Wound radial laminated rotor structure of synchronous reluctance electric motor and design method

Abstract

The present invention relates to the technical field of synchronous reluctance electric motors. Provided are a wound radial laminated rotor structure of a synchronous reluctance electric motor and a design method. The rotor structure comprises a rotor support, a rotor core, a fixing bolt and a pressing block, wherein the rotor core is formed by alternatingly and radially laminating magnetically-conductive layers and non-magnetically-conductive layers, the rotor core is fixed to the rotor support by means of the fixing bolt and the pressing block, the ratio of the thickness of the magnetically-conductive layer to the thickness of the non-magnetically-conductive layer is smaller than 5:1, the magnetically-conductive layers and the non-magnetically-conductive layers of the rotor core are of a concentric circle structure, the magnetically-conductive layers and the non-magnetically-conductive layers of the rotor core are wound to form a circular ring, and the rotor core is divided into parts with the same number as poles of the electric motor by means of a separation process. The rotor structure breaks through a traditional axial structure, no air magnetic barrier is present on the rotor, and the rotor structure is connected to a high-strength support by means of a high-strength bolt, thereby achieving high mechanical strength, and adapting to a high-speed synchronous reluctance electric motor product.

Description

A wound radial laminated rotor structure and design method for a synchronous reluctance motor Technical Field

[0001] The present invention relates to the technical field of synchronous reluctance motors, and in particular to a synchronous reluctance motor wound radial laminated rotor structure and a design method thereof. Background Art

[0002] With the continuous innovation and rapid development of modern industry, electric motors, as a common electromechanical energy conversion device, are ubiquitous in all sectors of the national economy. Permanent magnet synchronous motors (PMSMs) are attracting increasing attention due to their compact structure, high energy density, and high efficiency. However, existing high-performance rare earth permanent magnet materials are expensive. As a result, a growing number of research institutes and manufacturers are seeking alternatives to PMSMs, hoping to reduce motor costs while maintaining excellent performance by utilizing ferrite or even eliminating the permanent magnet material.

[0003] The synchronous reluctance motor (SRM) is a high-performance electric motor with these characteristics. It primarily utilizes the uneven magnetic resistance of the rotor to generate electromagnetic torque, also known as a reactive synchronous motor. Its stator structure is essentially the same as that of a three-phase asynchronous motor, with the windings connected to an AC power source to generate a rotating magnetic field. The rotor is constructed from laminated silicon steel sheets, with multiple layers of magnetic barriers on the core and no starting winding. The motor generates electromagnetic torque due to the difference in magnetic resistance between the direct and quadrature axes, thereby achieving electromechanical energy conversion. The motor has no rotor copper loss, resulting in high efficiency. It also features a wide magnetic field-weakening speed regulation range and synchronous characteristics. It is a highly efficient, energy-efficient, and cost-effective motor suitable for a wide range of industrial equipment (such as fans and pumps) and electric vehicles.

[0004] The magnetic flux within a synchronous reluctance motor follows the "principle of minimum magnetic resistance" to form a closed loop, and the motor's output torque is positively correlated with the ratio of the quadrature-axis and direct-axis inductances (salient pole ratio). The synchronous reluctance motor rotor is the core component of the product and typically employs an axially laminated structure to achieve greater electromagnetic torque and improve the salient pole ratio. The rotor core is designed as a multi-layer magnetic barrier structure, and the rotor edge magnetic isolation bridge is a critical component of the rotor core, connecting the various magnetic conductive layers of the rotor core and significantly impacting motor performance. A narrower rotor edge magnetic isolation bridge improves motor performance. However, a narrow rotor edge magnetic isolation bridge can easily weaken the rotor structure, especially at high speeds, which can reduce motor reliability.

[0005] Patent 202121859841.X "A rotor and motor of a synchronous reluctance motor" sets the width of the magnetic isolation bridge corresponding to each magnetic barrier in each sub-pole magnetic barrier group to be different in order to improve the reliability of the permanent magnet assisted synchronous reluctance motor, thereby optimizing the rotor structure. However, this structure essentially reduces the sum of the widths of each magnetic bridge in the magnetic barrier group, but the wider magnetic isolation bridge will increase the leakage flux and affect the performance of the motor. At the same time, the strength of the motor rotor is equivalent to that of the original solution, which is not very suitable for high-speed synchronous reluctance motors. Patent 201520106652.3 "Rotor of a synchronous reluctance motor and a synchronous reluctance motor" adjusts the position of the magnetic isolation bridge at the edge of the rotor and adjusts the magnetic isolation bridge at the edge of the rotor to the middle of the magnetic barrier. Although this structure improves the performance of the motor, the strength of the motor cannot be guaranteed and cannot meet the requirements of a high-speed synchronous reluctance motor.

[0006] Summary of the Invention

[0007] The object of the present invention is to address the deficiencies of the above-mentioned prior art and to provide a synchronous reluctance motor wound radial laminated rotor structure and design method to solve the problem of improving the rotor structure performance.

[0008] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0009] In the first aspect, the present invention provides a wound radial laminated rotor structure of a synchronous reluctance motor, which includes a rotor support, a rotor core, fixing bolts and a pressure block. The rotor core is composed of radial laminates of alternating magnetic conductive layers and non-magnetic conductive layers. The rotor core is fixed to the rotor support by fixing bolts and a pressure block. The thickness ratio of the magnetic conductive layer to the non-magnetic conductive layer is less than 5:1. The magnetic conductive layer and the non-magnetic conductive layer of the rotor core are concentric circle structures, and are formed into a circular ring shape by winding the magnetic conductive layer and the non-magnetic conductive layer. The rotor core is divided into the same number of parts as the number of motor poles through a separation process.

