阅读说明：本技术 一种同轴多层直驱电机及其传动控制系统 (Coaxial multilayer direct-drive motor and transmission control system thereof ) 是由 禹新路 闫亚磊 陈宗琪 李泽源 马昭仪 马佳云 于 2021-08-16 设计创作，主要内容包括：一种同轴多层直驱电机及其传动控制系统,包括安装底座、同轴叠装在所述安装底座上的若干个电机层、固定在所述若干个电机层上方的上压盖以及连接各电机层的伺服驱动器,所述每一电机层包括以电机轴心为中心设置的环形的滚珠轴承支撑座、连接在所述滚珠轴承支撑座的外环侧壁上的转子以及位于所述转子的外环侧的若干段呈环形阵列分布的定子,相邻电机层的所述滚珠轴承支撑座之间具有绕电机轴心的相对转动自由度以使相邻电机层的所述转子之间实现绕电机轴心的周向相对位移,相邻电机层的所述定子相互固定连接且所述定子与所述安装底座之间为固定连接。利用本发明可实现低高度、大直径的同轴直驱电机传动,提高电机的机械传动可靠性和信号稳定性。(The utility model provides a coaxial multilayer directly drives motor and transmission control system thereof, is including installation base, coaxial stack dress a plurality of motor layer on the installation base, fix last gland of a plurality of motor layer top and the servo driver of connecting each motor layer, each motor layer includes the annular ball bearing supporting seat that sets up as the center with the motor axle center, connects rotor on the outer loop lateral wall of ball bearing supporting seat and being located a plurality of sections of the outer loop side of rotor are the stator that annular array distributes, adjacent motor layer have between the ball bearing supporting seat around the relative rotation degree of freedom in motor axle center so that adjacent motor layer realize around the circumference relative displacement in motor axle center between the rotor, adjacent motor layer the stator mutual fixed connection just the stator with be fixed connection between the installation base. The invention can realize the transmission of the coaxial direct drive motor with low height and large diameter, and improve the mechanical transmission reliability and signal stability of the motor.)

1. The utility model provides a coaxial multilayer directly drives motor, its characterized in that, including installation base, coaxial stack dress a plurality of motor layer on the installation base, fix last gland of a plurality of motor layer top and the servo driver of connecting each motor layer, each motor layer includes the annular ball bearing supporting seat that sets up as the center with the motor axle center, connects rotor and the position on the outer loop lateral wall of ball bearing supporting seat a plurality of sections of the outer loop side of rotor are the stator that annular array distributes, adjacent motor layer have between the ball bearing supporting seat around the relative rotation degree of freedom in motor axle center so that adjacent motor layer realize around the relative displacement of circumference in motor axle center between the rotor, adjacent motor layer stator mutual fixed connection just the stator with be fixed connection between the installation base.

2. The coaxial multilayer direct-drive motor according to claim 1, wherein a motor layer close to the mounting base is a first motor layer among the plurality of motor layers, a bottom ball bearing support seat is arranged between the ball bearing support seat of the first motor layer and the mounting base, and the mounting base is fixedly connected with the bottom ball bearing support seat; the motor layer close to the upper gland seat is a top layer motor layer, a top ball bearing supporting seat is arranged between the ball bearing supporting seat of the top layer motor layer and the upper gland seat, and the upper gland seat is fixedly connected with the top ball bearing supporting seat.

3. The coaxial multilayer direct drive motor according to claim 1, wherein an elastic pre-pressing structure is arranged on the upper gland.

4. The coaxial multilayer direct drive motor according to claim 2, wherein the plurality of motor layers sequentially comprises a first motor layer, a second motor layer, a third motor layer and a top motor layer.

5. The coaxial multilayer direct drive motor according to claim 1, wherein the ball bearing support seat comprises a ball retainer and a plurality of balls, the plurality of balls are accommodated between the ball retainers of two adjacent motor layers, and a relative rotational freedom degree around a motor shaft center is provided between the two adjacent ball retainers.

6. The coaxial multilayer direct drive motor according to claim 1, wherein the three-phase windings of the stator of each motor layer are respectively connected with corresponding interfaces on the servo driver to form a plurality of independent closed-loop control systems.

