JP2011114939A - Salient-pole rotor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress deformation or damage of a salient-pole rotor. <P>SOLUTION: The salient-pole rotor 1 includes a spindle 10 and a plurality of magnetic poles 20. The spindle 10 coaxially extends with a rotary shaft and is rotatably pivoted. The magnetic pole 20 includes a pole body 30, a coil 40 and a pole head 50. A plurality of pole bodies 30 are fixed to an outer periphery of the spindle, extend along the rotary shaft and are arranged by leaving intervals in a circumferential direction of the rotary shaft. The coil 40 is wound around a winding axis perpendicular to the rotary shaft in each pole body 30. A plurality of pole heads 50a, 50b and 50c are formed of conductors, are fixed to outer faces 32b of the pole bodies 30 and are disposed along the rotary shaft by leaving gaps 54a and 54b. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a structure of a salient pole rotor.

  The salient-pole synchronous motor has a salient-pole rotor that is coaxially extended with the rotation shaft and is rotatably supported, and a stator that is arranged on the outer periphery of the salient-pole rotor with a space therebetween. (For example, refer to Patent Documents 1 and 2).

  Here, a conventional salient pole rotor will be described with reference to FIGS. 4 and 5. FIG. FIG. 4 is a longitudinal sectional view of a conventional salient pole rotor. FIG. 5 is a plan view of a pole head of a conventional salient pole rotor.

  The salient pole rotor 101 has a main shaft 110 and a plurality of magnetic poles 120. The main shaft 110 extends coaxially with the rotating shaft and is rotatably supported by a bearing when installed on the synchronous motor. The plurality of magnetic poles 120 are fixed to the outer peripheral surface of the main shaft 110, extend along the rotation axis, and are arranged at intervals in the circumferential direction of the rotation shaft.

  Each magnetic pole 120 has a pole body 130, a coil (field winding) 140, and a pole head 150. The pole body 130 is fixed to the outer peripheral surface of the main shaft 10 and extends along the rotation axis. The coil 140 is wound around the pole body 130. The pole head 150 is formed in a single plate shape whose length in the rotation axis direction is slightly larger than the length in the rotation axis direction of the pole body 130, and covers the outer surface 132 b of the pole body 130. It is fixed to the pole body 130.

  The pole head 150 is positioned with respect to the pole body 130 by a reamer pin 160 inserted in the center thereof and fastened to the pole body 130 by a plurality of bolts 162.

  The salient pole type synchronous motor is started by an electromagnetic force acting between an eddy current flowing in the pole head 150 and a stator winding (not shown).

JP-A-6-343250 JP-A-10-322947

  As described above, eddy current flows through the pole head 150 at the time of starting the synchronous motor. However, if the slip frequency is high at the beginning of the start, the eddy current is concentrated on the surface of the pole head 150 due to the skin effect. As a result, the pole head 150 becomes hot.

  Here, the problem caused by the high temperature of the pole head 150 will be described with reference to FIGS. 6 and 7 are schematic vertical sectional views of a part of a pole body and a pole head of a conventional salient pole rotor.

  First, when the pole head 150 reaches a high temperature, as shown in FIG. 6A, the pole head 150 undergoes thermal expansion (thermal elongation) (deforms from a dotted line in FIG. 6A to a solid line). Since the pole head 150 is formed in a plate shape extending in the rotation axis direction, the extension in the rotation axis direction is particularly remarkable.

  Since the pole head 150 is fixed to the pole body 130, a frictional force acts on the inner surface 152a of the pole head 150 and the outer surface 132b of the pole body 130 as the pole head 150 is thermally expanded. Therefore, as shown in FIG. 6B, the vicinity of the outer surface 132b of the pole body 130 is deformed with the thermal expansion of the pole head 150 (deformed from the dotted line in FIG. 6B to the solid line). Stress concentrates on the inner end of the pole body 130 (the portion surrounded by the one-dot chain line in FIG. 6B).

  When the amount of thermal expansion of the pole head 150 is further increased, the pole body 130 returns to the original shape as shown in FIG. 7A (deforms from the dotted line in FIG. 7A to the solid line). Thereafter, when the synchronous motor starts or stops synchronous operation, the eddy current disappears, the pole head 150 is cooled, and when the pole head 150 contracts, the friction acting on the inner surface 152 a of the pole head 150 and the outer surface 132 b of the pole body 130. Due to the force, the vicinity of the outer surface 132b of the pole body 130 is deformed (deformed from the dotted line in FIG. 7B to the solid line), and the inner end of the pole body 130 (the portion surrounded by the dotted line in FIG. 7B). Will concentrate stress.

