CN207321085U - A kind of novel permanent magnetic array and planar motor - Google Patents

Abstract

The utility model relates to the field of motors, in particular to a novel permanent magnet array and a planar motor. A hexagonal right prism permanent magnet is used to form a new topology of permanent magnet array. The expression of the magnetic induction intensity of the permanent magnet array is deduced by the magnetic scalar potential and Fourier series. Compared with the previous permanent magnet array, the structure is more compact, and there is no gap between the permanent magnets; using the superposition principle and Fourier series, the expression of the magnetic induction intensity is derived, and by introducing the effective amplitude, a new expression can be used for real-time control ; The magnetic induction intensity in the Z direction is greater, and the high-order harmonic components are smaller, so the fluctuation of the plane motor force can be reduced.

Description

A New Type of Permanent Magnet Array and Planar Motor

technical field

The utility model relates to the field of motors, in particular to a novel permanent magnet array and a planar motor.

Background technique

The magnetic levitation planar motor realizes non-contact and wear-free planar movement through magnetic levitation. Compared with the traditional planar motion structure composed of linear guide rails orthogonally combined, the maglev planar motor does not need guide rail support. It has important application prospects. For the moving iron type magnetic levitation planar motor, because the coil array is arranged on the stator, there is no electrical connection and cooling pipeline of the mover to hinder the movement, and the heat of the motor is also easier to dissipate, which is beneficial to the improvement of the system's motion performance.

Today's integrated circuit equipment market is growing rapidly, and lithography machines are the most complex core equipment in the manufacture of integrated circuit equipment. The maglev planar motor directly uses electromagnetic energy to generate planar motion. It has the characteristics of high output density, low heat consumption, and high precision. It can integrate the control object and the motor into an integrated structure. With the advantages of good performance, it will become an important driving form for high-speed and precision processing equipment.

The permanent magnet array is the main part of the electromagnetic structure of the maglev planar motor, and the magnetic field generated by it drives the motor to move. Therefore, the permanent magnetic array structure requires high efficiency and low harmonics. Cho et al proposed a compact Halbach permanent magnet array for moving-iron planar motors, which can achieve higher magnetic field strength than traditional NS arrays. The harmonic model of its magnetic induction is derived from the magnetic scalar potential, but the analytical formula is more complicated. In order to facilitate real-time control, a sine function is used to approximate the magnetic induction. Compter and Jansen et al. used different two-dimensional Halbach permanent magnet arrays, and also used the magnetic scalar potential to derive the harmonic model of the magnetic induction intensity, but did not consider the influence of higher harmonics on the entire permanent magnet array. The two-dimensional Halbach permanent magnet array proposed by Min et al. aims to minimize the high-order harmonic component, and optimizes the structural parameters of the permanent magnet array by using genetic algorithm. Y Zhang and L Huang et al. used trapezoidal permanent magnets in permanent magnet arrays, and found that trapezoidal permanent magnets can reduce the high-order harmonic components of magnetic induction. Peng Junrong proposed a two-dimensional permanent magnet array using trapezoidal permanent magnets, and obtained a permanent magnet array structure that reduces high-order harmonic components and enhances the magnetic field. However, the analytical formula of the harmonic model of the magnetic induction is too complicated. The Halbach permanent magnet array makes the magnetic field on one side of the array significantly enhanced while the other side is significantly weakened, and it is easy to obtain a more ideal sinusoidal magnetic field distribution in space, so it is often used in the design of maglev planar motors.

Utility model content

The technical problem to be solved by the utility model is that there are gaps between the existing permanent magnet array structures, the structure is not compact enough, the calculation of the magnetic induction intensity is not accurate enough, and the Z-direction magnetic induction intensity is not large enough, resulting in large fluctuations in the planar motor.

