JP2013243831A - Transverse flux machinery - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide flux control transverse flux machinery (TFMA) having a simple structure.SOLUTION: In a plurality of stator blocks stacked in the axial direction with a phase difference so as to form three-phase, ring-like secondary phase windings 6U, 6V, 6W wound in ring-like slots between the right teeth and left teeth of each rotor core are inserted. When an AC magnetic field supplied from a stator core interlinks each secondary phase winding 6U, 6V, 6W, a secondary phase voltage is induced in each secondary phase winding 6U, 6V, 6W, but since the secondary phase voltages of respective phases are connected in series and rectified collectively by means of a diode 903, a field flux of the same magnitude can be generated in the stator block of each phase.

Description

The present invention relates to a transverse flux machine (TFMA). More particularly, the present invention relates to a transverse flux machine device having a core formed of laminated iron plates.

Transverse flux machines (TFMs) with a large number of poles and short current paths are attractive electric machines because of their high torque / weight ratio, high power / weight ratio and low copper loss. US Pat. No. 7,830,057 proposes the tandem TFM shown in FIG. This TFM is made up of a number of divided core pieces. However, the split core structure causes an increase in magnetoresistance and a decrease in robustness. FIG. 2 shows another prior TFM that uses a core made from Soft Magnetic Composites (SMC). However, the magnetic properties and robustness of the SMC core are not sufficient.

Electric vehicles and wind turbines are eagerly awaiting direct drive machines (DDM) that can reduce gear losses and inertial mass. Transverse flux machines (TFMs) are ideal for DDMs that generate large torques at low speeds. However, the DDM configured by the permanent magnet rotor TFM (TFPM) shown in FIGS. 1 and 2 requires a large number of permanent magnets. As a result, TFPM-DDM is very expensive. Furthermore, TFPM-DDM has the disadvantages that it is difficult to control the magnetic flux and that the field weakening loss is large in the high speed region.

US Pat. No. 7,830,057

One object of the present invention is to provide a flux controlled transverse flux machine (TFMA) having a simple structure. Another object of the present invention is to provide a magnetic flux control type transverse magnetic flux machine (TFMA) having a simple core structure using laminated iron plates.

The features of the present invention are described below by taking a transverse flux machine (TFM) having a ring-shaped stator coil as an example. In the first aspect of the present invention, a plurality of transverse magnetic flux machines (TFMs) arranged in parallel have a ring-shaped secondary phase winding wound in a ring-shaped slot between the left and right teeth of the rotor core. Each has a line. Each secondary phase winding connected in series constitutes a field magnetic flux generation circuit by being short-circuited through a diode.

Preferably, the U-phase secondary phase winding wound around the U-phase rotor core, the V-phase secondary phase winding wound around the V-phase rotor core, and the W-phase secondary phase winding wound around the W-phase rotor core The wires are connected in series and are shorted by a diode. A secondary phase voltage is induced in the secondary phase winding by passing an exciting current through each winding wound around the stator core of each phase. The secondary phase voltage includes a synchronous phase voltage component corresponding to the rotational angular velocity of the rotor and an asynchronous phase voltage component. This asynchronous phase voltage component includes a harmonic component of the synchronous phase voltage component. The sum of the secondary phase voltages of each phase is rectified by the diode. The sum of the synchronous phase voltage components included in each secondary phase voltage is zero. Therefore, the sum of the asynchronous phase voltage components rectified by the diode causes a field current to flow in each secondary phase winding. As a result, the copper loss of the secondary phase winding is reduced and the field current ripple is also reduced. Furthermore, since this secondary phase winding does not have a coil end, copper loss is reduced.

By supplying an asynchronous frequency current to the primary phase winding, an asynchronous phase voltage component is induced in the secondary phase winding. Further, since the sine wave voltage applied to the primary phase winding is modulated by the non-linearity of the magnetic circuit and the change of the magnetic resistance, the secondary phase voltage includes an asynchronous phase voltage component. In addition, by supplying an asynchronous frequency current to an independent excitation phase winding wound around the stator core, an asynchronous phase voltage component is induced in the secondary phase winding.

