阅读说明：本技术 无铁芯圆筒型永磁同步直线电机 (Coreless cylindrical permanent magnet synchronous linear motor ) 是由 张君安 施志平 李博 刘波 于 2020-07-21 设计创作，主要内容包括：本发明涉及一种无铁芯圆筒型永磁同步直线电机,该电机由定子、动子组成,定子中芯棒上间隔套设有轴向充磁磁环和径向充磁磁环,磁环由钕铁硼永磁材料制作,相邻磁环单元的充磁角度依次改变90度,且磁环单元结构带有一定弧度；动子中电枢绕组是双层结构,其由三相饼状无铁芯双层线圈组成。本发明中磁环的形状为鼓状,所产生的气隙磁场可以得到均化作用,进而抑制气隙磁场高次谐波的含量和幅值,能够有效提高无铁芯圆筒型永磁同步直线电机气隙磁场的幅值与正弦型,对电机的定位精度有显著改善；其次采用双层绕组,可以提高绕组系数,能够有效克服现有无铁芯圆筒型永磁同步直线电机推力小的缺点,提高了电机的平均推力密度。(The invention relates to a coreless cylindrical permanent magnet synchronous linear motor, which consists of a stator and a rotor, wherein an axial magnetizing magnetic ring and a radial magnetizing magnetic ring are sleeved on a core rod in the stator at intervals, the magnetic rings are made of neodymium iron boron permanent magnet materials, the magnetizing angles of adjacent magnetic ring units are changed by 90 degrees in sequence, and the structure of each magnetic ring unit has a certain radian; the armature winding in the rotor is of a double-layer structure and consists of three-phase pie-shaped coreless double-layer coils. The magnetic ring is drum-shaped, the generated air gap magnetic field can be homogenized, the content and amplitude of higher harmonics of the air gap magnetic field can be further inhibited, the amplitude and sine of the air gap magnetic field of the coreless cylindrical permanent magnet synchronous linear motor can be effectively improved, and the positioning precision of the motor is remarkably improved; and secondly, the double-layer winding is adopted, so that the winding coefficient can be improved, the defect of small thrust of the existing coreless cylindrical permanent magnet synchronous linear motor can be effectively overcome, and the average thrust density of the motor is improved.)

1. Synchronous linear electric motor of no iron core drum type permanent magnetism, including stator and active cell, the stator with the active cell coaxial setting, including plug (1), its characterized in that on the stator: the magnetic core comprises a core rod (1), wherein a plurality of drum-shaped magnetic rings are sleeved on the core rod (1), the magnetic rings are divided into a radial magnetizing magnetic ring (2) and an axial magnetizing magnetic ring (3), the radial magnetizing magnetic rings and the axial magnetizing magnetic rings are arranged at intervals, and the magnetizing angles of the magnetic rings are sequentially changed by 90 degrees;

the rotor comprises an armature winding (4), the armature winding (4) is composed of three-phase cake-shaped coreless coils, the three-phase cake-shaped coreless coils are tightly arranged to form a double-layer form, the outer-layer winding and the inner-layer winding are tightly connected without leaving a gap, the outer-layer coil and the inner-layer coil are arranged to be a coaxial line, and any single-layer winding is a concentrated winding.

2. The coreless, cylindrical, permanent magnet synchronous linear motor of claim 1, wherein: the diameter of the middle of the magnetic ring is 0.5-1 mm larger than the diameters of the two ends, and the diameter of the middle is 10-12 mm.

3. The coreless cylindrical permanent magnet synchronous linear motor according to claim 1 or 2, wherein: the axial total length of the radial magnetizing magnetic ring (2) and the axial magnetizing magnetic ring (3) on the stator is larger than the axial length of the armature winding (4) on the rotor of the motor.

Technical Field

The invention belongs to the technical field of electromechanical engineering, and relates to a coreless cylindrical permanent magnet synchronous linear motor.

Background

The permanent magnet synchronous linear motor has the advantages of fast response, high acceleration, high positioning precision and the like, and is widely applied to a precision positioning system. The permanent magnet synchronous linear motor can be divided into an iron core permanent magnet synchronous linear motor and a coreless permanent magnet synchronous linear motor, the iron core permanent magnet synchronous linear motor enables the motor to generate tooth space force in the operation process due to the existence of tooth space effect, and the tooth space force can generate adverse effect on the positioning of a motion platform driven by the motor, so that the thrust fluctuation can occur. In the precise positioning, the smaller the cogging force is, the better the cogging force is, and the coreless permanent magnet synchronous linear motor can overcome the defect of the cogging force, so the coreless permanent magnet synchronous linear motor is often used as the drive of the precise positioning system. The flat permanent magnet synchronous linear motor can also generate thrust fluctuation in the positioning process due to the adverse effect of the end effect of the flat permanent magnet synchronous linear motor, the requirement of precise positioning is not facilitated, and the cylindrical permanent magnet synchronous linear motor can overcome the influence of the end effect on the operation of the motor. The coreless permanent magnet synchronous linear motor has weak air gap magnetic field intensity due to no magnetic gathering effect of a winding core, and the average thrust density of the coreless permanent magnet synchronous linear motor is smaller than that of the same coreless permanent magnet synchronous linear motor, so that inconvenience is brought to practical high-thrust application. Therefore, the defects of small thrust fluctuation and small average thrust density of the existing coreless cylindrical permanent magnet synchronous linear motor need to be overcome.

