Electric rotating machine

Abstract

Electric rotating machine (M) with one axis, comprising: a first stator (100) which has drive stator windings (101) which generate a stator-side magnetic flux when supplied with alternating current; a first rotor (200) which accommodates the first stator (100) to surround an outer circumferential surface (120a) of the first stator (100), and which has drive rotor windings (201) with which the stator-side magnetic flux generated by the drive stator windings (101) couples, and which is rotated due to the generation of a torque between the rotor-side magnetic flux generated by the drive rotor windings (201) and the stator-side magnetic flux; a second stator (100) arranged closer to the axis than to an inner circumferential surface of the first stator (100) and surrounded by the inner circumferential surface, the second stator (100) having a DC-excited stator winding (102) which generates a magnetic flux when supplied with a DC current generated by converting the AC current supplied to the drive stator windings (101); and a second rotor (300) which is arranged closer to the axis than the second stator (100) and is surrounded by the inner circumferential surface, wherein the second rotor (300) has AC induction rotor windings (301) which induce an alternating current by means of the magnetic field generated by the DC excited stator winding (102) of the second stator (100), wherein the first stator (100), the first rotor (200), the second stator (100) and the second rotor (300) are aligned coaxially along the axis, and wherein the alternating current induced by the AC induction rotor windings (301) of the second rotor (300) is supplied to the drive rotor windings (201) of the first rotor (200).

Description

[Technical field]

[0001] The present invention relates to an electric rotating machine and in particular to an electric rotating machine with secondary excited induction. [Technical field]

[0002] Electric rotating machines are installed in various devices as an energy source. In vehicles, for example, an electric rotating machine is installed in an electric vehicle to serve as an energy source, or it is installed in a hybrid electric vehicle together with an internal combustion engine to serve as an energy source.

[0003] An induction motor is a known type of electric rotating machine in which the supply of alternating current to stator-side wound coils generates a rotating magnetic field, which induces a current through rotor-side wound coils via electromagnetic induction, thus generating a torque between the stator-side rotating magnetic field and the rotor-side wound coils. Various means, including a secondary excitation inductor, are known for supplying external energy to the rotor-side wound coils in such induction motors.

[0004] Such a secondary-excitation induction motor requires a slip ring, which is located at one end of a shaft, so that the rotor can supply alternating current to the wound coils. The slip ring is subject to wear, which raises the issues of maintenance and reliability.

[0005] To solve the above-mentioned problem, JP 2011- 55 569 A describes a technique in which a main motor structure and an auxiliary motor structure are coaxially coupled and the auxiliary motor structure is caused to generate an alternating current to supply the main motor structure (or wound coils) with the alternating current.

[0006] WO 00 / 67 355 A1 discloses a rotating main electrical machine comprising a shaft, an AC rotor winding, an AC stator winding, a shaft-rotating converter, and an AC regulating machine. The regulating machine comprises a shaft-rotating rotor, an AC rotor winding, and a stator winding. The stator winding is connected to the rotor winding via a converter. The stator winding is supplied with DC current. The rotor winding acts as an AC converter and is connected to the rotor winding via the converter.

[0007] DE 102 30 404 A1 discloses a rotating electric machine capable of achieving sufficient power without increasing the rotor speed or the number of turns in the armature coil. The rotating electric machine consists of a stator and a rotor, the stator comprising an armature and a field element. An armature core of the armature contains an armature coil. A rear support is attached to a cylindrical section of a field core, which forms the field element. A field coil is wound around a salient pole of the field core. The rotor consists of a rotating shaft, a disk section attached to it, a rotor core attached to it, and a winding.The rotor core is rotatable by rotating the rotating shaft on one side of the inner diameter of the armature core and on one side of the outer diameter of the field core via an air gap, wherein an inner side coil is provided on a section of the side of the inner diameter facing the field core. An outer side coil is provided on a section of the side of the outer diameter facing the armature core.

