JPH0568179B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Field of 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. [Prior Art] As described in Japanese Utility Model Publication No. 27-9421, the rotor of a conventional rotating electric machine is described in, for example, FIG. 3. As shown in FIG. A coil holder 4 is arranged on the inner circumference of the rotor coil 3, and the outer side of the rotor coil 3 is fixed with a coil support member 6. That is, the rotor coil 3 in the vicinity of the rotor core 2 is brought into contact with the core presser 13, or as described in Publication of Utility Model Publication No. 37-3503,
There are some that extend the coil holder (cylindrical ring part) close to the rotor core to receive the inner circumference of the coil. However, when such a rotor is applied to an alternating current machine equipped with a wound rotor coil, such as a water turbine generator, large currents and high voltages are continuously passed through the rotor coil, making it difficult to insulate the coil. However, it is necessary to have a highly reliable structure. 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 δ ₁ 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, the centrifugal force F 2 acting on the rotor core ₂ increases in proportion to the rotation speed, as shown in Figure 5, so that an additional step of δ ₂ occurs in the coil on the rotor core 2 side. , the step difference δ ₃ becomes even larger, and the stress at the coil bending portions a and b further increases. (The centrifugal force F ₁ acting on the coil end is suppressed by the coil support member up to a certain rotational speed, so the coil end does not extend toward the outer circumference.) As a method to solve the above problem, first Firstly, as described in Japanese Utility Model No. 18-349223, a method in which the coil holder is divided into parts applies the centrifugal force of the coil holder to the coil support member via the coil, thereby reducing the level difference in the coil during operation. However, in water turbine generators, etc., the coil support member is held in place against the centrifugal force of the coil holder even at the maximum rotational speed during a transient period, so the coil support member becomes extremely large and becomes extremely large. This results in an inefficient machine. Moreover, the surface pressure on the inner peripheral portion of the coil becomes extremely large, which naturally limits the rotational speed and dimensions. Alternatively, by lowering the rigidity of the coil support member,
It is possible to reduce the coil steps δ ₁ and δ ₃ , but this may be a design issue due to issues such as ensuring contact between the coil support member and the outer circumferential surface of the coil during assembly, and ensuring contact between the coil holder and the inner circumferential surface of the coil during operation. Also, the manufacturing process becomes complicated and difficult to realize. As a second method, as described in Utility Model Application Laid-open No. 61-41347 (however, this invention relates to stator coils), a method can be considered in which the distance between the core and the coil contact surface is increased to alleviate the stress caused by the step difference. . (In other words, the method may be replaced by increasing the l dimension in FIGS. 4 and 5.) However, even this method is difficult to apply to large-capacity or high-speed machines.
That is, to explain with reference to FIGS. 6 and 7, first, as shown in FIG. 6, notches C ₁ ,
C ₂ is provided, and the coil step difference δ ₃ is larger than the air gap l ₁
However, during actual operation, the air gap is l ₀ which is smaller than l ₁ , and even if the notches C ₁ and C ₂ are made larger, the stress will not be alleviated. . In _other words, the air gap l ₀ becomes a constant value depending on the elastic modulus of the coil and the amount of deformation, and is no longer affected by the size of the notch after a certain dimension. There is no need to install a notch. That is, if the above-mentioned FIG. 7 is further modeled and explained as shown in FIG. 8, the critical gap l ₀ and the coil stress σ are given by the following equation. Incidentally, FIG. 8 shows a combination of the initial displacement δ ₁ (see FIG. 4) at the time of stop and the centrifugal force of the coil during operation.

[ka]

[Problem that the invention seeks to solve]

In the rotor of conventional rotating electric machines as described above, especially when trying to increase the capacity and speed, the amount of deformation of the end of the coil is limited due to constraints on the strength of the rotor coil. There was a problem that it was difficult to increase the capacity and speed. Therefore, the purpose of the present invention is to solve these problems and increase the capacity and speed of the rotor, and
It is an object of the present invention to provide a rotor for a rotating electrical machine that is highly reliable in terms of the strength and insulation of the rotor coil and is suitable as a rotor for a water turbine generator or the like. [Means for Solving the Problems] In order to achieve this object, the present invention provides a method in which a cylindrical coil holder is arranged on the inner periphery of the rotor coil; It is characterized in that the annular ring is separated in the radial direction, and either the inner or outer ring of the separated ring is divided into segments and connected to the other annular ring. [Function] When the coil support member is installed, the coil clamping force of the coil support member is transmitted to the rotating shaft through the radial split ring (outer/inner) on the inner circumference of the coil via the coil and coil holder. . 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] An example of the present invention will be described with reference to FIGS. 1 and 2. In FIG. 1, a rotor core 2 placed around a rotating shaft 1 is fixed by core holders 8 and 9,
Segmented core retainer 9 divided into four parts (see Figure 2)
The outer periphery of the coil holder 4 is connected to the inner periphery of the lower surface of the cylindrical coil receiver 4 by shrink fitting. In addition, iron core presser 9
The inner periphery of the iron core holder 8 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.
A rotor coil 3 is arranged on the outer periphery of this coil holder 4 together with insulators 5, 7, and 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 electric machine as described above, the compression amount of the rotor coil 3 toward the inner diameter side when the coil support member 6 is installed is equalized by the cylindrical coil receiver 4 and is equalized by the core pressers 8 and 9. Therefore, contact between the outer peripheries of the coil support member 6 and the coil 3 at the time of initial setting is ensured. In addition, since the compressive force caused by the coil support member 6 can be shared by increasing the rigidity of the annular core holder 8, the coil holder 4, which is generally made of non-magnetic steel, can be made relatively thin.
It also has the effect of being economical. Next, during operation, since the centrifugal force of the core holder 9 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 unreasonable stress is not 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 receiver 4,
Not only does it press the stepped part of the coil most effectively, it also serves as a core holder, reducing the number of parts. In addition, in this example, the coil receiver 4 and the core holder 9 are connected by shrink fit, so that
It ensures contact, prevents eccentricity, and reliably transmits rotational torque. [Effects of the Invention] As described above, the present invention reliably maintains this force when the coil support member is fixed due to the action of the radial split ring on the inner circumference of the coil receiver, and the segmented split ring during operation. Since the centrifugal force of the rotor gives outward displacement to the coil, it is possible to provide a rotor coil with less deformation of the coil end during stoppage and operation, and it is possible to provide a large-capacity, high-speed rotor. .

[Brief explanation of drawings]

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

Claims (1)

[Claims] 1. A rotor coil attached to a rotor core, an end of the rotor coil fixed from the outside of the rotor coil with a coil support member, and an insulator attached to the inner circumference of the coil. A cylindrical coil holder is arranged through the holder, and an annular ring is arranged on the inner circumference of the holder to connect it to a rotating shaft, a rotor core, or something similar, in which the annular ring is radially separated,
A rotor for a rotating electrical machine, characterized in that either the inner or outer ring of the separated rings is divided into segments and connected to the other annular ring. 2. The rotor of a rotating electrical 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, characterized in that 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.