Planar motor and working method
By improving the combination of the mover permanent magnet and the winding design, the problems of current distortion and torque fluctuation when the mover rotates around the Z-axis of the planar motor were solved, achieving more stable operation and lower current frequency requirements, thus improving the motor's operating performance.
Patent Information
- Application Number
- CN202511961917.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-24
- Publication Date
- 2026-03-17
AI Technical Summary
Existing multi-degree-of-freedom planar motors are prone to current waveform distortion and large torque fluctuations when the mover rotates around the Z-axis, which affects the smooth operation of the mover.
The moving permanent magnet combination method is adopted in which the magnetization directions of two adjacent small permanent magnets in each group are perpendicular to each other, and they are rotated 90° clockwise in sequence. They are formed into a rectangular plate structure through the Heilbeck array. Combined with the three-phase distributed winding design of X and Y windings, the air gap is adjusted to control the current frequency and phase difference, so as to realize the operation of two-phase motor.
It reduces current waveform distortion, lowers torque ripple, improves the operating stability of the mover and the current tracking capability of the controller, and reduces electromagnetic torque ripple by 30%.
Smart Images
Figure CN121689716A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of motor technology, specifically to a planar motor and its operating method. Background Technology
[0002] Existing multi-degree-of-freedom planar motor products (such as B&R ACOPOS 6D, Beckhoff XPlanar, etc.) have electromagnetic structures such as Figure 1 As shown, it includes a mover 1 and a stator 2. The mover 1 includes a first group of permanent magnets 11, a second group of permanent magnets 12, a third group of permanent magnets 13, and a fourth group of permanent magnets 14. Each of the four groups of permanent magnets consists of five small permanent magnets, and the magnetization directions of the four groups of permanent magnets are all the same. The width of each of the four groups of permanent magnets is half its length, and the four groups of permanent magnets are arranged counterclockwise on the mover 1, making the mover 1 square in shape. The stator 2 includes an X-winding 21 laid along the X-axis and a Y-winding 22 laid along the Y-axis. Both the X-winding 21 and the Y-winding 22 are three-phase distributed windings, and the pole pitch of the windings is the same as half the width of the four groups of permanent magnets (i.e., as shown in the diagram). Figure 1 In the positions shown, each group of permanent magnets is aligned with the six coil edges of the three-phase coil. The winding coil aligned with the first group of permanent magnets 11 is denoted as X1, the winding coil aligned with the second group of permanent magnets 12 as Y1, the winding coil aligned with the third group of permanent magnets 13 as X2, and the winding coil aligned with the fourth group of permanent magnets 14 as Y2. It should be noted that the specific coils corresponding to X1, Y1, X2, and Y2 will change as the mover 1 moves.
[0003] When the mover moves linearly along the Y-axis, the direction of movement is parallel to the laying direction of the Y-winding 22, meaning there is no changing magnetic flux in the Y-winding 22. Therefore, the Y-winding 22 will not interact with the mover to generate electromagnetic thrust or torque. However, the linear movement of the mover along the Y-axis will cause a change in the magnetic flux in the X-winding 21. The waveforms of the three-phase magnetic flux in the X1 and X2 coils as the mover position changes are as follows: Figure 2 As shown. The flux linkage amplitudes and phases in both sets of coils are the same, and both are symmetrical three-phase waveforms. Performing a Parker transform on the three-phase flux linkage waveforms yields the D-axis flux linkage waveform in the synchronous coordinate system, as shown below. Figure 3 As shown, the D-axis flux linkage of both sets of coils is a constant DC current. Therefore, it is only necessary to pass a constant Q-axis current (such as...) through both sets of coils. Figure 4 As shown in the figure, a constant electromagnetic thrust can be generated. For example... Figure 1 and Figure 5 As shown, the electromagnetic thrust F1 generated by coil X1 and the electromagnetic thrust F3 generated by coil X2 are of the same magnitude and direction, and the net force on the mover is F1 + F3. Furthermore, since the points of application of F1 and F3 are located on either side of the center point O of the mover, therefore... Figure 6As shown, the electromagnetic torques generated by F1 and F3 are equal in magnitude and opposite in direction, canceling each other out, resulting in a net torque of zero on the mover. This ensures that the mover is only subjected to electromagnetic thrust in the Y direction, allowing for stable operation. The same principle applies when the mover moves linearly along the X-axis.
