JP2013081336A - Rotating electrical machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotating electrical machine that smoothly rotates a rotor by suppressing effects of pulsation torque on the rotation of the rotor.SOLUTION: In the rotating electrical machine having the rotor with permanent magnets, U-shaped front stator cores arranged to connect via spaces front end portions of two adjacent permanent magnets of the permanent magnets, U-shaped back stator cores arranged to connect via spaces back end portions of two adjacent permanent magnets of the permanent magnets only one of which is common to the former two permanent magnets, front coils wound on the U-shaped front stator cores, and back coils wound on the U-shaped back stator cores, when an area of opposition of sides of stator cores leading with respect to a rotation direction to the permanent magnets is smaller than an area of opposition of sides of stator cores trailing with respect to the rotation direction to the permanent magnets, a pulse current is supplied to the coils wound on the stator cores trailing with respect to the rotation direction to drive the rotor in the rotation direction.

Description

  The present invention relates to a rotating electrical machine, and more particularly to a rotating electrical machine with reduced pulsating torque.

  In a conventional rotating electrical machine, for example, a generator, energy such as hydraulic power or thermal power is converted into rotational energy, and the generator is driven by the converted rotational energy to generate electric power. Generally used generators include a rotor in which a permanent magnet having N poles and S poles is attached to a rotating shaft, an armature core having magnetic poles corresponding to the number of magnetic poles formed by the permanent magnets, and the armature core The generator coil is wound around and the rotor is driven to rotate, thereby generating an AC magnetic field in the armature core and generating an AC voltage in the generator coil by the generated AC magnetic field.

  By the way, an armature core constituting a rotating electric machine such as a generator or an electric motor may be disposed close to a magnet attached to the rotor to supply a sufficient magnetic field to a coil wound around the armature core. desired. When the permanent magnet and the armature core are arranged close to each other, an attractive force acts between the permanent magnet and the iron core. This attractive force is particularly large when a strong permanent magnet is used to improve the output of the rotating electrical machine.

  Further, this suction force varies depending on the rotation angle of the rotor, and affects the rotation torque of the rotor. When this torque, that is, torque based on the magnetic attractive force between the armature and the rotor (pulsation torque) increases, the rotational angular speed of the rotor varies, and the generator has abnormal vibration or noise. Problems occur. For example, in a generator used for wind power generation or the like, the starting torque at which the rotor blades start to move increases. Moreover, the resistance for continuously rotating the rotor blades also increases. Therefore, it is difficult to generate power in a breeze.

  Patent Document 1 is known as a technique for suppressing such a problem caused by pulsating torque. According to Patent Document 1, a magnet in which an even number of magnetic poles are arranged in the rotation direction of a rotating shaft, and a yoke in which an iron piece corresponding to the even number of magnetic poles of the magnet is disposed close to the magnetic pole and coaxial with the rotating shaft, 3 or more of the power generation means including the power generation means are coupled by the rotating shaft, and the magnets and yokes of one power generation means and the magnets and yokes of the other power generation means are relatively rotated, respectively. The force attracted by the iron pieces and the force attracted by the magnet pieces of the other power generation means and the iron pieces of the yoke are offset.

JP 2009-240159 A

  According to the prior art, in order to suppress the pulsating torque, the power generation means has a structure in which a plurality of electromotive means are connected to one rotating shaft.

  Here, the electromotive means includes a permanent magnet in which magnetic poles are arranged radially and alternately along the circumferential direction with respect to a rotating shaft to which a rotational force is supplied from the outside, and a bobbin is provided on the outer periphery of the rotating shaft. A coil wound around, a yoke for inducing magnetic flux generated from the permanent magnet to interlink with the coil, and a radial and circumferential direction with respect to the rotating shaft, and magnetized by the permanent magnet. And an attraction means having a plurality of attracted pieces. The attraction means is means for reducing pulsation torque, which is attraction applied to the rotating shaft, by canceling out to some extent the attraction acting between the pole of the permanent magnet and the attracted piece.

  For this reason, according to the said prior art, the structure of an electric power generation means becomes complicated. In addition, it is difficult to reduce the size of the power generation means.

  The present invention has been made in view of these problems, and provides a rotating electrical machine capable of suppressing the influence of pulsating torque on the rotation of the rotor and rotating the rotor smoothly.

  In order to solve the above problems, the present invention employs the following means.