7. The coaxial multilayer direct-drive motor according to claim 1, wherein the plurality of segment stators comprise a first stator segment, a second stator segment and a third stator segment, the installation angle of the first stator segment is taken as a reference 0 °, the installation angle between the second stator segment and the first stator segment is (n +1/3) times of the magnetic field period of the rotor of the motor layer, the installation angle between the third stator segment and the first stator segment is (n-1/3) times of the magnetic field period of the rotor of the motor layer, and n is a positive integer.

8. The coaxial multilayer direct drive motor according to claim 1, wherein the rotor is of a neodymium iron boron permanent magnet structure with north and south poles arranged in a staggered manner.

9. The coaxial multilayer direct drive motor according to claim 1, wherein for the rotor of each motor layer, the magnetic field period of the motor layer of the odd number layer is set to be twice the magnetic field period of the motor layer of the even number layer.

10. The coaxial multilayer direct-drive motor according to any one of claims 1 to 9, further comprising an encoder and an origin data processor which are arranged corresponding to each motor layer, wherein the encoder and the origin data processor are connected with the servo driver, and a magnetic resistance sensing chip for sensing a rotor magnetic field to obtain motor rotation angle information and a magnetic induction switch chip for sensing a rotor origin signal are integrated on the encoder and the origin data processor.

11. The coaxial multilayer direct-drive motor according to claim 10, wherein silicon steel magnetic shielding rings for shielding magnetic field interference of adjacent rotors are respectively arranged between the rotors of the two adjacent motor layers, and the silicon steel magnetic shielding rings are provided with magnetic leakage holes for using induced magnetic leakage of the magnetic induction switch chip as an origin signal.

12. A transmission control system applied to the coaxial multilayer direct drive motor as defined in any one of claims 1 to 11, comprising:

the information acquisition module comprises a magnetic resistance induction chip for acquiring the rotor magnetic field of each motor layer and a magnetic induction switch chip for acquiring the original point signal of each motor layer;

the signal processing module comprises an encoder and an origin data processor, and is used for processing the rotor magnetic field and the origin signal acquired by the information acquisition module to obtain the rotation angle information of the rotors in each layer;

and the driving module is connected with the signal processing module through an encoder protocol bus, and controls driving according to the origin signal and the rotation angle information fed back by the signal processing module.

Technical Field

The invention belongs to the technical field of direct drive motor industry, and particularly relates to a coaxial multilayer direct drive motor and a transmission control system thereof.

Background

The existing multi-layer coaxial large-diameter transmission mostly adopts a common servo motor to drive a large disc or a large ring through mechanical transmission modes such as a synchronous belt or a gear. The large-diameter direct-drive motor is mainly characterized in that a central rotating bearing is adopted to connect a stator and a rotor, and a circular grating or an angle encoder is used for feeding back the position; or the annular guide rail is used for realizing annular motion by adopting a linear motor mode. In order to ensure concentricity, a rotating shaft and a bearing are needed in the middle of the large disc or the large ring. On the other hand, the position and angle information of the multi-layer coaxial large-diameter transmission is obtained indirectly by multiplying the encoder information of the servo motor by the transmission ratio of the mechanical transmission, the driving and controlling mode of the multi-layer coaxial large-diameter transmission adopts a separated servo driver, a power cable and an encoder cable are required to be connected between each motor driver and the controller, and a mechanical or electromagnetic origin switch is required to be additionally arranged on each layer.

The disadvantages of the prior art motor drive systems include:

firstly, mechanical transmission through a synchronous belt or a gear and the like is needed, so that the precision is low, the rigidity is poor, the noise is high, and various problems such as abrasion, fatigue, cracking, looseness and the like are easy to occur;

secondly, the circular grating or the encoder needs to be coaxially installed, the internal space of the motor is occupied, and the simultaneous consideration of large hollow and small height cannot be realized; a rotating shaft and a bearing are arranged in the middle of the disc, so that a completely hollow structure cannot be realized, and the middle rotating shaft is easy to fatigue, so that the working life is short;