[0008] US Patent 8,330,409 B2 discloses a drive unit comprising a rotating electric machine with a stator mounted on a housing and a rotor positioned opposite the stator and capable of rotating relative to it. The rotor has a radial rotor positioned radially opposite the stator and two axial rotors positioned parallel to the rotor's axis of rotation and mechanically and magnetically connected to the radial rotor. The stator comprises an annular core section and an armature winding with a plurality of phases wound toroidally around this annular core section.The radial rotor comprises a substantially cylindrical radial core and a plurality of radial permanent magnets arranged on the outer circumferential section of the radial core and radially opposite the stator. The axial rotors each comprise axial cores and axial permanent magnets arranged on the side faces of the axial cores to counteract the stator in the direction of the rotor's axis of rotation. Field windings are provided in the stator to control the magnetic flux, which interacts with the stator's rotating magnetic field. Also included are an inverter capable of converting direct current from a DC power supply into alternating current and supplying it to the armature winding, and a rectifier circuit capable of rectifying the alternating current converted by the inverter and supplied to the armature winding into direct current and supplying it to the field windings.

[0009] US Patent 2008 / 0136272A1 discloses a rotating electrical machine capable of easily winding a stator winding around a stator core. In this rotating electrical machine, in which a rotor rotates relative to a stator, the rotor surrounds a field winding wound around a rotating shaft. The rotor includes a rotor core surrounding the field winding and a rotor pawl magnet pole on a section of the rotor opposite a pawl magnet pole of the stator core. The stator has a stator winding wound in a ring around an outer circumference of the rotor and a stator core having stator pawl magnet poles extending alternately from both axial sides of a section of the stator opposite the rotor and surrounding a circumference of the stator winding. [Summary of the invention][Technical problem]

[0010] In the electric rotating machine described in JP 2011-55569A, i.e., the secondary excitation induction motor, the strength was increased by omitting the slip ring. However, it requires two separate power supply systems for the main motor and auxiliary motor structures.

[0011] The motor structure described in JP 2011- 55 569 A requires two inverters, even though they share a common battery, and does not solve the problem of increased cost and size.

[0012] Consequently, the object of the present invention is to provide a cost-effective and small electric rotating machine with secondary excited induction by forming a motor structure in which the secondary excitation is carried out with a single energy source. [Solution to the task]

[0013] According to one aspect of the invention, an electric rotating machine with one axis is provided, comprising: a first stator with drive stator windings which, when supplied with alternating current, generate a stator-side magnetic flux; a first rotor which accommodates the first stator in order to surround an outer circumferential surface of the first stator and which has drive rotor windings with which the stator-side magnetic flux generated by the drive stator windings couples, and which is rotated due to the generation of a torque between the rotor-side magnetic flux generated by the drive rotor windings and the stator-side magnetic flux;a second stator arranged closer to the axis than to an inner circumferential surface of the first stator and surrounded by the inner circumferential surface, the second stator having a DC-excited stator winding which generates a magnetic flux when supplied with a DC current generated by converting the AC current supplied to the drive stator windings;and a second rotor, which is arranged closer to the axis than the second stator and is surrounded by the inner circumferential surface, wherein the second rotor has AC induction rotor windings in which an alternating current is induced by means of the stator winding of the second stator excited by the DC current, wherein the first stator, the first rotor, the second stator and the second rotor are coaxially aligned along the axis, and wherein the alternating current induced by the AC induction rotor windings of the second rotor is supplied to the drive rotor windings of the first rotor. [Advantageous effects of the invention]

[0014] According to one aspect of the present invention, by simply supplying the drive stator windings of a first stator with alternating current from an energy source, a torque is generated due to the electromagnetic induction between the drive stator windings of the first stator and the drive rotor windings of a first rotor, and a direct current is provided via a direct current excited stator winding of a second stator to generate an electric field which causes the generation of alternating current in alternating current induction rotor windings of a second rotor in order to make the generated alternating current available to the drive rotor windings of a second rotor.

[0015] Thus, a cost-effective and small electrical rotating machine, such as a secondary excitation induction motor, can be provided, in which the secondary excitation is carried out with a single energy source. [Brief description of the drawings] Fig. Figure 1 is a perspective view of an electric rotating machine according to an embodiment of the present invention. Fig. Figure 2 is a perspective view of a stator. Fig. Figure 3 is a perspective view of an inner rotor. Fig. Figure 4 is an exploded view of the wiring between the inner rotor and an outer rotor. Fig. 5 is a circuit diagram of an electrical circuit. [Description of embodiments]

[0016] In the following, an embodiment of the present invention will be described in more detail with reference to the drawings. Fig. 1, Fig. 2, Fig. 3, Fig. 4 to Fig. Figure 5 shows views of an electric rotating machine according to an embodiment of the present invention.