A rotor provided with a plurality of permanent magnets arranged so as to be concentric with the rotation axis and in parallel with the rotation axis at an equal interval and the magnetization direction;
A U-shaped first front stator core disposed so as to connect the front end portions of two adjacent permanent magnets of the permanent magnets via a gap;
A U-shaped first that is arranged so as to connect the back end portions of two permanent magnets adjacent to each other among the permanent magnets and only one of the two permanent magnets through a gap. The rear stator core,
A rotary electric machine comprising: a first front coil wound around the U-shaped first front stator core; and a first back coil wound around the U-shaped first rear stator core. A concave space formed between opposing sides of the first U-shaped first front stator core, a space formed between opposing sides of the adjacent U-shaped first front stator core, and a combination of these spaces A second front stator core disposed in a space to be formed, a concave space formed between opposing sides of the U-shaped first rear stator core, and an opposing U-shaped first rear stator core. A space formed between the two sides, a second back stator core disposed in a space connecting these spaces, a second front coil wound around the second front stator core, and a winding around the second back stator core The second back coil, The stator core side that precedes the rotation direction among the sides of the stator core that faces the permanent magnet, and the permanent magnet has a facing area between the side of the stator core that follows in the rotation direction and the permanent magnet. When the area is smaller than the facing area, a pulse current is supplied in a direction in which the permanent magnet is repelled to a coil wound around the stator core that follows the rotation direction.

  Since this invention is provided with the above structure, it can suppress the influence which it has on the rotation of the rotor of a pulsation torque, and can provide the rotary electric machine which can rotate a rotor smoothly.

It is a perspective view explaining the rotary electric machine used as the premise of this invention. It is a schematic diagram which expand | deploys and shows the rotor and stator of a rotary electric machine. It is a figure explaining a rotor. It is a figure explaining the torque which acts on a rotor. It is a figure explaining the torque which acts on a rotor. It is a figure explaining the torque which acts on a rotor. It is a figure explaining the torque which acts on a rotor. It is a figure explaining the modification of a rotary electric machine. It is a figure explaining a stator iron core. It is a figure explaining the modification of a stator iron core. It is a figure explaining the suppression operation of pulsation torque by pulse current. It is a figure explaining the suppression operation of pulsation torque by pulse current.

  Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view illustrating a generator according to the embodiment, FIG. 2 is a development view in which the rotor and armature portions of the generator shown in FIG. 1 are developed in the circumferential direction, and FIG. It is a figure explaining the rotor shown in FIG.

  In these drawings, 12 is a rotor, 15 is a rotating shaft of the rotor 12, 12M (12M-1, 12M-2...) Is a permanent magnet, concentric with the rotating shaft 15 and the rotating shaft 15. A plurality of them are arranged in parallel at equal intervals and with alternating magnetization directions. Reference numeral 13 denotes a front stator iron core, and reference numeral 14 denotes a rear stator iron core. The front stator core and the back stator core are accommodated in a housing (not shown).

  A rotary shaft 15 passes through the rotor 12, and the rotary shaft 15 is supported by the housing via a bearing (not shown).

  The magnetic plates 12F and 12R are arranged before and after the rotation direction W of the permanent magnet 12M. In addition, a non-magnetic plate 12C is disposed between adjacent permanent magnets 12M via magnetic plates 12F and 12R. A stainless steel plate, a bakelite plate or the like is used as the nonmagnetic plate 12C, and an electromagnetic steel plate is used as the magnetic plates 12F and 12R.

  The front stator core 13 (13-1, 13-2...) Has a gap between the front end portions of two adjacent permanent magnets 12M-1, 12M-2 among the plurality of permanent magnets 12M. Connecting. The front stator core 13 can be formed in a U-shape. Moreover, the coil 11 is each wound around a U-shaped front stator iron core, and these coils are connected in series, for example.

  14 (14-1, 14-2...) Is a back stator core, and a gap is formed between the back end portions of two adjacent permanent magnets 12M-2, 12M-3 among the plurality of permanent magnets. Connect. The back stator core can be formed in a U-shape. Further, coils 16 are wound around the U-shaped rear stator iron cores, and these coils are connected in series, for example.

The rear stator iron core is arranged so that one of the permanent magnets connected by the front stator iron core 13 and the rear end of another permanent magnet adjacent thereto are connected via a gap as described above. can do. As a result, the magnetic flux passing through the permanent magnet → the front stator core → the permanent magnet → the back stator core → the permanent magnet →... Is common, and an output can be efficiently obtained from the power generation coil. ,
4, 5, 6, and 7 are diagrams for explaining the torque acting on the rotor. FIG. 4 shows that one end of the permanent magnet 12 </ b> M of the rotor is opposed to the entire front stator core, and the other end of the permanent magnet is It is in a position facing the rear stator iron core over the entire surface.

