An asynchronous control system and method for a multi-mover linear motor

Abstract

The application relates to an asynchronous control system and method of a multi-mover linear motor. The system is applied to a multi-mover linear motor which comprises a stator and a plurality of movers, and the stator is arranged in a same linear direction by splicing a plurality of stator modules, the stator module comprises a stator core and a stator winding, the stator winding is wound on a stator core tooth of the stator core and the head and tail lines are led out, one stator winding and one stator core tooth form a power supply unit, the asynchronous control system comprises a position detection unit, a linear motor driver and a linear motor motion controller, and the linear motor driver is correspondingly arranged with the stator module in the multi-mover linear motor. By using the system, when the multi-mover moves relative to the stator, the corresponding power supply unit of the stator winding coupled to the mover at present can be independently powered and driven by a multi-phase H-bridge circuit, so that the asynchronous control of the multi-mover is realized, the system loss is reduced, and the production line capacity and transportation efficiency are improved.

Description

Technical Field

[0001] This application relates to the field of linear motor control technology, and in particular to an asynchronous control system and method for a multi-motor linear motor. Background Technology

[0002] For long-distance moving-magnet permanent magnet linear motors, if a single controller is used to control the entire distance, the stator windings need to be energized during the motor's operation, as the mover travels from one end to the other. However, only the part coupled between the mover and stator is active; most of the energization only generates heat loss and does not affect the mover's operation, resulting in extremely low system efficiency. Furthermore, multiple movesrs can only be controlled synchronously, not asynchronously. For workstations on the production line with different working times, the production line's cycle time must meet the maximum workstation's working time, and the distance between workstations must be set as a multiple of the minimum workstation distance to ensure the mover reaches the correct workstation in one or more cycles. This will reduce the production line's capacity and transportation efficiency. If multiple stator segments are spliced ​​together, each stator segment is controlled by a driver. Although each segment can be controlled independently, the movers within the segment cannot be controlled asynchronously. For multiple movers, if asynchronous control is required, the movers must be assigned to different segments. Moreover, the asynchronous operation of the movers requires crossing segments, which requires transition segments. Therefore, to achieve asynchronous control, the distance between the movers needs to span a segment gap. The number of movers that can run on the production line will be limited, resulting in reduced production capacity. Summary of the Invention

[0003] Therefore, it is necessary to provide an asynchronous control system and method for multi-motor linear motors that can achieve asynchronous control of multiple motors, reduce losses, and improve production line capacity and transportation efficiency, in order to address the above-mentioned technical problems.

[0004] An asynchronous control system for a multi-moving linear motor, the multi-moving linear motor including a stator and several moving parts, the stator and moving parts being arranged opposite each other and maintaining a fixed gap, the moving parts moving relative to the stator while maintaining the gap;

[0005] The stator is composed of several stator modules spliced ​​together along the same straight line. The stator module includes a stator core and a stator winding. The stator core includes several stator core teeth and a magnetic yoke. The stator winding is wound on the stator core teeth, and the start and end wires of the stator winding are led out. One stator core tooth and one stator winding form a power supply unit. Several power supply units are installed on the magnetic yoke.

[0006] The mover consists of a back iron and permanent magnets, with the permanent magnets attached to the back iron in an alternating N and S pole arrangement;

[0007] The asynchronous control system includes: several position detection units, several linear motor drivers, and a linear motor motion controller; wherein the number of position detection units is the same as the number of linear motor drivers, and one linear motor driver is configured to correspond to one stator module of a multi-moving linear motor; the position detection units are connected to the linear motor drivers, and all linear motor drivers are connected to the linear motor motion controller through a communication bus;

[0008] The position detection unit is used to detect the position of several movers on the multi-motor linear motor and send the real-time position of each mover to the linear motor driver. The real-time position information is then transmitted to the linear motor motion controller via the communication bus.

[0009] The linear motor motion controller is used to obtain the real-time position of each mover and calculate the movement speed of the mover. Based on the movement speed and real-time position of the mover, it calculates the position and number of the stator windings currently coupled to each mover, and controls the linear motor driver to output drive voltage to the power supply unit corresponding to the stator winding currently coupled to each mover, and controls the magnitude, frequency and phase of the drive voltage.