In order to solve the above problems, the utility model provides a new type of permanent magnet array and planar motor, including hexagonal straight prism permanent magnets and quadrangular prism magnets, the hexagonal straight prism permanent magnets are closely arranged on the quadrangular prism magnets The four sides constitute an octagonal right prism, and the side length and height of the hexagonal right prism permanent magnet are equal to those of the quadrangular prism magnetizer; specifically, the mth row along the x-axis direction is a hexagonal right prism permanent magnet that is in point contact and arranged closely. The magnetization direction of the adjacent hexagonal right prism permanent magnets is opposite along the y-axis, and the m+1th row is that the hexagonal right prism permanent magnets are closely arranged in line contact with the quadrangular prism magnetizer, and the two sides of the quadrangle prism magnetizer The magnetization direction of the hexagonal right prism permanent magnets is opposite along the x-axis, and the hexagonal right prism permanent magnets in the mth row and the hexagonal right prism permanent magnets in the m+1th row are closely arranged in line contact; along the y-axis direction The nth column is a hexagonal right prism permanent magnet point contact closely arranged, the magnetization direction of the adjacent hexagonal right prism permanent magnet is opposite along the x-axis, the n+1th column is a hexagonal right prism permanent magnet and four The prismatic magnetizers are closely arranged in line contact, the magnetization direction of the hexagonal right prism permanent magnets on both sides of the quadrangle prism magnetizer is opposite along the y-axis, the hexagonal right prism permanent magnets in the nth column and the n+1th column The hexagonal right prism permanent magnets are closely arranged in line contact; the direction of the magnetic field lines of adjacent four prism magnetizers is opposite. , the direction of the magnetic lines of force of the quadrangular prism magnetizer is along the z-axis, and when the magnetization directions of the hexagonal right prism permanent magnets on the four sides of the quadrangular prism magnetizer are all facing away from the quadrangular prism magnetizer, the The direction of the magnetic force line is outward along the z-axis.

Further, the hexagonal straight prism permanent magnet adopts rare earth permanent magnet.

Further, the quadrangular prism magnetizer is a ferromagnetic material.

The application of the above-mentioned novel permanent magnet array is used for the permanent magnet array of a planar motor.

A planar motor uses the above-mentioned novel permanent magnet array as a stator or a mover. The permanent magnet array of the planar motor uses hexagonal right prism permanent magnets to form a new topology of the permanent magnet array. The expression of the magnetic induction intensity of the permanent magnet array is deduced by the magnetic scalar potential and Fourier series. Compared with the previous permanent magnet array, it has the following advantages:

(1) Hexagonal right prism permanent magnets magnetized in x and y directions are used.

(2) The structure of the permanent magnet array is more compact, there is no gap between the permanent magnets, no filling material, and the magnet steel fills the entire space. Therefore, when calculating the magnetic induction intensity, it is not necessary to assume that the relative permeability of the permanent magnet is 1, and the calculation result is more accurate.

(3) Using the superposition principle and the analysis method of Fourier series, the expression of the magnetic induction intensity is deduced. By introducing the effective amplitude, a new expression can be used for real-time control.

(4) The Z-direction magnetic induction of the new permanent magnet array is larger, about 10% larger at 4mm. Through optimization analysis, the high-order harmonic components are smaller, so the fluctuation of the planar motor force can be reduced.

Description of drawings

Fig. 1 is the top view of the utility model permanent magnet array;

Fig. 2 is the sectional view of permanent magnet array of the present utility model;

Fig. 3 is the projection of the x magnetization direction of the hexagonal permanent magnet in the x direction;

Fig. 4 is the projection of the x magnetization direction of the hexagonal permanent magnet in the y direction;

Fig. 5 is a periodic function diagram;

Fig. 6 is a calculation diagram of magnetic induction;

Figure 7 is an optimization analysis diagram calculated on the basis of Bz;

Fig. 8 is optimized with Matlab genetic algorithm, the optimized figure of effective amplitude method;

Fig. 9 is a magnetic induction intensity distribution diagram a;

Fig. 10 is a magnetic induction intensity distribution diagram b;

Figure 11 is a high-order harmonic diagram;

Fig. 12 is a comparison a between the magnetic steel array of the present invention and the Jansen array;

Fig. 13 is a contrast b between the magnetic steel array of the present invention and the Jansen array;

In the figure, a hexagonal right prism permanent magnet 1 and a quadrangular prism magnetizer 2.

Detailed ways

The utility model is described in detail below in conjunction with the accompanying drawings, but the utility model is not limited to specific embodiments.

