Abstract:
A magnetic field-modulated transverse flux multiphase permanent magnet motor consisting of a stator and a rotor. A number m of phase armature units are arranged in a row along the axial direction within a motor housing ( 1 ); each successive phase armature unit is offset in the circumferential direction by an electrical angle of 360°/m; the armature coil ( 2 ) is embedded within an annular cavity between the first to the third stator iron core tooth segments ( 3, 4, 5 ); the external circumferential surfaces of the first and the third rotor iron core tooth segments ( 6, 8 ) are respectively grooved in the axial direction with k/2 permanent magnet slots; the rotor permanent magnet slot on the first rotor iron core tooth segment ( 6 ) is axially offset from the rotor permanent magnet slot on the third rotor iron core tooth segment ( 8 ) by one-half the rotor tooth pitch; the direction of magnetization of the rotor permanent magnets ( 9 ) is identical. The present motor features high reliability and high security, high fault tolerance, structural simplicity, low costs, high torque density, good dynamic characteristics and ease of modularization.

Description:
CROSS REFERENCE OF RELATED APPLICATION 
     This is a national phase national application of an international patent application number PCT/CN2012/078088 with a filing date of Jul. 3, 2012, which claimed priority of a foreign application number 201110390301.6 with a filing date of Nov. 30, 2011 in China. The contents of these specifications, including any intervening amendments thereto, are incorporated herein by reference. 
     BACKGROUND OF THE PRESENT INVENTION 
     1. Field of Invention 
     The present invention relates to a transverse flux multiphase permanent magnet motor. 
     2. Description of Related Arts 
     Referring to  FIG. 1  of the drawings, a schematic diagram of a conventional multiphase permanent magnet synchronous motor is illustrated. The conventional multiphase permanent magnet synchronous motor usually comprises a stator and a plurality of armature units distributed along the stator. Each armature units comprises a winding consisting of a large number of conductors. For this type of conventional armature units, the end portions of the armature units have extended lengths and may intersect with or overlap on each other. This construction causes great copper loss, the need of complicated insulation structure for each armature unit, and high manufacturing cost. Moreover, each armature unit may have magnetic coupling with other armature units, and this phenomena causes mutual inductance between the affected armature units, thus increasing the difficulty in controlling and ensuring the precision of the multiphase currents. On the other hand, this phenomena also causes long flux path and substantial stator iron loss for each armature unit. All these disadvantages substantially limit any significant increase or improvement in an overall efficiency of the conventional multiphase permanent magnet synchronous motor. At the same time, since the conventional multiphase permanent magnet synchronous motor utilizes the electromagnetic torque developed by the induction between the magnetic field generated by the permanent magnet rotor and the multiphase currents flowing through the stator, the torque density of conventional multiphase permanent magnet synchronous motor is relatively low, and this limitation in torque density substantially limits the range of applications of conventional multiphase permanent magnet synchronous motors. 
     SUMMARY OF THE PRESENT INVENTION 
     Technical Problems 
     In order to resolve the problems of low reliability, high energy loss, low torque density, and complicated structure of conventional multiphase permanent magnet synchronous motor, the present invention provides a magnetic field modulated transverse flux multiphase permanent magnet motor. 
     Technical Solutions 
     In a first aspect of the present invention, it provides a magnetic field modulated transverse flux multiphase permanent magnet motor, comprising a stator and a rotor, wherein the stator and the rotor are spaced apart from each other to form an air gap therebetween, the stator comprising a stator casing and m armature units, where m is a number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3, each of the armature units comprising an armature core and an armature winding, wherein each of the armature cores comprises n stator core teeth, wherein n is an integer, each of the stator core teeth having a first stator teeth section, a second stator teeth section, and a third stator teeth section, wherein each of the first stator teeth section, the second stator teeth section, and the third stator teeth section has an annular structure and has a same external diameter, the second stator teeth section being provided between the first stator teeth section and the third stator teeth section, wherein an internal diameter of the second stator teeth section is greater than that of the first stator teeth section and the third stator teeth section, while an internal diameter of the first stator teeth section is the same as that of the third stator teeth section, the first stator teeth section, the second stator teeth section, and the third stator teeth section being eccentrically arranged to share a common central longitudinal axis, the armature winding being embedded in a space formed between the first stator teeth section, the second stator teeth section and the third stator teeth section, the stator casing being tubular in structure, and having a plurality of casing slots forming on an inner surface thereof, wherein the casing slots are longitudinally formed along a longitudinal direction of the stator casing, wherein a number of casing slots formed on the stator casing is equal to a number of the stator core teeth, the stator core teeth being engaged with the casing slots respectively from a circumferential direction of the stator casing, wherein a transverse depth of each of the stator core teeth is greater than or equal to a transverse depth of the corresponding casing slot of the stator casing, the armature units being sequentially arranged along a longitudinal direction of the stator casing, wherein each of the armature units are distributed along the circumferential direction of the stator casing in such a manner that each of the armature units has an electrical angle of 360°/m, the rotor comprising a rotor core and k rotor permanent magnets, where k is an even number, wherein the rotor core has a first rotor core section, a second rotor core section, and a third rotor core section, each of the first rotor core section, the second rotor core section and the third rotor core section being annular in structure, and having an identical internal diameter, wherein the second rotor core section is positioned between the first rotor core section and the third rotor core section, wherein an external diameter of the second rotor core section is smaller than an external diameter of the first rotor core section and an external diameter of the third rotor core section, while the external diameter of the first rotor core section is identical to that of the third rotor core section, the first rotor core section, the second rotor core section and the third rotor core section being eccentrically arranged to share a common central longitudinal axis, wherein a thickness of the first rotor core section is identical to that of the first stator teeth section, while a thickness of the second rotor core section is identical to that of the second stator teeth section, and a thickness of the third rotor core section is identical to that of the third stator teeth section, wherein for each of the armature units, the first rotor core section, the second rotor core section, and the third rotor core section of the rotor core are aligned with the corresponding first stator teeth section, the fourth stator teeth section, and the third stator teeth section respectively, each of the first rotor core section and the third rotor core section further having k/2 magnet receiving slots longitudinally forming on an outer circumferential surface of the first rotor core section and the third rotor core section, in such a manner that the k/2 magnet receiving slots of the first rotor core section are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section are evenly distributed along a circumferential direction thereof, wherein with respect to the longitudinal direction of the rotor, the magnet receiving slots of the first rotor core section are arranged not to be aligned with the magnet receiving slots of the third rotor core section, the rotor permanent magnets being received in the magnet receiving slots respectively, wherein each of the rotor permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the rotor permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the rotor permanent magnets with respect to the rotor is identical, wherein each of the rotor permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator. 