[0010] The linear motor driver is used to connect to the power supply unit corresponding to the stator winding currently coupled to each mover through its multi-phase H-bridge circuit and output drive voltage, thereby asynchronously controlling the thrust and speed of each mover through the drive voltage.

[0011] In one embodiment, the asynchronous control system further includes: the minimum spacing between movers is twice the stator tooth width.

[0012] In one embodiment, the asynchronous control system further includes: permanent magnets arranged with alternating N and S poles and attached to the back iron in a straight pole manner or a skewed pole manner.

[0013] In one embodiment, the asynchronous control system further includes a metal block of a fixed size mounted on the mover.

[0014] In one embodiment, the asynchronous control system further includes: a position detection unit comprising a transmitting coil, a first receiving coil, and a second receiving coil mounted on a PCB board, the PCB board being mounted on the stator, the transmitting coil being used to transmit electromagnetic waves through an LC resonant circuit, and the first receiving coil and the second receiving coil being used to receive electromagnetic waves and output induced voltages of different amplitudes and phases.

[0015] In one embodiment, the asynchronous control system further includes: the position detection unit is also used to shield the electromagnetic waves emitted by the transmitting coil by a metal block mounted on the moving part when the moving part moves continuously relative to the stator, change the magnitude of the electromagnetic waves received by the first receiving coil and the second receiving coil, obtain the induced voltages with different amplitudes and phases output by the first receiving coil and the second receiving coil, and determine the real-time position of the metal block, i.e., determine the real-time position of the moving part, based on the induced voltage.

[0016] In one embodiment, the asynchronous control system further includes a first receiving coil and a second receiving coil that are sinusoidal in shape and offset from each other by 90°.

[0017] In one embodiment, the asynchronous control system further includes: the number of multiphase H-bridge circuits in the linear motor driver is the same as the number of power supply units in the stator module.

[0018] In one embodiment, the asynchronous control system further includes: the linear motor motion controller is also configured to, when the mover is moving continuously, control the linear motor driver to de-energize the power supply unit corresponding to a stator winding that is about to be decoupled, according to the direction of movement of the mover, and control the linear motor driver to pre-energize the power supply unit corresponding to a stator winding that is about to be coupled.

[0019] An asynchronous control method for a multi-moving linear motor, the multi-moving linear motor including a stator and several moving parts, the stator and moving parts being arranged opposite each other and maintaining a fixed gap, the moving parts moving relative to the stator while maintaining the gap;

[0020] The stator is composed of several stator modules spliced ​​together along the same straight line. The stator module includes a stator core and a stator winding. The stator core includes several stator core teeth and a magnetic yoke. The stator winding is wound on the stator core teeth, and the start and end wires of the stator winding are led out. One stator core tooth and one stator winding form a power supply unit. Several power supply units are installed on the magnetic yoke.

[0021] The mover consists of a back iron and permanent magnets, with the permanent magnets attached to the back iron in an alternating N and S pole arrangement;

[0022] Asynchronous control methods include the following steps:

[0023] The number of linear motor drivers and position detection units are configured according to the number of stator modules in the multi-movement linear motor. The position detection units are connected to the linear motor drivers, and all linear motor drivers are connected to a linear motor motion controller through a communication bus.

[0024] The position detection unit detects the position of several movers on the multi-motor linear motor and sends the real-time position of each mover to the linear motor driver. The real-time position information is then transmitted to the linear motor motion controller via the communication bus.

[0025] The linear motor motion controller obtains the real-time position of each mover and calculates the movement speed of the mover. Based on the movement speed and real-time position of the mover, it calculates the position and number of the stator windings currently coupled to each mover, and controls the linear motor driver to output drive voltage to the power supply unit corresponding to the stator winding currently coupled to each mover, and controls the magnitude, frequency and phase of the drive voltage.

[0026] The linear motor driver connects the multiphase H-bridge circuit to the power supply unit corresponding to the stator winding currently coupled to each mover and outputs a drive voltage. The thrust and speed of each mover are asynchronously controlled by the drive voltage.

