magnetic steel in the mover to move. Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the direct drive conveying system of the prior art, each coil needs to be driven independently, and in order to achieve this, a higher-level system needs to perform overall cooperative control, and when there are multiple windings and coils, the driving and control methods used in the direct drive conveying system of the prior art are more complicated. Secondly, from the viewpoint of manufacturing, a direct drive conveying system in which each coil is driven independently requires a large number of power modules, which leads to increased manufacturing and usage costs.

[0005] Therefore, there is a need to provide a new direct drive system control method to solve the above problems. [Means for solving the problem]

[0006] The technical problem to be solved by the present invention is to provide a method for controlling multiple coils as one stator and reducing the number of power modules in a direct drive system.

[0007] In order to solve the above technical problems, as a first aspect, the present invention provides a control method for a direct drive system, the direct drive system including a guide rail, a plurality of stators affixed to the guide rail, a plurality of movers slidably provided on the guide rail, actuators corresponding to the respective stators, and a controller for controlling all of the actuators, each of the stators including a stator body, a plurality of windings fixed to the stator body, and a first position feedback device, each of the movers including a mover body, a magnetic steel fixed to the mover body, and a second position feedback device, the windings being provided directly opposite the magnetic steel, and the control method includes: S1, the driver outputs a current to the corresponding winding of the stator, so that the winding drives the corresponding mover to move in a single direction along the guide rail; S2, the first position feedback device senses the position of the second position feedback device to obtain position information of the mover relative to the stator, and transmits the position information to the controller; S3, changing a drive mode of the driver based on the position information, whereby the driver adjusts the magnitude of the current output to the corresponding winding of the stator based on the drive mode.

[0008] Preferably, the driving modes include a master axis mode and a slave axis mode, and when the driver is in the master axis mode, the driver adjusts the magnitude of the output current of the corresponding winding of the stator in real time based on the position information; When the driver is in the slave axis mode, the magnitude of the current that the driver outputs to the corresponding winding of the stator is constant.

[0009] Preferably, when the magnetic steel of the mover is completely within a driving range of the winding of the stator, the controller controls the driver corresponding to the stator to be in the master axis mode; When the magnetic steel in the mover is completely outside the driving range of the windings of the stator, the controller controls the driver corresponding to the stator to enter the slave axis mode.

[0010] Preferably, the plurality of stators include at least a first stator and a second stator provided adjacent to each other, the actuators corresponding to the first stator and the second stator are a first actuator and a second actuator, respectively, the first stator has a first winding, the second stator has a second winding, the first winding and the second winding are provided facing the magnetic steel, respectively, the mover moves in a single direction along the guide rail, and when the mover approaches positions facing the first stator and the second stator in sequence, the driving modes of the first actuator and the second actuator change in sequence and continuously as follows: When the mover moves to a position directly opposite the first winding, the first driver is in the master axis mode and the second driver is in the slave axis mode, When the mover moves to a position directly facing a portion adjacent to the first winding and the second winding, the first driver is in the master axis mode and the second driver is in the master axis mode, When the mover moves to a position directly facing the second winding, the first driver is in the slave axis mode, and the second driver is in the master axis mode.

[0011] Preferably, the first and second actuators generate driving forces in the magnetic steel of the same mover in the same direction.

[0012] Preferably, the drivers corresponding to the first stator and the second stator are connected to the same controller, and the controller centrally controls switching of the drive modes of the drivers.

[0013] Preferably, the controller calculates absolute position information of the mover moving on the guide rail based on the position information.

[0014] Preferably, the first position feedback device is a read head and the second position feedback device is a grid ruler, the read head being disposed directly opposite the grid ruler.

[0015] As a second aspect, an embodiment of the present invention further provides a computer device, the computer device including a memory, a processor, and a computer program stored in the memory and executable on the processor, and when the processor executes the computer program, steps in the control method for the direct drive system in the above embodiment are realized.

