High-torque magnetic field modulation permanent magnet motor design method and electronic equipment

Abstract

The invention relates to the technical field of motor design, and particularly discloses a high-torque magnetic field modulation permanent magnet motor design method and electronic equipment, the high-torque magnetic field modulation permanent magnet motor design method comprises the following steps: determining no-load back electromotive force as a key parameter influencing a motor output torque according to an analytic expression of the motor output torque; a no-load back electromotive force analytic expression is derived and substituted into a motor output torque analytic expression, the output torque is decomposed into a product of a plurality of correlation coefficients, and the internal relation between the coefficients and motor topology design parameters is studied. According to the high-torque magnetic field modulation permanent magnet motor design method and the electronic equipment, the output torque of the motor can be decomposed into the product of the correlation coefficients, the target of analyzing and improving the output torque of the motor is specifically decomposed into the improvement of the correlation coefficients, and the improvement of the output torque of the motor is realized by researching the key coefficient analytic expression influencing the output torque of the motor. And the rule that the key coefficient changes along with design parameters is studied, and finally the motor topology design with the torque performance remarkably improved is formed.

Description

Technical Field

[0001] The invention relates to the technical field of motor design, and in particular to a design method for a high-torque magnetic field modulation permanent magnet motor and an electronic device. Background Art

[0002] The motor model of a traditional permanent magnet motor can be determined by three parameters. At this time, there are very few motor models to choose from, and the optimal model can be screened out by establishing a small number of finite element simulation models. However, the magnetic field modulation permanent magnet motor needs to determine the motor model through five parameters, including the number of phases, the number of slots, the number of permanent magnet pole pairs, the number of winding pole pairs, and the combination of the number of modulation teeth Na on the armature and the number of modulation teeth Nf on the fault-tolerant teeth. This leads to a significant increase in the number of models of magnetic field modulation permanent magnet motors, and the design process is more complicated and difficult. It is necessary to systematically analyze the impact of the main design parameters on the torque performance and explore the corresponding high-torque design methods. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to at least some extent. To this end, the purpose of the present invention is to provide a high torque magnetic field modulation permanent magnet motor design method and electronic equipment to design a magnetic field modulation permanent magnet motor with better torque performance.

[0004] To achieve the above object, a first embodiment of the present invention provides a method for designing a high torque magnetic field modulation permanent magnet motor, the method comprising:

[0005] According to the analytical formula of the motor output torque, the no-load back electromotive force is determined to be the key parameter affecting the motor output torque;

[0006] Derive the analytical formula of no-load back EMF, substitute it into the analytical formula of motor output torque, decompose the output torque into the product of multiple related coefficients, and study the intrinsic relationship between these coefficients and motor topology design parameters;

[0007] The influence of motor topology design parameters on the above torque coefficients is studied in turn, a design method to improve the torque coefficient is proposed, and simulation verification is performed on the motor model;

[0008] Based on the above design methods, the design method of high torque motor is summarized;

[0009] According to the above high torque design method, the topology design of the high torque magnetic field modulation permanent magnet motor is completed.

[0010] As an embodiment of the present invention, without considering magnetic field saturation, the motor output torque is determined by the no-load back electromotive force and the input current, and its calculation expression is as follows:

[0011]

[0012] Where, m represents the number of motor phases, I n Represents the input current amplitude, E A Represents the no-load back EMF amplitude, ω r is the rotor angular velocity of the motor.

[0013] As an embodiment of the present invention, the analytical expression of the no-load back electromotive force is as follows:

[0014]

[0015] Among them, ψ A is the permanent magnetic flux linkage;

[0016] ψ A The analytical expression of is as follows:

[0017] ψ A =n s ∫B(θ s ,t)dθ s

[0018] Among them, n s is the number of turns per phase of the motor winding, θ s is the mechanical angle of the motor stator, and B is the air gap flux density of the motor;

[0019] The analytical expression of B is as follows:

[0020] B(θ s ,t)=F(θ s ,t)×Λ(θ s )

[0021] Where F is the permanent magnet magnetomotive force, Λ is the air gap permeance;

[0022] The analytical expressions of F and Λ are as follows:

[0023]

[0024] Among them, P r is the number of permanent magnet poles of the motor, Z f is the number of motor modulation teeth, F i is the harmonic amplitude of the i-th order magnetomotive force, Λ j is the jth harmonic amplitude of the air gap permeability, Λ 0 is the DC component of the air gap permeability.