According to a preferred embodiment, a three-phase inverter applies a three-phase voltage to three single-phase windings connected in a star shape. The neutral point to which one end of the three single-phase windings is connected is connected to the DC link line through the excitation current control transistor. As a result, the asynchronous phase voltage component is easily induced in the secondary phase winding.

According to a preferred embodiment, each pair of single phase winding and excitation phase winding is wound around each stator core. The single-phase inverter supplies a primary excitation current of a predetermined frequency to each excitation phase winding connected in series with each other. As a result, the asynchronous phase voltage component is easily induced in the secondary phase winding.

According to a preferred embodiment, the moving core and the stator core are constituted by a centipede-shaped core formed of laminated steel sheets. As a result, a simple TFM core can be configured. The transverse flux machine (TFMA) of the present invention can employ a transverse flux machine having a conventional core structure.

FIG. 1 is an axial cross-sectional view showing a conventional TFM having a split core. FIG. 2 is a schematic cross-sectional view of a conventional TFM having an SMC core. FIG. 3 is an axial cross-sectional view showing a transverse flux machine (TFMA) having a three-phase wound rotor transverse flux machine (TFWRM) arranged in tandem. FIG. 4 is an axial cross-sectional view showing only the three wound rotor transverse flux machines (TFWRM) shown in FIG. FIG. 5 is a partial side view showing the stator core shown in FIG. 6 is a partial plan view of the stator core shown in FIG. FIG. 7 is a circumferential development view showing the arrangement of the rotor teeth shown in FIG. FIG. 8 is a circumferential development view showing the arrangement of the rotor teeth shown in FIG. FIG. 9 is a circumferential development view showing an arrangement of the stator teeth shown in FIG. FIG. 10 is a circumferential development showing the relative positions of the rotor teeth and the stator teeth at an electrical angle of 0 degrees. FIG. 11 is a circumferential development view showing the relative positions of the rotor teeth and the stator teeth at an electrical angle of 90 degrees. FIG. 12 is a circumferential development view showing the relative positions of the rotor teeth and the stator teeth at an electrical angle of 180 degrees. FIG. 13 is a circumferential development view showing the relative positions of the rotor teeth and the stator teeth at an electrical angle of 270 degrees. FIG. 14 is a circuit diagram showing an example of a circuit for flowing a field current. FIG. 15 is a circuit diagram showing another circuit example for flowing a field current.

A wound rotor type transverse flux machine (TFWRM) with a centipede core will be described with reference to FIGS. The TFMA shown in FIGS. 3 and 4 has three single-phase TFWRMs arranged in tandem in the axial direction. The U-phase TFWRM has a U-phase stator core 2U and a U-phase rotor core 4U. V-phase TFWRM has V-phase stator core 2V and V-phase rotor core 4V. The W-phase TFWRM has a W-phase stator core 2W and a W-phase rotor core 4W. Stator cores 2U, 2V and 2W arranged in tandem in the axial direction are fixed to nonmagnetic stator housing 100.

A ring-shaped U-phase winding 3U is wound around the U-phase stator core 2U. A ring-shaped V-phase winding 3V is wound around the V-phase stator core 2V. A ring-shaped W-phase winding 3W is wound around the W-phase stator core 2W. The stator cores 2U, 2V and 2W are each formed in a ring shape. Each of the ring-shaped phase windings 3U-3W is accommodated in a space between the left stator teeth 21L and the right stator teeth 21R.

The U-phase rotor core 4U, the V-phase rotor core 4V and the W-phase rotor core 4W arranged in tandem in the axial direction are fixed to a nonmagnetic rotor housing 200 fixed to the rotor shaft 201. The rotor shaft 201 is held by the stator housing 100 via a bearing. A ring-shaped U-phase secondary phase winding 6U is wound around the U-phase rotor core 4U. A ring-shaped V-phase secondary phase winding 6V is wound around the V-phase rotor core 4V. A ring-shaped W-phase secondary phase winding 6W is wound around the W-phase rotor core 4W. The rotor cores 4U, 4V and 4W are each formed in a ring shape. Each of the ring-shaped secondary phase windings 6U-6W is accommodated in a space between the left rotor teeth 41L and the right rotor teeth 41R. A cooling air flow (C.A.) flowing through the inlet and outlet formed in the stator housing 100 and the rotor housing 200 cools each stator core 2U-2W and each rotor core 4U-4W.

