阅读说明：本技术 旋转电机 (Rotating electrical machine ) 是由 宇贺治元 吉川祐一 平田胜弘 新口昇 于 2018-07-25 设计创作，主要内容包括：从径向内侧开始将第一转子、沿周向具有多个磁极片和绕组的固定部以及第二转子以彼此隔开间隙的方式同轴配置,第一转子和第二转子由永久磁体或电磁体构成,绕组用于在第一转子和第二转子处产生电磁力转矩,电磁力转矩通过第一转子的旋转磁传递到第二转子,或者通过第二转子的旋转磁传递到第一转子,在第一转子和第二转子中的任意一方的转子处,电磁力转矩与通过另一方的转子磁传递的转矩重叠。(The first rotor, the fixed portion having a plurality of magnetic pole pieces and a winding in a circumferential direction, and the second rotor are coaxially arranged with a gap from a radially inner side, the first rotor and the second rotor are formed of permanent magnets or electromagnets, the winding is configured to generate electromagnetic force torque at the first rotor and the second rotor, the electromagnetic force torque is magnetically transmitted to the second rotor by rotation of the first rotor or is magnetically transmitted to the first rotor by rotation of the second rotor, and the electromagnetic force torque overlaps torque magnetically transmitted by the other rotor at one of the first rotor and the second rotor.)

1. A kind of electric rotating machine is disclosed,

the first rotor, the fixed part having a plurality of magnetic pole pieces and windings in the circumferential direction, and the second rotor are coaxially arranged with a gap from the radially inner side,

the first rotor and the second rotor are composed of a magnetic material and a permanent magnet or an electromagnet,

the windings are for generating electromagnetic force torques at the first and second rotors,

the electromagnetic force torque is magnetically transmitted to the second rotor by rotation of the first rotor or to the first rotor by rotation of the second rotor,

the electromagnetic torque is superimposed on a torque magnetically transmitted through the other rotor in either one of the first rotor and the second rotor.

2. The rotating electric machine according to claim 1,

the number of magnetic poles of the fixing part is N_SThe number of poles of the first rotor is N_LThe number of poles of the second rotor is N_HIs set to N_S＝N_L+N_HAnd N_S＝N_L-N_HMagnetically coupling the first rotor and the second rotor.

3. The rotating electric machine according to claim 1 or claim 2,

one of the first rotor and the second rotor is accelerated and decelerated by the superposition of the torque magnetically transmitted by the other rotor.

Technical Field

The present invention relates to a rotating electric machine using a magnetic reduction mechanism.

Background

Patent document 1 and non-patent document 1 disclose a rotating electric machine mechanism using a magnetic transmission mechanism. The rotating electric machine mechanism is configured by coaxially arranging a first rotor having a permanent magnet, a second rotor having a magnetic pole piece, and a fixed portion having a winding with a gap therebetween from the radially inner side. The first rotor is driven by applying a three-phase current to the fixed-section winding, and a reaction torque of the magnetic reduction gear is generated in the second rotor by the rotation of the first rotor. Thus, the magnetic reducer and the rotating electric machine are integrated, and the system can be made small or high in output without mechanical contact, with low vibration, low noise, and high transmission efficiency. In addition, the magnetic slip is generated when the allowable torque is exceeded, and thus the magnetic slip also functions as a torque limiter.

Disclosure of Invention

Problems to be solved by the invention

With regard to patent document 1 and non-patent document 1, the torque that can be generated in the rotating magnetic field of the winding of the fixed portion is transmitted to only one rotor at a reduced speed to the other rotor.

The purpose of the present invention is to achieve a rotary electric machine that is reduced in size for resource saving and cost reduction, and that has a high output for improving the output in a limited space.

For solving the problemsScheme(s)

In order to solve the above-described conventional problem, a rotating electrical machine according to one aspect of the present disclosure is a rotating electrical machine in which a first rotor, a fixed portion having a plurality of magnetic pole pieces and a winding in a circumferential direction, and a second rotor are coaxially arranged with a gap therebetween from a radially inner side, the first rotor and the second rotor are configured by a permanent magnet or an electromagnet, the winding is configured to generate electromagnetic force torque at the first rotor and the second rotor, the electromagnetic force torque is transmitted to the second rotor by rotating magnetism of the first rotor or transmitted to the first rotor by rotating magnetism of the second rotor, and the electromagnetic force torque overlaps torque transmitted by magnetism of the other rotor at one of the first rotor and the second rotor.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, the output density of the rotating electric machine can be increased.