[0004] When the mover 1 rotates around the Z-axis, the magnetic flux linkages in both the X winding 21 and the Y winding 22 will change. The waveforms of the three-phase magnetic flux linkages in the X1, X2, Y1, and Y2 coils as the mover position changes are as follows: Figure 7 As shown. Taking coil X1 as an example, the waveform analysis shows that its three-phase waveform exhibits unidirectional periodic fluctuations with a period of 90°, and the maximum / minimum values and Figure 2 The values at the 0° position correspond to the values at the midpoint. The same applies to the other three groups of coils. Furthermore, the magnetic flux linkages of all four groups of coils are in phase. Performing a Parker transform, the D-axis magnetic flux linkage waveforms of the four groups of coils are as follows: Figure 8 As shown, their waveforms (including phase) are completely identical, the motor degenerates into a single-phase motor, and the primary component of the D-axis flux linkage is the fourth harmonic. To generate positive electromagnetic torque, current is supplied to the four sets of coils as follows: Figure 9 The Q-axis current shown also has a primary component that is the fourth harmonic, which places high demands on the controller's current tracking capability and can easily lead to waveform distortion. Assuming the current waveform remains undistorted, the resulting electromagnetic thrust would be as follows: Figure 10 As shown. Since the flux linkage waveforms of coils X1 and X2 are the same, but their current waveforms are completely opposite, the resulting electromagnetic thrusts F1 and F3 are completely opposite and cancel each other out. The same applies to coils Y1 and Y2, making the net electromagnetic thrust on the mover zero. The torque waveform on the mover is shown below. Figure 11 As shown, since the points of action of F1 and F3 are located on both sides of the center point O of the mover, the electromagnetic torque waveforms generated by F1 and F3 are exactly the same and superimposed on each other. The same applies to F2 and F4. Furthermore, the electromagnetic torque waveforms generated by the X winding 21 and the Y winding 22 are also exactly the same, thus generating a positive electromagnetic torque. However, in addition to the positive DC component, this electromagnetic torque also has a huge harmonic component (the harmonic components of the electromagnetic torque generated by each group of coils are exactly the same and cannot be canceled out), resulting in large fluctuations in the torque experienced by the mover, which seriously affects the smooth operation of the mover. Summary of the Invention
[0005] This invention provides a planar motor and its operating method, which can reduce the distortion of the current waveform when the mover rotates around the Z-axis and reduce the torque fluctuation of the mover.
[0006] The present invention provides the following technical solution: a planar motor, comprising a mover and a stator. The mover is formed by connecting two pairs of permanent magnets (a first group, a second group, a third group, and a fourth group) perpendicularly end-to-end. The stator comprises an X-winding laid along the X-axis and a Y-winding laid along the Y-axis. Both the X-winding and the Y-winding are three-phase distributed windings, and the pole pitch of the windings is the same as half the width of the four groups of permanent magnets. The magnetization directions of the first and second groups of permanent magnets are the same, the magnetization directions of the third and fourth groups of permanent magnets are the same, and the magnetization directions of the first and third groups of permanent magnets are opposite.
[0007] As a further technical solution of the present invention, the first group of permanent magnets, the second group of permanent magnets, the third group of permanent magnets and the fourth group of permanent magnets are all rectangular plate-like structures formed by five small permanent magnets arranged in a Heilbeck array.
[0008] As a further technical solution of the present invention, in each group of permanent magnets, the magnetization directions of two adjacent small permanent magnets are perpendicular to each other, and the magnetization directions of the small permanent magnets are rotated 90° clockwise in sequence.
[0009] As a further technical solution of the present invention, there is an adjustable air gap between the mover and the stator.
[0010] As a further technical solution of the present invention, the X winding is located between the Y winding and the mover.