     In a second aspect of the present invention, it provides a magnetic field modulated transverse flux multiphase permanent magnet motor, comprising a stator and a rotor, wherein the stator and the rotor are spaced apart from each other to form an air gap therebetween, the stator comprising a stator casing and m armature units, where m is a number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3, the stator casing being tubular in structure, each of the armature units comprising an armature core and an armature winding, wherein each of the armature cores has a first armature core section, a second armature core section, and a third armature core section, each of the first armature core section, the second armature core section, and the third armature core section having an annular structure and an identical external diameter, the second armature core section being positioned between the first armature core section and the third armature core section, wherein an internal diameter of the second armature core section is greater than that of the first armature core section and the third armature core section, while an internal diameter of the first armature core section is identical to that of the third armature core section, the first armature core section, the second armature core section, and the third armature core section being eccentrically arranged to share the a common central longitudinal axis, and being sequentially and securely supported in the core casing along a longitudinal direction thereof, the first armature core section and the third armature core section having a plurality of stator core slots formed on an inner circumferential surface of the first armature core section and the third armature core section, wherein a number of the stator core slots forming on the first armature core section is equal to a number of the stator core slots forming on the third armature core section, wherein the stator core slots of the first armature core section are evenly distributed along a circumferential direction thereof, while the stator core slots of the third armature core section are evenly distributed along a circumferential direction thereof, wherein the stator core slots forming on the first armature core section are symmetrically distributed with respect to the stator core slots forming on the third armature core section, the armature winding being embedded in a space formed between the first armature core section, the second armature core section, and the third armature core section, wherein the m armature units are sequentially and securely supported in the core casing along a longitudinal direction thereof, each of the armature units being distributed along a circumferential direction of the stator casing in such a manner that each of the armature units has an electrical angle of 360°/m, the rotor comprising a rotor core and k rotor permanent magnets, where k is an even number, the rotor core having a first rotor core section, a second rotor core section, and a third rotor core section, each of the first rotor core section, the second rotor core section and the third rotor core section being annular in structure, and having an identical internal diameter, wherein the second rotor core section is positioned between the first rotor core section and the third rotor core section, wherein an external diameter of the second rotor core section is smaller than an external diameter of the first rotor core section and an external diameter of the third rotor core section, while the external diameter of the first rotor core section is identical to that of the third rotor core section, the first rotor core section, the second rotor core section and the third rotor core section being eccentrically arranged to share a common central longitudinal axis, wherein a thickness of the first rotor core section is identical to that of the first armature core section, while a thickness of the second rotor core section is identical to that of the second armature core section, and a thickness of the third rotor core section is identical to that of the third armature core section, each of the first rotor core section and the third rotor core section further having k/2 magnet receiving slots longitudinally forming on an outer circumferential surface of the first rotor core section and the third rotor core section, in such a manner that the k/2 magnet receiving slots of the first rotor core section are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section are evenly distributed along a circumferential direction thereof, the magnet receiving slots of the first rotor core section being arranged not to be aligned with the magnet receiving slots of the third rotor core section with respect to the longitudinal direction of the rotor, wherein the magnet receiving slots of the first rotor core section are aligned with the stator core slots of the first armature core section respectively, while the magnet receiving slots of the third rotor core section are aligned with the stator core slots of the third armature core section respectively, such that the magnet receiving slots are positioned to correspond to the positions of the stator core slots respectively, the rotor permanent magnets being received in the magnet receiving slots respectively, wherein each of the rotor permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the rotor permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the rotor permanent magnets with respect to the rotor is identical, wherein each of the rotor permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator. 