[0025] As an embodiment of the present invention, the analytical formula for deriving the no-load back electromotive force, substituting it into the analytical formula for the motor output torque includes:

[0026] Let F, Λ, B, ψ A and E ASubstitute the analytical expression of into the analytical expression of the motor output torque to obtain the following formula:

[0027]

[0028] Among them, K 0 is defined as the structural coefficient, K v Defined as the amplification factor of the Vth harmonic, B v is defined as the Vth harmonic amplitude, K av is defined as the angular coefficient;

[0029] V and nj are defined as follows:

[0030]

[0031] K 0 , K v , B v and K av The specific expression is as follows:

[0032]

[0033] Among them, l stk Represents the axial length of the motor, R s represents the motor air gap radius, V represents the motor magnetic field harmonic order, N a represents the number of modulation poles on the armature teeth, t sp represents the modulation tooth arc, w s Represents the modulated inter-tooth arc.

[0034] As an embodiment of the present invention, the influence of the motor topology design parameters on the above-mentioned torque coefficients is studied in sequence, and a design method for improving the torque coefficient is proposed, which includes:

[0035] Analyze the above motor output torque analytical formula to get the influence of K av The topological structure parameter is the combination of the number of modulation poles on the armature teeth and the fault-tolerant teeth, that is, N a +N f The relationship between this combination and the motor tooth design can be expressed as:

[0036]

[0037] Among them, Z s is the number of slots of the motor;

[0038] Impact K v The topological structure parameter is the number of permanent magnet pole pairs P of the motor. r , winding pole pair number P s , the number of phases m and the number of slots Z s ;

[0039] Among them, P r , P s , m and Z s The relationship between can be expressed as:

[0040] P r +P s =Z f

[0041] Z s =i×m,i=2.4.6.8.....

[0042] Impact B v The topological structure parameter is the number of permanent magnet pole pairs P of the motor. r And the gear structure design of the motor.

[0043] As an embodiment of the present invention, the design method of the motor high torque is:

[0044] When designing the modulation pole combination N on the armature teeth and the fault-tolerant teeth a +N f When it is n+1, the angle coefficients of the motor harmonics are combined to form the largest K av , at this time the motor torque is maximum.

[0045] As an embodiment of the present invention, a method for increasing motor torque includes:

[0046] For a magnetic field modulated permanent magnet motor with the same air gap radius, there is an optimal number of permanent magnet pole pairs P that maximizes the torque. ro , and the larger the air gap radius, the larger the ro The larger the value, the greater the number of permanent magnet pole pairs P of the motor. r The closer the design is to P ro , the greater the motor torque.

[0047] As an embodiment of the present invention, a method for increasing motor torque includes:

[0048] Reduce the number of phases m and slots Z of the motor s Can effectively improve the torque of the motor;

[0049] The number of winding pole pairs of the motor P s Design to meet P s <P s / 2, the motor torque is maximized.

[0050] As an embodiment of the present invention, the topology design of the high torque magnetic field modulation permanent magnet motor includes:

[0051] Design a topology design of a field modulation permanent magnet motor with 5 phases, 10 slots, 35 modulation poles, 32 permanent magnet pole pairs, 3 winding pole pairs, and 6+1 modulation tooth combination.

[0052] To achieve the above objectives, a second aspect of the present invention proposes an electronic device, comprising a memory, a processor and a computer program stored on the memory. When the computer program is executed by the processor, the above-mentioned high-torque magnetic field modulation permanent magnet motor design method is implemented.

[0053] The high-torque magnetic field modulated permanent magnet motor design method and electronic device of the embodiments of the present invention can decompose the motor output torque into the product of four coefficients: structural coefficient, angular coefficient, amplification coefficient and magnetic field harmonics, and specifically decompose the goal of analyzing and improving the motor output torque into improving the above four key coefficients, thereby simplifying the analysis difficulty; and by studying the analytical expressions of the four key coefficients that affect the motor output torque, analyzing the intrinsic connection between the main topological design parameters of the motor and the key coefficients, studying the law of change of the key coefficients with the design parameters, analyzing and summarizing the design method of the motor with high output torque, and finally forming a motor topology design with significantly improved torque performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 It is a flow chart of a method for designing a high torque magnetic field modulation permanent magnet motor according to an embodiment of the present invention;

[0055] Figure 2 It is a parameter definition diagram of a motor unit module in a magnetic field modulation permanent magnet motor according to an embodiment of the present invention;