  FIG. 5 shows a state in which the rotor 12 is rotated and the permanent magnet has moved to the left by a half of the magnet width. The latter half of the permanent magnet in the moving direction (the right half of the permanent magnet) and the magnetic plate 12R Opposite the front stator core and the back stator core.

  FIG. 6 further shows a state in which the rotor has rotated and the permanent magnet has moved ½ of the magnet width in the left direction, and the permanent magnet does not face either the front stator core or the back stator core.

  FIG. 7 further shows a state in which the rotor has rotated and the permanent magnet has moved 1/2 of the magnet width to the left, and the front half of the permanent magnet in the rotational direction and the magnetic plate 12F are the front stator core and the rear stator. Opposite the iron core.

  By the way, “reluctance torque” and “magnet torque” act on the rotating electrical machine. The reluctance torque is a torque based on the force with which the magnet attracts a magnetic body such as an iron core, and the magnet torque is a torque based on the force with which the magnetic poles repel or attract each other.

  When the permanent magnet is in the position of FIG. 4, the magnetic flux φm by the permanent magnet passes through the permanent magnet → the rear stator core → the permanent magnet → the front stator core → and is linked to the power generating coils 11 and 16. Along with the linkage, an electromotive force e is induced in the power generating coils 11 and 16 wound around the front stator core and the back stator core. When a load current i flows through the power generation coil, a load magnetic flux 2φc is generated. The load magnetic flux 2φc mainly passes through the magnetic plates 12F and 12R arranged before and after the rotation direction of the permanent magnet (relative permeability μs = 1 of the permanent magnet = 1, μs = 6000 of the magnetic material. Therefore, the magnetic flux. Most of it passes through the magnetic plate).

  When the permanent magnet is at the position shown in FIG. 5, a part αφm of the magnetic flux φm by the permanent magnet passes through the permanent magnet → the rear stator core → the permanent magnet → the front stator core →. At this time, the reluctance torque which tries to rotate the rotor in the right direction is acting on the permanent magnet. This reluctance torque causes pulsation torque. The magnetic flux αφm is linked to the power generation coil. A part βφm of the magnetic flux φm passes through the magnetic plates 12F and 12R and returns to the permanent magnet.

  Along with the linkage, an electromotive force e is induced in the power generation coil wound around the stator iron core, a load current ic flows through the power generation coil, and a load magnetic flux 2φc is generated.

  The load magnetic flux 2φc mainly passes through the magnetic plates 12F and 12R arranged before and after the rotation direction of the permanent magnet. That is, a part φc1 of 2φc passes through the magnetic plate 12R, and a part φc2 of 2φc passes through the magnetic plate 12F.

  In this way, the magnetic flux φc1 + βφm and the magnetic flux φC2-βφm pass through the rotor magnetic plates 12F and 12R, respectively. This magnetic flux generates torque that drives the rotor in the left direction.

  The torque for driving the rotor in the left direction is opposite to the reluctance torque acting between the permanent magnet and the stator core. For this reason, the pulsation torque based on the reluctance torque acting between the permanent magnet and the stator iron core can be suppressed.

  When the permanent magnet is in the position shown in FIG. 6, the magnetic flux flowing from the permanent magnet into the stator core cancels out in the coil. For this reason, no voltage is induced in the power generation coil.

  When the permanent magnet is at the position shown in FIG. 7, a part αφm of the magnetic flux φm generated by the permanent magnet passes through the permanent magnet → the rear stator core → the permanent magnet → the front stator core →. At this time, a reluctance torque that tries to rotate the rotor in the left direction acts on the permanent magnet. This reluctance torque causes pulsation torque. The magnetic flux αφm is linked to the power generation coil. Further, a part βφm of the magnetic flux φm passes through the magnetic plates 12F and 12R and returns to the permanent magnet.

  Along with the linkage, an electromotive force e is induced in the power generation coil wound around the back stator core, a load current ic flows through the power generation coil, and a load magnetic flux φc is generated.

  The load magnetic flux φc passes through the magnetic plates 12F and 12R arranged mainly in the front and rear directions in the rotation direction of the permanent magnet. That is, a part φc1 of φc passes through the magnetic plate 12F, and a part φc2 of φc passes through the magnetic plate 12R.

  That is, the magnetic flux φc1 + βφm and the magnetic flux φC2-βφm pass through the rotor magnetic plates 12F and 12R, respectively. The magnetic flux generates torque that drives the rotor in the right direction.

  The torque for driving the rotor in the right direction is opposite to the reluctance torque acting between the permanent magnet and the stator core. For this reason, the pulsation torque based on the reluctance torque acting between the permanent magnet and the stator iron core can be suppressed.