[0011] A method for operating a planar motor, applicable to the aforementioned planar motor, comprising:
[0012] When the mover moves linearly along the X-axis, a sinusoidal three-phase current with the same amplitude is passed into the winding coil Y1 of the stator aligned with the second set of permanent magnets and the winding coil Y2 of the stator aligned with the fourth set of permanent magnets, respectively. The phase difference of the same phase in the winding coils Y1 and Y2 is 180°, which makes the mover run smoothly.
[0013] When the mover moves linearly along the Y-axis, a sinusoidal three-phase current with the same amplitude is passed into the stator winding coil X1, which is aligned with the first set of permanent magnets, and the stator winding coil X2, which is aligned with the third set of permanent magnets. The phase difference of the same phase in winding coil X1 and winding coil X2 is 180°, which makes the mover run smoothly.
[0014] When the mover rotates along the Z-axis, sinusoidal three-phase currents are respectively passed into the stator winding coil X1 aligned with the first group of permanent magnets and the stator winding coil X2 aligned with the third group of permanent magnets. The phase difference between the same phase of winding coil X1 and winding coil X2 is 180°. Sinusoidal three-phase currents are respectively passed into the stator winding coil Y1 aligned with the second group of permanent magnets and the stator winding coil Y2 aligned with the fourth group of permanent magnets. The phase difference between the same phase of winding coil Y1 and winding coil Y2 is 180°.
[0015] The present invention has the following beneficial effects:
[0016] When the mover rotates around the Z-axis, the primary component of the winding flux linkage becomes a low-frequency harmonic, meaning the required current frequency decreases. This helps reduce distortion in the current waveform. Furthermore, the two windings have a 90° phase difference, and since the motor is a two-phase motor, the torque fluctuations generated by each winding can partially cancel each other out, ultimately suppressing mover torque fluctuations. Simultaneously, when the mover moves linearly along the X and Y axes, three-phase currents of corresponding amplitudes are supplied to the windings, maintaining performance similar to existing motors. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the electromagnetic structure of an existing motor;
[0018] Figure 2 A schematic diagram of the three-phase flux linkage waveforms during the linear motion of the rotor of an existing motor.
[0019] Figure 3 A schematic diagram of the D-axis flux linkage waveform during the linear motion of the existing motor's rotor.
[0020] Figure 4 This is a schematic diagram of the Q-axis current waveform during the linear motion of the existing motor's rotor;
[0021] Figure 5 This is a schematic diagram of the force waveform of the rotor during linear motion of an existing motor.
[0022] Figure 6 This is a schematic diagram of the torque waveform of the rotor when the rotor of an existing motor is in linear motion.
[0023] Figure 7 A schematic diagram of the three-phase flux linkage waveforms during the rotation of the rotor of an existing motor.
[0024] Figure 8 This is a schematic diagram of the D-axis flux linkage waveform during the rotational motion of an existing motor's rotor.
[0025] Figure 9 This is a schematic diagram of the Q-axis current waveform when the rotor of an existing motor rotates.
[0026] Figure 10 This is a schematic diagram of the force waveform of the rotor when the rotor of an existing motor rotates.
[0027] Figure 11 This is a schematic diagram of the torque waveform experienced by the rotor during the rotational motion of an existing motor.
[0028] Figure 12 This is a schematic diagram of the planar motor of the present invention;
[0029] Figure 13 This is a schematic diagram of the three-phase flux linkage waveform during the linear motion of the motor mover of the present invention;
[0030] Figure 14 This is a schematic diagram of the D-axis flux linkage waveform during the linear motion of the motor mover of the present invention;
[0031] Figure 15 This is a schematic diagram of the Q-axis current waveform during the linear motion of the motor mover of the present invention;
[0032] Figure 16 This is a schematic diagram of the force waveform of the motor rotor during linear motion.
[0033] Figure 17 This is a schematic diagram of the torque waveform experienced by the motor rotor during linear motion.
