JPS63310342A - Rotor of rotating electric machine - Google Patents

Abstract

PURPOSE:To reduce the deformation amount at the edge of a coil, by arranging a cylindrical coil step on the inside circumference of coil and by separating an annular ring radially which is arranged on the inside circumference of this coil step. CONSTITUTION:A rotor core 2 arranged around a rotating shaft 1 is secured with core caps 8 and 9. The rotor core 2 is then coupled to the inside circumference of the under surface of a cylindrical coil step 4 by shrinkage fitting on the outside circumference of the quartered segment of a core cap 9. The inside circumference of the core cap 9 is brought into contact with the outside circumference of the core cap 8 and is coupled each other with axially anchoring projection and recession. On the outside circumference of this coil step 4 a rotor coil 3 is arranged along with insulations 5, 7 and 12 and secured with a binding wire or a cylindrical coil supporting member 6 so as to give compressive displacement to the edge of the coil. The deformation amount at the edge of coil will thereby be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a rotor for a rotating electric machine, and particularly to a rotor for a large-capacity rotating electric machine in which a rotor coil is mounted on a rotor core.

[Conventional technology]

As described in Japanese Utility Model Publication No. 27-9421, the rotor of a conventional rotating electrical machine has a rotor core 2, for example, as shown in FIG.
A coil holder 4 fixed by an iron core holder 13 and connected to a rotating shaft 1 is arranged on the inner circumference of the rotor coil 3, and the outer side of the rotor coil 3 is fixed by a coil support member 6. In other words, the vicinity of the rotor core 2 of the rotor coil 3 is brought into contact with the core holder 13, or the coil holder (cylindrical ring part) is extended to the vicinity of the rotor core as described in Japanese Utility Model Publication No. 37-3503. There are some that receive the inner circumference of the coil.

However, when applying such a rotor to an alternating current machine equipped with a wound rotor coil, such as a water turbine generator,
Since this rotor coil is continuously supplied with a large current and high voltage, it is necessary to have a structure that is highly reliable in terms of coil insulation. In addition, because the rotor of a water turbine generator needs to have a flywheel effect, the rotor is larger than that of an induction motor or DC motor of the same capacity, making it impossible to increase the main engine capacity. There are drawbacks. That is, to explain this with reference to FIGS. 4 and 5. Although FIG. 4 shows the main engine stopped state, the coil support member 6 is firmly attached to withstand the centrifugal force of the end of the coil during rotation (the binding wire (winding, cylindrical ring shrink fitting, etc. are common methods), a step δ1 naturally occurs between the rotor coil 3 and the coil support member 6 side in the rotor core 2. Next, when the rotor core 2 is rotated in this state, as shown in Fig. 5, it acts on the rotor core 2 (the centrifugal force F2 increases in proportion to the rotational speed, so an additional step of δ2 occurs in the coil on the rotor core 2 side, The step difference δ becomes even larger, and the stress at the coil bending parts a and b further increases. (No side elongation occurs.) As a method to solve the above problem, the first step is to reduce the centrifugal force of the coil holder by using a structure in which the coil holder is divided, as described in Utility Model Application No. 18-349223. It is possible to reduce the level difference in the coil during operation by adding the coil to the coil support member through the coil, but in water turbine generators etc.
Since the coil support member is held in a predetermined position against the centrifugal force of the coil receiver even at the maximum rotational speed during a transient period, the coil support member becomes extremely large, resulting in a very inefficient machine. Moreover, the surface pressure on the inner circumference of the coil becomes extremely large, which naturally limits the rotational speed and dimensions. Alternatively, reducing the rigidity of the coil support member to reduce the coil step difference δ and δ3 may be considered, but it is also possible to ensure contact between the coil support member and the outer circumferential surface of the coil during assembly, and between the coil holder and the inner circumference of the coil during operation. Due to problems such as securing surface contact, the design and manufacturing are complicated and difficult to realize.