a power cable and an encoder cable must be connected between each motor driver and the controller, so that the anti-electromagnetic interference performance is poor, and the reliability under the vibration condition is poor; a mechanical origin switch or an electromagnetic origin switch is also required to be additionally arranged, an electrical connecting line is added, and the reliability is low under the vibration condition;

and fourthly, the position and angle information is indirectly obtained by multiplying the encoder information of the servo motor by the transmission ratio of mechanical transmission, and the precision is low, such as: the traditional general method is that a servo motor drives a large disc to rotate through a synchronous belt, the outer ring of the large disc is processed into a synchronous wheel structure, a small synchronous wheel is assembled at the end of the motor shaft, and the number n of teeth of the large disc synchronous wheel is assumed₁Number of teeth n of small synchronous gear at shaft end of motor₂The rotation angle of the large disc is theta₁The motor rotation angle is theta₂Then there is theta₁＝θ₂*n₂/n₁It is known that the synchronous belt has certain elasticity, can deform along with the increase of the service time and the change of the temperature, and the synchronous wheel and the synchronous belt have meshing errors, so that n₂/n₁If the gear is used for transmission, the abrasion of the gear and the transmission clearance also cause n₂/n₁The value is unstable, thereby causing theta₁Is unstable; after the indirectly obtained position information enters a feedback system, phenomena such as jitter and overshoot of a servo system are easily caused due to the existence of precision errors and jitter.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a coaxial multilayer direct-drive motor and a transmission control system thereof, so as to realize the coaxial direct-drive transmission with low height and large diameter and improve the mechanical transmission reliability and signal stability.

The invention firstly provides a coaxial multilayer direct-drive motor which comprises an installation base, a plurality of motor layers coaxially stacked on the installation base, an upper gland fixed above the motor layers and a servo driver connected with the motor layers, wherein each motor layer comprises an annular ball bearing supporting seat arranged by taking a motor axis as a center, a rotor connected on the outer ring side wall of the ball bearing supporting seat and a plurality of sections of stators distributed in an annular array manner and positioned on the outer ring side of the rotor, relative rotation freedom degrees around the motor axis are arranged between the ball bearing supporting seats of adjacent motor layers so as to realize circumferential relative displacement around the motor axis between the rotors of the adjacent motor layers, the stators of the adjacent motor layers are fixedly connected with each other, and the stators are fixedly connected with the installation base.

Furthermore, in the plurality of motor layers, a motor layer close to the mounting base is taken as a first motor layer, a bottom ball bearing supporting seat is arranged between the ball bearing supporting seat of the first motor layer and the mounting base, and the mounting base is fixedly connected with the bottom ball bearing supporting seat; the motor layer close to the upper gland seat is a top layer motor layer, a top ball bearing supporting seat is arranged between the ball bearing supporting seat of the top layer motor layer and the upper gland seat, and the upper gland seat is fixedly connected with the top ball bearing supporting seat.

Furthermore, an elastic pre-pressing structure is arranged on the upper gland.

Further, the plurality of motor layers sequentially comprise a first motor layer, a second motor layer, a third motor layer and a top motor layer.

Furthermore, the ball bearing support seat comprises a ball retainer and a plurality of balls, the balls are accommodated between the ball retainers of the two adjacent motor layers, and a relative rotational freedom degree around the motor axis is formed between the two adjacent ball retainers.

Furthermore, the three-phase windings of the stators of the motor layers are respectively connected with corresponding interfaces on the servo driver to form a plurality of independent closed-loop control systems.

Further, the plurality of stator sections comprise a first stator section, a second stator section and a third stator section, the installation angle of the first stator section is taken as a reference 0 degree, the installation angle between the second stator section and the first stator section is (n +1/3) times of the magnetic field period of the rotor of the motor layer where the stator is located, the installation angle between the third stator section and the first stator section is (n-1/3) times of the magnetic field period of the rotor of the motor layer where the stator is located, and n is a positive integer.

Furthermore, the rotor adopts a neodymium iron boron permanent magnet structure with staggered north and south poles.

Further, for the rotors of the motor layers, the magnetic field period of the motor layer of the odd number layer is set to be twice the magnetic field period of the motor layer of the even number layer.

