Concave salient pole permanent magnet synchronous linear motor and rotary motor

Abstract

The application relates to a reverse salient permanent magnet synchronous linear motor and a rotary motor and relates to the technical field of motors. The application aims to solve the problems that the amount of permanent magnets and the flexibility of arrangement are low due to structural limitations of the current surface-mounted permanent magnet synchronous linear motor, and the speed operation range is small because the reluctance thrust cannot be utilized. The reverse salient permanent magnet synchronous linear motor is characterized in that a plurality of permanent magnets are uniformly arranged along the movement direction of the secondary core and are embedded in the secondary core, the magnetization direction of the permanent magnets is the same as the movement direction of the secondary core, N layers of magnetic separation grooves are formed on the two sides of each permanent magnet, the magnetic separation grooves on the two sides of the same permanent magnet are mirror-symmetrically arranged, one end of the magnetic separation groove is connected with the permanent magnet, the other end of the magnetic separation groove extends towards the primary direction and expands towards the two sides of the permanent magnet, the other end of the magnetic separation groove protrudes from the edge of the permanent magnet, two through grooves are sequentially arranged at the end of each permanent magnet away from the primary, the part between the two through grooves is a first magnetic bridge, and the part between the end of the permanent magnet towards the primary and the edge of the secondary core is a second magnetic bridge.

Description

Technical Field

[0001] This invention belongs to the field of motor technology. Background Technology

[0002] Because permanent magnet synchronous linear motor systems do not have mechanical conversion devices, they have a simple structure, reliable operation, high control precision, and fast system response, making them widely applicable in fields such as CNC machine tools, petroleum, and maglev trains.

[0003] Most existing permanent magnet synchronous linear motors are surface-mounted permanent magnet synchronous linear motors, using direct-axis current I. d =0 control, therefore the magnetic reluctance thrust of the motor cannot be utilized. To obtain greater electromagnetic thrust, surface-mounted permanent magnet synchronous linear motors generally have a larger no-load back electromotive force (E0). However, due to structural limitations, the number and arrangement of permanent magnets are less flexible than in built-in permanent magnet synchronous linear motors. When the speed exceeds the rated speed, due to the use of direct-axis current I... d The =0 control mode cannot adjust the direct axis demagnetizing current, and a large E0 value is not conducive to weakening the magnetism, so the speed operating range is small. Summary of the Invention

[0004] This invention addresses the problems of limited flexibility in the amount and arrangement of permanent magnets in current surface-mounted permanent magnet synchronous linear motors due to structural limitations, as well as the inability to utilize magnetic reluctance thrust and the small speed operating range. It provides an anti-salient pole permanent magnet synchronous linear motor and a rotary motor.

[0005] The anti-salient pole permanent magnet synchronous linear motor includes a primary stage 1 and a secondary stage, with an air gap 8 between them. The secondary stage includes a secondary core 2 and multiple permanent magnets 3. The multiple permanent magnets 3 are evenly arranged and embedded in the secondary core 2 along the direction of movement of the secondary core 2. The magnetization direction of the permanent magnets 3 is the same as the direction of movement of the secondary core 2. Each permanent magnet 3 has N layers of magnetic isolation grooves 5 on both sides, where N is a positive integer. The magnetic isolation grooves 5 on both sides of the same permanent magnet 3 are mirror-symmetrically arranged. One end of the magnetic isolation groove 5 is connected to the permanent magnet 3, and the other end of the magnetic isolation groove 5 extends towards the primary stage 1 and spreads out to both sides of the permanent magnet 3. The other end of the magnetic isolation groove 5 protrudes beyond the edge of the permanent magnet 3. Each permanent magnet 3 has two through grooves 4 sequentially arranged at the end away from the primary stage 1. The part between the two through grooves 4 is the first magnetic bridge 6, and the part between the end of the permanent magnet 3 facing the primary stage 1 and the edge of the secondary core 2 is the second magnetic bridge 7.

[0006] Furthermore, the aforementioned through groove 4 is filled with permanent magnet material or non-magnetic material.

[0007] Furthermore, the aforementioned permanent magnet material is a rare-earth permanent magnet or a non-rare-earth permanent magnet.

[0008] Furthermore, the side adjacent to the primary core 1 of the secondary core 2 includes 2p sequentially connected arc segments, where p is the number of pole pairs, and the air gap width corresponding to the magnetic isolation groove 5 is smaller than the air gap width corresponding to the permanent magnet 3.

[0009] Furthermore, the magnetic isolation groove 5 is filled with a non-magnetic material, or the magnetic isolation groove 5 is partially filled with a permanent magnet material.

[0010] Furthermore, the magnetization direction of the permanent magnet material in the aforementioned magnetic isolation groove 5 is either the thickness direction of the permanent magnet material or the thickness direction of the secondary iron core 2.

[0011] Furthermore, the permanent magnet material filling the through groove 4 is connected in series with the magnetic circuit of the permanent magnet material in the magnetic isolation groove 5.