The rotating electrical machine according to the present invention has an effect of generating torques in the two rotors by the rotating magnetic field of the winding of the stationary portion and transmitting the torque generated in one rotor to the other rotor at a reduced speed, and is useful for downsizing the rotating electrical machine for resource saving and cost reduction and for increasing the output of the rotating electrical machine in a limited space.

Drawings

Fig. 1 shows a conventional magnetic deceleration mechanism, and (a) is a plan view and (B) is a perspective view.

Fig. 2 is a diagram illustrating a magnetic effect on a conventional high-speed rotor and a stator, (a) is a plan view of a magnetic pole pair formed by permanent magnets of the high-speed rotor, (B) is a diagram illustrating a magnetic potential distribution formed by the permanent magnets of the high-speed rotor, (C) is a plan view of the stator, and (D) is a diagram illustrating a permeability (permeability) distribution formed by magnetic pole pieces.

Fig. 3 is a structural diagram showing a rotating electric machine according to an embodiment of the present invention, in which (a) is a perspective view and (B) is a sectional view showing a plane of a magnetic circuit.

Fig. 4 is a diagram showing the analysis result of the induced voltage generated in the stationary portion winding when each rotor of the present invention is rotated.

Fig. 5 is a diagram showing an analysis result of the transmission torque generated by the two rotor angle (phase) difference in the present invention.

Fig. 6 is a diagram showing an analysis result of torque when a three-phase sine wave current is applied to the coil of the present invention.

Fig. 7 is a diagram showing the torque generated by the two rotors when the operation is verified in the embodiment of the present invention.

Fig. 8 is a view showing the rotation angles of two rotors when the operation verification is performed in the embodiment of the present invention.

Detailed Description

Fig. 1 and 2 are diagrams for explaining the structure and deceleration principle of a conventional magnetic deceleration mechanism. First, the deceleration principle is explained with reference to these drawings.

In fig. 1, the conventional magnetic deceleration mechanism is configured such that a central high-speed rotor 100, an intermediate fixed part 200, and an outermost low-speed rotor 300 are coaxially arranged with a required gap therebetween. Each portion has a predetermined length in the axial direction. The high-speed rotor 100 is coupled to an output shaft of a motor or the like, for example, and receives a rotational force, which is not shown, and the high-speed rotor 100 is configured by an iron core made of a magnetic material, for example, having a shaft shape (or may be cylindrical), and a pair of magnetic poles 102, the pair of magnetic poles 102 being obtained by alternately arranging N poles and S poles uniformly in the circumferential direction on the outer periphery of the iron core, and the pair of magnetic poles 102 being configured by a permanent magnet. In the example of fig. 1, the number of pole pairs is two. The fixing portion 200 includes a plurality of pole pieces 201 arranged at predetermined intervals on the circumference so as to face the outer periphery of the pole pair 102, and the pole pieces 201 are made of a magnetic material and have a rod shape extending in the axial direction. The pole piece 201 is substantially rectangular in longitudinal section with the flat portions facing in the radial direction. The low-speed rotor 300 includes an annular body 301 and magnetic poles 302, wherein the annular body 301 is made of a magnetic material, and the magnetic poles 302 are formed by permanent magnets in which a plurality of N poles and S poles are alternately arranged in a circumferential direction on an inner periphery of the annular body 301.

Next, in FIG. 2As shown in fig. 2B, when the magnetic potential distribution F (θ) of the permanent magnet (see fig. 2 a) with respect to the rotation direction θ of the high-speed rotor 100 is assumed to be a sine wave, it can be set to F (θ) ═ AsinN_hTheta (wherein, N_hThe pole pair number of the high speed rotor 100. A is a coefficient). When the magnetic flux distribution R (θ) (which indicates the ease of passage of magnetic flux) at the outer periphery of the pole piece 201 of the fixing unit 200 in the radial direction shown in fig. 2C is also assumed to be a sinusoidal wave as shown in fig. 2D, it can be set such that R (θ) ═ R₀+R_asinN_STheta (wherein, N_SThe number of pole pieces as fixing portions. R₀、R_aRespectively coefficients).