Furthermore, the coaxial multilayer direct-drive motor further comprises an encoder and an origin data processor which are arranged corresponding to the motor layers, the encoder and the origin data processor are connected with the servo driver, and a magnetic resistance sensing chip for sensing a rotor magnetic field to obtain motor rotation angle information and a magnetic induction switch chip for sensing a rotor origin signal are integrated on the encoder and the origin data processor.

And further, a silicon steel magnetic shielding ring used for shielding magnetic field interference of adjacent rotors is arranged between the rotors of the two adjacent motor layers, and a magnetic leakage hole used for inducing magnetic leakage of the magnetic induction switch chip as an original point signal is formed in the silicon steel magnetic shielding ring.

The invention also provides a transmission control system of the coaxial multilayer direct drive motor, which comprises:

the information acquisition module comprises a magnetic resistance induction chip for acquiring the rotor magnetic field of each motor layer and a magnetic induction switch chip for acquiring the original point signal of each motor layer;

the signal processing module comprises an encoder and an origin data processor, and is used for processing the rotor magnetic field and the origin signal acquired by the information acquisition module to obtain the rotation angle information of the rotors in each layer;

and the driving module is connected with the signal processing module through an encoder protocol bus, and controls driving according to the origin signal and the rotation angle information fed back by the signal processing module.

According to the coaxial multilayer direct-drive motor and the transmission control system thereof, the rotary support and the rotor serving as a motor power source are integrated, and the multilayer large-diameter coaxial direct-drive motor which is low in height, large in hollow and directly driven is realized together with the stator; because the intermediate rotating shaft is eliminated, intermediate transmission links such as a synchronous belt, a gear and the like are not needed, the mechanical rigidity and the mechanical transmission precision can be improved, the mechanical transmission reliability is improved, and the mechanical noise is reduced; the angle information and the motor power collected by the encoder are both from the same magnetic field, and other additional sensors are not needed, so that direct position information collection is realized, the signal stability is improved, the stability of a servo feedback system is improved, fewer mounting components are required, direct drive transmission with low height and large diameter is realized, intermediate connecting cables are reduced to the maximum extent, and the reliability and the anti-electromagnetic interference capability of the system are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is one of the schematic structural diagrams of the coaxial multilayer direct drive motor of the present invention;

FIG. 2 is a second schematic structural view of the coaxial multi-layer direct drive motor of the present invention;

FIG. 3 is a third schematic structural view of the coaxial multi-layer direct drive motor of the present invention;

FIG. 4 is a schematic view of a partial structure of a rotor of the coaxial multilayer direct drive motor of the present invention;

FIG. 5 is a schematic diagram of the encoder and origin data processor of the coaxial multi-layer direct drive motor of the present invention;

FIG. 6 is a schematic view of a partial structure of a ball bearing support base of the coaxial multi-layer direct drive motor of the present invention;

fig. 7 is a configuration diagram of a transmission control system of the coaxial multilayer direct drive motor of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without any inventive step, are within the scope of the present invention.

Furthermore, the following description of the various embodiments refers to the accompanying drawings, which illustrate specific embodiments in which the invention may be practiced. Directional phrases used in this disclosure, such as, for example, "upper," "lower," "front," "rear," "left," "right," "inner," "outer," "side," and the like, refer only to the orientation of the appended drawings and are, therefore, used herein for better and clearer illustration and understanding of the invention, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the invention.

Referring to fig. 1 to 3, a coaxial multi-layer direct-drive motor includes a mounting base 100, a plurality of motor layers 200 coaxially stacked on the mounting base 100, an upper gland 300 fixed above the plurality of motor layers 200, and a servo driver 400 connected to each motor layer 200, where each motor layer 200 includes an annular ball bearing support base 210 disposed with a motor axis as a center, a rotor 220 connected to an outer ring sidewall of the ball bearing support base 210, and a plurality of segments of stators 230 located at an outer ring side of the rotor 220 and distributed in an annular array, a relative rotational freedom degree around the motor axis is provided between the ball bearing support bases 210 of adjacent motor layers to enable the rotors 220 of adjacent motor layers to realize a circumferential relative displacement around the motor axis, the stators 230 of adjacent motor layers are fixedly connected to each other, and the stators 230 and the mounting base 100 are fixedly connected to each other.