[0012] Furthermore, the permanent magnet 3 is divided into several small segments, all of which are arranged in a direction perpendicular to the magnetization direction, and the part between two adjacent small segments is the third magnetic bridge 9.

[0013] Furthermore, the aforementioned magnetic shielding groove 5 is arc-shaped or zigzag-shaped.

[0014] The anti-salient pole permanent magnet synchronous rotary motor includes a stator 1-1 and a rotor. The stator 1-1 is coaxially sleeved on the outside of the rotor, and an air gap 8 is left between the stator 1-1 and the rotor. The rotor includes a rotor core 1-2 and multiple permanent magnets 3. The multiple permanent magnets 3 are evenly arranged around the rotor core 1-2 and embedded in the rotor core 1-2. The magnetization direction of the permanent magnets 3 is tangential to the rotor core 1-2. Each permanent magnet 3 has N layers of magnetic isolation slots 5 on both sides, where N is a positive integer. The magnetic isolation slots 5 on both sides of the same permanent magnet 3 are mirror symmetrical. The magnetic isolation groove 5 is configured such that one end facing the center of the rotor core 1-2 is connected to the permanent magnet 3, and the other end of the magnetic isolation groove 5 extends towards the outer circumference of the rotor core 1-2 and spreads out to both sides of the permanent magnet 3. The other end of the magnetic isolation groove 5 protrudes beyond the edge of the permanent magnet 3. Each permanent magnet 3 has two through grooves 4 sequentially provided at one end facing the center of the rotor core 1-2. The part between the two through grooves 4 is the first magnetic bridge 6, and the part between the end of the permanent magnet 3 facing the outer circumference of the rotor core 1-2 and the edge of the rotor core 1-2 is the second magnetic bridge 7.

[0015] The anti-salient pole permanent magnet synchronous linear motor described in this invention can utilize the motor's magnetic reluctance thrust, and the design of the amount and form of permanent magnets is more flexible. Due to the magnetizing effect of the direct-axis armature current, the E0 design can be lower than that of the surface-mount structure. At the same time, the built-in anti-salient pole structure has a large direct-axis inductance value, resulting in a smaller field weakening current compared to ordinary salient pole permanent magnet synchronous linear motors under the same air gap magnetic flux density, which is more conducive to improving the speed operating range. The anti-salient pole permanent magnet synchronous linear motor described in this invention can improve the total electromagnetic thrust and also widen the motor's speed regulation range.

[0016] The anti-salient pole permanent magnet synchronous rotary motor of this invention can obtain positive reluctance torque by applying a small value of positive direct-axis current, and the design of the amount and form of permanent magnets is more flexible. Due to the magnetizing effect of the direct-axis armature current, the E0 design can be lower than that of the surface-mount structure. At the same time, the built-in anti-salient pole structure has a large direct-axis inductance value, and under the same air gap magnetic flux density, it has a smaller field weakening current compared with ordinary salient pole permanent magnet synchronous motors, which is more conducive to improving the speed operating range. The anti-salient pole permanent magnet synchronous rotary motor of this invention can improve the total electromagnetic torque and also widen the speed regulation range of the motor. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the anti-salient pole permanent magnet synchronous linear motor described in Specific Implementation Method 1;

[0018] Figure 2 This is a schematic diagram of the anti-salient pole permanent magnet synchronous linear motor described in Specific Implementation Method 2;

[0019] Figure 3 This is a schematic diagram of the anti-salient pole permanent magnet synchronous linear motor described in Specific Implementation Method 3;

[0020] Figure 4 This is a schematic diagram of the anti-salient pole permanent magnet synchronous linear motor described in Specific Implementation Method 4;

[0021] Figure 5 This is a schematic diagram of the anti-salient pole permanent magnet synchronous linear motor described in Specific Implementation Method 5;

[0022] Figure 6 This is a schematic diagram of the anti-salient pole permanent magnet synchronous rotating motor described in Specific Implementation Method Six.

[0023] Primary 1, Secondary core 2, Permanent magnet 3, Through slot 4, Magnetic isolation slot 5, First magnetic bridge 6, Second magnetic bridge 7, Air gap 8, Third magnetic bridge 9, Stator 1-1, Rotor core 1-2. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0025] Specific implementation method one: Refer to Figure 1 This implementation method will be described in detail. Figure 1The diagram shows a front view of the anti-salient pole permanent magnet synchronous linear motor described in this embodiment. The motor includes a primary stage 1 arranged along a linear path and a secondary stage capable of moving along the same path, with an air gap 8 between the primary stage 1 and the secondary stage. The primary stage 1 includes a primary core, winding slots, and an armature winding embedded in the winding slots.