[0027] The aforementioned asynchronous control system for a multi-movement linear motor is applied to a multi-movement linear motor, which includes a stator and multiple movers. The stator is composed of several stator modules arranged along the same straight line. Each stator module includes a stator core and stator windings. The stator windings are wound on the stator core teeth with the head and tail wires leading out. One stator winding and one stator core tooth constitute a power supply unit. The asynchronous control system includes a position detection unit, a linear motor driver, and a linear motor motion controller, with the linear motor driver corresponding to the stator modules in the multi-movement linear motor. When a mover moves relative to the stator, the position detection unit detects the real-time position of the mover, and the linear motor motion controller obtains the position and number of stator windings currently coupled to each mover based on the real-time position and the calculated movement speed of the mover. The controller then controls the multi-phase H-bridge circuit in the linear motor driver to output drive voltage to the power supply unit corresponding to the stator winding currently coupled to each mover, thereby asynchronously controlling the thrust and speed of each mover through the drive voltage. This system allows for the reasonable arrangement of multiple movers based on the number of workstations on the production line. When multiple movers move relative to the stator, the multi-phase H-bridge circuit provides independent power supply to the power supply unit corresponding to the stator winding currently coupled to the mover, thereby achieving asynchronous control of multiple movers, reducing system losses, and improving the production capacity and transportation efficiency of the production line. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the stator structure in one embodiment;

[0029] Figure 2 This is a schematic diagram of the power supply unit in one embodiment;

[0030] Figure 3This is a schematic diagram of the asynchronous control system for a multi-motor linear motor in one embodiment;

[0031] Figure 4 This is a schematic diagram of the mover structure in one embodiment; Figure 4 (a) is a schematic diagram of the mover structure when the permanent magnet is arranged with alternating N and S poles and attached to the back iron in a direct pole manner; Figure 4 (b) Schematic diagram of the mover structure when the permanent magnets are arranged with alternating N and N poles and attached to the back iron in a skewed manner;

[0032] Figure 5 This is a schematic diagram of the position detection unit in one embodiment;

[0033] Figure 6 This is a flowchart illustrating an asynchronous control method for a multi-moving linear motor in one embodiment.

[0034] Figure labels: Stator 1, Stator module 11, Stator core teeth 12, Stator winding 13, Magnetic yoke 14, Mover 2, Back iron 21, Permanent magnet 22, Position detection unit 3, PCB board 31, Transmitting coil 32, First receiving coil 33, Second receiving coil 34, Metal block 35. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0036] In one embodiment, such as Figures 1-5 As shown, this application provides an asynchronous control system for a multi-moving linear motor. The system is applied to a multi-moving linear motor, which includes a stator and several moving parts. The stator and moving parts are arranged opposite each other and maintain a fixed gap. The moving parts move relative to the stator while maintaining the gap.

[0037] The stator 1 is composed of several stator modules 11 spliced ​​together along the same straight line. The stator module 11 includes a stator core and a stator winding 13. The stator core includes several stator core teeth 12 and a magnetic yoke 14. The stator winding 13 is wound on the stator core teeth 12, and the head and tail wires of the stator winding 13 are led out. One stator core tooth 12 and one stator winding 13 form a power supply unit. Several power supply units are installed on the magnetic yoke 14.

[0038] The mover 2 includes a back iron 21 and a permanent magnet 22, which is attached to the back iron in an alternating N-S pole arrangement;

[0039] The asynchronous control system includes: several position detection units 3, several linear motor drivers, and a linear motor motion controller; wherein, the number of position detection units 3 is the same as the number of linear motor drivers, and one linear motor driver is configured to correspond to one stator module of a multi-moving linear motor; the position detection units 3 are connected to the linear motor drivers, and all linear motor drivers are connected to the linear motor motion controller through a communication bus (ethercat);

[0040] The position detection unit 3 is used to detect the position of several movers on the multi-motor linear motor and send the real-time position of each mover to the linear motor motion driver. The real-time position information is then transmitted to the linear motor motion controller via the communication bus.

[0041] The linear motor motion controller is used to obtain the real-time position of each mover and calculate the movement speed of the mover. Based on the movement speed and real-time position of the mover, it calculates the position and number of the stator windings currently coupled to each mover, and controls the linear motor driver to output drive voltage to the power supply unit corresponding to the stator winding currently coupled to each mover, and controls the magnitude, frequency and phase of the drive voltage.

[0042] The linear motor driver is used to connect to the power supply unit corresponding to the stator winding currently coupled to each mover through its multi-phase H-bridge circuit and output drive voltage, thereby asynchronously controlling the thrust and speed of each mover through the drive voltage.