As a second method, as described in Utility Model Application No. 61-41347 (however, this invention relates to stator coils), there is a method of increasing the distance between the iron core and the coil contact surface to alleviate the stress caused by the step difference. It will be done. (In other words, the method may be replaced by the method of increasing the dimension E in FIGS. 4 and 5.) However, even this method is difficult to apply to large-capacity machines or high-speed machines. That is, to explain with reference to FIGS. 6 and 7, first, as shown in FIG. 6, a notch C is formed on the rotor core 2 side.
,,C.

Provide a coil step δ, and create a gap! greater than i.

However, during actual operation, the air gap is smaller than 2.
o, and even if the notches C+ and Cz are made larger, the stress will not be alleviated. In other words, the air gap 10 becomes a constant value depending on the elastic modulus and deformation of the coil, and is no longer affected by the size of the notch after a certain dimension, so if Ito-1 is set, the notch cannot be installed in the rotor core. No longer needed. That is, if the above-mentioned Fig. 7 is further modeled and explained as shown in Fig. 8, the critical gap 2° and the coil stress σ are given by the following equation. Incidentally, FIG. 8 shows a combination of the initial displacement δ1 (see FIG. 4) at the time of stop and the coil centrifugal force during operation.

In addition, explanations of the symbols and units of the above formulas (1) and (2) are shown below.

ω: Centrifugal force per unit length of coil (kg/+u+) δ: Coil step (n) E: Coil) Lt elastic modulus (kg/m++z)
■ = Coil cross-sectional moment of inertia (Il1m') h: Coil height (m+a) 10: Coil deformation limit dimension (IIIm) σ: Coil stress
(kg/IIIm") As explained above, in the conventional technology, in order to increase the capacity and speed of a rotor in which a rotor coil is attached to a rotor core, coil steps (
It can be seen that it is necessary to minimize the amount of deformation at the end of the coil.

[Problem that the invention seeks to solve]

In the rotor of the conventional rotating electric machine mentioned above, especially when trying to increase the capacity and speed, the strength of the rotor coil limits the amount of deformation at the end of the coil. The problem was that it was difficult to increase capacity and speed.

Therefore, an object of the present invention is to solve these problems and increase the capacity and speed of the rotor, and also to provide a rotor for a water turbine generator, etc., which has high reliability in terms of the strength and insulation of the rotor coil. The purpose of the present invention is to provide a rotor for a rotating electric machine, which is suitable for use as a rotor.

[Means for solving problems]

In order to achieve this object, the present invention arranges a cylindrical coil holder on the inner periphery of the rotor coil, and separates the annular ring arranged on the inner periphery of the coil holder in the radial direction. The ring is characterized in that either the inner or outer ring is divided into segments and connected to the other annular ring.

[For production]

When the coil support member is attached, the coil clamping force of the coil support member is transmitted to the rotating shaft through the radial division ring (outer/inner) on the inner circumference of the coil via the coil and the coil receiver. Next, during rated operation of the main engine, in addition to the centrifugal force at the end of the coil, the centrifugal force from the segment-shaped split ring is applied to the inside of the coil receiver. Since the coil receiver is cylindrical, the centrifugal force of the ring is added to the hoop force of the coil receiver and is transmitted to the coil as an even outward displacement. Therefore, the displacement approximately corresponds to the outward displacement due to the centrifugal force of the rotor core, and the step of the coil hardly changes.

In addition, during transient operation of the main engine (for example, when the rotational speed is twice that of rated operation), the centrifugal force of the segmented split ring can be stopped by the other split annular ring, so the coil support member Do not apply excessive force to the

This allows the coil support member to be manufactured relatively thin and compact.

〔Example〕

Embodiments of the present invention will be described with reference to FIGS. 1 and 2.

In Fig. 1, a rotor core 2 arranged around a rotating shaft 1 is fixed by core holders 8 and 9, and a cylindrical coil receiver is attached to the outer periphery of a segment-shaped core holder 9 divided into four parts (see Fig. 2). It is connected to the inner periphery of the lower surface of metal 4 by shrink fitting. Further, the inner periphery of the core holder 9 and the outer periphery of the core holder 8 are brought into contact with each other and engaged by projections and depressions that lock in the axial direction.