Thus, the magnetic flux generated at the outer periphery of the pole piece of the fixed part

Represented by the following formula (1).

[ number 1 ]

In the formula (1), N in the first term_hNumber of pole pairs N with high speed rotor 100_hAre the same component. N in the second term_S-N_hAnd N_S+N_hAre higher harmonic components. That is, the magnetic flux generated at the outer periphery of the pole piece of the fixed part

Except for N_hIn addition to the basic component (main component) of (1), N may be also known_S-N_hAnd N_S+N_hThe higher harmonic components of these two types.

Next, when considering a case where the high-speed rotor 100 is rotated only by Δ θ while the fixed portion is held fixed, the magnetic potential distribution at this time becomes F (θ + Δ θ), while the magnetic conductance distribution becomes R (θ) because the fixed portion does not rotate. Then, the magnetic flux on the outer periphery of the magnetic pole piece of the fixed part at the time point when the high-speed rotor rotates by Δ θ

Represented by the following formula (2).

Number 2

In the formula (2), magnetic flux

N in the first item of (1)_hSince there is a + Δ θ component (θ + Δ θ), it is known that the component rotates at the same speed as the high-speed rotor 100. On the other hand, N in the second term_S-N_hAnd N_S+N_hAre higher harmonics of a speed different from that of the high-speed rotor 100, i.e., with respect to N_S-N_hWhich rotates only-N with respect to the rotation of Δ θ of the high-speed rotor 100_hΔθ/(N_S-N_h) In addition, with respect to N_S+N_hRotation of only N relative to rotation of Δ θ of the high speed rotor_hΔθ/(N_S+N_h) Therefore, it is known that the rotational speeds are different from the basic components. When the number of the low-speed rotors 300 is set to N_S-N_hOr N_S+N_hIn the case of one of the above, the low-speed rotor 300 rotates at the different rotational speed with respect to the set side.

Therefore, when the number of magnetic poles of the low-speed rotor 300 is N_IIs set to N_I＝N_S-N_hOr N_I＝N_S+N_hI.e. N when it is rewritten_S＝N_I+N_hOr N_S＝N_I-N_h(i.e., N)_S＝N_I±N_h). This is a condition for establishing the magnetic deceleration mechanism.

In addition, the reduction ratio G_rIs G_r＝±N_I/N_h. Further, the reduction ratio G_rFor the positive case, the high speed rotor 100 and the low speed rotor 300 are shown to rotate in the same direction at a reduction ratio G_rThe high speed rotor 100 and the low speed rotor 300 are shown to rotate in opposite directions for the negative case. However, a drive source for mechanically rotating the stator, typically a motor, needs to be added, and there is a new problem that the mechanism becomes complicated, large-sized, and expensive

(embodiment mode)

Therefore, in the present invention, in the conventional magnetic reduction mechanism shown in fig. 1, the windings are provided on the magnetic pole pieces of the fixed portion, and the two rotors can generate torque.

In one embodiment of the present invention (fig. 3), the magnetic speed reducer is constituted by a low-speed rotor 3 having a magnetic material 31 and a permanent magnet 30 provided from the outside, a fixed portion 2 having a coil 21 wound around a pole piece 20, and a high-speed rotor 1 having a permanent magnet 11 and a magnetic material 10. Here, the high-speed rotor 1 and the low-speed rotor 3 are examples of the first rotor and the second rotor, respectively, and the operation principle is established even if these are replaced, but in the embodiment, the low-speed rotor 3, which is a multi-pole, is disposed outside. The coil 21 wound around the pole piece 20 is formed by short-pitch concentrated winding, but the winding method is not limited thereto.

As described above, the rotating electrical machine according to the embodiment is configured such that the first rotor, the fixed portion 2 having the plurality of pole pieces 20 and the winding (coil 21) in the circumferential direction, and the second rotor are coaxially arranged with a gap therebetween from the radially inner side. The first and second rotors are constituted by magnetic materials 10 and 31, permanent magnets 11 and 30, or electromagnets. The windings are used to generate electromagnetic force torque in the first rotor and the second rotor, the electromagnetic force torque being magnetically transmitted to the second rotor by rotation of the first rotor or magnetically transmitted to the first rotor by rotation of the second rotor, and the electromagnetic force torque overlapping torque magnetically transmitted by one of the first rotor and the second rotor.