The coaxial multilayer direct drive motor of the embodiment integrates the rotary support with the rotor 220 serving as a motor power source, and realizes a multilayer large-diameter coaxial direct drive motor which is low in height, large in hollow and directly driven together with the stator 230; a common fault point is eliminated due to the elimination of the middle rotating shaft; intermediate transmission links such as synchronous belts and gears are not needed, so that the mechanical rigidity and the mechanical transmission precision can be improved, the mechanical transmission reliability is improved, and the mechanical noise is reduced.

In this embodiment, the number of layers of the motor layer is four, and the plurality of motor layers sequentially include a first motor layer 201, a second motor layer 202, a third motor layer 203, and a top motor layer 204. A motor layer close to the mounting base 100 is taken as a first motor layer 201, a bottom ball bearing support seat 211 is arranged between a ball bearing support seat of the first motor layer 201 and the mounting base 100, and the mounting base 100 is fixedly connected with the bottom ball bearing support seat 211; the motor layer close to the upper gland seat 300 is used as the top motor layer 204, a top ball bearing support seat 216 is arranged between the ball bearing support seat of the top motor layer 204 and the upper gland seat 300, and the upper gland seat 300 is fixedly connected with the top ball bearing support seat 216. The first motor layer 201 includes a first ball bearing support base 212, a first rotor 221 and a first stator 231, the second motor layer 202 includes a second ball bearing support base 213, a second rotor 222 and a second stator 232, the third motor layer 203 includes a third ball bearing support base 214, a third rotor 223 and a third stator 233, and the top motor layer 204 includes a fourth ball bearing support base 215, a fourth rotor 224 and a fourth stator 234. A bottom ball bearing support 211 as a first layer of a multi-layered ball bearing support is mounted on the mounting base 100, a first ball bearing support 212 as a second layer of the multi-layered ball bearing support is mounted on the bottom ball bearing support 211, a second ball bearing support 213 as a third layer of the multi-layered ball bearing support is mounted on the first ball bearing support 212, a third ball bearing support 214 as a fourth layer of the multi-layered ball bearing support is mounted on the second ball bearing support 213, a fourth ball bearing support 215 as a fifth layer of the multi-layered ball bearing support is mounted on the third ball bearing support 214, and a top ball bearing support 216 as a sixth layer of the multi-layered ball bearing support is mounted on the fourth ball bearing support 215; the ball bearing supports 210 can rotate freely around the axis of the motor. The bottom ball bearing support seat 211 is fixedly connected with the mounting base 100 to restrain the axial freedom of each layer of rotor.

Referring to fig. 3, the ball bearing support 210 includes a ball retainer 217 and a plurality of balls 218. The ball retainers 217 are provided with grooves for accommodating the balls 218, a plurality of balls 218 are accommodated between the ball retainers 217 of two adjacent motor layers, and the two adjacent ball retainers 217 have relative rotational freedom around the motor axes. The adjacent two motor layers realize relative rotation through the cooperation of the ball retainer 217 and the balls 218.

In the present embodiment, the rotor 220 is made of a neodymium-iron-boron permanent magnet structure with alternating north and south poles. The neodymium iron boron permanent magnets with staggered north and south poles are respectively arranged on the outer ring side walls of the first ball bearing supporting seat 212, the second ball bearing supporting seat 213, the third ball bearing supporting seat 214 and the fourth ball bearing supporting seat 215 to form a direct-drive motor rotor, the rotary support and the motor power source are integrated, and the large-diameter coaxial direct-drive motor with low height, large hollow and direct drive is realized together with the multilayer direct-drive motor stator.

In the present embodiment, the stator 230 is composed of a coil, and its internal structure is identical to that of a general servo motor or a permanent magnet synchronous linear motor. The first stator 231, the second stator 232, the third stator 233 and the fourth stator 234 are sequentially fixedly connected and mounted on the mounting base 100. The first rotor 221 and the first stator 231 form a first layer large-diameter direct drive motor, the second rotor 222 and the second stator 232 form a second layer large-diameter direct drive motor, the third rotor 223 and the third stator 233 form a third layer large-diameter direct drive motor, and the fourth rotor 224 and the fourth stator 234 form a fourth layer large-diameter direct drive motor.