A U-phase stator having a U-phase stator core 2U and a U-phase winding 3U will be described with reference to FIGS. The V-phase stator and the W-phase stator have essentially the same structure as the U-phase stator. The stator core 2U includes a left stator tooth 21L, a right stator tooth 21R, an annular yoke portion 24, a left oblique portion 25L, and a right oblique portion 25R. The stator teeth 21L and 21R protrude inward in the radial direction RA. The annular yoke portion 24 extends in the circumferential direction PH. The left stator teeth 21L, the right stator teeth 21R, the left oblique portion 25L, and the right oblique portion 25R are each arranged in the circumferential direction PH.

Each left diagonal portion 25L connects each left stator tooth 21L and the yoke portion 24. Each right oblique portion 25R connects each right stator tooth 21R and the yoke portion 24. The left oblique portion 25L extends obliquely forward from the yoke portion 24. The right oblique portion 25R extends obliquely backward from the yoke portion 24. The left stator teeth 21L and the right stator teeth 21R are adjacent to each other in the axial direction AX across the U-phase winding 3U accommodated in the annular slot of the U-phase core 2U.

As shown in FIG. 5, the stator core 2U is composed of six soft iron plates 7 laminated in the axial direction. Each plate 7 includes a left tooth 71L, a right tooth 71R, an annular yoke portion 74, a left oblique portion 75L, and a right oblique portion 75R. The left teeth 71L and the right teeth 71R protrude inward in the radial direction RA. The yoke portion 74 extends in the circumferential direction PH. Each left oblique portion 75L extending obliquely connects each left tooth 71L and the yoke portion 74. Each diagonally right portion 75R extending diagonally connects each right tooth 71R and the yoke portion 74. Therefore, the stator core 2U is composed of a plurality of soft iron plates 7 stacked in the axial direction. The left oblique portion 75L extending straight in the oblique direction is formed by pressing a flat iron plate. The right oblique portion 75R formed by pressing a flat iron plate extends straight in the oblique direction.

The spirally laminated soft iron plates can be used in place of the plurality of soft iron plates 7 laminated in the axial direction. It can be seen that each annular gap 74g is formed between each pair of yoke portions 74 adjacent to each other. Similarly, each tooth-shaped gap 71g is formed between each pair of left teeth adjacent to each other in the axial direction AX. Similarly, each tooth-shaped gap 71g is formed between each pair of right teeth 71R adjacent to each other in the axial direction AX. Each gap 74g, 71g is filled with each resin layer containing soft iron powder. The resin layer reduces the harmonic component of iron loss. Instead of using the resin layer, the yoke portion 74 and the teeth 71L and 71R can be curved, bent or protruded in the axial direction AX to reduce magnetic vibration. After all, the stator core 2U is made by an axial lamination process of a plurality of soft iron plates 7.

FIG. 6 is a partial side view schematically showing a part of the stator core 2U. FIG. 7 is a partial plan view schematically showing a part of the stator core 2U. The left stator teeth 21L and the right stator teeth 21R are alternately arranged in the circumferential direction PH. The two left stator teeth 21L are adjacent to each other across a space having a circumferential width substantially equal to one stator tooth. Similarly, the two right stator teeth 21R are adjacent to each other across a space having a circumferential width substantially equal to the one stator teeth 21R. The left oblique part 25L and the right oblique part 25R are alternately arranged in the circumferential direction PH. The two left oblique portions 25L are adjacent to each other across a space having a circumferential width substantially equal to the oblique portion 25L. Similarly, the two right diagonal portions 25R are adjacent to each other across a space having a circumferential width substantially equal to the diagonal portion 25R.