[0056] Figure 3 The invention discloses the influence of the combination of the modulating poles on the stator armature teeth and the fault-tolerant teeth on the low-order working harmonic angular coefficients according to an embodiment of the invention;

[0057] Figure 4 The influence of the modulation pole combination on the stator armature teeth and the fault-tolerant teeth on the no-load back electromotive force amplitude of the motor in one embodiment of the present invention;

[0058] Figure 5 The invention discloses an influence rule of the combination of the modulated poles on the stator armature teeth and the fault-tolerant teeth on the output torque of the motor;

[0059] Figure 6 The influence of the number of pole pairs of the motor winding on the no-load back electromotive force amplitude in one embodiment of the present invention is as follows;

[0060] Figure 7 The influence of the number of pole pairs of the motor winding on the output torque according to an embodiment of the present invention is as follows;

[0061] Figure 8The influence of the number of permanent magnet pole pairs on the harmonic amplification factor of the motor and the amplitude of the permanent magnet magnetomotive force in one embodiment of the present invention;

[0062] Fig. 9 is the trend of the output torque of the ten-slot magnetic field modulation permanent magnet motor according to an embodiment of the present invention as the number of permanent magnet pole pairs changes;

[0063] Fig.10 The output torque of a magnetic field modulated permanent magnet motor with different air gap radii according to an embodiment of the present invention varies with the number of permanent magnet pole pairs;

[0064] Fig.11 The law that the no-load back electromotive force amplitude of the magnetic field modulation permanent magnet motor according to an embodiment of the present invention is affected by the number of motor slots and the number of phases;

[0065] Fig.12 It is a topological structure diagram of a magnetic field modulation permanent magnet motor designed by a high output torque design method according to an embodiment of the present invention;

[0066] Fig.13 is a comparison diagram of the air gap flux density harmonic amplitudes of a magnetic field modulation permanent magnet motor using a high output torque design method of the present invention and a motor using a traditional design according to an embodiment of the present invention;

[0067] Fig.14 is a comparison diagram of the contribution of each harmonic of the air gap flux density to the output torque of a magnetic field modulation permanent magnet motor using the high output torque design method of the present invention and a motor using a traditional design in accordance with an embodiment of the present invention;

[0068] Fig.15 is a comparison diagram of average output torque and torque ripple of a magnetic field modulation permanent magnet motor using a high output torque design method of the present invention and a motor using a traditional design in one embodiment of the present invention;

[0069] Fig.16 It is a schematic structural diagram of an electronic device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0070] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0071] The following describes a high torque magnetic field modulation permanent magnet motor design method and an electronic device according to an embodiment of the present invention with reference to the accompanying drawings.

[0072] Figure 1 It is a flow chart of a method for designing a high torque magnetic field modulation permanent magnet motor according to an embodiment of the present invention.

[0073] like Figure 1 As shown in FIG. 1 , the design method of a high torque magnetic field modulation permanent magnet motor includes:

[0074] S1. According to the analytical expression of the motor output torque, it is determined that the no-load back electromotive force is the key parameter affecting the motor output torque.

[0075] As an embodiment of the present invention, without considering magnetic field saturation, the motor output torque is determined by the no-load back electromotive force and the input current, and its calculation expression is as follows:

[0076]

[0077] Where, m represents the number of motor phases, I n Represents the input current amplitude, E A Represents the no-load back EMF amplitude, ω r is the rotor angular velocity of the motor.

[0078] S2. Derive the analytical expression of no-load back EMF, substitute it into the analytical expression of motor output torque, decompose the output torque into the product of multiple related coefficients, and study the intrinsic relationship between these coefficients and motor topology design parameters.

[0079] As an embodiment of the present invention, the analytical expression of the no-load back electromotive force is as follows:

[0080]

[0081] Among them, ψ A is the permanent magnetic flux linkage;

[0082] ψ A The analytical expression of is as follows:

[0083] ψ A =n s ∫B(θ s ,t)dθ s

[0084] Among them, n s is the number of turns per phase of the motor winding, θ s is the mechanical angle of the motor stator, and B is the air gap flux density of the motor;

[0085] The analytical expression of B is as follows:

[0086] B(θ s ,t)=F(θ s ,t)×Λ(θ s )

[0087] Where F is the permanent magnet magnetomotive force, Λ is the air gap permeance;

[0088] The analytical expressions of F and Λ are as follows:

[0089]

[0090] Among them, P r is the number of permanent magnet poles of the motor, Z f is the number of motor modulation teeth, F i is the harmonic amplitude of the i-th order magnetomotive force, Λ j is the jth harmonic amplitude of the air gap permeability, Λ 0 is the DC component of the air gap permeability.