[0026] The secondary stage includes a secondary core 2 and multiple permanent magnets 3. The edge of the secondary core 2 adjacent to the primary core 1 consists of 2p sequentially connected arc segments, where p is the number of pole pairs. The multiple permanent magnets 3 are evenly arranged and embedded within the secondary core 2 along its direction of movement. The magnetization direction of the permanent magnets 3 is the same as the direction of movement of the secondary core 2. Each permanent magnet 3 has a magnetically shielding groove 5 on both sides. The magnetically shielding groove 5 is a zigzag groove formed by connecting two straight groove segments. The magnetically shielding grooves 5 on both sides of the same permanent magnet 3 are mirror-symmetrically arranged. One end of the magnetically shielding groove 5 is connected to the permanent magnet 3, and the other end extends towards the primary core 1, spreading out to both sides of the permanent magnet 3 and protruding beyond its edge. The air gap width corresponding to the magnetically shielding groove 5 is smaller than the air gap width corresponding to the permanent magnet 3. Specifically, the connection point (lowest point of the arc) between the end of the permanent magnet 3 facing the primary and the edge of the secondary core 2 of two adjacent arcs is directly opposite, and the end of the magnetic isolation groove 5 facing the primary is directly opposite the most prominent point of an arc on the edge of the secondary core 2. Each permanent magnet 3 has two through slots 4 sequentially arranged at the end furthest from the primary 1. The through slots 4 are filled with permanent magnetic material or non-magnetic material. The permanent magnetic material is a rare-earth permanent magnet (such as neodymium iron boron) or a non-rare-earth permanent magnet (such as ferrite). The portion between the two through slots 4 forms the first magnetic bridge 6; the portion between the end of the permanent magnet 3 facing the primary 1 and the edge of the secondary core 2 forms the second magnetic bridge 7.

[0027] In this embodiment, the magnetic isolation groove 5 can be an empty groove or filled entirely with non-magnetic material in practical applications. As a magnetic barrier in the quadrature-axis magnetic circuit, the magnetic isolation groove 5 has a large magnetic reluctance, which can reduce the quadrature-axis inductance and increase the anti-salient pole ratio of the motor (note: here, the anti-salient pole ratio refers to the ratio of the direct-axis inductance to the quadrature-axis inductance), thus improving the magnetic reluctance thrust. Furthermore, the processing technology of the zigzag groove in this embodiment is simple. If permanent magnet material is placed in part of the groove, the magnetization of rectangular permanent magnet material is more convenient, simpler, and less costly.

[0028] In this embodiment, the anti-salient pole permanent magnet synchronous linear motor is a single-sided flat plate structure or a double-sided flat plate structure.

[0029] Specific Implementation Method Two: Refer to Figure 2 This implementation method will be described in detail. Figure 2 The diagram shows a front view of the anti-salient pole permanent magnet synchronous linear motor described in this embodiment. The motor includes a primary stage 1 arranged along a linear path and a secondary stage capable of moving along the same path, with an air gap 8 between the primary stage 1 and the secondary stage. The primary stage 1 includes a primary core, winding slots, and an armature winding embedded in the winding slots.

[0030] The secondary stage includes a secondary core 2 and multiple permanent magnets 3. The edge of the secondary core 2 adjacent to the primary core 1 consists of 2p sequentially connected arc segments, where p is the number of pole pairs. The multiple permanent magnets 3 are evenly arranged and embedded within the secondary core 2 along its direction of movement. The magnetization direction of the permanent magnets 3 is the same as the direction of movement of the secondary core 2. Each permanent magnet 3 has an arc-shaped magnetic isolation groove 5 on both sides. The magnetic isolation grooves 5 on both sides of the same permanent magnet 3 are mirror-symmetrically arranged. One end of the magnetic isolation groove 5 is connected to the permanent magnet 3, and the other end extends towards the primary core 1, spreading out to both sides of the permanent magnet 3 and protruding beyond its edge. The air gap width corresponding to the magnetic isolation groove 5 is smaller than the air gap width corresponding to the permanent magnet 3. Specifically, the end of the permanent magnet 3 facing the primary core aligns with the connection point (lowest point of the arc) of two adjacent arcs on the edge of the secondary core 2, and the end of the magnetic isolation groove 5 facing the primary core aligns with the most prominent point of one arc on the edge of the secondary core 2. Each permanent magnet 3 has two through slots 4 sequentially arranged at the end furthest from the primary core 1. The through slots 4 are filled with permanent magnet material or non-magnetic material. The permanent magnet material is a rare earth permanent magnet (such as neodymium iron boron) or a non-rare earth permanent magnet (such as ferrite). The portion between the two through slots 4 is the first magnetic bridge 6; the portion between the end of the permanent magnet 3 facing the primary core 1 and the edge of the secondary core 2 is the second magnetic bridge 7.