[0010] Optionally, the material of the magnetic conductive layer of the rotor core is one of the following: silicon steel, steel; the material of the non-magnetic conductive layer of the rotor core is one of the following: polyester fiber, epoxy resin, high-strength plastic.

[0011] In a second aspect, the present invention provides a method for designing a wound radial laminated rotor structure of a synchronous reluctance motor. The method is used to design the wound radial laminated rotor structure of the synchronous reluctance motor according to the first aspect, and the method comprises:

[0012] Step A: radially layering the rotor core, wherein the magnetic conductive layers and the non-magnetic conductive layers of the rotor core are alternately stacked, the number of layers of the rotor core is 2n-1, the number of layers of the magnetic conductive layers is n, and the number of layers of the non-magnetic conductive layers is n-1, where n is an integer greater than 10.

[0013] Step B: Each magnetic conductive layer and non-magnetic conductive layer is in the shape of a ring. The outermost magnetic conductive layer is regarded as the first layer. The magnetic conductive layers are the second layer, the third layer, ..., the nth layer in the direction of the rotor center O1. Each layer is a concentric circle with the center as O2. The distance L between the rotor center O1 and the center O2 is o1o2 L o1o2 =D2sinα1 / 2sin(α1+α3)

[0014] Where:

[0015] D2 represents the outer diameter of the rotor, α1 represents the angle between AO1 and AO2, AO1 is the magnetic pole axis, point A is the intersection of the magnetic pole axis and the outer circle of the rotor, α3 represents the angle between O1B and O1O2, and point B is the intersection of the inner arc of the nth magnetic conductive layer and the outer circle of the rotor;

[0016] Step C, the magnetic pole arc coefficient k is determined by the angle α2 between O1C and O1O2. Point C is the intersection of the outer arc line of the first magnetic conductive layer and the outer circle of the rotor. k = 2(α4-α2) / 2α4 = (α4-α2) / α4

[0017] Where: α4 represents the angle between O1A and O1O2, α4 = 360 / p / 2;

[0018] p represents the number of motor poles;

[0019] Step D: The outer arc radius of the first magnetic conductive layer is

[0020] The inner arc radius r of the first magnetic permeable layer i1 =r1+T si ;

[0021] The outer arc radius of the second magnetic permeable layer r2 = r i1 +T n-c , the inner arc radius r of the second magnetic conductive layer i2 =r2+T si ;

[0022] The outer arc radius of the third magnetic permeable layer r3 = r i2 +T n-c , the inner arc radius r of the third magnetic conductive layer i3 =r3+T si ;

[0023] And so on.

[0024] The outer arc radius r of the n-1th magnetic conductive layer n-1 =r i(n-2) +T n-c , the inner arc radius r of the n-1th magnetic conductive layer i(n-1) =r n-1 +Tsi ;

[0025] The outer arc radius r of the nth magnetic conductive layer n =r i(n-1) +T n-c , the inner arc radius r of the nth magnetic conductive layer in =r n +T si ;

[0026] Step E: With O2 as the center, r1, r i1 The intersection of the two circles and the rotor is the first magnetic conductive layer. With O2 as the center, r2, r i2 Draw a diagram with radius, the intersection of the two circles and the rotor is the second magnetic conductive layer, the middle between the first and second magnetic conductive layers is the first non-magnetic conductive layer; and so on; take O2 as the center, and r n 、r in Draw a diagram for the radius. The intersection of the two circles and the rotor is the nth magnetic conductive layer, and the area between the n-1th magnetic conductive layer and the nth magnetic conductive layer is the n-1th non-magnetic conductive layer.

[0027] Step F: The middle part between the nth magnetic conductive layer and the rotating shaft is the rotor bracket, which is used to support the entire rotor core;

[0028] Step G, calculating the direct axis magnetic resistance of the motor, where the direct axis magnetic resistance of the motor includes the magnetic resistance of the rotor support, the magnetic resistance of the magnetic conductive layer, the magnetic resistance of the non-magnetic conductive layer, the magnetic resistance of the rotor clamping plate, and the magnetic resistance of the air gap;

[0029] Step H: Calculate the magnetic resistance R0 of the non-magnetic layer in the direct axis direction.

[0030] Where:

[0031] k0 represents the first correction coefficient;

[0032] υ0 represents the air magnetic resistivity;

[0033] S av Indicates the equivalent cross-sectional area of ​​the rotor core lamination along the length direction, S av =(S1+S2+...+S n ) / n, S1 is the area of ​​the arc surface where the midline of the first magnetic layer is located along the length direction, S1=(S o1 +S i1 ) / 2,S o1 is the lengthwise area of ​​the arc surface of the first magnetic permeable layer facing the center O2, S i1 is the area of ​​the arc surface of the first magnetic permeable layer facing away from the center O2 along the length direction, and so on. n The equivalent cross-sectional area of ​​the nth magnetic conductive layer along the length direction, Sn =(S on +S in ) / 2,S on S is the lengthwise area of ​​the arc surface of the nth magnetic conductive layer facing the center O2, in is the lengthwise area of ​​the arc surface of the nth magnetic conductive layer facing away from the center O2;

[0034] Step I: Calculate the direct-axis air gap reluctance R1 between the rotor clamping plate and the rotor core:

[0035] Where:

[0036] k1 represents the second correction coefficient, T d1 It represents the distance from the clamping plate to the outer diameter of the rotor in the straight axis direction, δ represents the air gap length,

[0037] S d1 Indicates the cross-sectional area of ​​the rotor clamp along the length direction;

[0038] Step J: Calculate the total direct-axis magnetic resistance R d : R d =R0+R1;

[0039] Step K: Calculate the quadrature-axis magnetic resistance R q :

[0040] Among them: k2 represents the third correction coefficient,

[0041] S q It represents the cross-sectional area of ​​the rotor core in the axial direction;

[0042] Step L: Calculate the motor salient pole ratio K dq :

[0043] Step M: Calculate the motor performance to determine a motor design solution that meets the preset goals.