     In a third aspect of the present invention, it provides a magnetic field modulated transverse flux multiphase permanent magnet motor, comprising a stator and a rotor, wherein the stator and the rotor are spaced apart from each other to form an air gap therebetween, the stator comprising a stator casing and m armature units, where m is a number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3, the stator casing being tubular in structure, each of the armature units comprising an armature core and an armature winding, wherein each of the armature cores has a first armature core section, a second armature core section, and a third armature core section, each of the first armature core section, the second armature core section, and the third armature core section having an annular structure and an identical external diameter, the second armature core section being positioned between the first armature core section and the third armature core section, wherein an internal diameter of the second armature core section is greater than that of the first armature core section and the third armature core section, while an internal diameter of the first armature core section is identical to that of the third armature core section, the first armature core section, the second armature core section, and the third armature core section being eccentrically arranged to share the a common central longitudinal axis, and being sequentially and securely supported in the core casing along a longitudinal direction thereof, the first armature core section and the third armature core section having a plurality of stator core slots formed on an inner circumferential surface of the first armature core section and the third armature core section, wherein the stator core slots are longitudinally formed along a longitudinal direction of the stator casing, wherein a number of the stator core slots forming on the first armature core section is equal to a number of the stator core slots forming on the third armature core section, wherein the stator core slots of the first armature core section are evenly distributed along a circumferential direction thereof, while the stator core slots of the third armature core section are evenly distributed along a circumferential direction thereof, wherein, the stator core slots of the first armature core section are arranged not to be aligned with the stator core slots of the third armature core section with respect to the radial direction of the stator, the armature winding being embedded in a space formed between the first armature core section, the second armature core section, and the third armature core section, wherein the m armature units are sequentially and securely supported in the core casing along a longitudinal direction thereof, each of the armature units being distributed along a circumferential direction of the stator casing in such a manner that each of the armature units has an electrical angle of 360°/m, the rotor comprising a rotor core and k rotor permanent magnets, where k is an even number, the rotor core having a first rotor core section, a second rotor core section, and a third rotor core section, each of the first rotor core section, the second rotor core section and the third rotor core section being annular in structure, and having an identical internal diameter, wherein the second rotor core section is positioned between the first rotor core section and the third rotor core section, wherein an external diameter of the second rotor core section is smaller than an external diameter of the first rotor core section and an external diameter of the third rotor core section, while the external diameter of the first rotor core section is identical to that of the third rotor core section, the first rotor core section, the second rotor core section and the third rotor core section being eccentrically arranged to share a common central longitudinal axis, wherein a thickness of the first rotor core section is identical to that of the first armature core section, while a thickness of the second rotor core section is identical to that of the second armature core section, and a thickness of the third rotor core section is identical to that of the third armature core section, each of the first rotor core section and the third rotor core section further having k/2 magnet receiving slots longitudinally forming on an outer circumferential surface of the first rotor core section and the third rotor core section, in such a manner that the k/2 magnet receiving slots of the first rotor core section are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section are evenly distributed along a circumferential direction thereof, wherein a number of the magnet receiving slots forming on the third rotor core section is identical to a number of the stator core slots forming on the third armature core section, wherein the rotor permanent magnets are received in the magnet receiving slots respectively, wherein each of the rotor permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the rotor permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the rotor permanent magnets with respect to the rotor is identical, wherein each of the rotor permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator. 
     In a fourth aspect of the present invention, it provides a magnetic field modulated transverse flux multiphase permanent magnet motor, comprising a stator and a rotor, wherein the stator and the rotor are spaced apart from each other to form an air gap therebetween, the stator comprising a stator casing and m armature units, where m is a number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3, the stator casing being tubular in structure, each of the armature units comprising an armature core and an armature winding, and k stator permanent magnets, where k is an even number, wherein each of the armature cores has a first armature core section, a second armature core section, and a third armature core section, each of the first armature core section, the second armature core section, and the third armature core section having an annular structure and an identical external diameter, the second armature core section being positioned between the first armature core section and the third armature core section, wherein an internal diameter of the second armature core section is greater than that of the first armature core section and the third armature core section, while an internal diameter of the first armature core section is identical to that of the third armature core section, the first armature core section, the second armature core section, and the third armature core section being eccentrically arranged to share the a common central longitudinal axis, and being sequentially and securely supported in the core casing along a longitudinal direction thereof, the first armature core section and the third armature core section having k/2 stator core slots forming on an inner circumferential surface of the first armature core section and the third armature core section, wherein the stator core slots of the first armature core section are evenly distributed along a circumferential direction thereof, while the stator core slots of the third armature core section are evenly distributed along a circumferential direction thereof, wherein the stator core slots forming on the first armature core section are symmetrically distributed with respect to the stator core slots forming on the third armature core section, the k stator permanent magnets being received in the stator core slots of the first armature core section and the third armature core section respectively, wherein each of the stator permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the stator permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the stator permanent magnets with respect to the stator is identical, wherein each of the stator permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator, the armature winding being embedded in a space formed between the first armature core section, the second armature core section, and the third armature core section, wherein the m armature units are sequentially and securely supported in the core casing along a longitudinal direction thereof, each of the armature units being distributed along a circumferential direction of the stator casing in such a manner that each of the armature units has an electrical angle of 360°/m, the rotor comprising a rotor core and k rotor permanent magnets, where k is an even number, the rotor core having a first rotor core section, a second rotor core section, and a third rotor core section, each of the first rotor core section, the second rotor core section and the third rotor core section being annular in structure, and having an identical internal diameter, wherein the second rotor core section is positioned between the first rotor core section and the third rotor core section, wherein an external diameter of the second rotor core section is smaller than an external diameter of the first rotor core section and an external diameter of the third rotor core section, while the external diameter of the first rotor core section is identical to that of the third rotor core section, the first rotor core section, the second rotor core section and the third rotor core section being eccentrically arranged to share a common central longitudinal axis, wherein a thickness of the first rotor core section is identical to that of the first armature core section, while a thickness of the second rotor core section is identical to that of the second armature core section, and a thickness of the third rotor core section is identical to that of the third armature core section, each of the first rotor core section and the third rotor core section further having k/2 magnet receiving slots longitudinally forming on an outer circumferential surface of the first rotor core section and the third rotor core section, in such a manner that the k/2 magnet receiving slots of the first rotor core section are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section are evenly distributed along a circumferential direction thereof, the magnet receiving slots of the first rotor core section being arranged not to be aligned with the magnet receiving slots of the third rotor core section  8  with respect to the longitudinal direction of the rotor, wherein the magnet receiving slots of the first rotor core section are aligned with the stator core slots of the first armature core section respectively, while the magnet receiving slots of the third rotor core section are aligned with the stator core slots of the third armature core section respectively, such that the magnet receiving slots are positioned to correspond to the positions of the stator core slots respectively, the rotor permanent magnets being received in the magnet receiving slots respectively, wherein each of the rotor permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the rotor permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the rotor permanent magnets with respect to the rotor is identical, wherein each of the rotor permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator, the rotor permanent magnets and the stator permanent magnets have the an identical magnetization direction. 