Each rotor core 4U-4W has essentially the same structure as the stator core 2U. The left rotor teeth 41L, the right rotor teeth 41R, the annular yoke portion 44, the left oblique portion 45L, and the right oblique portion 45R. The left rotor teeth 41L and the right rotor teeth 41R protrude radially outward. The yoke portion 44 extends in the circumferential direction PH. The left rotor teeth 41L, the right rotor teeth 41R, the left oblique portion 45L, and the right oblique portion 45R are each arranged in the circumferential direction PH. Each left oblique portion 45L connects each left rotor tooth 41L and the yoke portion 44. Each right oblique portion 45R connects each right rotor tooth 41R and the yoke portion 44. The left oblique portion 45L extends obliquely forward from the yoke portion 44. The right oblique portion 45R extends obliquely backward from the yoke portion 44. The left rotor teeth 41L face the stator teeth 21L in the radial direction RA. The right rotor teeth 41R faces the right stator teeth 21R in the radial direction RA.

Stator teeth 21L of stator core 2U and rotor teeth 41L of rotor core 4U have a U-phase electrical angle. Stator teeth 21L of stator core 2V and rotor teeth 41L of rotor core 4V have a V-phase electrical angle. Stator teeth 21L of stator core 2W and rotor teeth 41L of rotor core 4W have a W-phase electrical angle. Each angle between each of these three electrical angles is 120 degrees. After all, the TFMA shown in FIG. 3 has three single phase transverse flux wound rotor machines (TFWRM). FIG. 8 is a circumferential partial development view showing one arrangement of the rotor teeth 41L and 41R. FIG. 9 is a circumferential partial development view showing one arrangement of the stator teeth 21L and 21R.

The operation of the U-phase TFWRM will be described with reference to FIGS. The left stator teeth 21L of the U-phase stator core 2U and the left rotor teeth 41L of the U-phase rotor core 4U are shown. The right stator teeth 21R of the U-phase stator core 2U and the right rotor teeth 41R of the U-phase rotor core 4U are not shown in FIGS.

FIG. 10 shows the position of the left rotor teeth 41L at an electrical angle of 0 degrees. FIG. 11 shows the position of the rotor teeth at an electrical angle of 90 degrees. FIG. 12 shows the position of the rotor teeth at an electrical angle of 180 degrees. FIG. 11 shows the position of the rotor teeth at an electrical angle of 270 degrees. Due to the field current If flowing in the U-phase secondary phase winding 6U, the left rotor tooth 41L becomes the N pole, and the right rotor tooth 41R (not shown) becomes the S pole. The U-phase rotor core 4U moves in the right direction.

In FIG. 10, the rotor teeth 41L are located between two adjacent stator teeth 21L. Next, the first half-wave component of the U-phase current is passed through the U-phase secondary winding 6U. As a result, as shown in FIG. 11, the stator teeth 21L of the U-phase stator core 2U become the S pole, and the stator teeth 21L pulls the rotor teeth 41L to the right. Next, as shown in FIG. 12, the rotor teeth 41L reach a position directly below the stator teeth 21L. Thereafter, the U-phase current is inverted, and the second half-wave component of the U-phase current is passed through the U-phase secondary phase winding 6U. As a result, as shown in FIG. 13, the stator teeth 21L of the U-phase stator core 2U become N poles, so that the rotor teeth 41L are repelled in the right direction.

The motor drive circuit 9 of the first embodiment will be described with reference to FIG. The motor drive circuit 9 that drives the three-phase transverse flux wound rotor motor has an inverter 901 and an excitation current control transistor 902. The U-phase leg of the inverter 901 has an upper transistor UH and a lower transistor UL. The V-phase leg of the inverter 901 has an upper transistor VH and a lower transistor VL. The W-phase leg of the three-phase inverter 901 has an upper transistor WH and a lower transistor WL.

One end of the U-phase winding 3U, V-phase winding 3V and W-phase winding 3W connected in a star shape is connected to the neutral point N. The neutral point N is connected to the low potential DC link line 2000 through the exciting current control transistor 902. The other ends of the three-phase windings 3U-3W are individually connected to the output ends of the legs of the inverter 901. The U-phase secondary phase winding 6U, the V-phase secondary phase winding 6V, and the W-phase secondary phase winding 6W connected in series are short-circuited through a diode 903. Secondary phase winding 6U-6W and diode 903 constitute a rotor circuit. The controller 910 controls the inverter 901 and the excitation current control transistor 902.