[0044] Optionally, the thickness of each magnetic conductive layer is set to T si , T si The value of satisfies one of the following conditions: an integer multiple of 0.35 mm, an integer multiple of 0.5 mm, or the sum of any integer multiple of 0.35 mm and any integer multiple of 0.5 mm; the thickness of each non-magnetic conductive layer is set to T n-c , T n-c The value range is 0.1mm to 0.6mm.

[0045] Optionally, in step M, one of the following two calculation methods is selected for calculation:

[0046] The parameter R d 、Rq , K dq The calculation formula is compiled into the circuit calculation software, and the parameters α1, α2, α3, T si 、T n-c Input software to calculate motor performance indicators, including motor efficiency and power factor, and input the calculated performance indicators into electromagnetic field calculation software for iteration until convergence to determine a motor design solution that meets preset goals; or

[0047] By setting the parameters α1, α2, α3, T si 、T n-c A model was established using ANSYS electromagnetic field calculation software, and different step sizes and ranges were set. The motor efficiency was taken as the goal while taking into account the pulsating torque of the motor for optimization design, and finally a motor design scheme that met the goals was determined.

[0048] The beneficial effects of the present invention include:

[0049] The present invention provides a wound radially laminated rotor structure for a synchronous reluctance motor, including a rotor support, a rotor core, fixing bolts, and a pressure block. The rotor core is constructed from alternating radially laminated magnetic layers and non-magnetic layers. The fixing bolts and pressure block secure the rotor core to the rotor support. The thickness ratio of the magnetic layers to the non-magnetic layers is less than 5:1. The magnetic layers and non-magnetic layers of the rotor core are concentric circles, wound into a circular ring shape, and a separation process divides the rotor core into a number of sections equal to the number of motor poles. This rotor breaks away from the traditional axial structure, lacking an air magnetic barrier. It is connected to the high-strength support via high-strength bolts, resulting in high mechanical strength and suitability for high-speed synchronous reluctance motors. In motor design, this application reduces motor losses and torque ripple by adjusting parameters such as the thickness of the magnetic layers, the thickness of the non-magnetic layers, and the pole arc coefficient of the outermost magnetic layer, thereby increasing efficiency and power factor. The design method of this application offers the advantages of accurate calculation, rapid and convenient operation, short calculation cycles, and wide applicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0051] FIG1 shows a schematic structural diagram of a wound radial laminated rotor of a synchronous reluctance motor provided by an embodiment of the present invention;

[0052] 2A and 2B are schematic diagrams showing the structure of a rotor punching provided by an embodiment of the present invention;

[0053] FIG3 is a schematic diagram showing the equivalent cross-sectional area of ​​a magnetic conductive laminate along the length direction provided by an embodiment of the present invention;

[0054] FIG4 is a schematic diagram showing the cross-sectional area of ​​a rotor clamping plate along the length direction according to an embodiment of the present invention;

[0055] FIG5 is a schematic diagram showing the cross-axis cross-sectional area of ​​an air gap-through magnetic conductive laminate provided by an embodiment of the present invention;

[0056] FIG6 shows a schematic diagram of the H132-4 rotor punching structure provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0057] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0058] With the continuous innovation and rapid development of modern industry, electric motors, as a common electromechanical energy conversion device, are ubiquitous in all sectors of the national economy. Permanent magnet synchronous motors (PMSMs) are attracting increasing attention due to their compact structure, high energy density, and high efficiency. However, existing high-performance rare earth permanent magnet materials are expensive, prompting a growing number of research institutes and manufacturers to seek alternatives to PMSMs, hoping to reduce motor costs while maintaining excellent performance by utilizing ferrite or even eliminating the permanent magnet material. Synchronous reluctance motors (SRMs) are high-performance motors that exhibit these characteristics. They primarily utilize the uneven magnetic reluctance of the rotor to generate electromagnetic torque, also known as reactive synchronous motors. Their stator structure is essentially the same as that of a three-phase asynchronous motor, with windings connected to an AC power supply to generate a rotating magnetic field. The rotor is constructed of laminated silicon steel sheets with multiple layers of magnetic barriers on the core and no starting winding. The motor generates electromagnetic torque due to the difference in magnetic reluctance between the direct and quadrature axes, thereby achieving electromechanical energy conversion. This motor has no rotor copper loss, boasts high efficiency, a wide flux-weakening speed range, and synchronous characteristics. It is energy-efficient and cost-effective, suitable for widespread use in general-purpose industrial equipment (such as fans and pumps) and electric vehicles. The magnetic flux within a synchronous reluctance motor forms a closed loop, following the "minimum reluctance principle." The motor's output torque is positively correlated with the ratio of the quadrature-axis to the direct-axis inductance (saliency ratio). The rotor, the core component of a synchronous reluctance motor, typically employs an axially laminated structure to achieve greater electromagnetic torque and a high saliency ratio. The rotor core is designed with a multi-layered magnetic barrier structure. The rotor edge magnetic bridge is a critical component of the rotor core, connecting the various magnetically conductive layers of the rotor core and significantly impacting motor performance. Narrower rotor edge magnetic bridges improve motor performance. However, too narrow a rotor edge magnetic bridge can weaken the rotor structure, compromising reliability, especially at higher speeds.