  FIGS. 8 and 9 are diagrams for explaining a modification of the rotating electrical machine. FIGS. 9A and 9B are diagrams illustrating a stator iron core (a U-shaped stator iron core (first stator iron core) 13-1 and a first stator iron core. FIG. 9C is a diagram for explaining a combination state of the stator iron core 13-1 ′). 8 that are the same as those shown in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted.

  In FIG. 8, 13-1 ′, 13-2′13-3 ′... Are second front stator cores. For example, one leg of the second front stator core 13-2 ′ is The U-shaped front stator iron core (first front stator iron core) 13-2 is disposed in a concave space formed between opposing sides, and the other leg is adjacent to the U-shaped front stator iron core 13-1. , 13-2, and is formed in a space formed between opposing sides, and these legs are connected by a bridge portion B.

  Similarly, one leg of the second back stator core 14-2 ′ is formed in a concave space formed between opposing sides of the U-shaped back stator core (first back stator core) 14-2. The other leg is disposed in a space formed between the opposing sides of the adjacent U-shaped rear stator cores (first rear stator cores) 14-1 and 14-2. Are connected by a bridge part B.

  In the first embodiment, U-shaped stator cores (first stator cores) are arranged at intervals in the rotational direction. For this reason, for example, when the rotor is at the position shown in FIG. 6, the magnetic flux emitted from the permanent magnet is not effectively used. According to the present embodiment, a second stator iron core, for example, a second rear stator iron core 14-2 'is added, and one leg thereof is an opposite side of the U-shaped rear stator iron core 14-2. These legs are disposed in a concave space formed between them, and the other leg is disposed in a space formed between opposing sides of the adjacent U-shaped rear stator cores 14-1 and 14-2. Are connected by a bridge part B. For this reason, the permanent magnet of the rotor is placed at a position that affects any of the stator cores, and the output of the rotating electrical machine can be increased.

  In the above example, the U-shaped stator core (first stator core) 13-1 in which the front stator core and the rear stator core are arranged at intervals in the rotation direction shown in FIG. 9A, one leg shown in FIG. 9A is disposed in a concave space formed between opposing sides of the U-shaped stator iron core (first stator iron core), and the other leg is adjacent to the Although it is arranged in a space formed between opposing sides of the letter-shaped stator core, and these legs are formed by the second stator core 13-1 ′ connected by the bridge portion B, as shown in FIG. The U-shaped stator cores a and b can be formed by being alternately inclined along the front side magnetic pole position on the outer periphery of the rotor and inclined to the front side and the back side of the rotary shaft. Similarly, the U-shaped stator cores a and b can be formed by being alternately inclined along the back side magnetic pole position on the outer periphery of the rotor and inclined to the front side and the back side of the rotating shaft.

  FIGS. 11A and 11B are diagrams for explaining the pulsation torque suppression operation by the pulse current, and are development views in which the rotor and armature portions of the generator shown in FIG. 8 are developed in the circumferential direction. In addition, (1)-(10) in FIGS. 11-1 and 11-2 has shown the movement position of the rotor for every time.

  As shown in FIGS. 11-1 (2) to (3) and FIGS. 11-2 (6) to (7), for example, among the sides of the stator core facing the permanent magnet 12M-1, the rotation direction (example in the figure) In this case, the facing area between the side a of the stator iron core 14-1 ′ preceding in the left direction and the permanent magnet 12M-1 is such that the side b of the stator iron core 14-1 following in the rotation direction faces the permanent magnet. When the area is smaller, that is, the reluctance torque acting between the side a of the stator core 14-1 ′ preceding in the rotation direction and the permanent magnet is the side b of the stator core 14-1 following in the rotation direction. When the reluctance torque acting between the permanent magnet and the permanent magnet is smaller (in this case, the rotor of the rotating electrical machine is located between the side b of the stator core 14-1 following in the rotation direction and the permanent magnet). Rotation by the reluctance torque that works So that a magnetic pole is generated in a direction in which the permanent magnet is repelled by a coil wound around the stator core 14-1 preceding the rotation direction (different from the power generation coil). Supply pulse current.

  Here, in FIGS. 11A and 11B, the magnetic poles at the positions indicated by “N” and “S” on the stator iron core are coils wound around the magnetic poles (for example, cogging suppression coils N1 to N4). The magnetic pole formed by the pulse current supplied to is shown. By generating magnetic poles in this manner, for example, the reluctance torque acting between the permanent magnet 12M-1 and the side b of the stator iron core 14-1 following in the rotational direction is suppressed, and pulsation based on the reluctance torque is suppressed. Torque can be suppressed. Note that the cogging suppression coil may be provided at one location (for example, only N1), and it is not essential to provide a plurality of cogging suppression coils. Further, the supply timing of the pulse current supplied to the cogging suppression coil can be obtained from a position sensor or the like that detects the rotational position of the rotor.

