JPH0419964Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Technical Field of the Invention] This invention relates to rotating electric machines such as turbine generators, and particularly to improvements in support devices for stator winding ends. [Prior art] In general, the causes of vibration in rotating electric machines such as turbine generators can be roughly divided into electromagnetic causes and mechanical causes. The outline of vibration at the stator winding ends will be briefly explained. At the end of a rotating electric machine such as a turbine generator, there is leakage magnetic flux generated from the rotor winding end or stator winding end, and this leakage magnetic flux interlinks with the stator winding end, so it is fixed. Electromagnetic force acts on the ends of the child windings, and this is also a cause of vibrations at the ends of the stator windings. Such electromagnetic force includes a steady electromagnetic force that acts during normal operation, and a transient electromagnetic force that occurs due to a short circuit accident that occurs within a power plant or in a power generation system. In particular, transient electromagnetic force is 10~
It can reach up to 15 times. Therefore, the ends of the stator windings must be firmly fixed and supported so as not to be damaged by vibrations generated by such steady electromagnetic force and transient large electromagnetic force. There is. In particular, in large-capacity generators, a water cooling coil with high cooling efficiency is adopted for the stator winding in order to improve the efficiency of the generator, so the cross-sectional area of the stator winding is smaller than that of small-capacity generators. becomes smaller,
It has become impossible to support the vibrations generated by electromagnetic force with the rigidity of the stator windings alone. Therefore, in such large-capacity generators, a support device for the end of the stator winding is adopted, which strengthens the rigidity of the stator winding by arranging a large insulating ring around the outer circumference of the stator winding. has been done. 1 and 2 show an example of a rotary electric machine such as a turbine generator equipped with a conventional stator winding end support device of this type. The figure is a side view of FIG. 1 viewed from the direction of the arrow. In the figure, reference numeral 1 denotes a frame body consisting of a stator frame, on which a plurality of protrusions (not shown) of a predetermined length are formed, each having an inner circumferential surface of a predetermined size. 2 is a stator core whose outer peripheral surface is fitted and supported by the inner peripheral surface of a plurality of protrusions of the frame body 1; 3 is a stator winding wound around this stator core 2; 3a, 3;
b is the lower and upper stator winding ends protruding from the respective end faces of the stator core 2 of the stator winding 3, and 3c and 3d are the protruding ends of the respective ends 3a and 3b. Reference numeral 4 indicates a pair of insulating rings (only one of which is shown in the figure) provided on the outer periphery of the end portion 3a of the stator winding at the lower port, and 5 indicates the stator ports at the upper and lower ports. A spacing piece (the figure shows only one) is placed between the ends 3a and 3b of the winding, and 6 is a holding plate placed on the inner circumferential side of the end 3b of the stator winding at the upper opening. (The figure shows only one side.) This presser plate 6,
The spacing piece 5 and the insulating ring 4 are firmly fastened together using bolts or tie strings (not shown).
The entire end portion 7 of the stator winding is firmly and integrally fixed. Supports 8 project from each end face of the stator core 2 and are designed to support the entire end 7 of the stator winding. Reference numeral 9 designates a phase lead whose one end is electrically connected to the radial outer circumferential side of each of the leads 3c and 3d, and 10 represents a phase ring connected to the other end of this phase lead 9. ,
It is formed in the circumferential direction with respect to the openings 3c and 3d. Reference numeral 11 denotes a plurality of pairs of phase ring supports having recesses 11a corresponding to the outer peripheral shape of the phase ring 10, which hold the phase ring 10 in each recess 11a and are arranged at approximately equal intervals around the outer periphery of the insulating ring 4. and are connected to the outer peripheral surface of the insulating ring 4 with fastening members such as bolts. Terminals 12 are connected to the openings 3c and 3d of the stator winding 3 via the phase rings 9 and 10, and are disposed on the outer periphery of the frame 1. A conventional supporting device for the stator winding end of a rotating electric machine such as a turbine generator is constructed as described above, and in particular, the support device for the end of the stator winding of a rotating electric machine such as a turbine generator is constructed as described above. section is not supported at all. Therefore, the natural frequency fn of the phase lead 9 expressed by the following equation is relatively low, and there is a possibility that it resonates with the excitation frequency of 120 Hz of the electromagnetic force, causing excessive vibration and causing the phase lead 9 to become damaged due to repeated stress. However, it had the disadvantage of causing fatigue rupture.