[0059] To this end, the present invention provides a novel rotor structure and a design method thereof.

[0060] FIG1 shows a schematic diagram of the structure of a wound radial laminated rotor of a synchronous reluctance motor provided in an embodiment of the present invention; FIG2A and FIG2B show schematic diagrams of the structure of rotor punchings provided in an embodiment of the present invention.

[0061] In the first aspect, the present invention provides a wound radial laminated rotor structure of a synchronous reluctance motor, as shown in Figure 1 and Figures 2A and 2B. The rotor structure includes a rotor bracket, a rotor core, fixing bolts and a pressure block. The rotor core is composed of radial laminates of alternating magnetic conductive layers and non-magnetic conductive layers. The rotor core is fixed to the rotor bracket by fixing bolts and a pressure block. The thickness ratio of the magnetic conductive layer to the non-magnetic conductive layer is less than 5:1. The magnetic conductive layer and the non-magnetic conductive layer of the rotor core are concentric circle structures, and are formed into a circular ring shape by winding the magnetic conductive layer and the non-magnetic conductive layer. The rotor core is divided into the same number of parts as the number of motor poles through a separation process.

[0062] Optionally, the material of the magnetic conductive layer of the rotor core is one of the following: silicon steel, steel; the material of the non-magnetic conductive layer of the rotor core is one of the following: polyester fiber, epoxy resin, high-strength plastic.

[0063] This rotor breaks through the traditional axial structure. There is no air magnetic barrier on the rotor. At the same time, it is connected to the high-strength bracket through high-strength bolts. It has high mechanical strength and is suitable for high-speed synchronous reluctance motor products.

[0064] Compared with the traditional axial laminated core, the electromagnetic calculation method of the synchronous reluctance motor with a wound radial laminated rotor structure has greater particularity.

[0065] In a second aspect, the present invention provides a method for designing a wound radial laminated rotor structure of a synchronous reluctance motor. The method is used to design the wound radial laminated rotor structure of the synchronous reluctance motor according to the first aspect, and the method comprises:

[0066] Step A: The rotor core is radially layered, as shown in FIG2A and FIG2B , wherein the magnetic conductive layers and the non-magnetic conductive layers of the rotor core are alternately stacked. The number of layers of the rotor core is 2n-1, the number of magnetic conductive layers is n, and the number of non-magnetic conductive layers is n-1, where n is an integer greater than 10. The magnetic conductive layers and the non-magnetic conductive layers are alternately connected, i.e., a non-magnetic conductive layer is located between the two magnetic conductive layers. Optionally, the thickness of each magnetic conductive layer is set to T si , T si The value of satisfies one of the following conditions: an integer multiple of 0.35 mm, an integer multiple of 0.5 mm, or the sum of any integer multiple of 0.35 mm and any integer multiple of 0.5 mm, such as 0.35 mm, 0.7 mm, 0.85 mm, 1 mm, etc. The thickness of each non-magnetic conductive layer is set to T n-c , T n-c The value range is 0.1mm to 0.6mm.

[0067] Step B: Each magnetic conductive layer and non-magnetic conductive layer is in the shape of a ring. The outermost magnetic conductive layer is regarded as the first layer. The magnetic conductive layers are the second layer, the third layer, ..., the nth layer in the direction of the rotor center O1. Each layer is a concentric circle with the center as O2. The distance L between the rotor center O1 and the center O2 is o1o2 L o1o2 =D2sinα1 / 2sin(α1+α3)

[0068] Where:

[0069] D2 represents the outer diameter of the rotor, α1 represents the angle between AO1 and AO2, which is usually not less than 90°, AO1 is the magnetic pole axis, point A is the intersection of the magnetic pole axis and the outer circle of the rotor, α3 represents the angle between O1B and O1O2, and point B is the intersection of the inner arc of the nth magnetic conductive layer and the outer circle of the rotor; the rotor core is made by winding, and the winding thickness, that is, the radial stacking thickness of the rotor core, is determined by the thickness of the magnetic conductive layer Tsi, the thickness of the non-magnetic conductive layer Tn-c and the number of layers 2n-1. The rotor core can be divided into p parts, each of which has the same shape as a magnetic pole. This structure avoids the waste of effective core material.

[0070] Step C, the magnetic pole arc coefficient k is determined by the angle α2 between O1C and O1O2. Point C is the intersection of the outer arc line of the first magnetic conductive layer and the outer circle of the rotor. k = 2(α4-α2) / 2α4 = (α4-α2) / α4

[0071] Where: α4 represents the angle between O1A and O1O2, α4 = 360 / p / 2;

[0072] p represents the number of motor poles;

[0073] Step D: The outer arc radius of the first magnetic conductive layer is

[0074] The inner arc radius r of the first magnetic permeable layer i1 =r1+T si ;

[0075] The outer arc radius of the second magnetic permeable layer r2 = r i1 +T n-c , the inner arc radius r of the second magnetic conductive layer i2 =r2+T si ;

[0076] The outer arc radius of the third magnetic permeable layer r3 = r i2 +T n-c , the inner arc radius r of the third magnetic conductive layer i3 =r3+T si ;

[0077] And so on.