[0091] Furthermore, F, Λ, B, ψ A and E A The analytical expression of is brought into the analytical expression of the motor output torque, thereby decomposing the output torque into the product of multiple correlation coefficients, and the following formula is obtained:

[0092]

[0093] Among them, K 0 is defined as the structural coefficient, K v Defined as the amplification factor of the Vth harmonic, B v is defined as the Vth harmonic amplitude, K av is defined as the angular coefficient;

[0094] V and nj are defined as follows:

[0095]

[0096]

[0097] K 0 , K v , B v and K av The specific expression is as follows:

[0098]

[0099] Among them, l stk Represents the axial length of the motor, R s represents the motor air gap radius, V represents the motor magnetic field harmonic order, N a represents the number of modulation poles on the armature teeth, t sp represents the modulation tooth arc, w s Represents the modulated inter-tooth arc.

[0100] As an example, the parameter definition of a motor unit module in a field modulated permanent magnet motor is as follows: Figure 2 shown.

[0101] S3. Study the influence of motor topology design parameters on the above torque coefficients in turn, propose a design method to improve the torque coefficient, and perform simulation verification on the motor model.

[0102] As an embodiment of the present invention, the above motor output torque analytical formula is analyzed to obtain the factors affecting K av The topological structure parameter is the combination of the number of modulation poles on the armature teeth and the fault-tolerant teeth, that is, N a +N f The relationship between this combination and the motor tooth design can be expressed as:

[0103]

[0104] Among them, Z s is the number of slots of the motor;

[0105] Impact K v The topological structure parameter is the number of permanent magnet pole pairs P of the motor. r , winding pole pair number P s , the number of phases m and the number of slots Z s ;

[0106] Among them, P r , P s , m and Z s The relationship between can be expressed as:

[0107] P r +P s =Z f

[0108] Z s =i×m,i=2.4.6.8.....

[0109] Impact B v The topological structure parameter is the number of permanent magnet pole pairs P of the motor. r And the gear structure design of the motor.

[0110] S4. Based on the above design method, the design method of high torque motor is summarized;

[0111] S5. According to the above high torque design method, the topology design of the high torque magnetic field modulation permanent magnet motor is completed.

[0112] Further analysis of the above step S3 is conducted to analyze the influence of motor topology design parameters on different torque coefficients:

[0113] As an embodiment of the present invention, Figure 2 Parameter definition of a motor unit module of a magnetic field modulation permanent magnet motor and the angle coefficient K avFrom the analytical formula, it can be concluded that the combination of the number of modulation poles on the armature teeth and the fault-tolerant teeth will significantly affect the angular coefficient of each harmonic. Here, taking the 5-phase, 10-slot and 5-phase, 20-slot motors as examples, the angular coefficient is further decomposed:

[0114]

[0115] In the formula, i is a positive integer, a is the ratio of the angle at which the armature tooth receives the magnetic flux to the angle corresponding to each two slots, and its value is less than 1. The expression is as follows:

[0116]

[0117] Breaking it down further:

[0118]

[0119] Combining from above Figure 3 The influence of the modulation pole combination on the stator armature teeth and the fault-tolerant teeth on the low-order working harmonic angular coefficient can be seen. For the 1st working harmonic, the larger the a value, the larger the angular coefficient K a1 The larger the value, the larger the s For subharmonics, a takes the maximum value when It does not necessarily take the maximum value. However, based on the above analysis and combined Figure 4 The influence of the modulation pole combination on the stator armature teeth and the fault-tolerant teeth on the no-load back electromotive force amplitude of the motor and Figure 5 The influence of the modulation pole combination on the stator armature teeth and the fault-tolerant teeth on the motor output torque can be found that relative to P s The amplification factor of the first harmonic is greater, so the first harmonic K a1 The weight of the value is higher, so when a takes the maximum value, that is, N a With N f When the combination of is n+1, the motor can obtain the optimal no-load back electromotive force amplitude and output torque. That is, when the modulation pole combination N on the armature teeth and the fault-tolerant teeth is designed a +N f When it is n+1, the angle coefficients of the motor harmonics are combined to form the largest K av , at this time the motor torque is maximum.