[0016] As a third aspect, an embodiment of the present invention further provides a computer-readable storage medium having a computer program stored therein, the computer program causing a processor to execute the steps of the method for controlling a direct drive system according to the embodiment. Effect of the Invention

[0017] Compared with the prior art, the control method of the direct drive system provided by the present invention is used in a direct drive system with multiple coils as one stator, each stator is driven by one independent driver, and one independent controller controls all the drivers, so that the driving modes of different stators can be easily switched and the complicated control operation problem of multiple control units can be avoided. At the same time, the method of integrating multiple coils into one stator and driving one stator with one driver can effectively reduce the number of power modules used in the direct drive system, and reduce the production and use costs of the entire direct drive system. [Brief description of the drawings]

[0018] In order to more clearly describe the technical solutions in the embodiments of the present invention, the following will briefly describe the drawings that need to be used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can further obtain other drawings based on these drawings without creative work, among which: [Figure 1] FIG. 1 is a schematic diagram showing the configuration of a direct drive system used in an embodiment of the present invention. [Diagram 2] 4 is a flowchart of steps of a control method for a direct drive system provided by an embodiment of the present invention. [Diagram 3] FIG. 2 is a schematic diagram showing the change of the driving mode of the actuator when the mover moves across the stator in the direct drive system provided by the embodiment of the present invention; [Figure 4] FIG. 2 is a schematic diagram of the configuration of a computer device provided by an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, the technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative labor are all within the scope of protection of the present invention.

[0020] As shown in Fig. 1, Fig. 1 is a schematic diagram of a direct drive system 100 used in an embodiment of the present invention. Taking the configuration of one set of a stator and a mover in the direct drive system 100 as an example, the direct drive system 100 includes a guide rail 1, a stator 2 attached to the guide rail 1 and having a first position feedback device 21, a mover 3 slidably provided on the guide rail 1 and having a second position feedback device 31, a driver 4 corresponding to the stator 2, and a controller 5 for controlling the driver 4, the mover 3 includes a mover body 32 and a magnetic steel 33 fixed to the mover body 32, and the stator 2 includes a stator body 22 and a plurality of windings 23 fixed to the stator body, the windings 23 being provided facing the magnetic steel 33. The first position feedback device 21 and the second position feedback device 31 are both photoelectric sensing devices, and the first position feedback device 21 and the second position feedback device 31 are provided facing each other. Specifically, when the first position feedback device 21 and the second position feedback device 31 are in a facing state, the first position feedback device 21 can obtain the relative position of the second position feedback device 31.

[0021] The stator 2 includes a plurality of windings 23, and when configured as a stator, the plurality of windings 23 constitute the first stage of one stator, and the direct drive system 100 includes the same plurality of sets of stators and mover configurations as described above, and each of the stators is correspondingly controlled by one of the drivers, but the system can include at least one controller.

[0022] Referring to FIG. 2, FIG. 2 is a step flowchart of a control method for a direct drive system provided in an embodiment of the present invention, and the method includes the following steps S1 to S3.

[0023] S1, the driver outputs a current to the corresponding winding of the stator, so that the winding drives the corresponding mover to move in a single direction along the guide rail.

[0024] Specifically, taking the above-mentioned direct drive system 100 as an example, when the direct drive system 100 is on standby, an air gap magnetic field is generated between the magnetic steel 33 of the mover 3 and the winding 23 of the stator 2 in the vicinity thereof, and the driver 4 outputs current to the first stage constituted by the winding 23, causing the winding 23 to generate a traveling wave magnetic field, and further generating a thrust force between the magnetic steel 33 of the mover 3 and the energized winding 23, causing the mover body 32 to move in the direction of the thrust force along the guide rail 1.

[0025] In S2, the first position feedback device performs position sensing on the second position feedback device to obtain position information of the mover relative to the stator.

[0026] When the first position feedback device 21 and the second position feedback device 31 are in an opposing state, i.e., when the first position feedback device 21 and the second position feedback device 31 are in a position similar to that in Figure 2, a part of the position of the second position feedback device 31 is directly opposite the first position feedback device 21, and at this time, the first position feedback device 21 can obtain the relative position of the second position feedback device 31, and then the first position feedback device 21 transmits the obtained position information to the controller 5.

[0027] S3: changing a driving mode of the driver based on the position information, and the driver adjusting a magnitude of a current output to the corresponding winding of the stator based on the driving mode.