[0034] Figure 18 This is a schematic diagram of the three-phase magnetic flux waveform during the rotational motion of the motor mover of the present invention;
[0035] Figure 19 This is a schematic diagram of the D-axis magnetic flux waveform during the rotational motion of the motor mover of the present invention;
[0036] Figure 20 This is a schematic diagram of the Q-axis current waveform during the rotational motion of the motor mover of the present invention;
[0037] Figure 21 This is a schematic diagram of the force waveform of the motor rotor during its rotational motion.
[0038] Figure 22 This is a schematic diagram of the torque waveform experienced by the motor rotor during its rotational motion.
[0039] Figure 23 This is a schematic diagram of the total torque waveform of the motor and the existing motor during the rotational motion of the motor in this invention;
[0040] Figure 24 This is a schematic diagram of the permanent magnet pole distribution in an existing electric motor.
[0041] Figure 25 This is a schematic diagram of the magnetic pole distribution of the permanent magnet in this invention;
[0042] Figure 26 This is a schematic diagram of the three-phase current waveforms when the rotor of an existing motor is in linear motion.
[0043] Figure 27 This is a schematic diagram of the three-phase current waveforms during the linear motion of the motor rotor in this invention;
[0044] Figure 28 This is a schematic diagram of the three-phase current waveforms during the rotation of the motor rotor of the present invention.
[0045] In the diagram: 1. Mover; 11. First group of permanent magnets; 12. Second group of permanent magnets; 13. Third group of permanent magnets; 14. Fourth group of permanent magnets; 2. Stator; 21. X winding; 22. Y winding. Detailed Implementation
[0046] The technical solutions of the embodiments of this specification will be explained and described below with reference to the accompanying drawings. However, the following embodiments are only preferred embodiments of this specification and not all of them. Other embodiments obtained by those skilled in the art based on the embodiments in the implementation methods without creative effort are all within the protection scope of this specification.
[0047] In the description of this application, terms such as "front," "rear," "inner," "outer," "upper," "lower," "left," and "right" are used only to indicate orientation or positional relationship for the convenience of describing the embodiments and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this specification.
[0048] Please see Figure 12-23 As shown, a planar motor includes a mover 1 and a stator 2. The mover 1 is formed by connecting two pairs of permanent magnets 11, 12, 13, and 14 perpendicularly end to end. The stator 2 includes an X-winding 21 laid along the X-axis and a Y-winding 22 laid along the Y-axis. Both the X-winding 21 and the Y-winding 22 are three-phase distributed windings, and the pole pitch of the windings is the same as half the width of the four sets of permanent magnets. The magnetization directions of the first set of permanent magnets 11 and the second set of permanent magnets 12 are the same, the magnetization directions of the third set of permanent magnets 13 and the fourth set of permanent magnets 14 are the same, and the magnetization directions of the first set of permanent magnets 11 and the third set of permanent magnets 13 are opposite.
[0049] In the above scheme, when the mover 1 rotates around the Z-axis, the primary component of the winding flux linkage becomes a low-frequency harmonic, meaning the required current frequency is reduced. This helps to reduce the distortion of the current waveform. Furthermore, since the flux linkages of the two windings have a 90° phase difference, and the motor is a two-phase motor, the torque fluctuations generated by the two windings can partially cancel each other out, ultimately suppressing the torque fluctuations of the mover 1. Simultaneously, when the mover 1 moves linearly along the X and Y axes, three-phase currents of corresponding amplitudes are supplied to the windings, maintaining the same performance as existing motors.
[0050] Preferably, the first group of permanent magnets 11, the second group of permanent magnets 12, the third group of permanent magnets 13, and the fourth group of permanent magnets 14 are all rectangular plate-like structures formed by five small permanent magnets arranged in a Hellbeck array; in each group of permanent magnets, the magnetization directions of adjacent small permanent magnets are perpendicular to each other, and the magnetization directions of the small permanent magnets are rotated 90° clockwise sequentially; there is an adjustable air gap between the mover 1 and the stator 2; the X winding 21 is located between the Y winding 22 and the mover 1. Figure 25 As shown, this is a side view of each group of permanent magnets along its width, with the arrow pointing to the N pole. In the first group of permanent magnets 11 and the second group of permanent magnets 12, the magnetic poles of the two outermost small permanent magnets are S pole at the bottom and N pole at the top, i.e., the arrows point from bottom to top. In the third group of permanent magnets 13 and the fourth group of permanent magnets 14, the magnetic poles of the two outermost small permanent magnets are N pole at the bottom and S pole at the top, i.e., the arrows point from top to bottom.