[0017] In Fig. 1 comprises an electrical rotating machine M with secondary excited induction: a stator 100, which is essentially cylindrical; an outer rotor 200, as the first rotor, which is essentially cylindrical and is arranged around the stator 100 and rotatably receives it; and an inner rotor 300, as the second rotor, which is essentially cylindrical and is arranged inside the stator 100 and rotatably receives it.

[0018] As described below, the rotating electric machine M is designed such that the generation of torque allows rotation of the outer rotor 200 by causing a primary excited electromagnetic induction between the stator 100 and the outer rotor 200 by supplying a three-phase alternating current to the stator 100 as a driving current. Furthermore, the rotating electric machine M is configured to supply the outer rotor 200 with a three-phase alternating current as a driving current, which is generated separately by a secondary excited electromagnetic induction between the stator 100 and the inner rotor 300 using the alternating current supplied to the stator 100.

[0019] In other words, the rotating electric machine M is constructed such that it has a structure in which the generation of torque allows rotation of the outer rotor 200 by supplying the stator 100 with a three-phase alternating current from the external energy source as a driving current to cause the secondary excited induction. The rotating electric machine M is therefore a machine with secondary excited induction that exhibits exceptional strength and can be miniaturized, requires no slip ring or multiple inverters, or in other words, does not require a power supply to the rotor side from the external energy source, making it suitable, for example, for installation in hybrid electric vehicles or electric vehicles.

[0020] In the electric rotating machine M, a shaft (not shown), serving as a rotating drive shaft, brings together the axes of the stator 100, the outer rotor 200, and the inner rotor 300 and aligns them with their common axis. This shaft is attached to the outer rotor 200 and the inner rotor 300 for coaxial rotation, with the outer rotor 200 and the inner rotor 300 rotating as a unit (hereinafter referred to as "unified rotation"). For example, one axial end of the stator 100 is attached to a body shell of a vehicle or the like. Conversely, the inner rotor 300 is rotatably mounted on the body shell of the vehicle or the like on a shaft that passes through both axial ends of the inner rotor 300, which is rotatably mounted on bearings arranged at the opposite axial ends of the stator 100.Furthermore, on the one hand, the side of the outer rotor 200 opposite the body housing is attached to a ring-shaped element for uniform rotation with the inner rotor 300, and on the other hand, its side facing the body housing is rotatably mounted on a bearing on the stator 100.

[0021] As in Fig. As shown in Figure 2, the stator 100 is formed in one piece from a soft magnetic material and comprises a cylindrical stator base plate 110 and a plurality of stator teeth 120 formed on an outer circumference of the stator base plate 110.

[0022] The stator teeth 120 extend radially from the axis of rotation and have essentially the same width along the entire axial direction of the stator base plate 110. They are integrally formed with the stator base plate 110 such that they are arranged parallel to each other circumferentially along an outer circumference of the stator base plate 110. The end section of each stator tooth 120 is formed in a flange 121 that projects in opposite circumferential directions. The outer circumferential surface 120a of each flange 121 opposite the outer rotor 200 is wider in the circumferential direction than the portion of the associated stator tooth 120 that is located near the stator base plate 110.

[0023] On the stator teeth 120, a plurality of drive stator windings 101 are formed by a distributed winding of wires in slots 129 (q=2, where q is the number of slots per phase and per pole), wherein the slots are each formed by the opposite sides of two adjacent stator teeth 120.

[0024] The drive stator windings 101 are divided and connected in series for each phase, corresponding to three phases (U-phase, V-phase, W-phase), and are arranged parallel to each other along the circumference, forming part of a circuit 500 described below. In the present embodiment, the drive stator windings 101 are described as distributed windings only by way of example. This is not a limiting characteristic. Rather, the coils can also be lump-wound.

[0025] As in Fig. As shown in Figure 1, the outer rotor 200 is formed in one piece from a soft magnetic material and, similar to the stator 100, comprises a cylindrical outer base plate 210 and a plurality of rotor teeth 220 formed on an inner circumference of the outer base plate 210 (see also Figure 1). Fig. 4).