Example 1:

As shown in Figure 1, a new type of permanent magnet array includes a hexagonal right prism permanent magnet 1 and a quadrangular prism magnet 2, and the hexagonal right prism permanent magnets are closely arranged on the four sides of the quadrangular prism magnet 2 to form eight Hexagonal right prism, the side length and height of the hexagonal right prism permanent magnet 1 are equal to the square prism magnetizer 2; specifically, the mth row along the x-axis direction is a hexagonal right prism permanent magnet 1 point contact closely arranged, The magnetization direction of the adjacent hexagonal right prism permanent magnet 1 is opposite along the y-axis, and the m+1th row is that the hexagonal right prism permanent magnet 1 and the quadrangular prism-shaped magnetizer 2 are closely arranged in line contact, and the quadrangular prism-shaped magnetizer 2 The magnetization directions of the hexagonal right prism permanent magnets 1 on both sides are opposite along the x-axis, and the hexagonal right prism permanent magnet 1 in the mth row is in line contact with the hexagonal right prism permanent magnet 1 in the m+1th row Closely arranged; the nth column along the y-axis direction is a hexagonal right prism permanent magnet 1 point contact closely arranged, the magnetization direction of the adjacent hexagonal right prism permanent magnet 1 is opposite along the x-axis, and the n+1th column is The hexagonal right prism permanent magnet 1 and the quadrangular prism magnetizer 2 are closely arranged in line contact, and the magnetization direction of the hexagonal straight prism permanent magnet 1 on both sides of the quadrangular prism magnetizer 2 is opposite along the y-axis, and the nth column The hexagonal straight prism permanent magnet 1 and the hexagonal straight prism permanent magnet 1 in the n+1th column are closely arranged in line contact; the direction of the magnetic force lines of the adjacent quadrangular prism magnetizer 2 is opposite, when the four sides of the quadrangular prism magnetizer 2 have six sides When the magnetization direction of the rectangular prism permanent magnet 1 points to the quadrangular prism magnetizer 2, the direction of the magnetic field line of the quadrangular prism magnetizer 2 is along the z-axis. When the magnetization direction of the magnet 1 is all facing away from the quadrangular prism magnetizer 2, the direction of the magnetic force lines of the quadrangular prism magnetizer 2 is outward along the z-axis.

A use of the novel permanent magnet array described in claim 1, characterized in that it is used for the permanent magnet array of a planar motor.

A planar motor, characterized in that: the novel permanent magnet array described in claim 1 is used as a stator or a mover.

Example 2:

The hexagonal straight prism permanent magnet 1 adopts a rare earth permanent magnet.

The quadrangular prism magnetizer 2 is a ferromagnetic material.

All the other are identical with embodiment 1.

Traditional Halbach arrays use cuboid or cube permanent magnets. The utility model tries to add a hexagonal straight prism permanent magnet, and using this permanent magnet can make there be no gap between the magnetic steel arrays; and refer to the paper Modeling and Analysis of a New 2-D Halbach Array for Magnetically Levitated Planar Motor to calculate the magnetic steel array The space magnetic induction intensity of the application paper Analysis and Optimization of a New 2-DMagnet Array for Planar Motor optimization method to optimize this magnetic steel array, and then use the paper Modeling and Analysis of a New 2-D Halbach Array for Magnetically Levitated Planar Motor The method is to simplify the replacement of the magnetic steel array. Finally, a comparison between the magnetic steel array and the Jansen array is given:

(1) Calculation of the magnetic induction intensity of the magnetic steel array: the theory uses the magnetic scalar potential and the Fourier series analysis method, and the array is shown in Figure 1;

As shown in Figure 3, the hexagonal permanent magnet, the x magnetization direction, the projection in the x direction, the periodic function in Figure 3 is expressed as

Even function, b _n =0, calculated a ₀ =0

The a _n in the above formula replaces t with d, and recalculates, the cycle is

get

As shown in Figure 4, the hexagonal permanent magnet, the x magnetization direction, the projection in the y direction, the projection changes, so the function y=v(x) is substituted, and the periodic function in Figure 4 represents

Odd function, a _n ＝0, calculated a ₀ ＝0

It contains the function v(x), and the function is obtained according to the range of x as follows

Since it is 0 at m=2, 4, 6, 8..., the following results are obtained

The coefficient distribution of the above function is obtained, which is a periodic function, as shown in Figure 5. periodic function expression

Even function, b _n ＝0, a ₀ ＝0

Get the Fourier expression for the magnetization

in

e ₁ =k+l+u

e ₂ =k+lu

e ₃ =k-l+u

e ₄ = klu

in

e ₅ =l+k+u

e ₆ =l+ku

e ₇ =l-k+u

e ₈ = lku

in:

Establish a conditional expression for this, and calculate the magnetic induction intensity (as shown in Figure 6)

Let μ _r =1,

The expression of magnetic induction intensity is as follows:

in

e ₁ =k+l+u, e ₂ =k+lu, e ₃ =k-l+u, e ₄ =klu

e ₅ =l+k+u, e ₆ =l+ku, e ₇ =l-k+u, e ₈ =lku

(2) Optimization analysis: calculation based on Bz;

The selected area is shown in the black thick line box in Figure 7

There are formulas

Calculate, when n is the order, get Less than 6×10 ^-5 T of the earth's magnetic field.