     In a fifth aspect of the present invention, it provides a magnetic field modulated transverse flux multiphase permanent magnet motor, comprising a stator and a rotor, wherein the stator and the rotor are spaced apart from each other to form an air gap therebetween, the stator comprising a stator casing and m armature units, where m is a number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3, the stator casing being tubular in structure, each of the armature units comprising an armature core and an armature winding, and k stator permanent magnets, where k is an even number, wherein each of the armature cores has a first armature core section, a second armature core section, and a third armature core section, each of the first armature core section, the second armature core section, and the third armature core section having an annular structure and an identical external diameter, the second armature core section being positioned between the first armature core section and the third armature core section, wherein an internal diameter of the second armature core section is greater than that of the first armature core section and the third armature core section, while an internal diameter of the first armature core section is identical to that of the third armature core section, the first armature core section, the second armature core section, and the third armature core section being eccentrically arranged to share the a common central longitudinal axis, and being sequentially and securely supported in the core casing along a longitudinal direction thereof, the first armature core section and the third armature core section having k/2 stator core slots forming on an inner circumferential surface of the first armature core section and the third armature core section, wherein the stator core slots of the first armature core section are evenly distributed along a circumferential direction thereof, while the stator core slots of the third armature core section are evenly distributed along a circumferential direction thereof, the stator core slots forming on the first armature core section being arranged not to be aligned with the stator core slots forming on the third armature core section with respect to the circumferential direction of the stator, the k stator permanent magnets being received in the stator core slots of the first armature core section and the third armature core section respectively, wherein each of the stator permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the stator permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the stator permanent magnets with respect to the stator is identical, wherein each of the stator permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator, the armature winding being embedded in a space formed between the first armature core section, the second armature core section, and the third armature core section, wherein the m armature units are sequentially and securely supported in the core casing along a longitudinal direction thereof, each of the armature units being distributed along a circumferential direction of the stator casing in such a manner that each of the armature units has an electrical angle of 360°/m, the rotor being tubular in structure, and having k/2 magnet receiving slots longitudinally and evenly forming on an outer circumferential surface of the rotor, the rotor further comprising a plurality of rotor permanent magnets received in the magnet receiving slots respectively, wherein each of the rotor permanent magnets is elongated in shape and is arranged to create one of radial magnetization and parallel magnetization, the rotor permanent magnets having identical direction of magnetization, so that a polarity of each pole of each of the rotor permanent magnets with respect to the rotor is identical, wherein each of the rotor permanent magnets has one of a N-pole and a S-pole facing toward the air gap formed between the rotor and the stator, the rotor permanent magnets and the stator permanent magnets having an identical magnetization direction. 
     Beneficial Effects 
     The present invention provides a magnetic field modulated transverse flux multiphase permanent magnet motor which has the advantages of having relatively high reliability, low energy loss, high torque density, low manufacturing cost, and simple structure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic diagram of a conventional multiphase permanent magnet synchronous motor. 
         FIG. 2  is a sectional side view of an armature unit of a magnetic field modulated transverse flux multiphase permanent magnet motor according to a first preferred embodiment of the present invention. 
         FIG. 3  is a sectional view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor along plane A-A of  FIG. 2 . 
         FIG. 4  is a right side view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor according to the first preferred embodiment of the present invention. 
         FIG. 5  is a sectional side view of an armature unit of a magnetic field modulated transverse flux multiphase permanent magnet motor according to a second preferred embodiment of the present invention. 
         FIG. 6  is a sectional view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor along plane B-B of  FIG. 5 . 
         FIG. 7  is a right side view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor according to the second preferred embodiment of the present invention. 
         FIG. 8  is a sectional side view of an armature unit of a magnetic field modulated transverse flux multiphase permanent magnet motor according to a third preferred embodiment of the present invention. 
         FIG. 9  is a sectional view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor along plane C-C of  FIG. 8 . 
         FIG. 10  is a right side view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor according to the third preferred embodiment of the present invention. 
         FIG. 11  is a sectional side view of an armature unit of a magnetic field modulated transverse flux multiphase permanent magnet motor according to a fourth preferred embodiment of the present invention. 
         FIG. 12  is a sectional view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor along plane D-D of  FIG. 11 . 
         FIG. 13  is a right side view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor according to the fourth preferred embodiment of the present invention. 
         FIG. 14  is a sectional side view of an armature unit of a magnetic field modulated transverse flux multiphase permanent magnet motor according to a fifth preferred embodiment of the present invention. 
         FIG. 15  is a sectional view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor along plane E-E of  FIG. 14 . 