[0026] The rotor teeth 220 extend radially from the outer base plate 210 towards the axis of rotation and have essentially the same width along the entire axial direction of the outer base plate 210. They are integrally formed with the outer base plate 210 such that they are arranged parallel to each other circumferentially along an inner circumference of the outer base plate 210. The end section of each rotor tooth 220, in the radial direction towards the axis of rotation, is formed in a flange 221 that projects in opposite circumferential directions. (see Fig. 4) The inner circumferential surface 220a of each flange 121 opposite the stator 100 is wider in the circumferential direction than the portion of the associated rotor tooth 220 located near the outer base plate 210. The outer rotor 200 receives the stator 100 such that the stator 100 is rotatable within the outer rotor 200, with the inner circumferential surface 220a of each rotor tooth 220 opposite the outer circumferential surface 120a of each stator tooth 120 of the stator 100 on both sides of a gap G1.

[0027] On the rotor teeth 220, a plurality of drive stator windings 201 are formed by a distributed winding of wires in slots (q=2, where q is the number of slots per phase and per pole), wherein the slots are each formed by the opposite sides of two adjacent rotor teeth 220.

[0028] The drive rotor windings 201 are divided and connected in series for each phase, corresponding to three phases (U-phase, V-phase, W-phase), and are arranged parallel to each other along the circumference, forming part of a circuit 500 described below. In the present embodiment, the drive stator windings 101 are described as distributed windings only by way of example. This is not a limiting characteristic. Rather, the coils can also be lump-wound.

[0029] This allows the electric rotating machine M to generate a torque for rotating the outer rotor 200 by means of the primary excited electromagnetic induction acting on the drive rotor windings 201 of the outer rotor 200, when a three-phase alternating current is supplied from a battery 550, via an inverter 560, which is in Fig. 5 are shown, which are supplied to the drive stator windings 101 of the stator 100.

[0030] As in Fig. As shown in Figure 2, the stator 100 comprises a plurality of stator claw poles 131, 132 made of a soft magnetic material on the inner circumference of the stator base plate 110. These poles serve as magnetic paths, as described below. The stator claw poles 131, 132 are integrally formed with the stator base plate 110 when the stator 100 is cast. The stator 100 has eight claw poles, which form eight matching poles for transferring energy between the stator 100 and the inner rotor 300 in order to induce a current through the inner rotor 300, as described below.

[0031] Each of the stator claw poles 131 comprises a radially extending arm section 131a, which extends radially from one of the two axially spaced edges of the inner circumferential surface of the stator base plate 110 in the direction of the axis, and a radially inwardly directed hand section 131b, which extends axially from the inner end of the radially extending arm section 131a until it is flush with the other edge of the inner circumferential surface of the stator base plate 110 such that, via a gap G2, it is opposite the rotor claw poles 331, 332, 341, 342, 351, 352 of the inner rotor 300 described below.

[0032] Each of the stator claw poles 132 comprises a radially extending arm section 132a, which extends radially from the other of the two axially spaced edges of the inner circumferential surface of the stator base plate 110 in the direction of the axis, and a radially inwardly directed hand section 132b, which extends axially from the inner end of the radially extending arm section 132a until it is flush with one edge of the inner circumferential surface of the stator base plate 110 in such a way that, via a gap G2, it is opposite the rotor claw poles 331, 332, 341, 342, 351, 352 of the inner rotor 300 described below.

[0033] The stator claw poles 131 are arranged circumferentially at regular intervals (for example, at regular intervals of 90 degrees) on the side of the inner circumferential surface. The stator claw poles 132, each arranged between two adjacent stator claw poles 131, are also arranged circumferentially at regular intervals (for example, at regular intervals of 90 degrees) on the side of the inner circumferential surface. In the present embodiment, 8 stator poles are arranged such that they alternately form magnetic poles N and S to provide a pairing between a secondary excited frequency and an induced current forming 8 poles.Thus, the arrangement of the stator claw poles 131 at regular intervals of 90 mechanical degrees and the arrangement of the stator claw poles 132 at regular intervals of 90 mechanical degrees is only an example, and the distances between the stator claw poles can be changed appropriately depending on the number of poles.

[0034] In this structure, the stator claw poles 131, 132 can enclose a continuous space in an intermediate section of the inner circumferential surface of the stator base plate 110 between two axially spaced edges with their radially extending arm sections 131a, 132a and radially inwardly directed hand sections 131b, 132b, and this continuous space can serve for the installation of a single DC-excited stator winding 102 along the inner circumferential surface of the stator base plate 110. In particular, the stator 100 consists of a structure that integrally comprises a first stator and a second stator. The first stator and the second stator can be manufactured separately and then formed in one piece.