[0078] The outer arc radius r of the n-1th magnetic conductive layer n-1 =r i(n-2) +T n-c , the inner arc radius r of the n-1th magnetic conductive layer i(n-1) =r n-1 +T si ;

[0079] The outer arc radius r of the nth magnetic conductive layer n =r i(n-1) +T n-c, the inner arc radius r of the nth magnetic conductive layer in =r n +T si .

[0080] Step E: With O2 as the center, r1, r i1 The intersection of the two circles and the rotor is the first magnetic conductive layer. With O2 as the center, r2, r i2 Draw a diagram with radius, the intersection of the two circles and the rotor is the second magnetic conductive layer, the middle between the first and second magnetic conductive layers is the first non-magnetic conductive layer; and so on; take O2 as the center, and r n 、r in Draw a diagram for the radius. The intersection of the two circles and the rotor is the nth magnetic conductive layer, and the area between the n-1th magnetic conductive layer and the nth magnetic conductive layer is the n-1th non-magnetic conductive layer.

[0081] Step F: The middle part between the nth magnetic conductive layer and the rotating shaft is the rotor bracket, which is used to support the entire rotor core. The material can be high-strength magnetic conductive materials such as iron and steel;

[0082] Step G, calculating the direct-axis magnetic reluctance of the motor. The direct-axis magnetic reluctance of the motor includes the reluctance of the rotor bracket, the magnetic layer, the non-magnetic layer, the rotor clamping plate, and the air gap. The magnetic layer and the rotor bracket are made of magnetically conductive materials, and their reluctance is much smaller than that of air. Therefore, the direct-axis magnetic reluctance of the magnetic layer and the rotor bracket can be ignored. The reluctance of the non-magnetic material is similar to that of air, so the reluctance of air is used.

[0083] Step H: Calculate the magnetic resistance R0 of the non-magnetic layer in the direct axis direction.

[0084] Where:

[0085] k0 represents the first correction coefficient, and the calculation result k0 can be corrected using the electromagnetic field analysis of the simulation software;

[0086] υ0 represents the air magnetic resistivity;

[0087] S av Indicates the equivalent cross-sectional area of ​​the rotor core lamination along the length direction, S av =(S1+S2+...+S n ) / n, S1 is the area of ​​the arc surface where the midline of the first magnetic layer is located along the length direction, S1=(S o1 +S i1 ) / 2, as shown in Figure 3, S o1 is the lengthwise area of ​​the arc surface of the first magnetic permeable layer facing the center O2, S i1 is the area of ​​the arc surface of the first magnetic permeable layer facing away from the center O2 along the length direction, and so on. nThe equivalent cross-sectional area of ​​the nth magnetic conductive layer along the length direction, S n =(S on +S in ) / 2,S on is the lengthwise area of ​​the arc surface of the nth magnetic conductive layer facing the center O2, S in is the lengthwise area of ​​the arc surface of the nth magnetic conductive layer facing away from the center O2;

[0088] Step I: Calculate the direct-axis air gap reluctance R1 between the rotor clamping plate and the rotor core:

[0089] Where:

[0090] k1 represents the second correction coefficient, and the calculation result k1 can be corrected by using the electromagnetic field analysis of the simulation software, T d1 It represents the distance from the clamping plate to the outer diameter of the rotor in the straight axis direction, δ represents the air gap length,

[0091] S d1 It represents the cross-sectional area of ​​the rotor clamping plate along the length direction, as shown in Figure 4;

[0092] Step J: Calculate the total direct-axis magnetic resistance R d : R d =R0+R1;

[0093] Step K: Calculate the quadrature-axis magnetic resistance R q :

[0094] Where: k2 represents the third correction coefficient, and the calculation result k2 can be corrected by using the electromagnetic field analysis of the simulation software, S q It represents the cross-sectional area of ​​the rotor core in the axial direction along the quadrature axis, as shown in Figure 5;

[0095] Step L: Calculate the motor salient pole ratio K dq :

[0096] Step M: Calculate the motor performance to determine a motor design solution that meets the preset goals.

[0097] There are two methods for calculating motor performance: one is a field-circuit combined design, and the other is a parametric finite element analysis design. Optionally, in step M, one of the following two calculation methods is selected for calculation:

[0098] Method 1: Calculate motor performance using the field-circuit combined method:

[0099] The parameter R d 、R q , K dqThe calculation formula is compiled into the circuit calculation software, and the parameters α1, α2, α3, T si 、T n-c Input the software to calculate the performance indicators of the motor, including motor efficiency and power factor. At the same time, the calculated performance indicators are input into the electromagnetic field calculation software and iterated until convergence to determine the motor design solution that meets the preset goals.

[0100] If you need to further improve the motor efficiency or power factor and other performance, then change α1, α2, α3, T si 、T n-c The parameters are iterated again using the field-combined calculation method to determine the motor design scheme.

[0101] Method 2: Parametric electromagnetic field finite element analysis calculation:

[0102] Or by changing the parameters α1, α2, α3, T si 、T n-c A model was established using ANSYS electromagnetic field calculation software, and different step sizes and ranges were set. The motor efficiency was taken as the goal while taking into account the pulsating torque of the motor for optimization design, and finally a motor design scheme that met the goals was determined.