[0028] Preferably, the driving modes include a master axis mode and a slave axis mode, and when the driver 4 is in the master axis mode, the driver 4 adjusts in real time the magnitude of the current output to the corresponding winding 23 of the stator 2 based on the position information; When the driver 4 is in the slave axis mode, the magnitude of the current that the driver 4 outputs to the corresponding winding 23 of the stator 2 is constant.

[0029] In general, the thrust force generated between the winding 23 and the magnetic steel 33 varies depending on the magnitude of the current output by the driver 4 to the winding 23. In the embodiment of the present invention, when the driver 4 is in the master axis mode, the driver 4 adjusts the output current more finely based on the position information. For example, when the position of the entire mover 3 moves along its moving direction and gradually approaches the position of the stator 2, the output current should be as large as possible to ensure the acceleration performance of the mover 3. When the mover 3 gradually moves away from the stator 2 in its moving direction, the output current should be gradually decreased to avoid the speed fluctuation of the mover 3. Such dynamic current adjustment allows a power module such as the driver 4 to control multiple sets of windings while saving as much power as possible.

[0030] Preferably, when the magnetic steel of the mover is completely within a driving range of the winding of the stator, the controller controls the driver corresponding to the stator to be in the master axis mode; When the magnetic steel in the mover is completely outside the driving range of the windings of the stator, the controller controls the driver corresponding to the stator to enter the slave axis mode.

[0031] Preferably, the present invention provides a specific embodiment to further illustrate the effect of the change of the driving mode of the driver on the movement of the stator.

[0032] Referring to FIG. 3, FIG. 3 is a schematic diagram of the change in the driving mode of the actuator when the movable member moves across the stator in the direct drive system provided by the embodiment of the present invention, the plurality of stators include at least a first stator and a second stator arranged adjacent to each other, the actuators corresponding to the first stator and the second stator are a first actuator 4 and a second actuator 6, the first stator has a first winding, the second stator has a second winding, the first winding and the second winding are respectively arranged directly opposite the magnetic steel, the movable member 3 moves in a single direction along the guide rail 1, and when it sequentially approaches the positions corresponding to the first stator and the second stator, the driving modes of the first actuator 4 and the second actuator 6 change continuously in sequence as follows: When the mover moves to a position directly facing the first winding, the first driver 4 is in the master axis mode and the second driver 6 is in the slave axis mode. When the mover moves to a position directly facing a portion adjacent to the first winding and the second winding, the first driver 4 is in the master axis mode, and the second driver 6 is in the master axis mode, When the mover moves to a position directly facing the second winding, the first driver 4 is in the slave axis mode, and the second driver 6 is in the master axis mode.

[0033] In the embodiment of the present invention, if the driving mode of the driver corresponding to the stator is the master axis mode, it indicates that the current stator generates the main acting force on the mover, and when the first driver 4 is in the master axis mode and the second driver 6 is in the master axis mode, the position of the magnetic steel 33 of the mover 3 is exactly at the position where the first winding and the second winding are adjacent to each other at the same time, in this case, it is necessary to ensure that at least one driver of the stator is in the master axis mode, so that the mover 3 can receive a sufficient acting force and keep its moving state. That is, in one possible embodiment, when the position of the magnetic steel 32 of the mover 3 is exactly at the position where the first winding and the second winding are adjacent to each other at the same time, the driving modes corresponding to the first driver 4 and the second driver 6 may be as follows: the driver 4 is in the master axis mode and the second driver 6 is in the slave axis mode; Or, The driver 4 is in the slave axis mode and the second driver 6 is in the master axis mode.

[0034] Here, how to determine the relationship between the position of the magnetic steel 33 of the mover 3 and the positions of the windings of the first stator 2 and the second stator 6 is specifically obtained by the first position feedback device 21 of each of the stators sensing the second position feedback device 31 of the mover.

[0035] Preferably, the first and second actuators generate driving forces in the magnetic steel of the same mover in the same direction.

[0036] Such an installation is for the purpose of preventing an unstable phenomenon from occurring when the mover 3 moves on the guide rail 1 .