[0035] Referring to the Fig. 3. The inner rotor 300 is formed in one piece from a soft magnetic material and comprises cylindrical inner base plates or hubs 310 and a plurality of rotor claw poles 331, 332, 341, 342, 351, 352, which are formed on an outer circumferential surface of the respective associated hub 310 and serve as magnetic paths as described below. According to the present embodiment, the inner rotor 300 has eight claw poles for each of the three phases described below, i.e., a U-phase, a V-phase, and a W-phase, in order to transfer energy pairwise between the inner rotor 300 and the stator 100 to induce a current through the inner rotor 300, as will be described later.

[0036] The inner rotor 300 consists of a three-layer structure comprising an inner rotor 300u for the U-phase, an inner rotor 300v for the V-phase, and an inner rotor 300w for the W-phase, each offset sequentially by 120 electrical degrees along the circumference to accommodate three phases. This inner rotor 300 has rotor claw poles 331, 332 for the U-phase, rotor claw poles 341, 342 for the V-phase, and rotor claw poles 351, 352 for the W-phase, which are integrally formed with the corresponding hubs 310, each assigned to a specific phase and attached to a common shaft for uniform rotation.

[0037] Each of the rotor claw poles 331 or each of the rotor claw poles 341 or each of the rotor claw poles 351 comprises a radially extending spoke section 331a or 341a or 351a extending radially from one of the two axially spaced edges of the outer circumferential surface of the associated hub 310 in the direction of the axis, and a radially outwardly facing edge section 331b or 341b or 351b extending axially from the outer end of the radially extending spoke section 331a or 341a or 351a until it is flush with the other edge of the outer circumferential surface of the associated hub 310 such that it is opposite the radially inwardly facing hand sections 131b, 132b of the stator claw poles 131, 132 of the stator 100 via a gap G2.

[0038] Each of the rotor claw poles 332 or each of the rotor claw poles 342 or each of the rotor claw poles 352 comprises a radially extending spoke section 332a or 342a or 352a extending radially from the other of the two axially spaced edges of the outer circumferential surface of the associated hub 310 in the direction of the axis, and a radially outwardly facing edge section 332b or 342b or 352b extending axially from the outer end of the radially extending spoke section 332a or 342a or 352a until it is flush with one edge of the outer circumferential surface of the associated hub 310 such that it is opposite the radially inwardly facing hand sections 131b, 132b of the stator claw poles 131, 132 of the stator 100 via a gap G2.

[0039] The rotor claw poles 331, 341, or 351 are arranged at regular intervals (for example, at regular intervals of 90 degrees) circumferentially on the side of the outer circumferential surface. The rotor claw poles 332, 342, or 352, each arranged between two adjacent rotor claw poles 331, 341, or 351, are also arranged at regular intervals (for example, at regular intervals of 90 degrees) circumferentially on the side of the outer circumferential surface.

[0040] In this structure, the rotor claw poles 331, 332 or the rotor claw poles 341, 342 or the rotor claw poles 351, 352 can enclose a circumferentially continuous space in an intermediate section of the outer circumferential surface of the associated hub 310 between two axially spaced edges with their radially extending spoke sections 331a, 332a or 341a, 342a or 351a, 352a and radially outwardly facing edge sections 331b, 332b or 341b, 342b or 351b, 352b, and this continuous space can serve for the installation of a single AC induction rotor winding 301u or 301v or 301w along the outer circumferential surface of the associated hub 310.

[0041] The AC induction rotor windings 301u, 301v and 301w for the three phases, i.e. the U-phase, the V-phase and the W-phase of the inner rotor 300, are, as shown in Fig. 4 shown, connected via connecting cables (wiring) 309u, 309v and 309w to drive rotor windings 201, i.e. 201u, 201v and 201w.

[0042] The DC-excited coil 102 of the stator 100 is connected together with the drive stator windings 101 (101u, 101v, 101w) on the stator 100, the drive rotor windings 201 (201u, 201v, 201w) of the outer rotor 200 and the AC induction rotor windings 301 (301u, 301v, 301w) of the inner rotor 300 in a Fig. 5 shown circuit 500 installed.