Next, the operation principle of the present invention will be explained. It is assumed that the number of pole pairs of the high-speed rotor 1, the number of pole pairs of the low-speed rotor 3, and the number of magnetic pole pieces of the fixing portion 2 satisfy the conditions of the magnetic deceleration mechanism described above. That is, the number of magnetic poles in the fixing section 2 is N_SThe number of poles of the first rotor is N_LThe number of poles of the second rotor is N_HIs set to N_S＝N_L+N_HAnd N_S＝N_L-N_HThe first rotor and the second rotor are magnetically coupled. At high speed rotor 1 at rotation speed ω_HThe frequency F of the back electromotive voltage generated at the coil 21 of the stationary part 2 during rotation_HIs N_Hω_H. On the other hand, the rotation speed ω of the low-speed rotor 3_LIs omega_H/G_rThe frequency F of the back electromotive voltage generated at the coil 21 of the stationary part 2 by the rotation of the low-speed rotor 3_LIs N_Lω_L＝(G_rN_H)(ω_H/G_r)＝F_H. As described above, in the rotating electric machine according to the present invention satisfying the conditions for establishing the magnetic deceleration mechanism, the frequencies of the back electromotive voltages generated in the coil 21 of the stationary unit 2 by the rotation of the high-speed rotor 1 and the low-speed rotor 3 are the same. Therefore, when the number of pole pieces of the high-speed rotor 1 and the fixed part 2 and the number of pole pieces of the low-speed rotor 3 and the fixed part 2 are combined so as to be rotatable as a three-phase permanent magnet brushless motor, for example, satisfying the conditions for establishing the magnetic deceleration mechanism, a torque is generated in both the rotors by a current applied to the coil 21 of the fixed part 2.

The output of the low-speed rotor 3 is set to ω_LThe rotation is fixed. When a frequency omega is applied to the coil 21 of the fixed part 2_HCurrent I, with respect to the torque T generated at the high speed rotor 1_HUsing a torque constant k_tHTo be T_H＝k_tHI, torque T additionally generated at the low-speed rotor 3_LUsing a torque constant k_tLTo be T_L＝k_tLI。

The torque generated at the high-speed rotor 1 due to the coil 21 current is equal to the reaction torque from the low-speed rotor 3 generated by the action as a magnetic speed reducer, which torque is transmitted to the low-speed rotor multiplied by the reduction ratio. Thus, when the torque T is output from the low-speed rotor 3_OWhen there is no apparent loss, T is_O＝T_L+G_rT_HCan beIt is known that the electromagnetic force torque generated at the low-speed rotor 3 by the stationary portion winding is overlapped with the torque magnetically transmitted by the high-speed rotor 1. That is, by superimposing the torque magnetically transmitted by one of the first rotor and the second rotor, the other of the first rotor and the second rotor can be accelerated or decelerated.

Next, a magnetic deceleration structure model was produced based on the principle of correlation, and an effect test was simulated. The rotating electric machine model is produced from the following elements.

Pole pair number of high speed rotor: 4

Pole pair number of low speed rotor: 8

Number of magnetic pole pieces of fixing part: 12

Reduction ratio: -2(═ 8/4)

Outermost diameter: 110mm

Axial length: 80mm

Number of turns of coil: 10

Magnetization of permanent magnet: 1.28T

First, since whether or not the high-speed rotor and the low-speed rotor generate torque is checked by applying current to the stationary-part coil, a counter electromotive voltage when the high-speed rotor and the low-speed rotor are rotated at the reduction ratio is checked.

The back electromotive voltage generated at the coil of the stator is determined under the conditions (a), (b), and (c) shown below.

(a) Fixing the low-speed rotor to make the high-speed rotor rotate forcibly at-60 r/min

(b) Fixing the high-speed rotor to make the low-speed rotor forcibly rotate at 30r/min

(c) The high speed rotor is forced to rotate at-60 r/min and the low speed rotor is forced to rotate at 30r/min

Fig. 4 shows the result. The counter electromotive voltage generated under the conditions (a) and (b) has the same voltage phase, and the counter electromotive voltage under the condition (c) in which the two rotors rotate at the reduction gear ratio is equal to the sum of the counter electromotive voltages under the conditions (a) and (b). Therefore, by applying a three-phase sinusoidal current to the stationary-part coil, it is found that torque can be generated in each of the high-speed rotor and the low-speed rotor.