[0031] In this embodiment, the magnetic isolation groove 5 can be an empty groove or entirely filled with non-magnetic material in practical applications. The arc surface of the arc-shaped groove in this embodiment is gentler than that of a zigzag line. A zigzag line forms an angle between two segments, where the core will saturate. The arc-shaped groove, however, does not have an angle, thus improving the core saturation at the angle formed by the zigzag groove. Alternatively, the magnetic isolation groove 5 can be partially filled with permanent magnet material. When the magnetic isolation groove 5 is partially filled with permanent magnet material, the magnetization direction of the permanent magnet material is the thickness direction of the permanent magnet material, the thickness direction of the secondary core 2, or the radial direction of the arc-shaped groove, such as... Figure 2 The direction indicated by the dashed arrow. Radial magnetization of the arc-shaped permanent magnet is slightly greater than parallel magnetization. The magnetic circuits of the permanent magnet material filling the through slot 4 and the permanent magnet material in the magnetic isolation slot 5 are connected in series.

[0032] In this embodiment, the anti-salient pole permanent magnet synchronous linear motor is a single-sided flat plate structure or a double-sided flat plate structure.

[0033] Specific Implementation Method Three: Refer to Figure 3 This implementation method will be described in detail. Figure 3 The diagram shows a front view of the anti-salient pole permanent magnet synchronous linear motor described in this embodiment. The motor includes a primary stage 1 arranged along a linear path and a secondary stage capable of moving along the same path, with an air gap 8 between the primary stage 1 and the secondary stage. The primary stage 1 includes a primary core, winding slots, and an armature winding embedded in the winding slots.

[0034] The secondary stage includes a secondary core 2 and multiple permanent magnets 3. The side of the secondary core 2 adjacent to the primary core 1 consists of 2p sequentially connected arc segments, where p is the number of pole pairs. The multiple permanent magnets 3 are evenly arranged and embedded within the secondary core 2 along the direction of movement of the secondary core 2. The magnetization direction of the permanent magnets 3 is the same as the direction of movement of the secondary core 2. The permanent magnets 3 are divided into two small segments, which are arranged perpendicular to the magnetization direction, and the part between the two segments is the third magnetic bridge 9. Compared with the permanent magnets 3, the magnetic reluctance of the core at the third magnetic bridge 9 is much smaller than that of the permanent magnets 3. The third magnetic bridge 9 provides a smaller magnetic reluctance for the direct-axis magnetic circuit, which is beneficial to increasing the direct-axis inductance value, improving the speed operating range of the motor, and increasing the anti-salient pole ratio of the motor, which is beneficial to improving the magnetic reluctance thrust.

[0035] Each permanent magnet 3 has a magnetic isolation groove 5 on both sides. The magnetic isolation groove 5 is a zigzag groove formed by connecting two straight grooves. The magnetic isolation grooves 5 on both sides of the same permanent magnet 3 are arranged in a mirror symmetrical manner. One end of the magnetic isolation groove 5 is connected to the permanent magnet 3, and the other end of the magnetic isolation groove 5 extends towards the primary 1 and spreads out to both sides of the permanent magnet 3, protruding beyond the edge of the permanent magnet 3. The air gap width corresponding to the magnetic isolation groove 5 is smaller than the air gap width corresponding to the permanent magnet 3. Specifically, the connection point (the lowest point of the arc) between the end of the permanent magnet 3 facing the primary and the edge of the secondary core 2 is directly opposite, and the end of the magnetic isolation groove 5 facing the primary is directly opposite the most protruding point of one arc of the edge of the secondary core 2. Each permanent magnet 3 has two through grooves 4 sequentially provided at the end away from the primary 1. The through grooves 4 are filled with permanent magnet material or non-magnetic material. The permanent magnet material is a rare earth permanent magnet (such as neodymium iron boron) or a non-rare earth permanent magnet (such as ferrite). The portion between the two through slots 4 is the first magnetic bridge 6; the portion between the end of the permanent magnet 3 facing the primary 1 and the edge of the secondary core 2 is the second magnetic bridge 7.

[0036] In this embodiment, the magnetic isolation groove 5 can be an empty groove or filled entirely with non-magnetic material in practical applications. As a magnetic barrier in the quadrature-axis magnetic circuit, the magnetic isolation groove 5 has a large magnetic reluctance, which can reduce the quadrature-axis inductance and increase the anti-salient pole ratio of the motor (note: here, the anti-salient pole ratio refers to the ratio of the direct-axis inductance to the quadrature-axis inductance), thus improving the magnetic reluctance thrust. Furthermore, the processing technology of the zigzag groove in this embodiment is simple. If permanent magnet material is placed in part of the groove, the magnetization of rectangular permanent magnet material is more convenient, simpler, and less costly.

[0037] In this embodiment, the anti-salient pole permanent magnet synchronous linear motor is a single-sided flat plate structure or a double-sided flat plate structure.