[0051] A method for operating a planar motor, applicable to the aforementioned planar motor, comprising:
[0052] When the mover 1 moves linearly along the X-axis, a sinusoidal three-phase current with the same amplitude is passed into the winding coil Y1 of the stator 2 aligned with the second set of permanent magnets 12 and the winding coil Y2 of the stator 2 aligned with the fourth set of permanent magnets 14, respectively. The phase difference between the same phase of the winding coil Y1 and the winding coil Y2 is 180°, so that the mover 1 runs smoothly.
[0053] When the mover 1 moves linearly along the Y-axis, a sinusoidal three-phase current with the same amplitude is passed into the winding coil X1 of the stator 2 aligned with the first set of permanent magnets 11 and the winding coil X2 of the stator 2 aligned with the third set of permanent magnets 13, respectively. The phase difference between the same phase of the winding coil X1 and the winding coil X2 is 180°, which makes the mover 1 run smoothly.
[0054] according to Figure 26 The diagram shows the three-phase current waveforms of the existing motor's rotor 1 during linear motion. In the existing motor, when the rotor 1 moves linearly along the X-axis, the Y1 and Y2 three-phase coils of the Y winding 22 are supplied with sinusoidal three-phase currents of the same amplitude. The phase difference between any two phases is 120 degrees. The currents of the same phases of Y1 and Y2 (such as phase a of Y1 and phase a of Y2, phase b of Y1 and phase b of Y2, and phase c of Y1 and phase c of Y2) have the same amplitude and the same phase.
[0055] In the motor of the present invention, when the mover 1 moves linearly along the X-axis, the Y1 and Y2 three-phase coils of the Y winding 22 are supplied with sinusoidal three-phase currents of the same amplitude. The phase difference between any two phases of the current is 120 degrees. The current amplitudes of the same phases of Y1 and Y2 (such as phase a of Y1 and phase a of Y2, phase b of Y1 and phase b of Y2, phase c of Y1 and phase c of Y2) are the same, but the phases are 180 degrees apart.
[0056] The working principle of the planar motor in this invention is described in detail below.
[0057] Based on the position of the mover 1 on the stator 2, the winding coil aligned with the first group of permanent magnets 11 is denoted as X1, the winding coil aligned with the second group of permanent magnets 12 is denoted as Y1, the winding coil aligned with the third group of permanent magnets 13 is denoted as X2, and the winding coil aligned with the fourth group of permanent magnets 14 is denoted as Y2.
[0058] When the mover 1 moves linearly along the Y-axis, similar to existing motors, the Y-winding 22 does not interact with the mover 1 to generate electromagnetic thrust or torque, but the magnetic flux in the X-winding 21 will change. The waveforms of the three-phase magnetic flux in the X1 and X2 coils as the position of the mover 1 change are as follows: Figure 13 As shown. The flux linkage waveform of coil X1 is the same as that of the existing motor, while the flux linkage amplitude of coil X2 is the same as that of coil X1, but the phase difference is 180°. Performing a Parker transform on the three-phase flux linkage waveforms yields the D-axis flux linkage waveform in the synchronous coordinate system, as shown below. Figure 14 As shown, the D-axis flux linkages of both sets of coils are constant DC currents, but they are opposites of each other. Therefore, it is necessary to pass constant Q-axis currents (such as...) that are opposites of each other into the two sets of coils. Figure 15 (As shown). The electromagnetic thrust generated at this time is as follows: Figure 16 As shown, the electromagnetic thrust F1 generated by coil X1 and the electromagnetic thrust F3 generated by coil X2 are of the same magnitude and direction, and the resultant force on the mover 1 is F1 + F3. Meanwhile, since the points of application of F1 and F3 are located on either side of the center point O of the mover 1, therefore... Figure 17 As shown, the electromagnetic torques generated by coils F1 and X2 are equal in magnitude and opposite in direction, canceling each other out, resulting in zero net torque on rotor 1. This ensures that rotor 1 is only subjected to electromagnetic thrust in the Y direction, allowing for stable operation. The same principle applies when rotor 1 moves linearly along the X-axis.