In the preferred embodiment of the present invention, the upper gland 300 is provided with an elastic pre-pressing structure to adjust the pre-pressing force of the upper gland 300, so as to improve the assembly stability. The elastic pre-pressing structure can adopt a spring mode and the like.

Referring to fig. 2, each stator layer in the present invention may be composed of three or more stator segments. In the present embodimentThe plurality of stator segments comprises a first stator segment 235, a second stator segment 236 and a third stator segment 237, the three stator segments being distributed over the circumference of the outside of the rotor. In order to reduce the torque ripple of the direct drive motor, the installation angle between the three stator segments is set to be (n + -1/3) times of the motor rotor magnetic field period tau, wherein n is a positive integer. Taking the installation angle of the first stator segment 235 as a reference 0 °, the installation angle between the second stator segment 236 and the first stator segment 235 is (n +1/3) times of the magnetic field period of the rotor of the motor layer, and the installation angle between the third stator segment 237 and the first stator segment 235 is (n-1/3) times of the magnetic field period of the rotor of the motor layer. In general, thrust fluctuations are periodic forces related to the period of the magnetic field, i.e. thrust fluctuations T_rippleWhere a is the motor rotational speed, v is the initial phase of the motor rotor relative to the stator and can be made zero by control techniques, the total thrust ripple T produced by the three stator segments is_ripple＝A*cos(τ/v+φ)+A*cos(τ/v+φ+φ₁)+A*cos(τ/v+φ+φ₂)，φ₁And phi₂The relative angles of the second stator segment, the third stator segment and the first stator segment can be controlled to be 0 when phi is respectively₁And phi₂When the magnetic field period is 1/3 times and-1/3 times respectively, the three-part stator is symmetrically installed and T_rippleIs smaller. In one embodiment of the present invention, the mounting angle between the second stator segment 236 and the first stator segment 235 is 118.57 °, and the mounting angle between the third stator segment 237 and the first stator segment 235 is 118.67 °.

Referring to fig. 4, for the rotor 220 of each motor layer, the magnetic field period of the motor layer of the odd number layer is set to be twice the magnetic field period of the motor layer of the even number layer to reduce motor torque ripple caused by mutual interference of the magnetic fields of the upper and lower layers (N/S in the figure represents south/north poles of the magnets, respectively). In this embodiment, the first motor layer 201 and the third motor layer 203 are odd-numbered motor layers, the second motor layer 202 and the top motor layer 204 are even-numbered motor layers, and the magnetic field period of the first motor layer 201 and the third motor layer 203 is set to be twice the magnetic field period of the second motor layer 202 and the top motor layer 204. In general, if τ₁＝τ₂To aboveWhen the lower two layers rotate relatively, the thrust fluctuation formed by the simultaneous attraction or repulsion of the south pole or the north pole of the magnet is the largest, which can be expressed as F_rippleA, (tau/v) a, (tau/v + pi) 2 a, (tau/v) v is the relative rotation speed of the motor; and if tau₁＝2*τ₂Then F is_ripple＝A*cos(τ₂/v)-A*cos(τ₂/v+π/2)＝√2*A*cos(τ₂V-pi/4) to reduce the amplitude of thrust fluctuations.

Referring to fig. 5, the coaxial multilayer direct drive motor according to the embodiment of the present invention further includes an encoder and an origin data processor 500 disposed corresponding to each motor layer, the encoder and the origin data processor 500 are connected to the servo driver 400, and the encoder and the origin data processor are integrated with a magnetic resistance sensing chip 501 for sensing a rotor magnetic field to obtain motor rotation angle information and a magnetic induction switch chip 502 for sensing a rotor origin signal. The magnetic resistance induction chip 501 is used for detecting the north-south alternating magnetic field of each layer of the rotor and processing data to obtain the rotation angle of each layer of the rotor and output the rotation angle to the servo driver 400 in a coding manner, and meanwhile U, V, W three-phase windings of the four stator coils of the first stator 231, the second stator 232, the third stator 233 and the fourth stator 234 are respectively connected with corresponding interfaces on the servo driver 400 to form four independent closed-loop control systems. The encoder adopts a four-axis integrated encoder, the rotation angle information processed by the encoder and the motor power use the same magnetic field, and other additional sensors are not needed, so that direct position information acquisition is realized, an intermediate link is omitted, the precision is improved, and fewer mounting parts are used, and direct drive transmission with low height and large diameter is easily realized; the servo driver adopts a multi-axis integrated servo driver, power lines of all motor layers are connected with all corresponding interfaces on the multi-axis integrated servo driver, the rotation angle information and the original point signal are connected into the multi-axis integrated servo driver through a multi-axis integrated encoder and a protocol bus of an original point data acquisition processor, a feedback system is formed by utilizing the rotation angle information acquired directly, the signal stability can be improved, and the stability of the servo feedback system is improved; the integrated encoder, the original point data acquisition processor and the integrated servo driver can reduce intermediate connecting cables to the maximum extent and improve the reliability and the anti-electromagnetic interference capability.