  If such deformation and stress concentration occur repeatedly, parts such as the pole body 130, the pole head 150, the bolt 162, or the main shaft 110 may be deformed or damaged. Further, the deformation of these components causes the salient pole rotor 101 to rotate unbalanced.

  Accordingly, the present invention has been made to solve the above-described problems, and an object thereof is to suppress deformation or breakage of the salient pole rotor.

  In order to achieve the above object, a salient pole rotor according to the present invention includes a main shaft that extends coaxially with a rotating shaft and is rotatably supported, and is fixed to the outer periphery of the main shaft along the rotating shaft. A plurality of pole bodies extending and arranged at intervals in the circumferential direction of the rotation shaft, a coil wound around a winding axis perpendicular to the rotation axis with respect to each pole body, and each of the pole bodies And a plurality of pole heads made of a conductor fixed to the outer surface in the radial direction of the rotation axis and arranged with a gap therebetween along the rotation axis.

  According to the present invention, deformation or breakage of the salient pole rotor can be suppressed.

It is a longitudinal cross-sectional view of the salient pole type rotor which concerns on embodiment of this invention. FIG. 2 is a cross-sectional view taken along the line II-II in FIG. 1. It is a top view of the pole head of the salient pole type rotor concerning the embodiment of the present invention. It is a longitudinal cross-sectional view of the conventional salient pole rotor. It is a top view of the pole head of the conventional salient pole rotor. It is a typical longitudinal cross-sectional view of a part of a pole body and a pole head of a conventional salient pole rotor. It is a typical longitudinal cross-sectional view of a part of a pole body and a pole head of a conventional salient pole rotor.

  The structure of the salient pole rotor according to the embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a longitudinal sectional view of a salient pole rotor according to the present embodiment. 2 is a cross-sectional view taken along the line II-II in FIG. FIG. 3 is a plan view of the pole head of the salient pole rotor according to the present embodiment.

  The salient pole rotor 1 is a six pole block salient pole rotor used in a rotating electric machine such as a salient pole synchronous motor, and has a main shaft 10 and six magnetic poles 20. In this embodiment, a 6-pole salient-pole rotor is used as an example. However, the present invention is not limited to this. For example, a 4-pole, 8-pole, or 10-pole type is used. The salient pole rotor may be used.

  The main shaft 10 extends coaxially with the rotating shaft and is rotatably supported by a slide bearing or the like when installed on a rotating electrical machine. A magnetic pole mounting portion 12 is formed at an intermediate portion of the main shaft 10 in the rotation axis direction. As shown in FIG. 2, the magnetic pole mounting portion 12 has a substantially hexagonal column shape in cross section.

  Six dovetail insertion grooves 14 extending in the direction of the rotation axis are formed on the outer peripheral surface of the magnetic pole mounting portion 12, and the six dovetail insertion grooves 14 are arranged at equal intervals in the circumferential direction. The dovetail insertion groove 14 becomes wider from the outer peripheral surface of the magnetic pole mounting portion 12 toward the inside in the radial direction, and has a substantially trapezoidal cross section.

  The six magnetic poles 20 are fixed to the outer peripheral surface of the main shaft 10, extend along the rotation axis, and are arranged at intervals in the circumferential direction of the rotation shaft. Each magnetic pole 20 has a pole body 30, a coil (field winding) 40, and a pole head 50.

  The pole body 30 is fixed to the outer peripheral surface of the main shaft 10 and extends along the rotation axis. A dovetail portion 34 extending along the rotation axis is formed on a radially inner surface (hereinafter referred to as “inner surface of the pole body 30”) 32a of the rotation axis of the pole body 30. This dovetail portion 34 has a substantially trapezoidal shape whose cross section corresponds to the shape of the dovetail insertion groove 14.

  The pole body 30 is fixed to the main shaft 10 (the magnetic pole mounting portion 12) by inserting the dovetail portion 34 into the dovetail insertion groove 14 along the rotation axis, and further in the gap between the dovetail portion 34 and the dovetail insertion groove 14. This is done by inserting a shaped key 36.

  The coil 40 is wound around the pole body 30 and, more specifically, is wound around a winding axis perpendicular to the rotation axis.

  Each magnetic pole 20 has, for example, three pole heads 50a, 50b, 50c (collectively referred to as “pole head 50”), and the three pole heads 50 are spaced from each other along the rotation axis by a gap 54a. , 54b are arranged. The pole head 50 of each magnetic pole 20 is divided into three in the rotation axis direction. The three pole heads 50 are made of a conductor such as high-strength steel, for example, and are formed in a substantially plate shape.