         FIG. 16  is a right side view of the armature unit of the magnetic field modulated transverse flux multiphase permanent magnet motor according to the fifth preferred embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Embodiment 1 
     Referring to  FIG. 2  to  FIG. 4  of the drawings, schematic diagrams of a magnetic field modulated transverse flux multiphase permanent magnet motor are illustrated, in which it comprises a stator and a rotor, wherein the stator and the rotor is spaced apart from each other to form an air gap therebetween. The stator comprises a stator casing  1  and m armature units, where m is the number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3. Each of the armature units comprises an armature core and an armature winding  2 . Each of the armature cores comprises n stator core teeth, wherein n is an integer. Each of the stator core teeth has a first stator teeth section  3 , a second stator teeth section  4 , and a third stator teeth section  5 . Each of the first stator teeth section  3 , the second stator teeth section  4 , and the third stator teeth section  5  has an annular structure or cross section and has the same external diameter. Moreover, the second stator teeth section  4  is positioned between the first stator teeth section  3  and the third stator teeth section  5 , wherein an internal diameter of the second stator teeth section  4  is greater than that of the first stator teeth section  3  and the third stator teeth section  5 , while an internal diameter of the first stator teeth section  3  is the same as that of the third stator teeth section  5 . The first stator teeth section  3 , the second stator teeth section  4 , and the third stator teeth section  5  are eccentrically arranged so that they share the same central longitudinal axis. The armature winding  2  is embedded in a space formed between the first stator teeth section  3 , the second stator teeth section  4  and the third stator teeth section  5 . The stator casing  1  is tubular in structure. The stator casing  1  has a plurality of casing slots  100  formed on an inner surface thereof, wherein the casing slots  100  are longitudinally formed along a longitudinal direction of the stator casing  1 . The number of casing slots  100  formed on the stator casing  1  is equal to the number of stator core teeth. The stator core teeth are engaged with the casing slots  100  respectively from a circumferential direction of the stator casing  1 . Moreover a transverse depth of each of the stator core teeth is greater than or equal to a transverse depth of the corresponding casing slot  100  of the stator casing  1 . The armature units are sequentially arranged along a longitudinal direction of the stator casing  1 , wherein each of the armature units are distributed along the circumferential direction of the stator casing  1  in such a manner that each of the armature units has an electrical angle of 360°/m. The rotor comprises a rotor core and k rotor permanent magnets  9 , where k is an even number. The rotor core has a first rotor core section  6 , a second rotor core section  7 , and a third rotor core section  8 . Each of the first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  is annular in structure, and they have the same internal diameter. The second rotor core section  7  is positioned between the first rotor core section  6  and the third rotor core section  8 , wherein an external diameter of the second rotor core section  7  is smaller than an external diameter of the first rotor core section  6  and an external diameter of the third rotor core section  8 . Note that the external diameter of the first rotor core section  6  is the same as that of the third rotor core section  8 . The first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  are eccentrically arranged so that they share the same central longitudinal axis. A thickness t 6  of the first rotor core section  6  is the same as a thickness t 3  of the first stator teeth section  3 , while a thickness t 7  of the second rotor core section  7  is the same as a thickness t 4  of the second stator teeth section  4 , and a thickness t 8  of the third rotor core section  8  is the same as a thickness t 5  of the third stator teeth section  5 . For each of the armature units, the first rotor core section  6 , the second rotor core section  7 , and the third rotor core section  8  of the rotor core are aligned with the corresponding first stator teeth section  3 , the fourth stator teeth section  4 , and the third stator teeth section  5  respectively. Furthermore, each of the first rotor core section  6  and the third rotor core section  8  further has k/2 magnet receiving slots longitudinally formed on an outer surface of the first rotor core section  6  and the third rotor core section  8 , in such a manner that the k/2 magnet receiving slots of the first rotor core section  6  are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section  8  are also evenly distributed along a circumferential direction thereof. With respect to the longitudinal direction of the rotor, the magnet receiving slots of the first rotor core section  6  are arranged not to be aligned (i.e. offset) with the magnet receiving slots of the third rotor core section  8  by a half pitch distance. The rotor permanent magnets  9  are received in the magnet receiving slots respectively. Each of the rotor permanent magnets  9  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The rotor permanent magnets  9  have the same direction or polarity of magnetization. In other words, the polarity of each pole of each of the rotor permanent magnets  9  with respect to the rotor is the same. Thus, each of the rotor permanent magnets  9  may have its N-pole or S-pole facing toward the air gap formed between the rotor and the stator. 