[0037] Preferably, the drivers corresponding to the first stator and the second stator are connected to the same controller, and the controller centrally switches the drive modes of the drivers.

[0038] Preferably, the controller calculates absolute position information of the mover moving on the guide rail based on the position information.

[0039] In the direct drive system 100, in order to avoid a large difference in the currents output by the different actuators or the generation of a current that acts to direct the mover in different directions, it is necessary to prevent the speed of the same mover from fluctuating due to differences in the control commands received by the actuators while it is moving, by controlling them in an integrated manner by the controller. In addition, when the controller acquires the position information, it can obtain absolute position information of the mover 3 moving on the guide rail 1 based on the position information. For example, when the stator whose position information is acquired is fixed in position in the direct drive system 100, the relative position of the mover 3 can be obtained by the first position feedback device 21 and the second position feedback device 31, which are photoelectric sensing devices, and further the absolute position of the mover 3 is calculated and obtained by the controller 5.

[0040] The controller 5 can adjust the drive mode of each of the actuators in real time based on the absolute position, thereby controlling the movement of multiple movers in the direct drive system and reducing the operational complexity of the entire direct drive system from the control level.

[0041] Preferably, the first position feedback device 21 is a read head for acquiring photoelectric signals, and the second position feedback device 31 is a grid ruler with matching spacing distance.

[0042] Compared with the prior art, the control method of the direct drive system provided by the present invention, in a direct drive system with multiple coils as one stator, each stator is driven by one independent driver, and all the drivers are controlled by one independent controller, so that it is easy to switch between different stator driving modes and avoid the complicated problem of control operation by multiple control units. In addition, the method of integrating multiple coils into one stator and driving one stator with one driver can effectively reduce the number of power modules used in the direct drive system, and reduce the production and use costs of the entire direct drive system.

[0043] An embodiment of the present invention further provides a computer device, as shown in Fig. 4, which is a schematic diagram of a computer device provided by an embodiment of the present invention. The computer device 200 includes a processor 201, a memory 202, and a computer program stored in the memory 202 and executable on the processor 201.

[0044] The computer device 200 corresponds to the controller 5 in the direct drive system 100 in the above embodiment of the present invention.

[0045] The processor 201 calls a computer program stored in the memory 202, and when the computer program is executed, steps in the control method for the direct drive system in the above embodiment are realized.

[0046] The computer device 200 provided in the embodiment of the present invention can realize the steps in the control method for a direct drive system in the above embodiment, and can achieve similar technical effects. Therefore, the description in the above embodiment can be referred to and will not be repeated here.

[0047] An embodiment of the present invention further provides a computer-readable storage medium, in which a computer program is stored, which, when executed by a processor, realizes each process and step in the control method for a direct drive system provided by the embodiment of the present invention, and can achieve similar technical effects, which will not be repeated here in order to avoid redundancy.

[0048] Those skilled in the art will understand that the implementation of all or part of the steps in the above-mentioned embodiments of the method can be completed by instructing relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium, and when the program is executed, the steps in the above-mentioned embodiments of the method can be included. Among them, the storage medium can be a magnetic disk, an optical disk, a read-only memory (ROM), a random access memory (RAM), etc.

[0049] It should be noted that, as used herein, the terms "comprise," "comprises," or any other variation thereof, are intended to include a non-exclusive inclusion, whereby a process, method, article, or apparatus of a set of elements not only includes those elements, but also includes other elements not expressly listed or includes elements inherent in such process, method, article, or apparatus. Absent more limitations, an element qualified by the phrase "comprises a..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0050] From the above description of the embodiments, those skilled in the art can understand that the methods of the above embodiments can be realized in the form of software and a necessary general-purpose hardware platform, and of course, hardware may also be used, but in many cases the former is a more preferred embodiment. Based on this understanding, the technical solution of the present invention can be essentially or the part that contributes to the prior art can be expressed in the form of a software product, and the computer software product is stored in a storage medium (e.g., ROM / RAM, magnetic disk, optical disk) and contains multiple commands to make a terminal (which may be a mobile phone, a computer, a server, an air conditioner, or a network device, etc.) execute the methods described in each embodiment of the present invention.