[0038] Specific Implementation Method Four: Refer to Figure 4 This implementation method will be described in detail. Figure 4The diagram shows a front view of the anti-salient pole permanent magnet synchronous linear motor described in this embodiment. The motor includes a primary stage 1 arranged along a linear path and a secondary stage capable of moving along the same path, with an air gap 8 between the primary stage 1 and the secondary stage. The primary stage 1 includes a primary core, winding slots, and an armature winding embedded in the winding slots.

[0039] The secondary stage includes a secondary core 2 and multiple permanent magnets 3. The side of the secondary core 2 adjacent to the primary core 1 consists of 2p sequentially connected arc segments, where p is the number of pole pairs. The multiple permanent magnets 3 are evenly arranged and embedded within the secondary core 2 along its direction of movement. The magnetization direction of the permanent magnets 3 is the same as the direction of movement of the secondary core 2. Each permanent magnet 3 has two layers of arc-shaped magnetic isolation slots 5 on both sides. The magnetic isolation slots 5 act as magnetic barriers in the quadrature-axis magnetic circuit. The greater the magnetic resistance of the magnetic isolation slots 5, the smaller the quadrature-axis inductance, which is more conducive to improving the anti-salient pole ratio and increasing the magnetic reluctance thrust. Under the same length conditions, the magnetic resistance of the double-layer magnetic isolation slots is twice that of the single-layer magnetic isolation slots, and its quadrature-axis inductance is smaller, the anti-salient pole ratio is larger, and the magnetic reluctance thrust of the linear motor is better than that of the single-layer magnetic isolation slot structure, which is beneficial to improving the electromagnetic thrust. The magnetic isolation slots 5 on both sides of the same permanent magnet 3 are arranged in a mirror-symmetrical manner. One end of the magnetic isolation groove 5 is connected to the permanent magnet 3, and the other end of the magnetic isolation groove 5 extends towards the primary core 1 and spreads out to both sides of the permanent magnet 3, protruding beyond the edge of the permanent magnet 3. The air gap width corresponding to the magnetic isolation groove 5 is smaller than the air gap width corresponding to the permanent magnet 3. Specifically, the connection point (lowest point of the arc) between the end of the permanent magnet 3 facing the primary core and the edge of the secondary core 2 is directly opposite, and the most protruding point of one arc of the edge of the magnetic isolation groove 5 facing the primary core is directly opposite. Each permanent magnet 3 has two through grooves 4 sequentially provided at the end away from the primary core 1. The through grooves 4 are filled with permanent magnet material or non-magnetic material. The permanent magnet material is a rare earth permanent magnet (such as neodymium iron boron) or a non-rare earth permanent magnet (such as ferrite). The part between the two through grooves 4 is the first magnetic bridge 6; the part between the end of the permanent magnet 3 facing the primary core 1 and the edge of the secondary core 2 is the second magnetic bridge 7.

[0040] In this embodiment, the magnetic isolation groove 5 can be an empty groove, or its interior can be entirely filled with non-magnetic material, or it can be partially filled with permanent magnet material. When the magnetic isolation groove 5 is partially filled with permanent magnet material, the magnetization direction of the permanent magnet material is the thickness direction of the permanent magnet material or the thickness direction of the secondary iron core 2, such as... Figure 4 The direction indicated by the dashed arrow. The permanent magnet material filling the through slot 4 is connected in series with the permanent magnet material in the magnetic shielding slot 5.

[0041] In this embodiment, the anti-salient pole permanent magnet synchronous linear motor is a single-sided flat plate structure or a double-sided flat plate structure.

[0042] Specific Implementation Method Five: Refer to Figure 5 This implementation method will be described in detail. Figure 5The diagram shows a front view of the anti-salient pole permanent magnet synchronous linear motor described in this embodiment. The motor includes a primary stage 1 arranged along a linear path and a secondary stage capable of moving along the same path, with an air gap 8 between the primary stage 1 and the secondary stage. The primary stage 1 includes a primary core, winding slots, and an armature winding embedded in the winding slots.

[0043] The secondary stage includes a secondary core 2 and multiple permanent magnets 3. The edge of the secondary core 2 adjacent to the primary core 1 consists of 2p sequentially connected arc segments, where p is the number of pole pairs. The multiple permanent magnets 3 are evenly arranged and embedded within the secondary core 2 along its direction of movement. The magnetization direction of the permanent magnets 3 is the same as the direction of movement of the secondary core 2. Each permanent magnet 3 has a magnetically shielding groove 5 on both sides. The magnetically shielding groove 5 is a zigzag groove formed by connecting two straight groove segments. The magnetically shielding grooves 5 on both sides of the same permanent magnet 3 are mirror-symmetrically arranged. One end of the magnetically shielding groove 5 is connected to the permanent magnet 3, and the other end extends towards the primary core 1, spreading out to both sides of the permanent magnet 3 and protruding beyond its edge. The air gap width corresponding to the magnetically shielding groove 5 is smaller than the air gap width corresponding to the permanent magnet 3. Specifically, the connection point (lowest point of the arc) between the end of the permanent magnet 3 facing the primary and the edge of the secondary core 2 of two adjacent arcs is directly opposite, and the end of the magnetic isolation groove 5 facing the primary is directly opposite the most prominent point of an arc on the edge of the secondary core 2. Each permanent magnet 3 has two through slots 4 sequentially arranged at the end furthest from the primary 1. The through slots 4 are filled with permanent magnetic material or non-magnetic material. The permanent magnetic material is a rare-earth permanent magnet (such as neodymium iron boron) or a non-rare-earth permanent magnet (such as ferrite). The portion between the two through slots 4 forms the first magnetic bridge 6; the portion between the end of the permanent magnet 3 facing the primary 1 and the edge of the secondary core 2 forms the second magnetic bridge 7.