[0043] Furthermore, the linear motor driver includes an AC / DC rectifier circuit, a soft-start circuit, fault detection and protection circuits for overcurrent, overvoltage, undervoltage, and overheating, an H-bridge drive circuit, a main control unit, and a communication unit. Each H-bridge drive circuit is independently connected to a power supply unit in the stator, and all H-bridge drive circuits are connected to the main control unit via a communication bus. The main control unit issues commands through the communication bus to instruct each H-bridge drive circuit to output a drive voltage to the stator winding corresponding to the power supply unit; the amplitude, frequency, and phase of this voltage are all controlled by the main control unit. By controlling their amplitude, frequency, and phase, the main control unit achieves thrust and speed control for each mover.

[0044] It is understandable that, because each power supply unit in the stator is independently controlled, when the mover crosses different stator modules, the power supply unit corresponding to the stator winding currently coupled to the mover can be independently powered according to the multi-phase H-bridge circuits in the two linear motor drivers configured for the two stator modules being crossed. No transition section is needed during the crossing process, and the number of movers on the production line is unlimited, thus increasing the system's productivity. Furthermore, because each power supply unit is independently powered, there is no need to consider other uncoupled stator windings when driving the mover, reducing unnecessary heat loss in the motor and improving the system's power supply efficiency.

[0045] In one embodiment, the minimum spacing between the movers is twice the width of the stator tooth slot.

[0046] In one embodiment, such as Figure 4 (a) and Figure 4 As shown in (b), the permanent magnets 22 are arranged with alternating N and N poles and are attached to the back iron 21 in a straight pole or oblique pole manner. The width of the multiple movers 2 is the same, and their lengths can be the same or different.

[0047] In one embodiment, such as Figure 5 As shown, a metal block 35 of a fixed size is installed on the mover.

[0048] In one embodiment, such as Figure 5 As shown, the position detection unit 3 includes a transmitting coil 32, a first receiving coil 33, and a second receiving coil 34 mounted on a PCB board 31. The PCB board 31 is mounted on the stator. The transmitting coil 32 is used to transmit electromagnetic waves through an LC resonant circuit. The first receiving coil 33 and the second receiving coil 34 are used to receive electromagnetic waves and output induced voltages of different amplitudes and phases. Furthermore, the first receiving coil 33 and the second receiving coil 34 are sinusoidal in shape and offset from each other by 90°.

[0049] The position detection unit 3 is also used to shield the electromagnetic waves emitted by the transmitting coil 32 by the metal block 35 installed on the moving part when the moving part moves continuously relative to the stator, change the magnitude of the electromagnetic waves received by the first receiving coil 33 and the second receiving coil 34, obtain the induced voltages with different amplitudes and phases output by the first receiving coil 44 and the second receiving coil 34, and determine the real-time position of the metal block 35, i.e., the real-time position of the moving part, based on the induced voltage.

[0050] In one embodiment, the number of multiphase H-bridge circuits in the linear motor driver is the same as the number of power supply units in the stator module. Specifically, the number of multiphase H-bridge circuits in a linear motor driver is determined by the design capacity of the linear motor driver, and is generally the same as the number of power supply units in the stator module. One stator module is equipped with one linear motor driver, and several linear motor drivers combined with several stator modules can meet the mover movement distance requirements of different line lengths.

[0051] In one embodiment, the linear motor motion controller is further configured to, when the mover continues to move, control the linear motor driver to de-energize the power supply unit corresponding to a stator winding that is about to be decoupled, according to the direction of the mover's movement, and control the linear motor driver to pre-energize the power supply unit corresponding to a stator winding that is about to be coupled.

[0052] In one embodiment, when the multi-mover linear motor runs asynchronously at each workstation, the interval between each workstation on the production line is set according to the site and equipment requirements, and the running speed, start-stop time and waiting time of the mover are determined according to the workstation's working time.

[0053] In one embodiment, for workstations with long working times, the number of workstations can be increased and multiple movers can be arranged continuously at the minimum interval of the movers to complete the work at the same workstation, thereby reducing the working time of the production line at a certain workstation and improving the efficiency of the production line.