To solve the problem of thrust fluctuation, researchers at home and abroad do a lot of work from the body structure. The topological structure of the motor is optimized mainly, for example, the cogging effect of the motor is weakened by adopting methods such as a chute and an oblique pole, and the fluctuation of the thrust is reduced. However, the methods of the skewed slot and the skewed pole mainly weaken the thrust fluctuation caused by the cogging effect, and the wave form of the air gap flux density of the motor is not greatly improved. For the problem of small average thrust density, researchers at home and abroad do a lot of work from changing the structure of a coil winding, and mainly adopt distributed windings to replace centralized windings to improve winding coefficients and indirectly improve the average thrust density of a motor. Although the method can greatly improve the winding coefficient of the coil, the coil ends are mutually overlapped, and a larger space is occupied. The complex distributed winding structure does not facilitate winding of the coil and production and installation of the primary.

Disclosure of Invention

The invention aims to provide an iron-core-free cylindrical permanent magnet synchronous linear motor to solve the problems of large thrust fluctuation and small average thrust density of the conventional permanent magnet synchronous linear motor.

In order to achieve the purpose of the invention, the invention adopts the technical scheme that: the utility model provides a synchronous linear electric motor of no iron core drum type permanent magnetism, includes stator and active cell, the stator with the active cell coaxial setting, including the plug on the stator, its characterized in that: the core rod is sleeved with a plurality of drum-shaped magnetic rings, the magnetic rings are divided into a radial magnetizing magnetic ring and an axial magnetizing magnetic ring, the radial magnetizing magnetic rings and the axial magnetizing magnetic rings are arranged alternately, and the magnetizing angles of the magnetic rings are changed by 90 degrees in sequence;

the rotor comprises an armature winding, the armature winding is composed of three-phase cake-shaped coreless coils, the three-phase cake-shaped coreless coils are tightly arranged to form a double-layer form, the outer-layer winding and the inner-layer winding are tightly connected without leaving a gap, the outer-layer winding and the inner-layer winding are arranged to be a coaxial line, and any single-layer winding is a concentrated winding.

The diameter of the middle of the magnetic ring is 0.5-1 mm larger than the diameters of the two ends, and the diameter of the middle is 10-12 mm.

The axial total length of the radial magnetizing magnetic ring and the axial magnetizing magnetic ring on the stator is larger than the axial length of the armature winding on the rotor of the motor.

Compared with the prior art, the invention has the advantages that:

1. according to the coreless cylindrical permanent magnet synchronous linear motor, the axial outer surface of the magnetic ring is designed to be arc-shaped, the distribution of a magnetic field generated in an air gap space is homogenized through the design of an arc-shaped structure, air gap magnetic field harmonics are effectively inhibited, the distribution of the air gap magnetic field tends to be more sinusoidal, the influence of thrust fluctuation on the coreless cylindrical permanent magnet synchronous linear motor can be effectively reduced, and the positioning accuracy of the coreless cylindrical permanent magnet synchronous linear motor is improved.

2. The armature winding of the coreless cylindrical permanent magnet synchronous linear motor adopts the double-layer three-phase cake-shaped coreless coil, and the winding coefficient is improved by designing the three-phase cake-shaped coreless double-layer coil, so that the thrust of the motor can be increased, and the defect of small thrust of the coreless cylindrical permanent magnet synchronous linear motor can be overcome.

3. The coreless cylindrical permanent magnet synchronous linear motor adopts a Halbach magnetic pole array, wherein the axial magnetizing magnetic ring radiates outwards and inwards along the axis along the left and right directions of the axis, and the radial magnetizing magnetic ring radiates outwards and inwards along the axis, so that higher air gap magnetic field intensity can be obtained. Meanwhile, the Halbach magnetic pole array adopted by the invention has half less permanent magnet consumption than that of the Halbach magnetic pole array arranged up and down under the same magnetic field strengthening effect, and can save the consumption of the permanent magnet.

Drawings

FIG. 1 is a schematic cross-sectional view of a coreless cylindrical permanent magnet synchronous linear motor according to the present invention;

FIG. 2 is a sectional view of the drum-shaped magnetic ring structure of the coreless cylindrical permanent magnet synchronous linear motor of the present invention;

FIG. 3 is a schematic distribution diagram of Halbach permanent magnet array magnetic induction lines of the coreless cylindrical permanent magnet synchronous linear motor of the invention;

FIG. 4 is a schematic diagram of a three-phase cake-shaped coreless double-layer coil of the coreless cylindrical permanent magnet synchronous linear motor of the present invention;

the reference numerals are explained below:

1-core rod, 2-radial magnetizing magnetic ring, 3-axial magnetizing magnetic ring, 4-armature winding, 201-radial magnetizing along the axis, 202-radial magnetizing along the axis, 301-axial leftward magnetizing, 302-axial rightward magnetizing, 401-armature winding A +, 402-armature winding A-, 403-armature winding B +, 404-armature winding B-, 405-armature winding C +, 406-armature winding C-.