     Embodiment 2 
     Referring to  FIG. 5  to  FIG. 7  of the drawings, schematic diagrams of a magnetic field modulated transverse flux multiphase permanent magnet motor are illustrated, in which it comprises a stator and a rotor, wherein the stator and the rotor is spaced apart from each other to form an air gap therebetween. The stator comprises a stator casing  1  and m armature units, where m is the number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3. The stator casing  1  is tubular in structure. Each of the armature units comprises an armature core and an armature winding  2 . The armature core has a first armature core section  10 , a second armature core section  11 , and a third armature core section  12 . Each of the first armature core section  10 , the second armature core section  11 , and the third armature core section  12  has an annular structure or cross section and has the same external diameter. Moreover, the second armature core section  11  is positioned between the first armature core section  10  and the third armature core section  12 , wherein an internal diameter of the second armature core section  11  is greater than that of the first armature core section  10  and the third armature core section  12 , while an internal diameter of the first armature core section  10  is the same as that of the third armature core section  12 . The first armature core section  10 , the second armature core section  11 , and the third armature core section  12  are eccentrically arranged so that they share the same central longitudinal axis, and are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. The first armature core section  10  and the third armature core section  12  has a plurality of stator core slots formed on an inner circumferential surface of the first armature core section  10  and the third armature core section  12 , wherein the stator core slots are longitudinally formed along a longitudinal direction of the stator casing  1 . The number of stator core slots formed on the first armature core section  10  is equal to the number of the stator core slots formed on the third armature core section  12 . The stator core slots of the first armature core section  10  are evenly distributed along a circumferential direction thereof. Similarly, the stator core slots of the third armature core section  12  are evenly distributed along a circumferential direction thereof. The stator core slots formed on the first armature core section  10  are symmetrically distributed with respect to the stator core slots formed on the third armature core section  12 . The armature winding  2  is embedded in a space formed between the first armature core section  10 , the second armature core section  11 , and the third armature core section  12 . The m armature units are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. Each of the armature units are distributed along the circumferential direction of the stator casing  1  in such a manner that each of the armature units has an electrical angle of 360°/m. The rotor comprises a rotor core and k rotor permanent magnets  9 , where k is an even number. The rotor core has a first rotor core section  6 , a second rotor core section  7 , and a third rotor core section  8 . Each of the first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  is annular in structure, and they have the same internal diameter. The second rotor core section  7  is positioned between the first rotor core section  6  and the third rotor core section  8 , wherein an external diameter of the second rotor core section  7  is smaller than an external diameter of the first rotor core section  6  and an external diameter of the third rotor core section  8 . Note that the external diameter of the first rotor core section  6  is the same as that of the third rotor core section  8 . The first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  are eccentrically arranged so that they share the same central longitudinal axis. A thickness t 6  of the first rotor core section  6  is the same as a thickness t 10  of the first armature core section  10 , while a thickness t 7  of the second rotor core section  7  is the same as a thickness t 11  of the second armature core section  11 , and a thickness t 8  of the third rotor core section  8  is the same as a thickness t 12  of the third armature core section  12 . Each of the first rotor core section  6  and the third rotor core section  8  further has k/2 magnet receiving slots longitudinally formed on an outer circumferential surface of the first rotor core section  6  and the third rotor core section  8 , in such a manner that the k/2 magnet receiving slots of the first rotor core section  6  are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section  8  are also evenly distributed along a circumferential direction thereof. With respect to the longitudinal direction of the rotor, the magnet receiving slots of the first rotor core section  6  are arranged not to be aligned (i.e. offset) with the magnet receiving slots of the third rotor core section  8  by a half pitch distance. The magnet receiving slots of the first rotor core section  6  correspond to (i.e. are aligned with) the stator core slots of the first armature core section  10  respectively, while the magnet receiving slots of the third rotor core section  8  correspond to (i.e. aligned with) the stator core slots of the third armature core section  12  respectively. In other words, the magnet receiving slots are positioned to correspond to the positions of the stator core slots respectively. The rotor permanent magnets  9  are received in the magnet receiving slots respectively. Each of the rotor permanent magnets  9  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The rotor permanent magnets  9  have the same direction or polarity of magnetization. In other words, the polarity of each pole of each of the rotor permanent magnets  9  with respect to the rotor is the same. Thus, each of the rotor permanent magnets  9  may have its N-pole or S-pole facing toward the air gap formed between the rotor and the stator. 
     Embodiment 3 
     Referring to  FIG. 8  to  FIG. 10  of the drawings, schematic diagrams of a magnetic field modulated transverse flux multiphase permanent magnet motor are illustrated, in which it comprises a stator and a rotor, wherein the stator and the rotor is spaced apart from each other to form an air gap therebetween. The stator comprises a stator casing  1  and m armature units, where m is the number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3. The stator casing  1  is tubular in structure. Each of the armature units comprises an armature core and an armature winding  2 . The armature core has a first armature core section  10 , a second armature core section  11 , and a third armature core section  12 . Each of the first armature core section  10 , the second armature core section  11 , and the third armature core section  12  has an annular structure or cross section and has the same external diameter. Moreover, the second armature core section  11  is positioned between the first armature core section  10  and the third armature core section  12 , wherein an internal diameter of the second armature core section  11  is greater than that of the first armature core section  10  and the third armature core section  12 , while an internal diameter of the first armature core section  10  is the same as that of the third armature core section  12 . The first armature core section  10 , the second armature core section  11 , and the third armature core section  12  are eccentrically arranged so that they share the same central longitudinal axis, and are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. The first armature core section  10  and the third armature core section  12  has a plurality of stator core slots formed on an inner circumferential surface of the first armature core section  10  and the third armature core section  12 , wherein the stator core slots are longitudinally formed along a longitudinal direction of the stator casing  1 . The number of stator core slots formed on the first armature core section  10  is equal to the number of the stator core slots formed on the third armature core section  12 . The stator core slots of the first armature core section  10  are evenly distributed along a circumferential direction thereof. Similarly, the stator core slots of the third armature core section  12  are evenly distributed along a circumferential direction thereof. With respect to the radial direction of the stator, the stator core slots of the first armature core section  10  are arranged not to be aligned (i.e. offset) with the stator core slots of the third armature core section  12  by a half pitch distance. The armature winding  2  is embedded in a space formed between the first armature core section  10 , the second armature core section  11 , and the third armature core section  12 . The m armature units are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. Each of the armature units are distributed along the circumferential direction of the stator casing  1  in such a manner that each of the armature units has an electrical angle of 360°/m. The rotor comprises a rotor core and k rotor permanent magnets  9 , where k is an even number. The rotor core has a first rotor core section  6 , a second rotor core section  7 , and a third rotor core section  8 . Each of the first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  is annular in structure, and they have the same internal diameter. The second rotor core section  7  is positioned between the first rotor core section  6  and the third rotor core section  8 , wherein an external diameter of the second rotor core section  7  is smaller than an external diameter of the first rotor core section  6  and an external diameter of the third rotor core section  8 . Note that the external diameter of the first rotor core section  6  is the same as that of the third rotor core section  8 . The first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  are eccentrically arranged so that they share the same central longitudinal axis. A thickness t 6  of the first rotor core section  6  is the same as a thickness t 10  of the first armature core section  10 , while a thickness t 7  of the second rotor core section  7  is the same as a thickness t 11  of the second armature core section  11 , and a thickness t 8  of the third rotor core section  8  is the same as a thickness t 12  of the third armature core section  12 . Each of the first rotor core section  6  and the third rotor core section  8  further has k/2 magnet receiving slots longitudinally formed on an outer circumferential surface of the first rotor core section  6  and the third rotor core section  8 , in such a manner that the k/2 magnet receiving slots of the first rotor core section  6  are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section  8  are also evenly distributed along a circumferential direction thereof. The number of magnet receiving slots formed on the third rotor core section is the same as the number of stator core slots formed on the third armature core section  12 . The rotor permanent magnets  9  are received in the magnet receiving slots respectively. Each of the rotor permanent magnets  9  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The rotor permanent magnets  9  have the same direction or polarity of magnetization. In other words, the polarity of each pole of each of the rotor permanent magnets  9  with respect to the rotor is the same. Thus, each of the rotor permanent magnets  9  may have its N-pole or S-pole facing toward the air gap formed between the rotor and the stator. 