[0054] In one embodiment, the asynchronous control system of the multi-moving linear motor described above can achieve asynchronous control as well as synchronous control.

[0055] In one embodiment, such as Figure 6 As shown, an asynchronous control method for a multi-moving linear motor is provided. The method is applied to a multi-moving linear motor, which includes a stator and several moving parts. The stator and moving parts are arranged opposite each other and maintain a fixed gap. The moving parts move relative to the stator while maintaining the gap.

[0056] The stator is composed of several stator modules spliced ​​together along the same straight line. The stator module includes a stator core and a stator winding. The stator core includes several stator core teeth and a magnetic yoke. The stator winding is wound on the stator core teeth, and the start and end wires of the stator winding are led out. One stator core tooth and one stator winding form a power supply unit. Several power supply units are installed on the magnetic yoke.

[0057] The mover consists of a back iron and permanent magnets, with the permanent magnets attached to the back iron in an alternating N and S pole arrangement;

[0058] Asynchronous control methods include the following steps:

[0059] Step S1: Configure the same number of linear motor drivers and position detection units according to the number of stator modules in the multi-moving linear motor. The position detection units are connected to the linear motor drivers, and all linear motor drivers are connected to a linear motor motion controller through a communication bus.

[0060] Step S2: The position detection unit detects the position of several moving parts on the multi-moving linear motor and sends the real-time position of each moving part to the linear motor motion driver. The real-time position information is then transmitted to the linear motor motion controller via the communication bus.

[0061] Step S3: The real-time position of each mover is obtained through the linear motor motion controller and the movement speed of the mover is calculated. Based on the movement speed and real-time position of the mover, the position and number of the stator windings currently coupled to each mover are obtained. The linear motor driver is controlled to output the driving voltage to the power supply unit corresponding to the stator winding currently coupled to each mover, and the magnitude, frequency and phase of the driving voltage are controlled.

[0062] Step S4: Connect the multiphase H-bridge circuit in the linear motor driver to the power supply unit corresponding to the stator winding currently coupled to each mover and output the drive voltage. Asynchronously control the thrust and speed of each mover through the drive voltage.

[0063] It should be understood that, although Figure 6 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 6 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed 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 some of the sub-steps or stages of other steps.

[0064] The technical features of the above embodiments can be combined in any way. For the sake of brevity, 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.

[0065] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these modifications and improvements all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An asynchronous control system for a multi-moving linear motor, characterized in that, The multi-moving linear motor includes a stator and several moving parts. The stator and moving parts are arranged opposite each other and maintain a fixed gap. The moving parts move relative to the stator while maintaining the gap. A metal block of a fixed size is mounted on the moving parts. The stator is composed of several stator modules spliced ​​together along the same straight line. Each stator module includes a stator core and a stator winding. The stator core includes several stator core teeth and a magnetic yoke. The stator winding is wound on the stator core teeth, and the start and end wires of the stator winding are led out. One stator core tooth and one stator winding constitute a power supply unit. Several power supply units are installed on the magnetic yoke. The mover includes a back iron and a permanent magnet, wherein the permanent magnet is attached to the back iron in an alternating N-S pole arrangement; The asynchronous control system includes: a plurality of position detection units, a plurality of linear motor drivers, and a linear motor motion controller; wherein the number of position detection units is the same as the number of linear motor drivers, and one linear motor driver is configured to correspond to one stator module of the multi-moving linear motor; the position detection units are connected to the linear motor drivers, and all linear motor drivers are connected to the linear motor motion controller through a communication bus; The position detection unit is used to detect the position of several movers on the multi-motor linear motor and send the real-time position of each mover to the linear motor driver. The real-time position information is then transmitted to the linear motor motion controller via a communication bus. The position detection unit includes a transmitting coil, a first receiving coil, and a second receiving coil mounted on a PCB board. The PCB board is mounted on the stator. The transmitting coil transmits electromagnetic waves through an LC resonant circuit. The first and second receiving coils receive the electromagnetic waves and output induced voltages of different amplitudes and phases. The position detection unit is also used to shield the electromagnetic waves emitted by the transmitting coil by a metal block mounted on the mover when the mover moves continuously relative to the stator. This changes the magnitude of the electromagnetic waves received by the first and second receiving coils, allowing the acquisition of induced voltages of different amplitudes and phases output by the first and second receiving coils. Based on the induced voltages, the real-time position of the metal block is calculated, thus determining the real-time position of the mover. The linear motor motion controller is used to acquire the real-time position of each mover and calculate the movement speed of the mover. Based on the movement speed and real-time position of the mover, it calculates the position and number of the stator windings currently coupled to each mover, and controls the linear motor driver to output driving voltage to the power supply unit corresponding to the stator windings currently coupled to each mover, and controls the magnitude, frequency and phase of the driving voltage. The linear motor driver is used to connect to the power supply unit corresponding to the stator winding currently coupled to each mover through the multi-phase H-bridge circuit therein and output a drive voltage, thereby asynchronously controlling the thrust and speed of each mover through the drive voltage.