[0120] As an embodiment of the present invention, according to the motor harmonic amplification factor K v The analytical expression can be used to analyze the relationship between the number of motor winding poles and K v The inner connection:

[0121]

[0122] Analyze the above formula Figure 6The influence of the number of motor winding pole pairs on the no-load back electromotive force amplitude and Figure 7 The influence of the number of motor winding pole pairs on the output torque shows that a smaller number of winding pole pairs is beneficial to improving the amplification factor of the motor harmonics and thus improving the no-load back-electromotive force amplitude and output torque of the motor.

[0123] As an embodiment of the present invention, according to the motor harmonic amplification factor K v And harmonic magnetic flux density B v The analytical expression of can be used to analyze the intrinsic relationship between the permanent magnet pole and it. Figure 8 The influence of the number of permanent magnet pole pairs on the harmonic amplification factor of the motor and the amplitude of the permanent magnet magnetomotive force can be found. r K v With B v The value of has the opposite effect. Fig. 9 The trend of the output torque of the magnetic field modulated permanent magnet motor changing with the number of permanent magnet pole pairs indicates that there is a fixed optimal number of permanent magnet pole pairs that can enable the motor to obtain the highest output torque. Fig.10 This figure shows the trend of the output torque of the magnetic field modulation permanent magnet motor with different air gap radii changing with the number of permanent magnet pole pairs. It can be found from the figure that the smaller the motor air gap radius, the smaller the optimal specified number of permanent magnet pole pairs.

[0124] As an embodiment of the present invention, according to the motor harmonic amplification factor K v The analytical expression of the motor slot number and phase number can be used to analyze the internal relationship between the motor slot number and phase number. Fig.11 The law that the amplitude of the no-load back-EMF of the magnetic field modulated permanent magnet motor is affected by the number of slots and phases of the motor shows that designing the number of slots and phases lower is beneficial to improving the no-load back-EMF and output torque of the motor.

[0125] As an embodiment of the present invention, a method for increasing motor torque includes:

[0126] For a magnetic field modulated permanent magnet motor with the same air gap radius, there is an optimal number of permanent magnet pole pairs P that maximizes the torque. ro , and the larger the air gap radius, the larger the ro The larger the value, the greater the number of permanent magnet pole pairs P of the motor. r The closer the design is to P ro , the greater the motor torque.

[0127] As an embodiment of the present invention, a method for increasing motor torque includes:

[0128] Reduce the number of phases m and slots Z of the motor s Can effectively improve the torque of the motor;

[0129] The number of winding pole pairs of the motor P sDesign to meet P s <P s / 2, the motor torque is maximized.

[0130] Further analysis of the above S4 step, based on the analysis of the influence of the key topological design parameters of the magnetic field modulation permanent magnet motor on the torque coefficient, determined the high torque design method of the motor as follows: design a relatively small number of slots and phases; design a small number of winding pole pairs; design the modulation pole combination on the armature teeth and the fault-tolerant teeth to be n+1; design the number of permanent magnet pole pairs to be close to the fixed optimal pole pair number.

[0131] The above step S5 is further analyzed, and the high torque design method of magnetic field modulation permanent magnet motor is adopted to design the motor topology, analyze the mechanism of torque improvement, and compare the torque improvement amplitude.

[0132] As an embodiment of the present invention, the topology design of the high torque magnetic field modulation permanent magnet motor includes:

[0133] S51, Fig.12 It is a topological structure diagram of a magnetic field modulation permanent magnet motor designed using a high output torque design method. Fig.12 In the figure, the stator laminated core is D1, the rotor laminated core is D2, the permanent magnet is D3, the modulation pole is D4, the armature winding is D5, the armature tooth is D6, and the fault-tolerant tooth is D7. From the figure, we can see that the motor adopts the Na-Nf n+1 design; the permanent magnet pole pair number is designed to be 32, which is close to the fixed optimal pole pair number of 30; the winding pole pair number is designed to be a smaller 3 pairs of poles; the slot number is designed to be 10 slots; and the phase number is 5 phases.

[0134] S52, Fig.13 It is a comparison of the air gap magnetic flux harmonics of the magnetic field modulation permanent magnet motor designed by the high output torque design method of the present invention and the motor designed by the traditional method. From the figure, it can be seen that the harmonic content in the air gap magnetic field of the motor of the present invention is richer and the order of the low-order harmonics is lower.