[0043] In circuit 500, the drive stator windings 101 (101u, 101v, 101w) are connected via a diode bridge 510 to the DC-excited stator winding 102 on the stator 100. The AC input to the drive stator windings 101 is rectified by the diode bridge 510 in order to output a DC current to the DC-excited stator winding 102.

[0044] Furthermore, in circuit 500, the DC excited stator winding 102 of the stator 100 and the AC induction rotor windings 301u, 301v, 301w are electromagnetically coupled via the stator claw poles 131, 132 and rotor claw poles 331, 332, 341, 342, 351, 352, so that they supply the drive rotor windings 201 (201u, 201v, 201w) of the outer rotor 200 with the DC current supplied to the DC excited stator winding 102 via the stator claw poles 131, 132 of the stator 100 and via the rotor claw poles 331, 332, 341, 342, 351, 352 of the inner rotor 300. of the stator 100 is supplied.

[0045] In particular, the circuit 500, by means of a battery 550 and an inverter 560, allows the formation of an alternating current in order to extract the energy stored in the battery 550 as alternating current via the inverter 560, and causes a rotation of the electrical rotating machine M with a desired torque by controlling the inverter 560 via a control unit 570.

[0046] In this case, in the electrical rotating machine M, a torque is generated by the interaction between the magnetic flux generated at the drive stator windings 101 (101u, 101v, 101w) of the stator 100 and the magnetic field generated at the drive rotor windings 201 (201u, 201v, 201w) of the outer rotor 200, by using a primary excitation, i.e., an electromagnetic induction that induces a current per phase through the drive rotor windings 201 (201u, 201v, 201w) of the outer rotor 200, by coupling a rotating field generated by the supply of energy (or current) to the drive stator windings 101 (101u, 101v, 101w) of the stator 100 via the circuit 500 with the drive rotor windings 201. generated to drive the outer rotor 200.

[0047] The circuit 500 has a circuit structure in which the diode bridge 510 is coupled to a section of a neutral point of a Y-shaped connection of the drive stator windings 101 (101u, 101v, 101w) of the stator 100, each of which is connected to phases (U-phase, V-phase, W-phase) of the inverter 560, via which the DC excited stator winding 102 of the stator 100 and the diode bridge 510 are connected in parallel.

[0048] By connecting a group of U-phase stator windings 101u connected in series, a group of V-phase stator windings 101v connected in series and a group of W-phase stator windings 101w connected in series, which form the drive stator windings 101, the inverter 560 can perform a DC / AC conversion of a direct current stored in the battery 550 into an alternating current in order to excite the stator windings in each phase with the alternating current.

[0049] The diode bridge 510 has a circuit structure comprising a first pair of rectifier diodes (rectifier elements) 511u, 512u; a second pair of rectifier diodes 511v, 512v; and a third pair of rectifier elements 511w, 512w, wherein the rectifier diodes of each pair are connected in series and the pairs are connected in parallel to rectify the current of each phase in the same direction.

[0050] The diode bridge 510 is formed by an intermediate section between the rectifier diodes of each pair, i.e., the first pair of rectifier diodes 511u, 512u; the second pair of rectifier diodes 511v, 512v; and the third pair of rectifier elements 511w, 512w, with one end of the associated group of U-phase stator windings 101u, V-phase stator windings 101v and W-phase stator windings 101w, which is opposite the end connected to the inverter 560. Furthermore, the diode bridge 510 is formed by connecting the DC excited stator winding 102 to the stator 100 and each pair of rectifier diodes 511u, 512u, rectifier diodes 511v, 512v and rectifier diodes 511w, 512w in parallel, with both ends of each pair serving as a common connection point.

[0051] This circuit structure makes it possible to convert the direct current stored in the battery 550 into alternating current in the inverter 560, to excite each phase of the drive stator windings 101 (101u, 101v, 101w) with alternating current, to rectify the alternating current that has flowed through each phase of the drive stator windings 101 (101u, 101v, 101w) through the corresponding phase of the pair of rectifier diodes 511u, 512u, the pair of rectifier diodes 511v, 512v and the pair of rectifier diodes 512w, 512v of the diode bridge 510 into direct current, and to supply the direct current to the coil 102 of the stator 100 excited with direct current.