[0059] When the mover 1 rotates around the Z-axis, the waveforms of the three-phase flux linkages in coils X1, X2, Y1, and Y2 as the position of the mover 1 changes are as follows: Figure 18 As shown. Except for phase A flux linkage, which is always 0, phases B and C flux linkage exhibit alternating periodic fluctuations with a period of 360°, and the maximum and minimum values are equal. This means that the main component of the flux linkage has changed from the DC component + 4th harmonic component of the existing motor to the 1st harmonic component. Furthermore, the flux linkage phases of the four coils differ. Performing a Parker transform, the D-axis flux linkage waveforms of the four coils are as follows... Figure 19 As shown, the waveforms X1, Y1, X2, and Y2 are 90° out of phase, so the motor can be considered a two-phase motor. The primary component of the D-axis flux linkage is the first harmonic, and the secondary components are the third and fifth harmonics. To generate positive electromagnetic torque, current is supplied to the four sets of coils as follows: Figure 20The Q-axis current shown has a primary component of the first harmonic, which is significantly lower than the frequency of existing motors. This reduces the requirements for the controller's current tracking capability and decreases the probability of current waveform distortion. Assuming the current waveform is undistorted, the generated electromagnetic thrust is as follows: Figure 21 As shown. Since the flux linkage waveforms of coils X1 and X2 are completely opposite, but their current waveforms are the same, the resulting electromagnetic thrusts F1 and F3 are completely opposite and cancel each other out. The same applies to coils Y1 and Y2, making the net electromagnetic thrust on rotor 1 zero. The torque waveform on rotor 1 is shown below. Figure 22 As shown, since the points of action of F1 and F3 are located on both sides of the center point O of the mover 1, the electromagnetic torque waveforms generated by F1 and F3 are exactly the same and superimposed on each other. The same applies to F2 and F4, thus generating a positive electromagnetic torque. It should be noted that since the D-axis flux linkage waveform contains 3rd and 5th harmonics, the electromagnetic torques generated by the X winding 21 and Y winding 22 respectively contain 2nd, 4th, and 6th harmonics. However, since the motor is equivalent to a two-phase motor, the 2nd harmonic electromagnetic torques generated by the two windings are 180° out of phase. Figure 22 The electromagnetic torque waveforms of the two windings differ, thus they can cancel each other out, resulting in no second harmonic in the total electromagnetic torque on mover 1, and the same applies to the sixth harmonic. The fourth harmonic electromagnetic torque generated by the two windings is in phase, resulting in a fourth harmonic in the total electromagnetic torque on mover 1. Therefore, electromagnetic torque fluctuations still exist, but the amplitude of the fluctuations has been significantly reduced. Figure 23 As shown, when the mover 1 rotates, the average total electromagnetic torque on the mover 1 of the existing motor is 1.50, and the peak-to-peak value of the fluctuation is 4.0. The average total electromagnetic torque on the mover 1 of the motor of the present invention is 1.36, and the peak-to-peak value of the fluctuation is 2.8. Compared with the existing motor, the electromagnetic torque fluctuation of the motor of the present invention is reduced by 30%, while the average value is reduced by only 9%.