[0103] In motor design, this application reduces motor losses and torque ripple by adjusting parameters such as the thickness of the magnetic layer, the thickness of the non-magnetic layer, and the pole arc coefficient of the outermost magnetic layer, thereby increasing efficiency and power factor. This design method offers the advantages of accurate calculations, convenience, speed, short calculation cycles, and wide applicability.

[0104] The following describes the design method of the wound radial laminated rotor of the synchronous reluctance motor provided by the present invention using H132-4 as an example. Other designs with different pole numbers and models can be implemented with reference to this method. The rotor laminations are shown in FIG6 . The method includes the following steps:

[0105] 1. Rotor core topology design

[0106] Step 1: Layer the synchronous reluctance motor rotor. The initial number of magnetic conductive layers is 36, and the initial angle of α1 is 90°. As the number of layers increases, the angle of α1 becomes smaller. At this time, the ring formed by winding the magnetic conductive layer and the non-magnetic conductive layer cannot be decomposed into parts with the same number of poles. The initial angle of α3 is 44.85°. The magnetic conductive layer is made of silicon steel, and the thickness of each layer Tsi is 0.7 mm. The non-magnetic conductive layer is 35, and the thickness of each layer Tn-c is 0.3 mm.

[0107] Step 2: Each magnetic conductive layer and non-magnetic conductive layer is in the shape of a sector, with the center being O2, L o1o2 =D2×sinα1 / 2sin(α1+α3)=97.299mm, where D2 is the rotor outer diameter of 135.2mm;

[0108] Step 3: The outer arc radius of the first magnetic layer

[0109] The internal arc radius of the first magnetic permeable layer ri1 = r1 + Tsi = 36.337 mm, where α2 determines the pole arc coefficient of the first magnetic permeable layer. The pole arc coefficient range is 0.65-0.75, then the α2 range is 11.25°-15.75°, the initial pole arc coefficient is 0.7, and α2 is 13.5°;

[0110] The outer arc radius of the second magnetic conductive layer is r2 = ri1 + Tn-c = 36.637 mm, and the inner arc radius of the second magnetic conductive layer is ri2 = r2 + Tsi = 37.337 mm;

[0111] …

[0112] The outer arc radius of the 35th magnetic conductive layer is r35 = 69.637 mm, and the inner arc radius of the 36th magnetic conductive layer is ri35 = 70.337 mm;

[0113] The outer arc radius of the 36th magnetic conductive layer r36 = 70.637 mm, and the inner arc radius of the 36th magnetic conductive layer ri36 = 71.337 mm;

[0114] Step 4: With O2 as the center, draw a circle with r1 and ri1 as the radius. The intersection of the two circles and the rotor is the first magnetic conductive layer. With O2 as the center, draw a circle with r2 and ri2 as the radius. The intersection of the two circles and the rotor is the second magnetic conductive layer. The first non-magnetic conductive layer is between the first and second magnetic conductive layers. ...; With O2 as the center, draw a circle with r36 and ri36 as the radius. The intersection of the two circles and the rotor is the 36th magnetic conductive layer. The 35th non-magnetic conductive layer is between the 35th and 36th magnetic conductive layers.

[0115] Step 5: The middle part between the 36th magnetic conductive layer and the rotating shaft is the rotor bracket, which is used to support the entire rotor core. The material can be high-strength magnetic conductive materials such as iron and steel;

[0116] 2. Calculate the direct-axis magnetic resistance of the motor

[0117] Step 6: Magnetic resistance of the non-magnetic layer in the direct axis direction Where υ0=8×10 5 m·H -1 , Tn-c=0.3mm,n=36,k0 is temporarily set to 1,S av =0.0132m 2 , we can calculate R0=6.36×10 5 H -1 ;

[0118] Step 7: Calculate the direct-axis air gap reluctance between the rotor clamping plate and the rotor core Where T d1 =6.84mm, δ=0.4mm, k1 is temporarily set to 1, S d1 =0.0066m 2 , we can calculate R1=8.78×10 5 H -1 ;

[0119] Step 8: Equivalent total magnetic resistance R of the direct-axis magnetic circuit d =R0+R1=1.51×10 6 H -1 ;

[0120] 3. Calculate the quadrature-axis reluctance of the motor

[0121] Step 9: Calculate the total quadrature-axis reluctance Among them, k2 is temporarily set to 1, S q =0.0045m 2 , we can calculate R q =1.42×10 5 H -1 ;

[0122] 3. Calculation of inductance parameter saliency ratio

[0123] Step 10: Calculate the motor salient pole ratio The finite element simulation result is 10.9, and the two results are similar.

[0124] 4. Calculate motor performance

[0125] Method 1: Calculate motor performance using a combined field-circuit method

[0126] Step 11: R d 、R q , K dq The calculation formulas of parameters such as α1, α2, α3, T si 、T n-c Input parameters such as the motor efficiency and power factor into the software to calculate performance indicators such as the motor efficiency and power factor. At the same time, the calculated relevant parameters are input into the electromagnetic field calculation software and iterated until convergence. The motor design scheme is determined and the motor performance is finally calculated as follows:

[0127] Step 12: To further improve the motor performance, the scheme is optimized with motor efficiency and torque ripple as the goal. In this example, by changing α2, T si 、T n-cAfter the parameters are determined, the field-combined calculation method is used for iteration to finally determine the motor design scheme. At this time, α2 is 13.95°, T si 0.75mm, T n-c is 0.3mm, and the calculation results are as follows:

[0128] Method 2: Parametric electromagnetic field finite element analysis calculation

[0129] Step 13, through α1, α2, α3, T si 、T n-c The model is established in ANSYS electromagnetic field calculation software with parameters such as EMI, and different step sizes and ranges are set to optimize the design with motor efficiency as the goal while taking into account the pulsating torque of the motor.