Referring to fig. 6, silicon steel magnetic shielding rings 240 for shielding magnetic field interference of adjacent rotors are respectively disposed between the rotors 220 of two adjacent motor layers, and the silicon steel magnetic shielding rings 240 are provided with magnetic leakage holes 241 for using magnetic induction leakage induced by the magnetic induction switch chips 502 as original signals. In one embodiment of the present invention, the silicon steel magnetic shielding ring 240 is disposed on the ring surface where the two motor layers are connected. In another embodiment of the present invention, silicon steel magnetic shielding rings 240 are respectively disposed along the axial direction of adjacent motor layers in the axial direction thereof, so as to shield interference between the rotor magnetic fields of the upper and lower layers. Each magnetic shield ring 240 has a magnetic leakage hole 241, and a magnetic induction switch chip 502 integrated on the encoder and the origin data acquisition processor 500 is used to induce magnetic leakage in the magnetic leakage hole 241 as an origin signal.

Referring to fig. 7, an embodiment of the present invention further provides a transmission control system for a coaxial multilayer direct drive motor, including:

the information acquisition module comprises a magnetic resistance induction chip for acquiring a rotor magnetic field of each motor layer and a magnetic induction switch chip for acquiring an original point signal of each motor layer;

the signal processing module comprises an encoder and an origin data processor, and is used for processing an origin signal acquired by the information acquisition module and a rotor magnetic field to obtain rotation angle information of each layer of rotor;

the driving module comprises a multi-axis integrated servo driver and other controllers or servo drivers, wherein the multi-axis integrated servo driver is connected with the signal processing module through an encoder protocol bus, and the multi-axis integrated servo driver controls the driving of the other controllers or other servo drivers according to an origin signal and rotation angle information fed back by the signal processing module.

Preferably, the magnetic resistance sensing chip and the magnetic induction switch chip of the information acquisition module are integrated on the encoder and the origin data processor of the signal processing module.

In the transmission control system of the coaxial multilayer direct-drive motor, the angle information and the motor power acquired by the encoder are both from the same magnetic field, and other additional sensors are not needed, so that direct position information acquisition is realized, and the transmission control system has few installation parts and is beneficial to realizing the direct-drive transmission with low height and large diameter; the rotation position information comes from a motor rotor magnetic field, an intermediate link is not provided, the angle information is directly rotated to form a feedback system, the precision is improved, the signal stability is improved, and the stability of a servo feedback system is improved; each layer of motor layer is respectively connected with the servo driver through each motor power line, specifically, U, V, W three-phase windings (namely motor UVW lines) of each layer of stator coil are respectively connected with corresponding interfaces on the multi-shaft integrated servo driver to form four independent closed-loop control systems; the rotation angle information and the original point signal are accessed into the multi-axis integrated servo driver through the multi-axis integrated encoder and a protocol bus of the original point data acquisition processor, so that intermediate connecting cables are reduced to the maximum extent, and the reliability and the anti-electromagnetic interference capability are improved.

The above is not limited to the embodiments of the present invention, the above description of the specific embodiments is intended to describe and illustrate the technical solutions of the present invention, and the above specific embodiments are only schematic and are not limiting. Any person skilled in the art can substitute or change the technical scheme and the inventive concept of the present invention equally within the scope of the present invention.