The operation of the motor drive circuit 9 will be described. The inverter 901 supplies a three-phase sine wave current to the three-phase winding 3U-3W. U-phase current Iu is supplied to U-phase winding 3U. V-phase current Iv is supplied to V-phase winding 3V. W-phase current Iw is supplied to W-phase winding 3W. When the excitation current control transistor 902 is turned on, the primary excitation current If0 flows from the upper transistors UH, VH, and WH to the excitation current control transistor 902 through the phase windings 3U, 3V, and 3H.

A U-phase secondary voltage Vu is induced in the secondary phase winding 6U. A V-phase secondary voltage Vv is induced in the secondary phase winding 6V. A W-phase secondary voltage Vw is induced in the secondary phase winding 6W. The sum of the three secondary voltages Vu, Vv, Vw is rectified by a diode 903 fixed to the rotor core. As a result, a field current If flows through the secondary phase winding 6U-6W. The field current If is hardly influenced by the three-phase sine wave currents Iu, Iv, and Iw supplied from the inverter 901. By switching the exciting current control transistor 902, a primary exciting current If0 having a predetermined frequency is formed. The field current If flows in accordance with the primary excitation current If0.

A second exciting current control transistor for connecting the high potential side DC link line 1000 and the neutral point N instead of the exciting current control transistor 902 for connecting the high potential side DC link line 200 and the neutral point N. May be adopted. Alternatively, both the exciting current control transistor 902 and the second exciting current control transistor 902 may be employed.

A transverse flux machine device (TFMA) having a three-phase winding rotor transverse flux machine (TFWRM) of the second embodiment will be described with reference to FIG. FIG. 15 shows a motor drive circuit of this transverse magnetic flux machine (TFMA). In this embodiment, a ring-shaped U-phase excitation phase winding 30U is wound in a space between the left stator teeth 21L and the right stator teeth 21R of the U-phase stator core 2U. Ring-shaped V-phase excitation phase winding 30V is wound in the space between left stator teeth 21L and right stator teeth 21R of V-phase stator core 2V. Ring-shaped W-phase excitation phase winding 30W is wound in a space between left stator teeth 21L and right stator teeth 21R of W-phase stator core 2W.

The motor drive circuit 9 includes a three-phase full-wave diode rectifier 901A having six diodes D and a single-phase inverter 904. For example, the single-phase inverter 904 is configured by a full bridge having four transistors. Single-phase inverter 904 applies a single-phase AC voltage having a predetermined frequency to three exciting phase windings 30U-30W connected in series with each other. One end of the U-phase winding 3U, V-phase winding 3V and W-phase winding 3W connected in a star shape is connected to the neutral point N. The other ends of the three-phase windings 3U-3W are individually connected to the input ends of the legs of the rectifier 901A. The U-phase secondary phase winding 6U, the V-phase secondary phase winding 6V, and the W-phase secondary phase winding 6W connected in series are short-circuited through a diode 903. Secondary phase winding 6U-6W and diode 903 constitute a rotor circuit. The controller 910 controls the single phase inverter 904.

When an excitation current Ifo having a predetermined frequency is supplied to the three excitation phase windings 30U-30W, an AC secondary voltage having a predetermined frequency is induced in the secondary phase windings 6U-6W. Since this AC secondary voltage is rectified by the diode 903, the field current If flows through the three secondary phase windings 6U-6W. When the rotor is rotating, the U-phase voltage Vu is induced in the phase winding 3U, the V-phase voltage Vv is induced in the phase winding 3V, and the W-phase voltage Vw is induced in the phase winding 3W. The three phase voltages Vu-Vw are rectified and output by the rectifier 901A. The three-phase current flowing through the three phase windings 3U-3W has little effect on the sum of the secondary phase voltages induced in the secondary phase windings 6U-6W.

When the transverse magnetic flux machine (TFMA) is driven by a motor, a three-phase inverter is employed instead of the three-phase full-wave diode rectifier 901A shown in FIG.