[0130] Step 14: Optimize Tsi. When Tsi is 0.7mm and 0.85mm respectively, calculate the motor performance. When Tsi changes, the model automatically changes. When Tsi is 0.7mm, the motor efficiency is higher and the torque ripple is smaller. Therefore, Tsi is selected as 0.7mm.

[0131] Step 15. Optimize Tn-c when Tsi is 0.7mm. The Tn-c range is 0.1-0.3mm. The motor performance calculation results are as follows:

[0132] Calculations show that motor efficiency increases with increasing thickness of the non-magnetic layer, while torque ripple increases first and then decreases. Therefore, selecting a Tn-c value of 0.3mm is the optimal solution, where motor efficiency is maximized and torque ripple is minimized.

[0133] Step 16: Optimize the pole arc coefficient, i.e., α2, when Tsi is 0.7 mm and Tn-c is 0.3 mm. The pole arc coefficient range is 0.65 to 0.75, corresponding to an α2 range of 11.25° to 15.75°. The motor performance calculation results are as follows:

[0134] Calculations show that motor efficiency first increases and then decreases as the pole arc coefficient increases, while torque ripple first decreases, then increases, and then decreases again. When the pole arc coefficient is 0.69, the motor efficiency reaches a maximum of 89.89% and the torque ripple reaches a minimum of 5.79%. At this point, α2 is 13.95°. Compared with the first method, the efficiency error is 2.5%, and the torque ripple error is 2.2%, both within reasonable ranges.

[0135] For the H132-4, this design method determined that a Tsi of 0.7 mm, a Tn-c of 0.3 mm, and an α2 of 13.95° maximized motor efficiency and saliency, while minimizing torque ripple. When the motor model changes, these parameters should be redefined. This model and design method are applicable to different types of synchronous reluctance motors.

[0136] In summary, in the motor design, the present invention reduces the motor loss and torque pulsation by adjusting parameters such as the thickness of the magnetic layer, the thickness of the non-magnetic layer, and the pole arc coefficient of the outermost magnetic layer, thereby increasing the efficiency and power factor. This design method has the advantages of accurate calculation, convenience and speed, short calculation cycle, and wide application range. Specifically, the present invention has the following advantages: strong versatility, applicable to synchronous reluctance motors with different pole numbers and different powers; short calculation cycle, only the variables need to be adjusted, and the rotor model will be changed accordingly, without the need to rebuild the model for calculation; by adjusting the thickness of the magnetic layer, the thickness of the non-magnetic layer, and the pole arc coefficient of the outermost magnetic layer, the motor iron loss and torque pulsation are reduced, the efficiency and power factor are increased, and the motor performance is better; high mechanical strength, applicable to medium and high-speed motors, the rotor is connected to the high-strength bracket by high-strength bolts; reduced consumption of waste raw materials, compared with the same model of permanent magnet assisted motors, the silicon steel sheet material loss is smaller.

[0137] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable ordinary technicians in this field to understand the content of the present invention and implement it. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the scope of protection of the present invention.

Claims

1. A synchronous reluctance motor wound radial laminated rotor structure, characterized in that: The rotor structure includes a rotor support, a rotor core, fixing bolts and a pressure block. The rotor core is composed of alternating radial laminates of magnetic conductive layers and non-magnetic conductive layers. The rotor core is fixed to the rotor support by the fixing bolts and the pressure block. The thickness ratio of the magnetic conductive layer to the non-magnetic conductive layer is less than 5:

1. The magnetic conductive layer and the non-magnetic conductive layer of the rotor core are concentric circle structures and are formed into a ring shape by winding the magnetic conductive layer and the non-magnetic conductive layer. The rotor core is divided into the same number of parts as the number of motor poles through a separation process.

2. The wound radial laminated rotor structure of a synchronous reluctance motor according to claim 1, characterized in that: The material of the magnetic conductive layer of the rotor core is one of the following: silicon steel, steel; the material of the non-magnetic conductive layer of the rotor core is one of the following: polyester fiber, epoxy resin, high-strength plastic.