[0052] The electric rotating machine M is designed such that magnetic circuits are formed on the basis of the stator claw poles 131, 132, using the stator hub 110 as a yoke, in order to provide a bypass path for lines of a magnetic flux of the magnetic field which is generated by a circular current through the DC-excited coil 102, i.e. in other words along the stator hub 110, while the DC current generated by the rectification of the driving AC current is supplied via the diode bridge 510 to the DC-excited stator winding 102 on the stator 100.

[0053] The radially inwardly facing circumferences 131b, 132b of the stator claw poles 131, 132 come periodically or repeatedly, with only a tiny gap G2, very close to the outwardly facing edge sections 331b, 332b, 341b, 342b, 351b, 352b of the rotor claw poles 331, 332, 341, 342, 351, 352.

[0054] As a result, the magnetic flux flowing through the stator claw poles 131, 132 flows through the radially extending spoke sections 131a of the stator hub 110 and through the radially extending spoke sections 132a of the stator hub 110 in directions that depend on the magnetic field generated by the circular current through the DC-excited stator winding 102, and the magnetic flux couples with the inner rotor 300, so that it flows from the radially inwardly facing circumferences 131b, 132b of the stator claw poles 131, 132 to radially outwardly facing edge sections 331b, 332b, 341b, 342b, 351b, 352b of the rotor claw poles 331, 332, 341, 342, 351, 352 of the inner rotor 300 is transmitted when these approach the radially inwardly directed circumferences 131b, 132b.

[0055] This creates magnetic circuits that run through radially outwardly facing edge sections 331b, 332b, 341b, 342b, 351b, 352b and radially extending spoke sections 331a, 332a, 341a, 342a, 351a, 352a of the inner rotor 300 and guide them back via a hub or inner base plate 310 of the inner rotor 300 as a yoke to the stator claw poles 131, 132 of the stator 100 and allow the coupled magnetic flux to pass through in directions that depend on the magnetic fields generated by the circular current through the DC-excited coil 102.

[0056] In other words, the stator claw poles 131, 132 and rotor claw poles 331, 332, 341, 342, 351, 352 of the inner rotor 300 are designed according to the lines of magnetic flux of the magnetic fields formed around the DC excited stator winding 102 and the AC induction rotor windings 301 (301u, 301v, 301w) to serve as magnetic paths that allow the magnetic fluxes to pass through.

[0057] Since the magnetic circuits are formed by using the hub 310 as a yoke for the magnetic fluxes flowing through the rotor claw poles 331, 332, 341, 342, 351, 352 of the inner rotor 300, the electric rotating machine M can use a secondary excitation, i.e., electromagnetic induction, by which currents are induced in the AC induction rotor windings 301u, 301v, 301w surrounded by rotor claw poles 331, 332, 341, 342, 351, 352.

[0058] The currents induced in the AC induction rotor windings 301u, 301v, 301w can have three AC waveforms corresponding to a U-phase, a V-phase and a W-phase, so that they can be provided (or supplied) as AC input currents to the drive rotor coils 201u, 201v, 201w of the outer rotor 200, since the rotor claw poles 331, 332 surrounding the rotor coil 301u; the rotor claws 341, 342 surrounding the rotor coil 301v; and the rotor claw poles 351, 352 surrounding the rotor coil 301w overlap each other, but are offset circumferentially by 120 electrical degrees by alternately reversing the direction of the magnetic flux circumferentially.

[0059] Consequently, the outer rotor 200, which is formed in one piece with a shaft for uniform rotation, is driven not only by a torque generated by a primary excitation in which magnetic fluxes generated at the drive stator windings 101 of the stator 100 couple with the drive rotor windings 201 to generate a magnetic field, but also by a torque achieved by amplifying an interaction with the magnetic fluxes generated by the drive stator windings 101 of the stator 100 by supplying induced alternating currents, generated by a secondary excitation in AC induction coils 301 (301u, 301v, 301w), to the drive rotor windings 201.

[0060] The preceding description clearly shows that in an electrical rotating machine M according to the present embodiment, a structure is used in which a DC excited stator winding 102 and stator claw poles 131, 132 are located on the side of an inner circumference of a stator 100, which is received inside an outer rotor 200, and in which an inner rotor 300, comprising rotor claw poles 331, 332, 341, 342, 351, 352 and AC induction rotor windings 301 (301u, 301v, 301w), is rotatably received inside the stator 100.