     Embodiment 4 
     Referring to  FIG. 11  to  FIG. 13  of the drawings, schematic diagrams of a magnetic field modulated transverse flux multiphase permanent magnet motor are illustrated, in which it comprises a stator and a rotor, wherein the stator and the rotor is spaced apart from each other to form an air gap therebetween. The stator comprises a stator casing  1  and m armature units, where m is the number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3. The stator casing  1  is tubular in structure. Each of the armature units comprises an armature core, an armature winding  2 , and k stator permanent magnets  13 , where k is an even number. The armature core has a first armature core section  10 , a second armature core section  11 , and a third armature core section  12 . Each of the first armature core section  10 , the second armature core section  11 , and the third armature core section  12  has an annular structure or cross section and has the same external diameter. Moreover, the second armature core section  11  is positioned between the first armature core section  10  and the third armature core section  12 , wherein an internal diameter of the second armature core section  11  is greater than that of the first armature core section  10  and the third armature core section  12 , while an internal diameter of the first armature core section  10  is the same as that of the third armature core section  12 . The first armature core section  10 , the second armature core section  11 , and the third armature core section  12  are eccentrically arranged so that they share the same central longitudinal axis, and are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. Each of the first armature core section  10  and the third armature core section  12  has a k/2 stator core slots formed on an inner circumferential surface of the corresponding armature core section. The k/2 stator core slots of the first armature core section  10  are evenly distributed along a circumferential direction thereof. Similarly, the k/2 stator core slots of the third armature core section  12  are evenly distributed along a circumferential direction thereof. The stator core slots formed on the first armature core section  10  are symmetrically distributed with respect to the stator core slots formed on the third armature core section  12 . The k stator permanent magnets  13  are received in the stator core slots of the first armature core section  10  and the third armature core section  12  respectively. Each of the stator permanent magnets  13  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The stator permanent magnets  13  have the same direction or polarity of magnetization direction. In other words, the polarity of each pole of each of the stator permanent magnets  13  with respect to the stator is the same. Thus, each of the stator permanent magnets  13  may have its N-pole or S-pole facing toward the air gap formed between the rotor and the stator. The armature winding  2  is embedded in a space formed between the first armature core section  10 , the second armature core section  11 , and the third armature core section  12 . The m armature units are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. Each of the armature units is distributed along the circumferential direction of the stator casing  1  in such a manner that each of the armature units has an electrical angle of 360°/m. The rotor comprises a rotor core and k rotor permanent magnets  9 , where k is an even number. The rotor core has a first rotor core section  6 , a second rotor core section  7 , and a third rotor core section  8 . Each of the first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  is annular in structure, and they have the same internal diameter. The second rotor core section  7  is positioned between the first rotor core section  6  and the third rotor core section  8 , wherein an external diameter of the second rotor core section  7  is smaller than an external diameter of the first rotor core section  6  and an external diameter of the third rotor core section  8 . Note that the external diameter of the first rotor core section  6  is the same as that of the third rotor core section  8 . The first rotor core section  6 , the second rotor core section  7  and the third rotor core section  8  are eccentrically arranged so that they share the same central longitudinal axis. A thickness t 6  of the first rotor core section  6  is the same as a thickness t 10  of the first armature core section  10 , while a thickness t 7  of the second rotor core section  7  is the same as a thickness t 11  of the second armature core section  11 , and a thickness t 8  of the third rotor core section  8  is the same as a thickness t 12  of the third armature core section  12 . Each of the first rotor core section  6  and the third rotor core section  8  further has k/2 magnet receiving slots longitudinally formed on an outer circumferential surface of the first rotor core section  6  and the third rotor core section  8 , in such a manner that the k/2 magnet receiving slots of the first rotor core section  6  are evenly distributed along a circumferential direction thereof, while the k/2 magnet receiving slots of the third rotor core section  8  are also evenly distributed along a circumferential direction thereof. With respect to the radial direction of the rotor, the magnet receiving slots of the first rotor core section  6  are arranged not to be aligned (i.e. offset) with the magnet receiving slots of the third rotor core section  8  by a half pitch distance. The magnet receiving slots of the first rotor core section  6  correspond to (i.e. are aligned with) the stator core slots of the first armature core section  10  respectively, while the magnet receiving slots of the third rotor core section  8  correspond to (i.e. aligned with) the stator core slots of the third armature core section  12  respectively. In other words, the magnet receiving slots are positioned to correspond to the positions of the stator core slots respectively. The rotor permanent magnets  9  are received in the magnet receiving slots respectively. Each of the rotor permanent magnets  9  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The rotor permanent magnets  9  have the same direction or polarity of magnetization. In other words, the polarity of each pole of each of the rotor permanent magnets  9  with respect to the rotor is the same. Thus, each of the rotor permanent magnets  9  may have its N-pole or S-pole facing toward the air gap formed between the rotor and the stator. The rotor permanent magnets  9  and the stator permanent magnets  13  have the same magnetization direction. 