[0044] In this embodiment, the middle section of the magnetic isolation groove 5 is filled with permanent magnet material, and the magnetization direction of the permanent magnet material is either the thickness direction of the permanent magnet material or the thickness direction of the secondary iron core 2, such as... Figure 5 The direction indicated by the dashed arrow. The permanent magnet material filling the through slot 4 is connected in series with the permanent magnet material in the magnetic isolation slot 5. Placing permanent magnet material in the magnetic isolation slot 5 increases the flexibility in the amount and form design of the secondary permanent magnets. Compared with leaving the slot empty, placing permanent magnet material inside can further improve the permanent magnet flux linkage, which is beneficial to improving the electromagnetic thrust.

[0045] In this embodiment, the anti-salient pole permanent magnet synchronous linear motor is a single-sided flat plate structure or a double-sided flat plate structure.

[0046] First, this invention overcomes the limitations of surface-mounted permanent magnet synchronous linear motors, which cannot utilize reluctance thrust and cannot further increase the amount of permanent magnets to enhance the air gap magnetic field due to the surface-mounted structure. The specific principle is as follows:

[0047] Neglecting stator resistance, the electromagnetic thrust equation of a permanent magnet synchronous linear motor is:

[0048]

[0049] In the formula, F em The electromagnetic thrust of the permanent magnet synchronous linear motor is p, where p is the number of pole pairs and ψ is the electromagnetic thrust. f For permanent magnet flux linkage, L d For a direct-axis inductor, L q For quadrature axis inductance, i d For direct-axis current, i q Let τ be the quadrature-axis current and τ be the pole distance.

[0050] Electromagnetic thrust comprises two components: permanent magnet thrust and reluctance thrust. For surface-mounted salient-pole permanent magnet synchronous linear motors, only permanent magnet thrust is present; reluctance thrust is absent. The motor's electromagnetic thrust F... em The expression is:

[0051]

[0052] For an anti-salient pole permanent magnet synchronous linear motor, the electromagnetic thrust includes permanent magnet thrust and reluctance thrust. The anti-salient pole permanent magnet synchronous linear motor incorporates a magnetic bridge on the direct-axis magnetic circuit to increase the direct-axis inductance, and a magnetic barrier on the quadrature-axis magnetic circuit to reduce the quadrature-axis inductance. Simultaneously, a non-uniform air gap length is used to ensure that the direct-axis inductance is greater than the quadrature-axis inductance. The applied direct-axis current i... d A positive reluctance thrust can be obtained by using a positive magnet, and the armature's function is to amplify the magnetism. Properly matching the permanent magnet thrust and reluctance thrust is beneficial for improving the electromagnetic thrust of a permanent magnet synchronous linear motor.

[0053] Surface-mounted permanent magnet synchronous linear motors only provide permanent magnet thrust. When the pole arc of the permanent magnet is too large, it can cause significant inter-pole magnetic leakage. The surface-mounted structure limits the ability to increase thrust density by further increasing the amount of permanent magnets. However, the built-in anti-salient pole permanent magnet synchronous linear motor proposed in this invention features a built-in permanent magnet structure magnetized along the secondary movement direction, which has a certain magnetizing effect. The amount and arrangement of permanent magnets are flexible, which is beneficial for further improving thrust density.

[0054] Secondly, anti-salient pole permanent magnet synchronous linear motors can effectively improve the motor's speed operating range; compared with surface-mounted permanent magnet synchronous linear motors, they can achieve field weakening control; compared with salient pole permanent magnet synchronous linear motors, they require less direct-axis demagnetizing current under the same speed conditions, and the permanent magnets are less prone to demagnetization. These will be explained in detail below:

[0055] 1. Compared to surface-mounted permanent magnet synchronous linear motors, anti-salient pole permanent magnet synchronous linear motors have a wider speed range. Surface-mounted linear motors typically use a higher permanent magnet flux linkage ψ to achieve greater electromagnetic thrust. fThe design is relatively large. When the motor speed exceeds the rated speed, the phase voltage is limited by the voltage limit and the magnetization cannot be weakened, resulting in a small speed range. Because the armature winding of the anti-salient pole structure is magnetically enhanced when operating below the rated speed, under the same electromagnetic thrust, ψ f The design values ​​are generally lower than those of surface-mount structures, which is more conducive to improving the speed range. At the same time, the direct-axis inductance and quadrature-axis inductance of the anti-salient pole permanent magnet synchronous linear motor are not equal, which can achieve a wider speed range by applying a negative demagnetizing current.

