JPS5972949A - Salient-pole type lumped pole rotor - Google Patents

Abstract

PURPOSE:To alleviate the influence of heat loss at the starting time by burying a burying material having excellent electroconductivity and thermal conductivity in a section having remarkably large eddy current of the head of a pole. CONSTITUTION:Grooves 7 are formed on a lumped pole head 4, electroconductive and thermal conductive members 8 such as copper or the like are arranged in the grooves 7, and the head 4 is fixed by thermal engagement or a magnetic material 9 so as to prevent the gap for disturbing the heat insulating action and magnetic flux passing action. The positions of the members 8 to be buried are intermediate of heat loss generating layers. Thus, even if the magnetic flux is concentrated at the part from the surface of the head 4 to the prescribed impregnating depth at the starting time to generate heat, the heat is not conducted to the lower part by the thermal conduction of the member 9 buried in the lower part from the intermediate layer, thereby spreading the thermal capacity.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a salient-pole block magnetic pole rotor used in a synchronous motor or the like.

[Technical background of the invention and its problems]

BACKGROUND ART A block magnetic pole type synchronous motor equipped with a salient pole block magnetic pole rotor is widely used as a self-starting type synchronous motor that performs heavy load starting because the heat capacity of the magnetic pole head is large.

The specific structure of a conventional block magnetic pole type synchronous motor will be explained based on FIGS. 1, 2, and 3.

The stator is composed of a stator core 1 made of laminated thin iron plates and coils 2 housed in a number of grooves provided on the inner diameter side of the stator core 1. The block magnetic poles of the rotor include those in which the body 3 and the head 4 are made integrally from one base material (= winding 6 is wound through an insulator 5, and the body 3 and the head 4 are made integrally as shown in FIG. 2). There is one in which the head 4 is manufactured separately and assembled into one piece by tightening with bolts.

As described above (= the configured lump magnetic pole type synchronous motor uses the torque generated by the eddy current flowing in the magnetic pole head at startup to start, so a lot of heat loss occurs in the magnetic pole head, and the heat in the magnetic pole head increases. Due to conduction, the rotor winding 6 and the insulator 51 installed between the rotor winding 6 and the magnetic pole head and body deteriorate.Especially, heat loss during startup occurs in the direction of rotation of the rotor. Since it concentrates on the magnetic pole head on the leading side of rotation, it damages the insulator installed between the magnetic pole head on the leading side of rotation and the rotor winding 6.

In order to increase the heat capacity during startup and reduce the thermal influence on the rotor winding 6 and the insulator 5, it is necessary to increase the size of the magnetic pole head, which has the disadvantage of increasing the size of the motor.

[Purpose of the invention]

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a salient pole-shaped block magnetic pole rotor that can alleviate thermal effects during startup and prevent damage to windings, insulators, etc. .

[Summary of the invention]

In order to achieve the above object in the salient pole type block magnetic pole rotor of the present invention, a buried material with excellent electrical conductivity and thermal conductivity is provided in a portion of the magnetic pole head that is deeper than the portion where the eddy current is significantly large. The magnetic pole head is buried in a state where heat conduction between the magnetic body and the magnetic body is good.

[Embodiment of the Invention] An embodiment of the present invention will be described with reference to FIGS. 4 and 5. Components that are the same as those in the prior art are designated by the same reference numerals and description thereof will be omitted.

A groove 7 is provided in the block magnetic pole head 4, and an electrically conductive and thermally conductive member 8 made of copper or the like is placed in the groove 7. The method of fixing the electrically conductive and thermally conductive member 8 is to fix the magnetic pole head 4 (by two-heat fitting or magnetic material 9) in order to provide heat insulation and to prevent gaps from interfering with the passage of magnetic flux.

The material of the magnetic pole head 4 and the starting method (=Therefore, the starting method is slightly different, but it is possible to self-start at commercial frequency a synchronous motor equipped with a salient pole block magnetic pole rotor of the present invention using a member made of high tensile steel for the magnetic pole head 4. In this case, the magnetic flux penetration depth at each slip during startup is as shown in the table below (2).If we consider the heat conduction of heat loss due to magnetic flux concentration, the layer where heat is concentrated in the magnetic pole head during startup is the magnetic pole surface. Since the range is more spread out, it is preferable to embed a conductive and thermally conductive member with a length of 10 mm in the middle part of the heat loss generation layer, for example, about 3 mm below the surface of the magnetic pole head 4. The number and size of the electrically conductive and thermally conductive members shall be taken into consideration so as to sufficiently absorb the heat loss that occurs at the magnetic pole head during startup and conduct it to the magnetic pole body.

In the salient pole-shaped block magnetic pole rotor constructed in this way, the part from the surface of the starting magnetic pole head 4 to the penetration depth f''' shown in Table 1 (where the two magnetic fluxes are V-, and the eddy current This causes heat loss, and the resulting heat generation causes the magnetic flux concentrated portion to reach a high temperature.

At this time, since the thermal conductivity of the electrically conductive thermally conductive member is ten times higher than that of the magnetic pole head 4, the electrically conductive member 9 buried below the intermediate layer where heat loss occurs is heated. Due to the conductive action, heat is further conducted to the lower part, and the heat capacity at the time of startup can be expanded. The start-up temperature distributions of the salient pole type block magnetic pole rotor according to the conventional structure and the salient pole type block magnetic pole rotor of the present invention are shown in FIG. 6. This prevents a local temperature rise, which has the effect of mitigating the thermal effect on the insulator 5, which is weaker in heat resistance than steel or copper, and the relationship between the rotor winding 6 and the rotor winding 6° and the magnetic pole part. (- Damage to the installed insulator 5 can be prevented.