3. A design method for a wound radial laminated rotor structure of a synchronous reluctance motor, characterized in that: The method is used to design a wound radial laminated rotor structure of a synchronous reluctance motor according to any one of claims 1 to 2, and the method comprises: Step A: radially layering the rotor core, wherein the magnetic conductive layers and the non-magnetic conductive layers of the rotor core are alternately stacked, the number of layers of the rotor core is 2n-1, the number of layers of the magnetic conductive layers is n, and the number of layers of the non-magnetic conductive layers is n-1, where n is an integer greater than 10. Step B: Each magnetic conductive layer and non-magnetic conductive layer is in the shape of a ring. The outermost magnetic conductive layer is regarded as the first layer. The magnetic conductive layers are the second layer, the third layer, ..., the nth layer in the direction of the rotor center O1. Each layer is a concentric circle with the center as O2. The distance L between the rotor center O1 and the center O2 is o1o2 : L o1o2 =D2sinα1 / 2sin(α1+α3) Where: D2 represents the outer diameter of the rotor, α1 represents the angle between AO1 and AO2, AO1 is the magnetic pole axis, point A is the intersection of the magnetic pole axis and the outer circle of the rotor, α3 represents the angle between O1B and O1O2, and point B is the intersection of the inner arc of the nth magnetic conductive layer and the outer circle of the rotor; Step C: The magnetic pole arc coefficient k is determined by the angle α2 between O1C and O1O2. Point C is the intersection of the outer arc line of the first magnetic conductive layer and the outer circle of the rotor. k=2(α4-α2) / 2α4=(α4-λ2) / α4 Where: α4 represents the angle between O1A and O1O2, α4＝360 / p / 2； p represents the number of motor poles; Step D: The outer arc radius of the first magnetic conductive layer is The inner arc radius r of the first magnetic permeable layer i1 =r1+T si ; The outer arc radius of the second magnetic permeable layer r2 = r i1 +T n-c , the inner arc radius r of the second magnetic conductive layer i2 =r2+T si ; The outer arc radius of the third magnetic permeable layer r3 = r i2 +T n-c , the inner arc radius r of the third magnetic conductive layer i3 =r3+T si ; And so on. The outer arc radius r of the n-1th magnetic conductive layer n-1 =r i(n-2) +T n-c , the inner arc radius r of the n-1th magnetic conductive layer i(n-1) =r n-1 +T si ; The outer arc radius r of the nth magnetic conductive layer n =r i(n-1) +T n-c , the inner arc radius r of the nth magnetic conductive layer in =r n +T si ; Step E: With O2 as the center, r1, r i1 The intersection of the two circles and the rotor is the first magnetic conductive layer. With O2 as the center, r2, r i2 Draw a diagram with radius, the intersection of the two circles and the rotor is the second magnetic conductive layer, the middle between the first and second magnetic conductive layers is the first non-magnetic conductive layer; and so on; take O2 as the center, and r n 、r in Draw a diagram for the radius. The intersection of the two circles and the rotor is the nth magnetic conductive layer, and the area between the n-1th magnetic conductive layer and the nth magnetic conductive layer is the n-1th non-magnetic conductive layer. Step F: The middle part between the nth magnetic conductive layer and the rotating shaft is the rotor bracket, which is used to support the entire rotor core; Step G, calculating the direct axis magnetic resistance of the motor, wherein the direct axis magnetic resistance of the motor includes the magnetic resistance of the rotor support, the magnetic resistance of the magnetic conductive layer, the magnetic resistance of the non-magnetic conductive layer, the rotor clamping plate and the air gap magnetic resistance; Step H: Calculate the magnetic resistance R0 of the non-magnetic layer in the direct axis direction. Where: k0 represents the first correction coefficient; v0 represents the air magnetic resistivity; S av Indicates the equivalent cross-sectional area of ​​the rotor core lamination along the length direction, S av =(S1+S2+...+S n ) / n, S1 is the area of ​​the arc surface where the midline of the first magnetic layer is located along the length direction, S1=(S o1 +S i1 ) / 2,S o1 is the lengthwise area of ​​the arc surface of the first magnetic permeable layer facing the center O2, S i1 is the area of ​​the arc surface of the first magnetic permeable layer facing away from the center O2 along the length direction, and so on. n The equivalent cross-sectional area of ​​the nth magnetic conductive layer along the length direction, S n =(S on +S in ) / 2,S on is the lengthwise area of ​​the arc surface of the nth magnetic conductive layer facing the center O2, S in is the lengthwise area of ​​the arc surface of the nth magnetic conductive layer facing away from the center O2; Step I: Calculate the direct-axis air gap reluctance R1 between the rotor clamping plate and the rotor core: Where: k1 represents the second correction coefficient, T d1 It represents the distance from the clamping plate to the outer diameter of the rotor in the straight axis direction, δ represents the air gap length, S d1 Indicates the cross-sectional area of ​​the rotor clamp along the length direction; Step J: Calculate the total direct-axis magnetic resistance R d : R d =R0+R1; Step K: Calculate the quadrature-axis magnetic resistance R q : Among them: k2 represents the third correction coefficient, S q It represents the cross-sectional area of ​​the rotor core in the axial direction; Step L: Calculate the motor salient pole ratio K dq : Step M: Calculate the motor performance to determine a motor design solution that meets the preset goals.

4. The method for designing a wound radial laminated rotor structure of a synchronous reluctance motor according to claim 3, characterized in that: The thickness of each magnetic conductive layer is set as T si , T si The value of satisfies one of the following conditions: an integer multiple of 0.35 mm, an integer multiple of 0.5 mm, or the sum of any integer multiple of 0.35 mm and any integer multiple of 0.5 mm; the thickness of each non-magnetic conductive layer is set to T n-c , T n-c The value range is 0.1mm to 0.6mm.

5. The method for designing a wound radial laminated rotor structure of a synchronous reluctance motor according to claim 4, characterized in that: In step M, one of the following two calculation methods is selected for calculation: The parameter R d 、R q , K dq The calculation formula is compiled into the circuit calculation software, and the parameters α1, α2, α3, T si 、T n-c Input the software to calculate the performance indicators of the motor, including motor efficiency and power factor, and input the calculated performance indicators into the electromagnetic field calculation software for iteration until convergence to determine a motor design solution that meets preset goals; or By setting the parameters α1, α2, α3, T si 、T n-c A model was established using ANSYS electromagnetic field calculation software, and different step sizes and ranges were set. The motor efficiency was taken as the goal while taking into account the pulsating torque of the motor for optimization design, and finally a motor design scheme that met the goals was determined.

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