[0056] 2. Compared to salient-pole permanent magnet synchronous linear motors, anti-salient-pole permanent magnet synchronous linear motors require less direct-axis demagnetizing current under the same speed conditions, and the permanent magnets are less prone to demagnetization. Because the direct-axis inductance of a salient-pole permanent magnet synchronous linear motor is smaller than its quadrature-axis inductance, a smaller negative direct-axis demagnetizing current is applied at rated speed to obtain positive reluctance torque. When the speed exceeds the rated speed, the negative demagnetizing current is increased to obtain a wider field-weakening speed range. Compared to salient-pole permanent magnet synchronous linear motors, the E0 of an anti-salient-pole permanent magnet synchronous linear motor is smaller under the same terminal voltage conditions. The direct-axis inductance of an anti-salient-pole permanent magnet synchronous linear motor is greater than its quadrature-axis inductance; a small positive direct-axis current is sufficient to ensure positive reluctance torque. Therefore, when the speed exceeds the rated speed, the direct-axis current gradually decreases from a positive value to 0, then to a negative value, and gradually increases to the negative rated current value. Compared to salient-pole permanent magnet synchronous linear motors, the field-weakening current required to reach the same speed value is smaller. In other words, under the same weak magnetic current conditions, the anti-salient pole permanent magnet synchronous linear motor achieves a wider speed range than the salient pole permanent magnet synchronous linear motor.

[0057] In summary, compared with surface-mounted permanent magnet synchronous linear motors, this invention can utilize the reluctance thrust of linear motors, and has fewer restrictions on the amount of permanent magnets used and a more flexible arrangement, which is beneficial for improving electromagnetic thrust. Furthermore, compared with surface-mounted or positive salient pole permanent magnet motors, the anti-salient pole permanent magnet synchronous motor has a larger direct-axis inductance and a relatively smaller no-load back EMF design value, which is beneficial for improving the motor's speed operating range. This motor is suitable for applications requiring larger electromagnetic thrust and a wider speed operating range.

[0058] Specific Implementation Method Six: Based on the above five specific implementation methods, a rotating motor structure can be further extended, as shown in the following figure. Figure 6 This implementation method will be described in detail. Figure 6 The diagram shows a front view of the anti-salient pole permanent magnet synchronous rotary motor described in this embodiment. The motor includes a stator 1-1 and a rotor. The stator 1-1 is coaxially sleeved around the rotor, and an air gap 8 is provided between the stator 1-1 and the rotor. The stator 1-1 includes a stator core, winding slots, and armature windings embedded in the winding slots.

[0059] The rotor includes a rotor core 1-2 and multiple permanent magnets 3. The permanent magnets 3 are evenly arranged circumferentially around the rotor core 1-2 and embedded within it. The magnetization direction of the permanent magnets 3 is tangential to the rotor core 1-2. Each permanent magnet 3 has a magnetic isolation groove 5 on both sides. The magnetic isolation grooves 5 on both sides of the same permanent magnet 3 are mirror-symmetrically arranged. One end of the magnetic isolation groove 5 facing the center of the rotor core 1-2 is connected to the permanent magnet 3, and the other end of the magnetic isolation groove 5 extends outwards towards the outer circumference of the rotor core 1-2 and spreads to both sides of the permanent magnet 3, with the other end protruding beyond the edge of the permanent magnet 3. Each permanent magnet 3 has two sequentially arranged through slots 4 at the end facing the center of the rotor core 1-2. The through slots 4 are filled with permanent magnetic material or non-magnetic material. The permanent magnetic material is a rare-earth permanent magnet (such as neodymium iron boron) or a non-rare-earth permanent magnet (such as ferrite). The portion between the two through slots 4 is the first magnetic bridge 6, and the portion between the end of the permanent magnet 3 facing the outer circumference of the rotor core 1-2 and the edge of the rotor core 1-2 is the second magnetic bridge 7.

[0060] In this embodiment, the magnetic isolation groove 5 is filled with a non-magnetic material, or the magnetic isolation groove 5 is partially filled with permanent magnet material. The magnetization direction of the permanent magnet material in the magnetic isolation groove 5 is either the thickness direction of the permanent magnet material or the radial direction of the rotor core 1-2, such as... Figure 6 The direction indicated by the dashed arrow. The permanent magnet material filling the through slot 4 is connected in series with the permanent magnet material in the magnetic shielding slot 5.

[0061] While the invention has been described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the invention. Therefore, it should be understood that many modifications can be made to the exemplary embodiments, and other arrangements can be designed without departing from the spirit and scope of the invention as defined by the appended claims. It should be understood that different dependent claims and features described herein can be combined in ways different from those described in the original claims. It is also understood that features described in conjunction with individual embodiments can be used in other described embodiments.