In addition, the magnetic flux at the initial stage of startup is as shown in Table 1 above.
Torque is generated by the eddy current concentrated on the surface of the magnetic pole head 4, but as the startup progresses, the magnetic flux penetrates into the inside of the magnetic pole head 4 and the electrically conductive and thermally conductive member 8 embedded in the magnetic pole head 4 is generated.
Inside (2) Inducing eddy current (2) Generating torque, torque 1 = due to the eddy current action on the surface of the magnetic pole head 4
By superimposing them, the torque increases rapidly, which has the effect of making synchronization easier. In other words, member 8 produces an effect similar to that of a starting winding. FIG. 7 shows the speed-torque characteristics as described above. In other words, the torque characteristic (■) in the synchronous motor period with a starting winding is superimposed on the torque characteristic of the conventional lump magnetic pole type synchronous motor as shown in the characteristic (■) in Figure 7 (from the second point, the initial torque at startup and the synchronous It becomes possible to realize an electric motor having ideal starting torque characteristics (2) with large torque at the time of rush.

Other embodiments of the present invention are shown in FIGS. 8, 9 and 10 (
Show two.

The same effect as in the above embodiment can be obtained even if the electrically conductive and thermally conductive member 8 has an inverted trapezoid shape as shown in FIG. It is possible to facilitate heat conduction during startup and further improve torque characteristics during synchronization entry.

Alternatively, as shown in FIG. 9, it is possible to bury an electrically conductive and thermally conductive member 8 having a circular cross-sectional shape. The stress strength of the magnetic pole head 4 against rotational centrifugal force can be improved.

Furthermore, as shown in FIG. 10, electrically conductive and thermally conductive members 10 and 11 of different sizes can be embedded in the rotation advance side and the rotation delay side (secondarily, the same effect as the above-mentioned present invention can be obtained, and Heat concentration on the rotation advancing side where heat loss is concentrated can be alleviated.

〔Effect of the invention〕

As described above, in the present invention, it is possible to alleviate the influence of conduction in the middle part of the heat loss generation layer due to magnetic flux penetration during startup of the rotor pole head, expand the startup heat capacity, and improve the torque characteristics. It is possible to realize a compact and lightweight block magnetic pole type synchronous motor.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a conventional block magnetic pole type synchronous motor;
3 is a sectional view of the magnetic pole of FIG. 2, FIG. 4 is a perspective view of a rotor according to an embodiment of the present invention, and FIG. A cross-sectional view of the magnetic poles, FIG. 6 is a startup temperature distribution diagram of a salient pole block magnetic pole rotor, FIG. 7 is a speed-torque characteristic diagram of a synchronous motor, FIG. 8, FIG. 9, and FIG.
Figure o is a sectional view of a magnetic pole according to another embodiment. 3...Magnetic pole body 4...Magnetic pole head 5...Insulator 6...Rotor winding 7...Groove
8...Electrically conductive thermally conductive member (7317) Agent Patent attorney Noriyuki Chika (and 1 other person) Figure 1/ Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 (O-) Figure 6 (number) of the present invention) Figure 7 Shallow Figure 8 Figure 9 Figure 10 Procedural amendment (method) Showa 5, 3, 'f +) Director General of the Japan Patent Office
Tono 1. Indication of the case Patent application No. 182193/1982 28 Name of the invention Salient pole type block magnetic pole rotor 3 Relationship to the case of @Correct person Patent applicant (307) Tokyo Shibaura Electric Co., Ltd. 4, Agent 1-1-6 Uchisaiwai-cho, Chiyoda-ku, Tokyo 100 Written amendment to the above procedures (voluntary) 115 points, 3. 'i5 ''' Commissioner of the Japan Patent Office 1, Indication of the case Japanese Patent Application No. 57-182193 2 Name of the invention Salient pole type block magnetic pole rotor 3, Amendment 1 Relationship with the case Patent applicant (307 ) Tokyo Shibaura Electric Co., Ltd. 4, Agent Address: 1-1-6 Uchisaiwai-cho, Chiyoda-ku, Tokyo 100 J + On page 5, line 17 of the specification subject to amendment, the phrase ``as shown. Here, FIG. 6+a+ shows the temperature distribution according to the conventional structure, and FIG. 6(b) shows the temperature distribution according to the structure of the present invention. that's all

Claims (1)

[Scope of Claims] (1) In a rotor with salient pole-shaped lumpy magnetic poles having a rotating shaft (=a lump-like magnetic material attached to the rotor and a winding wound around the magnetic material, the head of the magnetic material is A buried material having excellent electrical conductivity and thermal conductivity is buried in a part deeper than a part where the eddy current is significantly large at the time of start-up in a state where heat conduction between the material and the magnetic body is good. Pole-shaped blocky magnetic pole rotor. 2. The salient pole-shaped blocky magnetic pole rotor according to claim 1, wherein the embedded material is larger on the rotation advance side of the magnetic pole than on the rotation lag side.