[0061] This enables not only the generation of torque through primary excitation by electromagnetic induction between the stator 100 and the outer rotor 200, but also the increase of torque by supplying the outer rotor 200 with alternating current generated by secondary excitation by electromagnetic induction between the stator 100 and the inner rotor 300, simply by supplying the drive stator windings 101 (101u, 101v, 101w) of the stator 100 with a drive alternating current from an energy source installed in the vehicle, i.e. the battery 500 and the inverter 560.

[0062] Thus, an electrically rotating machine M with secondary excited induction is provided by carrying out a secondary excitation that does not require a slip ring and a plurality of inverters.

[0063] Although embodiments of the present invention have been described, it is obvious to the person skilled in the art that modifications can be made without departing from the scope of the present invention. All such modifications and equivalents are to be considered as covered by the following claims. [List of reference symbols] 100 Stator (first stator, second stator) 101 Drive stator winding 102 DC excited stator winding 120 stator teeth 131, 132 Stator claw poles 200 outer rotor (first rotor) 201 Drive rotor winding 220 rotor teeth 300 inner rotor (second rotor) 301 AC induction rotor coil 309u, 309v, 309w connection cable (wiring) 331, 332, 341, 342, 351, 352 Rotor claw poles 500 circuit 510 diode bridge 511u, 511v, 511w, 512u, 512v, 512w rectifier diode 550 battery 560 inverters 570 Control unit G1, G2 gap M rotating electric machine

Claims

[1] Electric rotating machine (M) with one axis, comprising: a first stator (100) which has drive stator windings (101) which generate a stator-side magnetic flux when supplied with alternating current; a first rotor (200) which accommodates the first stator (100) to surround an outer circumferential surface (120a) of the first stator (100), and which has drive rotor windings (201) with which the stator-side magnetic flux generated by the drive stator windings (101) couples, and which is rotated due to the generation of a torque between the rotor-side magnetic flux generated by the drive rotor windings (201) and the stator-side magnetic flux; a second stator (100) which is arranged closer to the axis than to an inner circumferential surface of the first stator (100) and is surrounded by the inner circumferential surface, wherein the second stator (100) has a DC-excited stator winding (102) which generates a magnetic flux when supplied with a DC current generated by converting the AC current supplied to the drive stator windings (101); and a second rotor (300) which is arranged closer to the axis than the second stator (100) and is surrounded by the inner circumferential surface, wherein the second rotor (300) has AC induction rotor windings (301) which induce an alternating current by means of the magnetic field generated by the DC excited stator winding (102) of the second stator (100), wherein the first stator (100), the first rotor (200), the second stator (100) and the second rotor (300) are aligned coaxially along the axis, and wherein the alternating current induced by the AC induction rotor windings (301) of the second rotor (300) is supplied to the drive rotor windings (201) of the first rotor (200). [2] Electric rotating machine (M) according to claim 1, further comprising: a diode bridge (510) which is configured to convert the alternating current supplied to the drive stator windings (101) of the first stator (100) into direct current. [3] Electric rotating machine (M) according to claim 1 or 2, further comprising: Wiring (309u, 309v, 309w) designed to supply the alternating current induced by the AC induction rotor windings (301) of the second rotor (300) to the drive rotor windings (201) of the first rotor (200). [4] Electric rotating machine (M) according to any one of claims 1 to 3, wherein the second stator (100) comprises stator claw poles (131, 132) which serve as magnetic paths for the magnetic flux induced by the DC excited stator winding (102); the second rotor (300) comprises rotor claw poles (331, 332, 341, 342, 351, 352) which serve as magnetic paths for the magnetic flux coming in from the stator claw poles (131, 132); and the rotor claw poles (331, 332, 341, 342, 351, 352) are arranged to induce an alternating current through the alternating current induction rotor windings (301) by electromagnetic induction, which is caused by the magnetic field generated by the magnetic flux. [5] Electric rotating machine (M) according to claim 4, wherein the DC excited stator winding (102) of the second stator (100) and the AC induction rotor windings (301) of the second rotor (300) are arranged circularly around a common axis of rotation of the second stator (100) and the second rotor (300); and the stator claw poles (131, 132) of the second stator (100) and the rotor claw poles (331, 332, 341, 342, 351, 352) of the second rotor (300) are arranged along magnetic flux lines formed by the DC excited stator winding (102) and the AC induction rotor windings (301) so that electromagnetic induction takes place during periodically repeated approaches during the relative rotation.

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