[0135] S53, Fig.14 The figure shows the contribution of the air gap magnetic flux harmonics to the torque of the magnetic field modulation permanent magnet motor designed by the high output torque design method of the present invention and the motor designed by the traditional method. It can be seen from the figure that the contribution of the air gap magnetic flux harmonics to the torque of the motor of the present invention is greater.

[0136] S54, Fig.15 The figure shows the average output torque and torque pulsation of the magnetic field modulation permanent magnet motor designed by the high output torque design method of the present invention and the motor designed by the traditional design. It can be seen from the figure that when the input current amplitude is 4A, the output torque of the motor of the present invention is 17.7Nm, which is significantly improved compared with the 7.1Nm of the motor designed by the traditional design. And the torque pulsation is relatively low.

[0137] Corresponding to the above method, the present invention also provides an electronic device.

[0138] like Fig.16 The figure shows a schematic diagram of the structure of an electronic device in the present invention, where the electronic device 200 includes: a processor 201 and a memory 203. The processor 201 and the memory 203 are connected, such as through a bus 202. Optionally, the electronic device 200 may further include a transceiver 204. It should be noted that in actual applications, the transceiver 204 is not limited to one, and the structure of the electronic device 200 does not constitute a limitation on the embodiments of the present invention.

[0139] The processor 201 may be a CPU (Central Processing Unit), a general-purpose processor, a DSP (Digital Signal Processor), an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array) or other programmable logic devices, transistor logic devices, hardware components or any combination thereof. It may implement or execute various exemplary logic blocks, modules and circuits described in conjunction with the disclosure of the present invention. The processor 201 may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a DSP and a microprocessor, etc.

[0140] The bus 202 may include a path to transmit information between the above components. The bus 202 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus. The bus 202 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 2 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0141] The memory 203 is used to store a computer program corresponding to the high torque magnetic field modulation permanent magnet motor design method of the above embodiment of the present invention, and the computer program is controlled and executed by the processor 201. The processor 201 is used to execute the computer program stored in the memory 203 to implement the content shown in the above method embodiment.

[0142] The electronic device 200 includes, but is not limited to, mobile terminals such as laptop computers, PADs (tablet computers), and fixed terminals such as desktop computers. Figure 2 The electronic device 200 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0143] The electronic device 200 of the embodiment of the present invention can decompose the motor output torque into the product of four coefficients: structural coefficient, angular coefficient, amplification coefficient and magnetic field harmonics, and specifically decompose the analysis of improving the motor output torque into improving the above four key coefficients, thereby simplifying the difficulty of analysis; and by studying the analytical expressions of the four key coefficients that affect the motor output torque, analyzing the intrinsic relationship between the main motor topology design parameters and the key coefficients, studying the law of changes of the key coefficients with the design parameters, analyzing and summarizing the design method of the motor high output torque, and finally forming a motor topology design with significantly improved torque performance. The embodiment of the present invention systematically analyzes the influence of the motor topology structure parameters on the motor output torque, studies the design method of the high torque motor, and thus designs a motor model with greatly improved torque performance.

[0144] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or otherwise processing in a suitable manner if necessary, and then stored in a computer memory.

[0145] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0146] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0147] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0148] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A design method for a high torque magnetic field modulation permanent magnet motor, characterized in that: The method comprises: According to the analytical expression of the motor output torque, the no-load back electromotive force is determined to be the key parameter affecting the motor output torque; Derive the analytical formula of no-load back EMF, substitute it into the analytical formula of motor output torque, decompose the output torque into the product of multiple related coefficients, and study the intrinsic relationship between these coefficients and motor topology design parameters; The influence of motor topology design parameters on the above torque coefficients is studied in turn, a design method to improve the torque coefficient is proposed, and simulation verification is performed on the motor model; Based on the above design methods, the design method of high torque motor is summarized; According to the above high torque design method, the topology design of the high torque magnetic field modulation permanent magnet motor is completed.

2. The high torque magnetic field modulation permanent magnet motor design method according to claim 1 is characterized in that: Without considering magnetic field saturation, the motor output torque is determined by the no-load back electromotive force and the input current, and its calculation expression is as follows: Where, m represents the number of motor phases, I n Represents the input current amplitude, E A Represents the no-load back EMF amplitude, ω r is the rotor angular velocity of the motor.