Claims

1. An anti-salient pole permanent magnet synchronous linear motor, comprising a primary (1) and a secondary, wherein an air gap (8) is provided between the primary (1) and the secondary, characterized in that, The secondary stage includes: a secondary core (2) and multiple permanent magnets (3). Multiple permanent magnets (3) are evenly arranged and embedded in the secondary iron core (2) along the direction of movement of the secondary iron core (2). The magnetization direction of the permanent magnets (3) is in the same direction as the direction of movement of the secondary iron core (2). Each permanent magnet (3) has N layers of magnetic isolation grooves (5) on both sides, where N is a positive integer. The magnetic isolation grooves (5) on both sides of the same permanent magnet (3) are mirror-symmetrically arranged. One end of the magnetic isolation groove (5) is connected to the permanent magnet (3), and the other end of the magnetic isolation groove (5) extends towards the primary (1) and spreads out to both sides of the permanent magnet (3). The other end of the magnetic isolation groove (5) protrudes beyond the edge of the permanent magnet (3). Each permanent magnet (3) has two through slots (4) sequentially provided at the end away from the primary (1). The part between the two through slots (4) is the first magnetic bridge (6), and the part between the end of the permanent magnet (3) facing the primary (1) and the edge of the secondary core (2) is the second magnetic bridge (7). The secondary core (2) and the primary core (1) are adjacent to each other by 2p sequentially connected arcs, where p is the pole pair number. The air gap width corresponding to the magnetic isolation groove (5) is smaller than the air gap width corresponding to the permanent magnet (3).

2. The anti-salient pole permanent magnet synchronous linear motor according to claim 1, characterized in that, The through groove (4) is filled with permanent magnet material or non-magnetic material.

3. The anti-salient pole permanent magnet synchronous linear motor according to claim 2, characterized in that, The permanent magnet material is either a rare-earth permanent magnet or a non-rare-earth permanent magnet.

4. The anti-salient pole permanent magnet synchronous linear motor according to claim 2, characterized in that, The magnetic shielding groove (5) is filled with a non-magnetic material, or the magnetic shielding groove (5) is partially filled with permanent magnet material.

5. The anti-salient pole permanent magnet synchronous linear motor according to claim 4, characterized in that, The magnetization direction of the permanent magnet material in the magnetic isolation groove (5) is the thickness direction of the permanent magnet material or the thickness direction of the secondary iron core (2).

6. The anti-salient pole permanent magnet synchronous linear motor according to claim 4, characterized in that, The permanent magnet material filling the through groove (4) is connected in series with the magnetic circuit of the permanent magnet material in the magnetic isolation groove (5).

7. The anti-salient pole permanent magnet synchronous linear motor according to claim 1, characterized in that, The permanent magnet (3) is divided into several segments, all of which are arranged in a direction perpendicular to the magnetization direction. The part between two adjacent segments is the third magnetic bridge (9).

8. The anti-salient pole permanent magnet synchronous linear motor according to claim 1, characterized in that, The magnetic isolation groove (5) is arc-shaped or zigzag-shaped.

9. A reverse salient pole permanent magnet synchronous rotary motor, comprising a stator (1-1) and a rotor, wherein the stator (1-1) is coaxially sleeved on the outside of the rotor, and an air gap (8) is provided between the stator (1-1) and the rotor, characterized in that, The rotor includes a rotor core (1-2) and multiple permanent magnets (3). Multiple permanent magnets (3) are evenly arranged and embedded in the rotor core (1-2) along the circumference. The magnetization direction of the permanent magnets (3) is tangential to the rotor core (1-2). Each permanent magnet (3) has N layers of magnetic isolation grooves (5) on both sides, where N is a positive integer. The magnetic isolation grooves (5) on both sides of the same permanent magnet (3) are mirror-symmetrically arranged. One end of the magnetic isolation groove (5) facing the center of the rotor core (1-2) is connected to the permanent magnet (3), and the other end of the magnetic isolation groove (5) extends towards the outer circumference of the rotor core (1-2) and spreads out to both sides of the permanent magnet (3). The other end of the magnetic isolation groove (5) protrudes beyond the edge of the permanent magnet (3). Each permanent magnet (3) has two through slots (4) sequentially provided at one end facing the center of the rotor core (1-2). The part between the two through slots (4) is the first magnetic bridge (6), and the part between the end of the permanent magnet (3) facing the outer circumference of the rotor core (1-2) and the edge of the rotor core (1-2) is the second magnetic bridge (7). The secondary core (2) and the primary core (1) are adjacent to each other by 2p sequentially connected arcs, where p is the pole pair number. The air gap width corresponding to the magnetic isolation groove (5) is smaller than the air gap width corresponding to the permanent magnet (3).

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