Detailed Description

The invention is described in detail below with reference to the figures and the specific embodiments.

As shown in fig. 1, the coreless cylindrical permanent magnet synchronous linear motor of the present invention includes a stator and a rotor, the stator and the rotor are coaxially disposed, the stator includes a core rod 1, the core rod 1 is sleeved with a plurality of drum-shaped magnetic rings, the magnetic rings are divided into a radial magnetizing magnetic ring 2 and an axial magnetizing magnetic ring 3, a magnetizing direction of the radial magnetizing magnetic ring 2 includes outward radiation along an axis and inward radiation along the axis, a magnetizing direction of the axial magnetizing magnetic ring 3 includes leftward and rightward along the axis, the two magnetic rings are arranged at intervals, and a magnetizing angle of the magnetic rings is sequentially changed by 90 degrees. The rotor comprises an armature winding 4, the armature winding 4 is composed of three-phase cake-shaped coreless coils, the three-phase cake-shaped coreless coils are tightly arranged to form a double-layer form, the outer-layer winding and the inner-layer winding are tightly connected without a gap, the outer-layer winding and the inner-layer winding are arranged to be a coaxial line, and any single-layer winding is a concentrated winding. The diameter of the middle of the magnetic ring is 0.5-1 mm larger than the diameters of the two ends, and the diameter of the middle is 10-12 mm. The axial total length of the radial magnetizing magnetic ring 2 and the axial magnetizing magnetic ring 3 on the stator is larger than the axial length of the armature winding 4 on the motor rotor, and the armature winding 4 on the motor rotor reciprocates along the length direction of the axis.

As shown in fig. 2, the radial magnetizing magnetic ring 2 and the axial magnetizing magnetic ring 3 are both made of neodymium iron boron permanent magnet materials, the magnetizing of the magnetic rings are sequentially performed by radially magnetizing the magnetic rings 201 outward along the axis, magnetizing the magnetic rings 301 leftward along the axis, radially magnetizing the magnetic rings 202 inward along the axis, and magnetizing the magnetic rings 302 rightward along the axis, and it can be found from the radial cross section that the magnetizing angles of the adjacent permanent magnet units in the present invention are changed by 90 degrees, so that "radially magnetizing the magnetic rings 201 outward along the axis", "magnetizing the magnetic rings 301 leftward along the axis", "radially magnetizing the magnetic rings 202 inward along the axis", and "magnetizing the magnetic rings 302 rightward along the axis" are taken as a magnetizing period.

As shown in fig. 3, the Halbach magnetic pole array enhances the air gap field principle, the arrangement of the permanent magnet arrays not only can increase the magnetic field between air gaps, but also can reduce the magnetic leakage at the position of the core rod, can improve the utilization rate of the magnetic ring, and the Halbach magnetic pole array of the magnetic ring structure has half less permanent magnet usage than the upper and lower arrangement under the same magnetic field strengthening effect, and can save the permanent magnet usage.

As shown in fig. 4, the three-phase pancake coreless double-layer coil is composed of an armature winding a +401, an armature winding a-402, an armature winding B +403, an armature winding B-404, an armature winding C +405 and an armature winding C-406, the three-phase windings are sequentially and tightly arranged to form an inner double-layer winding and an outer double-layer winding, and the single-layer winding adopts a concentrated arrangement form, so that the winding coefficient is improved, and the defect of small thrust of a coreless cylindrical permanent magnet synchronous linear motor can be overcome. The three-phase cake-shaped coreless double-layer coil is connected with the guide rail through the framework, an excitation magnetic field generated by the permanent magnet and three-phase current interact to generate electromagnetic thrust, and then the electromagnetic thrust can reciprocate along the guide rail under the action of a power supply and a control system. Meanwhile, the armature reaction magnetic field generated by the three-phase cake-shaped coreless double-layer coil is weaker, and the armature reaction magnetic field generated by the magnetic ring is hardly influenced, so that the air gap magnetic field can be regarded as constant, namely the excitation magnetic field generated by the magnetic ring, in the running, pause and closing periods of the coreless cylindrical permanent magnet synchronous linear motor.

The above description of the embodiments is for better understanding of the present invention, and those skilled in the art can easily make minor modifications to the magnetic ring in the above embodiments and apply the principles already described in the above embodiments to other embodiments. Therefore, the present invention is not limited to the magnetic ring structure proposed in the above embodiments, and minor modifications to the magnetic ring proposed in the present invention should be within the protection scope of the present invention.