For example, an exciting current control transistor can be employed instead of the single-phase inverter 904 shown in FIG. 15 when starting a transverse flux machine (TFMA) is not required, such as an alternator. This exciting current control transistor performs switching control of the direct current supplied from the direct current power source to the exciting phase windings 30U-30W. However, when the rotor core 4U-4W rotates at a high speed, the exciting current control transistor can supply a direct current to the exciting phase windings 30U-30W. The left rotor teeth 21L and the right rotor teeth 21R rotate at high speed, and the left stator teeth 21L and the right stator teeth 21R are DC magnetized by this DC current, so that the secondary AC voltage is induced in the secondary phase winding 6U-6W. Is done.

When the transverse flux machine (TFMA) rotates at high speed, the single-phase inverter 904 can supply a direct current to the excitation phase windings 30U-30W. Thereby, the switching loss of the single phase inverter 904 can be reduced, and the iron loss can be reduced.

Claims (6)

A single coil wound in a space extending between the left teeth (21L) and the right teeth (21R) of the stator core (2U-2W) facing the movable core (4U-4W) movable in the movement direction (PH). In a transverse flux machine (TFMA) comprising a plurality of transverse flux machines (TFM) each having a phase winding (3U-3W),
The moving core (4U-4W) of each transverse flux machine (TFM) includes a left tooth (41L) that can face the left tooth (21L) of the stator core (2U-2W) and a right tooth (21U-2W) of the stator core (2U-2W). 41R) has a right tooth (41R) capable of facing, and a yoke (44) for magnetically connecting the left tooth (41L) and the right tooth (41R),
Each transverse flux machine (TFM) has a secondary phase winding (6U-6W) wound in a space extending between the left teeth (41L) and the right teeth (41R) of the moving core (4U-4W). Each with
Each secondary phase winding (6U-6W) connected in series constitutes a circuit for generating a field magnetic flux by being short-circuited through a diode, thereby forming a transverse magnetic flux machine (TFMA). The plurality of transverse flux machines (TFMs) include a U-phase moving core (4U) having a U-phase winding (3U), a V-phase moving core (4V) having a V-phase winding (3V), and a W-phase winding ( 3W) with a W phase transfer core (4W)
The transverse magnetic flux according to claim 1, wherein the neutral point (N) of each phase winding (3U-3W) fed from the three-phase inverter is connected to the DC link line through an exciting current control transistor (902). Mechanical equipment (TFMA).   Each transverse flux machine (TFM) has an exciting phase winding (30U-30W) wound in a space between a left tooth (21L) and a right tooth (21R) of a stator core (2U-2W), respectively. The transverse magnetic flux machine (TFMA) according to 1. The plurality of transverse flux machines (TFMs) include a U-phase moving core (4U) having a U-phase winding (3U), a V-phase moving core (4V) having a V-phase winding (3V), and a W-phase winding ( 3W) with a W phase transfer core (4W)
The transverse magnetic flux machine (TFMA) according to claim 3, wherein each of the exciting phase windings (30U-30W) connected in series is applied with an alternating current. The plurality of transverse flux machines (TFMs) include a U-phase moving core (4U) having a U-phase winding (3U), a V-phase moving core (4V) having a V-phase winding (3V), and a W-phase winding ( 3W) with a W phase transfer core (4W)
The plurality of transverse flux machines (TFMs) are rotating,
The transverse magnetic flux machine (TFMA) according to claim 3, wherein each of the exciting phase windings (30U-30W) connected in series is applied with a direct current. The core (2U-2W, 4U-4W) includes a yoke part (24, 44) extending in the moving direction of the moving core (4U-4W) and an oblique part (25L, 45L, 25R, 45R)
The oblique portions (25L, 45L, 25L, 45R) magnetically connect the teeth (21L, 41L, 21R, 41R) to the yoke portions (24, 44),
The transverse magnetic flux machine according to claim 1, wherein the yoke portion (24, 44), the oblique portion (25L, 45L, 25R, 45R) and the tooth (21L, 41L, 21R, 41R) are formed essentially of laminated iron plates. apparatus.

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