When k=1, l=49, u=49, the amplitude at this time is -2.664e-05. So when any one of k and l is greater than 49, the harmonics can be ignored.

get at this time

B _z =1.375415547250888

get

The sum of the magnetic induction in this area.

The optimization function is as follows

Relational

Optimization with Matlab Genetic Algorithm, Optimization of Effective Amplitude Method

The following optimization results are from the pitch_optim_asa.m file, as shown in Figure 8

Optimization running.

Objective function value: 5.1052859201288986E-5

Optimization terminated: maximum number of generations exceeded.

The optimized result value obtained

0.4099541518376512≈0.41

fval=5.1052859201288986E-5

The distribution of magnetic induction intensity needs to be changed, as shown in Figure 9 and Figure 10;

The values of higher order harmonics are shown in Figure 11;

(3) Data comparison, compared with the Jansen array of the utility model, as shown in Figure 12 and Figure 13, the utility model has the following advantages compared with the previous permanent magnet array:

(1) Hexagonal right prism permanent magnets magnetized in x and y directions are used.

(2) The structure of the permanent magnet array is more compact, there is no gap between the permanent magnets, no filling material, and the magnet steel fills the entire space. Therefore, when calculating the magnetic induction intensity, it is not necessary to assume that the relative permeability of the permanent magnet is 1, and the calculation result is more accurate.

(3) Using the superposition principle and the analysis method of Fourier series, the expression of the magnetic induction intensity is deduced. By introducing the effective amplitude, a new expression can be used for real-time control.

(4) The Z-direction magnetic induction of the new permanent magnet array is larger, about 10% larger at 4mm. Through optimization analysis, the high-order harmonic components are smaller, so the fluctuation of the planar motor force can be reduced.

Claims (5)

1. A novel permanent magnet array is characterized in that: it comprises a hexagonal right prism permanent magnet and a quadrangular prism magnet, and the hexagonal straight prism permanent magnet is closely arranged on the four sides of the quadrangular prism magnet to form an octagonal straight Prism, the side length and height of the hexagonal right prism permanent magnet are equal to the quadrangle prism magnetizer; specifically, the mth row along the x-axis direction is a hexagonal right prism permanent magnet in point contact and closely arranged, and the adjacent hexagonal straight prism The magnetization direction of the prismatic permanent magnet is opposite along the y-axis. The m+1th row is a hexagonal right prism permanent magnet and a quadrangular prism magnet that are in close contact with each other. The magnetization direction of the magnet is opposite along the x-axis, the hexagonal right prism permanent magnets in the mth row and the hexagonal right prism permanent magnets in the m+1th row are closely arranged in line contact; the nth column along the y-axis direction is a hexagonal The straight prism permanent magnets are closely arranged in point contact, the magnetization direction of the adjacent hexagonal right prism permanent magnets is opposite along the x-axis, and the n+1th column is the line contact between the hexagonal right prism permanent magnet and the quadrangular prism magnetizer Closely arranged, the magnetization direction of the hexagonal right prism permanent magnets on both sides of the quadrangular prism magnetizer is opposite along the y axis, the hexagonal right prism permanent magnet in the nth column and the hexagonal right prism in the n+1th column The permanent magnets are closely arranged in line contact; the direction of the magnetic field lines of adjacent four-sided prism magnetizers is opposite. The direction of the magnetic lines of force is along the z axis. When the magnetization directions of the hexagonal right prism permanent magnets on the four sides of the quadrangular prism magnetizer are all facing away from the quadrangular prism magnetizer, the direction of the magnetic force lines of the quadrangular prism magnetizer is along the z axis. outward. 2. The novel permanent magnet array according to claim 1, characterized in that: the hexagonal straight prism permanent magnet adopts rare earth permanent magnet. 3. The novel permanent magnet array according to claim 1, characterized in that: the quadrangular prism magnetizer is ferromagnetic material. 4. The application of the novel permanent magnet array as claimed in claim 1, characterized in that: it is used for the permanent magnet array of a planar motor. 5. A planar motor, characterized in that: the novel permanent magnet array according to claim 1 is used as a stator or a mover.