  The three pole heads 50 are fixed to the outer surface 32b of the pole body 30 so as to cover a radially outer surface (hereinafter referred to as “the outer surface of the pole body 30”) 32b of the rotation axis of the pole body 30. . An inner surface (hereinafter referred to as “inner surface of the pole head 50”) 52a in the radial direction of the rotation shaft of each pole head 50 is formed so as to be in close contact with the outer surface 32b of the rotation shaft of the pole body 30. The widths Da, Db, Dc in the rotation axis direction of the pole heads 50a, 50b, 50c are designed to be substantially the same. The widths da and db of the gaps 54a and 54b in the rotation axis direction are designed to be substantially the same.

  A pin hole for inserting the reamer pin 60 is formed at the center of each pole head 50. On the other hand, pin holes are formed at positions corresponding to the pin holes on the outer surface 32 b of the pole body 30. Each pole head 50 is formed with a plurality of bolt holes for inserting a plurality of bolts 62. On the other hand, a plurality of bolt holes are formed at positions corresponding to the plurality of bolt holes on the outer surface 32 b of the pole body 30.

  Each pole head 50 is positioned on the outer surface 32 b of the pole body 30 by a reamer pin 60 and then fixed to the pole body 30 by a plurality of bolts 62.

  The effect of the salient pole rotor 1 according to the embodiment of the present invention will be described.

  One pole head 150 of the conventional salient pole rotor 101 is provided for each magnetic pole 120 and has an integral structure (see FIG. 4). On the other hand, three pole heads 50 of the salient pole rotor 1 according to the present embodiment are provided in each magnetic pole 120, and the three pole heads 50a, 50b, 50c are along the rotation axis. Thus, a divided structure is formed with the gaps 54a and 54b arranged (see FIG. 1).

  As described above, the pole head 50 becomes a high temperature due to the eddy current flowing on the surface thereof, and is thermally expanded (heat stretched). The amount of thermal expansion is proportional to the temperature change amount, the coefficient of thermal expansion of the material of the pole head 50, and the size.

  Here, in the salient pole rotor 1 according to the present embodiment, since the pole head 50 has a divided structure, each of the pole heads 50a, 50b, 50c is heated around the reamer pin 60 located at the center. When expanded, the thermal elongation is relaxed by the gaps 54a and 54b. Therefore, compared to the conventional salient pole type rotor 101, the amount of thermal expansion in the direction of the rotation axis of the entire pole head 50 is reduced, and the stress applied to the pole body 30 and the like is also reduced. As a result, deformation or breakage of the salient pole rotor 1 can be suppressed, and the rotation of the salient pole rotor 101 can also be suppressed from becoming unbalanced.

  In this embodiment, three pole heads 50 are provided for each magnetic pole 120. However, if two or more pole heads 50 are provided for each magnetic pole 120, the above-described effects can be obtained. When the pole head 50 is made of high-tensile steel, the sum of the widths d of one or more gaps 54 in the rotation axis direction is 1% of the sum of the widths D of the plurality of pole heads 50 in the rotation axis direction. The content is preferably 2% or less.

DESCRIPTION OF SYMBOLS 1 ... Rotor, 10 ... Main shaft, 12 ... Magnetic pole attaching part, 14 ... Dovetail insertion groove, 20 ... Magnetic pole, 30 ... Pole body, 32a ... Pole body inner surface, 32b ... Pole body outer surface, 34 ... Dovetail part, 36 ... Key, 40 ... Coil, 50 (50a, 50b, 50c) ... Pole head, 52a ... Pole head inner surface, 52b ... Pole head outer surface, 54 (54a, 54b) ... Gap, 60 ... Reamer pin, 62 ... Bolt

Claims (4)

A main shaft extending coaxially with the rotation shaft and rotatably supported;
A plurality of pole bodies fixed to the outer periphery of the main shaft, extending along the rotation axis, and arranged at intervals in the circumferential direction of the rotation shaft;
A coil wound around a winding axis perpendicular to the rotation axis for each of the pole bodies;
A plurality of pole heads made of a conductor, fixed to the outer surface in the radial direction of the rotation axis of each of the pole bodies, and arranged with a gap along the rotation axis.
A salient pole rotor characterized by comprising:   The sum of the widths in the rotation axis direction of the gaps formed between the plurality of pole heads is 1% or more and 2% or less of the sum of the widths in the rotation axis direction of the plurality of pole heads. Item 10. The salient pole rotor according to Item 1.   The salient pole rotor according to claim 1 or 2, wherein each of the pole heads is fixed to the pole body by a bolt.   4. The salient pole rotor according to claim 1, wherein each of the pole heads is positioned with respect to the pole body by a reamer pin. 5.

Images