2. The asynchronous control system according to claim 1, characterized in that, The minimum spacing between the moving parts is twice the width of the stator tooth groove.

3. The asynchronous control system according to claim 1, characterized in that, The permanent magnets are arranged with alternating N and S poles and are attached to the back iron in a straight or oblique manner.

4. The asynchronous control system according to claim 1, characterized in that, The first receiving coil and the second receiving coil are sinusoidal in shape and offset from each other by 90°.

5. The asynchronous control system according to claim 1, characterized in that, The number of multiphase H-bridge circuits in the linear motor driver is the same as the number of power supply units in the stator module.

6. The asynchronous control system according to claim 1, characterized in that, The linear motor motion controller is also used to, when the mover is moving continuously, control the linear motor driver to cut off the power supply unit corresponding to a stator winding that is about to be decoupled according to the direction of the mover's movement, and control the linear motor driver to pre-energize the power supply unit corresponding to a stator winding that is about to be coupled.

7. An asynchronous control method for a multi-moving linear motor, characterized in that, The multi-moving linear motor includes a stator and several moving parts. The stator and moving parts are arranged opposite each other and maintain a fixed gap. The moving parts move relative to the stator while maintaining the gap. A metal block of a fixed size is mounted on the moving parts. The stator is composed of several stator modules spliced ​​together along the same straight line. Each stator module includes a stator core and a stator winding. The stator core includes several stator core teeth and a magnetic yoke. The stator winding is wound on the stator core teeth, and the start and end wires of the stator winding are led out. One stator core tooth and one stator winding constitute a power supply unit. Several power supply units are installed on the magnetic yoke. The mover includes a back iron and a permanent magnet, wherein the permanent magnet is attached to the back iron in an alternating N-S pole arrangement; The asynchronous control method includes the following steps: The same number of linear motor drivers and position detection units are configured according to the number of stator modules in the multi-moving linear motor. The position detection units are connected to the linear motor drivers, and all linear motor drivers are connected to a linear motor motion controller through a communication bus. The position detection unit detects the positions of several movers on the multi-motor linear motor and sends the real-time positions of each mover to the linear motor driver. The real-time position information is then transmitted to the linear motor motion controller via a communication bus. The position detection unit includes a transmitting coil, a first receiving coil, and a second receiving coil mounted on a PCB board. The PCB board is mounted on the stator. The transmitting coil transmits electromagnetic waves through an LC resonant circuit. The first and second receiving coils receive the electromagnetic waves and output induced voltages of different amplitudes and phases. The position detection unit also shields the electromagnetic waves emitted by the transmitting coil when the movers move continuously relative to the stator by using a metal block mounted on the movers. This changes the magnitude of the electromagnetic waves received by the first and second receiving coils, allowing the acquisition of induced voltages of different amplitudes and phases output by the first and second receiving coils. Based on these induced voltages, the real-time position of the metal block is calculated, thus determining the real-time position of the movers. The linear motor motion controller obtains the real-time position of each mover and calculates the movement speed of the mover. Based on the movement speed and real-time position of the mover, it calculates the position and number of stator windings currently coupled to each mover, and controls the linear motor driver to output drive voltage to the power supply unit corresponding to the stator winding currently coupled to each mover, and controls the magnitude, frequency and phase of the drive voltage. The linear motor driver connects the multiphase H-bridge circuit to the power supply unit corresponding to the stator winding currently coupled to each mover and outputs a drive voltage. The thrust and speed of each mover are asynchronously controlled by the drive voltage.

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