  In the above example, the pulse current is supplied so that the magnetic pole is generated in the direction of repelling the permanent magnet. However, the reluctance torque is suppressed by supplying the pulse current in the direction of attraction and driving the rotor. You can also

  As described above, according to the embodiment of the present invention, the pulsation torque based on the reluctance torque can be suppressed. Therefore, torque pulsation in the rotating electrical machine can be suppressed and smooth rotation can be obtained. As mentioned above, although embodiment of this invention was described taking the generator as an example, it is applicable similarly to an electric motor.

DESCRIPTION OF SYMBOLS 10 Rotating electrical machine 12 Rotor 13 Front stator iron core 14 Rear stator iron core 15 Rotating shaft 12M Permanent magnet 12F, 12R Magnetic board 12C Non-magnetic board N1-N4 Cogging suppression coil

Claims (4)

A rotor provided with a plurality of permanent magnets arranged so as to be concentric with the rotation axis and in parallel with the rotation axis at an equal interval and the magnetization direction;
A U-shaped first front stator core disposed so as to connect the front end portions of two adjacent permanent magnets of the permanent magnets via a gap;
A U-shaped first that is arranged so as to connect the back end portions of two permanent magnets adjacent to each other among the permanent magnets and only one of the two permanent magnets through a gap. The rear stator core,
A rotary electric machine comprising: a first front coil wound around the U-shaped first front stator core; and a first back coil wound around the U-shaped first rear stator core.
A concave space formed between opposing sides of the U-shaped first front stator core, a space formed between opposing sides of the adjacent U-shaped first front stator core, and these A second front stator core disposed in a space connecting the spaces;
A concave space formed between opposing sides of the U-shaped first back stator core, a space formed between opposing sides of the adjacent U-shaped first back stator core, and these A second rear stator core disposed in a space for joining the spaces;
A second front coil wound around a second front stator core;
A second back coil wound around a second back stator core;
With
Of the sides of the stator core facing the permanent magnet, the facing area between the side of the stator core preceding in the rotation direction and the permanent magnet is the facing area between the side of the stator core following in the rotation direction and the permanent magnet. A rotating electric machine that supplies a pulse current in a direction in which the permanent magnet is repelled to a coil wound around a stator core that follows the rotation direction. The rotating electrical machine according to claim 1, wherein
The first and second front stator cores are U-shaped stator cores, and the U-shaped stator core and the second front stator core are arranged along the front-side magnetic pole position on the outer periphery of the rotor. A rotating electrical machine characterized by being alternately inclined to the front side and the back side of a rotor. The rotating electrical machine according to claim 1, wherein
The first and second back stator cores are U-shaped stator cores, and the U-shaped stator core and the second back stator core are arranged along the back-side magnetic pole position on the outer periphery of the rotor. A rotating electrical machine characterized by being alternately inclined to the front side and the back side of a rotor. A rotor provided with a plurality of permanent magnets arranged so as to be concentric with the rotation axis and in parallel with the rotation axis at an equal interval and the magnetization direction;
A U-shaped first front stator core disposed so as to connect the front end portions of two adjacent permanent magnets of the permanent magnets via a gap;
A U-shaped first that is arranged so as to connect the back end portions of two permanent magnets adjacent to each other among the permanent magnets and only one of the two permanent magnets through a gap. The rear stator core,
A rotary electric machine comprising: a first front coil wound around the U-shaped first front stator core; and a first back coil wound around the U-shaped first rear stator core.
A concave space formed between opposing sides of the U-shaped first front stator core, a space formed between opposing sides of the adjacent U-shaped first front stator core, and these A second front stator core disposed in a space connecting the spaces;
A concave space formed between opposing sides of the U-shaped first back stator core, a space formed between opposing sides of the adjacent U-shaped first back stator core, and these A second rear stator core disposed in a space for joining the spaces;
A second front coil wound around a second front stator core;
A second back coil wound around a second back stator core;
With
Of the sides of the stator core facing the permanent magnet, the facing area between the side of the stator core preceding in the rotation direction and the permanent magnet is the facing area between the side of the stator core following in the rotation direction and the permanent magnet. When the number is less, a rotating electric machine is characterized in that a pulse current is supplied to a coil wound around a stator core in a direction in which the permanent magnet is attracted or repelled to drive the rotor in the rotational direction.