The rotor coil 3 is placed on the outer periphery of the coil holder 4 together with an insulator 5, 7, 12, and is fixed to the end of the coil with a binding wire or a cylindrical coil support member 6 so as to apply compressive displacement. .

According to the rotor of the rotating electrical machine as described above, the compression amount of the rotor coil 3 toward the inner diameter side when the coil support member 6 is attached is equalized by the cylindrical coil receiver 4 and is equalized by the core presser 8.9. Because the coil support member 6 is retained at the time of initial setting,
The contact with the outer periphery of the coil 3 is ensured. In addition, the compressive force caused by the coil support member 6 can be shared by increasing the rigidity of the annular core holder 8, so the coil holder 4, which generally uses non-magnetic steel, can be made relatively thin, making it economical. There is also this effect. Next, when driving, use the iron core presser 9.
Since the centrifugal force increases in proportion to the rotational speed, this force is applied to the cylindrical coil receiver 4 as internal pressure. Since the coil holder 4 spreads outward evenly, a uniform force is applied to the coil 3, making it possible to follow the expansion of the coil in the outer circumferential direction on the rotor core 2 side, and suppressing changes in the level difference of the coil.

Therefore, since no unreasonable stress is generated in the coil, high reliability can be obtained in terms of insulation performance and strength. In addition, in a transient operating state, the centrifugal force of the core holder 9 becomes strong, and even if a force is exerted on the core holder 9 to move the core holder 9 greatly toward the outer periphery, it is retained by the annular core holder 8, so even if the rotation speed exceeds a certain rotation speed, An excessive load on the coil support member 6 is alleviated, and the coil support member 6 can be made thinner and more compact. Furthermore, since the core holder 9 is placed on the rotor core 2 side of the coil holder 4, it can most effectively press the stepped portion of the coil, and also serves as a core holder, reducing the number of parts. . In addition, in this example, the coil receiver 4 and the core presser 9 are connected by shrink fit, thereby ensuring contact, preventing eccentricity, and reliably transmitting rotational torque.

〔Effect of the invention〕

As described above, in the present invention, the force is reliably maintained when the coil support member is fixed by the action of the radial split ring on the inner circumference of the coil receiver, and during operation, the centrifugal force of the segmented split ring is used to securely hold the coil support member. Since an outward displacement can be applied to the rotor, it is possible to provide a rotor coil with a small amount of deformation at the end of the coil during stoppage and during operation, and a large-capacity, high-speed rotor can be provided.

[Brief explanation of drawings]

1 and 2 show embodiments of the present invention.
The figure is a longitudinal sectional view of the rotor, Figure 2 is a plan view of Figure 1 viewed from A-A, Figures 3 to 8 show conventional examples, and Figure 3 is a diagram of the rotor. 4 and 5 are detailed views of the P section in FIG. 3, and FIGS. 6 and 7 are another conventional example similar to the detailed view of the P section in FIG. 3. The figure is a model of FIGS. 6 and 7. DESCRIPTION OF SYMBOLS 1... Rotating shaft, 2... Rotor core, 3... Rotor coil, 4... Coil holder, 6... Coil support member, 8... Iron core holder (annular ring), 9... Iron core holder (segment division).

Claims (1)

[Claims] 1. A rotor coil attached to the rotor core, an end of the rotor coil fixed from the outside of the rotor coil with a coil support member, and an insulating member attached to the inner circumference of the coil. In a device in which a cylindrical coil receiver is arranged through an object, and an annular ring is arranged on the inner circumference of the receiver and connected to a rotating shaft, a rotor core, or a similar object, the annular ring A rotor for a rotating electric machine, characterized in that the inner ring or the outer ring of the separated ring is divided into segments and connected to the other annular ring. 2. The rotor of a rotating electric machine according to claim 1, wherein the axial position of the ring divided into segments is arranged on the rotor core side of the coil receiver. 3. A rotor for a rotating electric machine according to claim 1, wherein a separate annular ring is installed to press down on the rotor core. 4. The rotor of a rotating electric machine according to claim 1, wherein a coil holder is connected to the outer ring of the separated annular ring by tight fit.