Next, as the magnetic transmission mechanism, in order to confirm whether or not the torque of the high-speed rotor is transmitted to the low-speed rotor, the high-speed rotor is fixed and the low-speed rotor is forcibly rotated from the magnetically stable position, and the transmission torque generated by the difference in the angles (phases) of the two rotors deviated from the magnetically stable position is obtained. Fig. 5 shows the result. The maximum transmission torque of the two rotors is generated at a phase difference of about 11.25deg., and the maximum transmission torque of the high-speed rotor and the low-speed rotor is 38.6Nm and 85.8Nm, respectively. Therefore, it is found that the torque of the low-speed rotor and the torque of the high-speed rotor generate torques almost according to the reduction ratio, and the difference from the theoretical value is generated by the cogging torque.

In order to confirm the effect of the torque superposition, the torque of the low-speed rotor when the phases of the high-speed rotor and the low-speed rotor are changed was further determined by forcibly rotating the high-speed rotor at-60 r/min and the low-speed rotor at 30r/min and applying a sine wave current. Fig. 6 shows the result. Regardless of the phase difference, the torque of the low-speed rotor increases as the current increases. The torque of the low-speed rotor when the magnetic potential of amplitude 150A was applied to the coil was 89Nm with the phase difference set to 4deg., and the torque was increased by 44Nm compared to the case where no current was applied.

In the rotating electrical machine according to the present invention, the torque of the low-speed rotor when no current is applied is equal to the transmission torque generated by the phase difference between the low-speed rotor and the high-speed rotor, which is also true in a rotating electrical machine having a conventional magnetic deceleration mechanism. In a state where the phase difference is fixed, the torque of the low-speed rotor increases as the current increases, and therefore it is known that the reaction torque received from the high-speed rotor as the magnetic reduction gear overlaps with the torque generated at the low-speed rotor by the magnetic potential of the coil.

Finally, the operation was verified by setting the initial phase difference to 4deg., and the operation when the magnetic potential of amplitude 150A was applied to the coil was verified. Here, the high-speed rotor is rotated at 60r/min, and current is input in accordance with the rotational position of the high-speed rotor. At this time, a load L of 89.5Nm is applied to the low-speed rotor, and the torque generated in each rotor and the rotation speed of the low-speed rotor are determined. Fig. 7 and 8 show the results.

The average torque of the high-speed rotor and the low-speed rotor was-2.1 Nm and 88.8Nm, respectively, according to FIG. 7, and the average rotational speed of the low-speed rotor was 29.8r/min, according to FIG. 8. The average torque of the high-speed rotor should theoretically be zero, but is not zero due to torque fluctuations and the interval in which the averaging process is performed. In addition, the rotation speed ratio of the two rotors is almost in accordance with the reduction ratio. Finally, it is found that the torque of the low-speed rotor vibrates around 89Nm and hardly changes from time zero. This means that the phase difference of the two rotors remains on average 4deg., and according to fig. 5, a torque is generated in the low-speed rotor by the magnetic potential of 150A. That is, the torque as the reaction force of the magnetic reduction gear is superimposed on the torque generated by the coil current and is output from the low-speed rotor.

Although the rotating electric machine according to the present disclosure has been described above based on the embodiments, the present disclosure is not limited to the embodiments.

The present disclosure also includes embodiments that can be obtained by applying various modifications to the embodiments that will occur to those skilled in the art, and embodiments that can be realized by arbitrarily combining structural elements and functions in the embodiments within a scope that does not depart from the gist of the present disclosure.

Industrial applicability

The present disclosure can be applied to all rotating electrical machines using a magnetic reduction mechanism.

Description of the reference numerals

1. 100, and (2) a step of: a high-speed rotor; 2: a fixed part; 3. 300, and (2) 300: a low-speed rotor; 10. 31: a magnetic material; 11. 30: a permanent magnet; 20. 201: a magnetic pole piece; 21: a coil; 102: a pair of magnetic poles; 200: a fixed part.