     Embodiment 5 
     Referring to  FIG. 11  to  FIG. 13  of the drawings, schematic diagrams of a magnetic field modulated transverse flux multiphase permanent magnet motor are illustrated, in which it comprises a stator and a rotor, wherein the stator and the rotor is spaced apart from each other to form an air gap therebetween. The stator comprises a stator casing  1  and m armature units, where m is the number of phases of the magnetic field modulated transverse flux multiphase permanent magnet motor, and m≧3. The stator casing  1  is tubular in structure. Each of the armature units comprises an armature core, an armature winding  2 , and k stator permanent magnets  13 , where k is an even number. The armature core has a first armature core section  10 , a second armature core section  11 , and a third armature core section  12 . Each of the first armature core section  10 , the second armature core section  11 , and the third armature core section  12  has an annular structure or cross section and has the same external diameter. Moreover, the second armature core section  11  is positioned between the first armature core section  10  and the third armature core section  12 , wherein an internal diameter of the second armature core section  11  is greater than that of the first armature core section  10  and the third armature core section  12 , while an internal diameter of the first armature core section  10  is the same as that of the third armature core section  12 . The first armature core section  10 , the second armature core section  11 , and the third armature core section  12  are eccentrically arranged so that they share the same central longitudinal axis, and are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. Each of the first armature core section  10  and the third armature core section  12  has a k/2 stator core slots formed on an inner circumferential surface of the corresponding armature core section. The k/2 stator core slots of the first armature core section  10  are evenly distributed along a circumferential direction thereof. Similarly, the k/2 stator core slots of the third armature core section  12  are evenly distributed along a circumferential direction thereof. With respect to the circumferential direction of the stator, the stator core slots formed on the first armature core section  10  are arranged not to be aligned (i.e. offset) with the stator core slots formed on the third armature core section  12  by a half pitch distance. The k stator permanent magnets  13  are received in the stator core slots of the first armature core section  10  and the third armature core section  12  respectively. Each of the stator permanent magnets  13  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The stator permanent magnets  13  have the same direction or polarity of magnetization direction. In other words, the polarity of each pole of each of the stator permanent magnets  13  with respect to the stator is the same. Thus, each of the stator permanent magnets  13  may have its N-pole or S-pole facing toward the air gap formed between the rotor and the stator. The armature winding  2  is embedded in a space formed between the first armature core section  10 , the second armature core section  11 , and the third armature core section  12 . The m armature units are sequentially and securely supported in the core casing  1  along a longitudinal direction thereof. Each of the armature units is distributed along the circumferential direction of the stator casing  1  in such a manner that each of the armature units has an electrical angle of 360°/m. The rotor is tubular in structure, and has k/2 magnet receiving slots longitudinally and evenly formed on an outer circumferential surface of the rotor. The rotor permanent magnets  9  are received in the magnet receiving slots respectively. Each of the rotor permanent magnets  9  is elongated in shape and may be arranged to create radial magnetization or parallel magnetization. The rotor permanent magnets  9  have the same direction or polarity of magnetization. 
     Embodiment 6 
     the difference between the sixth embodiment and the first through fifth embodiment embodiments described above is that the armature core and the rotor core are configured by magnetic material having high permeability. The other structures and features of the sixth embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above. 
     Embodiment 7 
     the difference between the seventh embodiment and the first through fifth embodiment embodiments described above is that the stator casing  1  is configured by non-magnetic material. The other structures and features of the seventh embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above. 
     Embodiment 8 
     the difference between the eighth embodiment and the first through fifth embodiment embodiments described above is that the number of armature units of the stator is greater than or equal to one. The armature units having the same phase are positioned correspondingly along a circumferential direction of the stator. The other structures and features of the eighth embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above. 
     Embodiment 9 
     the difference between the ninth embodiment and the first through fifth embodiment embodiments described above is that the magnetic field modulated transverse flux multiphase permanent magnet motor utilizes internal rotor structure. The other structures and features of the ninth embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above. 
     Embodiment 10 
     the difference between the tenth embodiment and the first through fifth embodiment embodiments described above is that the magnetic field modulated transverse flux multiphase permanent magnet motor utilizes external rotor structure. The other structures and features of the tenth embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above. 
     Embodiment 11 
     the difference between the eleventh embodiment and the first through fifth embodiment embodiments described above is that the magnetic field modulated transverse flux multiphase permanent magnet motor comprises two rotors. The other structures and features of the eleventh embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above. 
     Embodiment 12 
     the difference between the twelfth embodiment and the first through fifth embodiment embodiments described above is that the magnetic field modulated transverse flux multiphase permanent magnet motor comprises two stators. The other structures and features of the twelfth embodiment of the present invention is similar to the first through fifth embodiment of the present invention as described above.