3. The high torque magnetic field modulation permanent magnet motor design method according to claim 2 is characterized in that: The analytical expression of the no-load back electromotive force is as follows: Among them, ψ A is the permanent magnetic flux linkage; ψ A The analytical expression of is as follows: ψ A =n s ∫B(θ s ,t)dθ s Among them, n s is the number of turns per phase of the motor winding, θ s is the mechanical angle of the motor stator, and B is the air gap flux density of the motor; The analytical expression of B is as follows: B(θ s ,t)=F(θ s ,t)×Λ(θ s ) Where F is the permanent magnet magnetomotive force, Λ is the air gap permeance; The analytical expressions of F and Λ are as follows: Among them, P r is the number of permanent magnet poles of the motor, Z f is the number of motor modulation teeth, F i is the harmonic amplitude of the i-th order magnetomotive force, Λ j is the jth harmonic amplitude of the air gap permeability, and Λ0 is the DC component of the air gap permeability.

4. The high torque magnetic field modulation permanent magnet motor design method according to claim 3 is characterized in that: The analytical formula for deriving the no-load back electromotive force, when substituted into the analytical formula for the motor output torque, includes: Let F, Λ, B, ψ A and E A Substitute the analytical expression of into the analytical expression of the motor output torque to obtain the following formula: Among them, K0 is defined as the structural coefficient, K v Defined as the amplification factor of the Vth harmonic, B v is defined as the Vth harmonic amplitude, K av is defined as the angular coefficient; V and nj are defined as follows: K0, K v , B v and K av The specific expression is as follows: Among them, l stk Represents the axial length of the motor, R s represents the motor air gap radius, V represents the motor magnetic field harmonic order, N a represents the number of modulation poles on the armature teeth, t sp represents the modulation tooth arc, w s Represents the modulated inter-tooth arc.

5. The high torque magnetic field modulation permanent magnet motor design method according to claim 4, characterized in that: The effects of the motor topology design parameters on the above torque coefficients are studied in turn, and a design method for improving the torque coefficient is proposed, including: Analyze the above motor output torque analytical formula to get the influence of K av The topological structure parameter is the combination of the number of modulation poles on the armature teeth and the fault-tolerant teeth, that is, N a +N f The relationship between this combination and the motor tooth design can be expressed as: Among them, Z s is the number of slots of the motor; Impact K v The topological structure parameter is the number of permanent magnet pole pairs P of the motor. r , winding pole pair number P s , the number of phases m and the number of slots Z s ; Among them, P r , P s , m and Z s The relationship between can be expressed as: P r +P s =Z f Z s =i×m,i=2.4.6.8..... Impact B v The topological structure parameter is the number of permanent magnet pole pairs P of the motor. r And the gear structure design of the motor.

6. The high torque magnetic field modulation permanent magnet motor design method according to claim 5, characterized in that: The design method of the motor high torque is: When designing the modulation pole combination N on the armature teeth and the fault-tolerant teeth a +N f When it is n+1, the angle coefficients of the motor harmonics are combined to form the largest K av , at this time the motor torque is maximum.

7. The high torque magnetic field modulation permanent magnet motor design method according to claim 6, characterized in that: Methods for increasing motor torque include: For a magnetic field modulated permanent magnet motor with the same air gap radius, there is an optimal number of permanent magnet pole pairs P that maximizes the torque. ro , and the larger the air gap radius, the larger the ro The larger the value, the greater the number of permanent magnet pole pairs P of the motor. r The closer the design is to P ro , the greater the motor torque.

8. The high torque magnetic field modulation permanent magnet motor design method according to claim 6, characterized in that: Methods for increasing motor torque include: Reduce the number of phases m and slots Z of the motor s Can effectively improve the torque of the motor; The number of winding pole pairs of the motor P s Design to meet P s <P s / 2, the motor torque is maximized.

9. The high torque magnetic field modulation permanent magnet motor design method according to claim 1, characterized in that: The topology design of the high torque magnetic field modulation permanent magnet motor includes: Design a topology design of a field modulation permanent magnet motor with 5 phases, 10 slots, 35 modulation poles, 32 permanent magnet pole pairs, 3 winding pole pairs, and 6+1 modulation tooth combination.

10. An electronic device, characterized in that: The invention comprises a memory, a processor and a computer program stored in the memory. When the computer program is executed by the processor, the high torque magnetic field modulation permanent magnet motor design method as described in any one of claims 1 to 9 is implemented.

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