[0051] The above description is merely an embodiment of the present invention and does not limit the scope of the claims of the present invention. Any equivalent structure or equivalent flow conversion made by utilizing the contents of the specification and drawings of the present invention, or any direct or indirect application to other related technical fields, is similarly included in the scope of the claims of the present invention.

Claims

1. 1. A method for controlling a direct drive system, comprising: The direct drive system includes a guide rail, a plurality of stators affixed to the guide rail, a plurality of movers slidably provided on the guide rail, actuators corresponding to the respective stators, and a controller for controlling all of the actuators, each of the stators includes a stator body, a plurality of windings fixed to the stator body, and a first position feedback device, each of the movers includes a mover body, a magnetic steel fixed to the mover body, and a second position feedback device, the windings being provided directly opposite the magnetic steel, and the control method includes: S1, the driver outputs a current to the corresponding winding of the stator, so that the winding drives the corresponding mover to move in a single direction along the guide rail; S2: obtaining position information of the mover relative to the stator by the first position feedback device performing position sensing on the second position feedback device; S3, changing a driving mode of the driver based on the position information, and the driver adjusting a magnitude of a current output to the corresponding winding of the stator based on the driving mode; the driving modes include a master axis mode and a slave axis mode, and when the driver is in the master axis mode, the driver adjusts in real time a magnitude of a current output to the corresponding winding of the stator based on the position information; When the driver is in the master axis mode, as the position of the entire mover moves along its moving direction and gradually approaches the position of the stator, the driver gradually increases the current output to the winding, and as the mover gradually moves away from the stator in its moving direction, the driver gradually decreases the current output to the winding; 2. A method for controlling a direct drive system, comprising the steps of: when the actuator is in the slave axis mode, a magnitude of a current output by the actuator to the corresponding winding of the stator is constant.

2. When the magnetic steel of the mover is completely within the driving range of the winding of the stator, the controller controls the driver corresponding to the stator to be in the master axis mode; 2. The method for controlling a direct drive system according to claim 1, wherein when the magnetic steel in the mover is completely outside the driving range of the winding of the stator, the controller controls the driver corresponding to the stator to be in the slave axis mode.

3. The plurality of stators include at least a first stator and a second stator provided adjacent to each other, the drivers corresponding to the first stator and the second stator are a first driver and a second driver, respectively, the first stator has a first winding, the second stator has a second winding, the first winding and the second winding are provided facing the magnetic steel, and when the mover moves in a single direction along the guide rail and sequentially approaches positions facing the first stator and the second stator, the driving modes of the first driver and the second driver are sequentially and continuously changed as follows: When the mover moves to a position directly facing the first winding, the first driver is in the master axis mode and the second driver is in the slave axis mode, When the mover moves to a position directly facing a portion adjacent to the first winding and the second winding, the first driver is in the master axis mode and the second driver is in the master axis mode, 2. The method for controlling a direct drive system according to claim 1, wherein, when the movable element moves to a position directly opposite the second winding, the first actuator is in the slave axis mode and the second actuator is in the master axis mode.

4. 4. The method for controlling a direct drive system according to claim 3, wherein the directions of the driving forces generated in the magnetic steel of the same mover by the first actuator and the second actuator are the same.

5. 4. The method for controlling a direct drive system according to claim 3, wherein the actuators corresponding to the first stator and the second stator are connected to the same controller, and the controller performs overall control of switching the drive mode for each actuator.

6. 2. The method for controlling a direct drive system according to claim 1, wherein the controller calculates absolute position information of the movable element moving on the guide rail based on the position information.

7. 2. The method of claim 1, wherein the first position feedback device is a read head, the second position feedback device is a grid ruler, and the read head is disposed directly opposite the grid ruler.

8. 1. A computing device comprising: A computer device comprising: a memory; a processor; and a computer program stored in the memory and executable by the processor, wherein, when the processor executes the computer program, steps in the method for controlling a direct drive system according to any one of claims 1 to 7 are realized.

9. 1. A computer-readable storage medium, comprising: The computer-readable storage medium has a computer program stored therein, and when the computer program is executed by a processor, steps in the method for controlling a direct drive system according to any one of claims 1 to 7 are performed.

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