[0060] like Figure 28 As shown, the current waveform in the abc three-phase coordinate system is as follows:
[0061] The three-phase currents of the X1 coil in the X winding 21 are all sinusoidal waves, with the same period as the Q-axis current, and their amplitudes are related to the position of the center point of the mover 1. For example, when the center point of the mover 1 is located at... Figure 27 At the 0 electrical angle position, the current in X1A is 1, the current in X1B is -0.5, and the current in X1C is -0.5. At this time, the mover 1 rotates, as shown... Figure 28As shown, the current amplitude of X1A is 1, and its phase is the same as the Q-axis current; the current amplitude of X1B is 0.5, but its phase differs from the Q-axis current by 180 degrees; the current amplitude of X1C is 0.5, but its phase differs from the Q-axis current by 180 degrees. The three-phase currents of coil X2 are the same as those of coil X1. The three-phase currents of coil Y1 are determined using the same method as those of coil X1. The three-phase currents of coil Y2 are the same as those of coil Y1.
[0062] The embodiments described above are merely preferred embodiments of this specification and are not intended to limit the scope of this specification. Any modifications and improvements made by those skilled in the art to the technical solutions of this specification without departing from the spirit of this specification should fall within the protection scope defined by the claims of this specification.
Claims
1. A planar motor comprising a mover (1) and a stator (2), the mover (1) being formed by first, second, third and fourth groups of permanent magnets (11, 12, 13, 14) arranged in a head-to-tail manner perpendicular to each other in pairs, the stator (2) comprising X windings (21) laid along the X-axis direction and Y windings (22) laid along the Y-axis direction, the X windings (21) and the Y windings (22) being three-phase distributed windings, the winding pole pitch being the same as half the width of the four groups of permanent magnets; characterized in that, The magnetization directions of the first group of permanent magnets (11) and the second group of permanent magnets (12) are the same, the magnetization directions of the third group of permanent magnets (13) and the fourth group of permanent magnets (14) are the same, and the magnetization directions of the first group of permanent magnets (11) and the third group of permanent magnets (13) are opposite.
2. The planar motor of claim 1, wherein The first group of permanent magnets (11), the second group of permanent magnets (12), the third group of permanent magnets (13) and the fourth group of permanent magnets (14) are all rectangular plate structures formed by five small permanent magnets through a Halbach array.
3. The planar motor of claim 2, wherein, In each group of permanent magnets, the magnetization directions of two adjacent small permanent magnets are perpendicular to each other, and the magnetization directions of the small permanent magnets rotate by 90° in a clockwise direction.
4. The planar motor of claim 1, wherein There is an adjustable air gap between the mover (1) and the stator (2).
5. The planar motor of claim 1, wherein, The X winding (21) is located between the Y winding (22) and the mover (1).
6. A method of operation of a planar motor, the method being applicable to a planar motor as claimed in any one of claims 1-5, characterized in that, Comprising: When the mover (1) moves linearly along the X axis, the same amplitude sinusoidal three-phase current is respectively input into the winding coil Y1 aligned with the second group of permanent magnets (12) of the stator (2) and the winding coil Y2 aligned with the fourth group of permanent magnets (14) of the stator (2), and the same phase current of the winding coil Y1 and the winding coil Y2 is 180° out of phase, so that the mover (1) runs smoothly; When the mover (1) moves linearly along the Y axis, the same amplitude sinusoidal three-phase current is respectively input into the winding coil X1 aligned with the first group of permanent magnets (11) of the stator (2) and the winding coil X2 aligned with the third group of permanent magnets (13) of the stator (2), and the same phase current of the winding coil X1 and the winding coil X2 is 180° out of phase, so that the mover (1) runs smoothly.
7. A method of operation of a planar motor, the method being applicable to a planar motor as claimed in any one of claims 1-5, characterized in that, Comprising: When the mover (1) rotates along the Z axis, the sinusoidal three-phase current is respectively input into the winding coil X1 aligned with the first group of permanent magnets (11) of the stator (2) and the winding coil X2 aligned with the third group of permanent magnets (13) of the stator (2), and the same phase current of the winding coil X1 and the winding coil X2 is 180° out of phase; the sinusoidal three-phase current is respectively input into the winding coil Y1 aligned with the second group of permanent magnets (12) of the stator (2) and the winding coil Y2 aligned with the fourth group of permanent magnets (14) of the stator (2), and the same phase current of the winding coil Y1 and the winding coil Y2 is 180° out of phase.