[Summary of the idea]

This invention was made in order to eliminate such drawbacks, and it is possible to connect the central part of the phase lead whose both ends are connected to the lead and the phase ring, and the part of the insulating ring opposite to the central part of the phase lead. one of at least a pair of insulating members is inserted into the insulating member, the phase lead is sandwiched between the other insulating member, the inserted insulating member is fixed to the insulating ring with a fastening member, and the center portion of the phase lead is insulated. By supporting the phase lead with an insulating ring via a member, the phase lead insulation properties are not reduced, and the length between the support points of the phase lead can be reduced to approximately half of that of conventional devices. The natural frequency of the phase lead is shortened to the excitation frequency of the electromagnetic force.
We propose a support device for the stator winding end of a rotating electric machine that is sufficiently larger than 120Hz to eliminate the possibility of phase lead resonance, suppress phase lead vibration, and prevent the phase lead from fatigue breaking due to vibration. It is something to do. [Embodiment of the invention] Figs. 3 to 5 show an embodiment of this invention, in which Fig. 3 is a partially sectional front view, Fig. 4 is a side view of Fig. 3 viewed from the arrow direction, FIG. 5 is a perspective view of a pair of insulating members, FIG. 5 is a perspective view of the first insulating member, and FIG. 5 is a perspective view of the second insulating member. In the figure, reference numeral 13 has one end surface in contact with the outer end surface of the insulating ring 4, and the engagement groove 1 of the phase lead 9 in the center of the other end surface.
3a is a pair of quadrangular prism-shaped first insulating members, and 13b is an engagement groove 1 of this first insulating member 13.
A pair of through holes 14 formed at equal intervals from the axial center of 3a are connected to the other end surface of the first insulating member 13, and are approximately in the axial direction of the phase lead 9 inserted into the connecting groove 13a. The second insulating member is a pair of second insulating members whose center portions are inserted into the engagement grooves 13a, and four through holes 14a are formed to face each pair of through holes 13b. Note that the first insulating member 13 and the second insulating member 14 constitute a pair of insulating members 15. Reference numerals 16 denote four female screws (see FIG. A fastening member consisting of four bolts each formed of a non-magnetic metal or an insulating material screwed to the (not shown), which fastens and connects each pair of insulating members 15 to the insulating ring 4, and also connects the axis of the phase lead 9. The engagement groove 13a is located approximately at the center of the direction.
They are designed to be clipped inside. Note that the reason why the fastening member 16 is made of a nonmagnetic metal or an insulating material is to suppress heat generation of the rotating electric machine due to eddy current. The rest of the configuration is the same as that of a conventional support device for the stator winding end of a rotating electrical machine such as a turbine generator, so a description thereof will be omitted. With this structure, the natural frequency fn of the phase lead 9 is the same as the above equation, i.e.

[Effect of idea]

As explained above, this invention has a structure in which the approximately central portion of the phase lead in the axial direction is held between at least a pair of insulating members, and the held insulating members are connected to an insulating ring by a fastening member. This has an excellent effect in that the natural frequency of the phase lead can be made sufficiently higher than the excitation frequency of the electromagnetic force, and fatigue rupture due to resonance of the phase lead can be prevented.
Further, since the fastening member is made of a non-magnetic metal or an insulating material, it is possible to suppress heat generation of the rotating electric machine due to eddy current.

[Brief explanation of the drawing]

Fig. 1 is a partially sectional front view of a rotating electric machine equipped with a conventional stator winding end support device, Fig. 2 is a side view of Fig. 1, and Fig. 3 is a portion showing an embodiment of this invention. 4 is a side view of FIG. 3, FIG. 5 is a perspective view of a pair of insulating members, and FIGS. 6 and 7 are enlarged plan views of insulating members in other embodiments of this invention, respectively. It is. In the figure, 1 is a frame, 2 is a stator core, 3 is a stator winding, 3a and 3b are ends of the stator winding, 4
1 is an insulating ring, 9 is a phase lead, 10 is a phase ring, 13, 13a, 13b, 13c are first insulating members, 14 is a second insulating member, 15 is a pair of insulating members, and 16 is a fastening member. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims for Utility Model Registration] (1) A frame, a stator core surrounded and supported by this frame, a stator winding wound around this stator core, and an end portion of this stator winding. An insulating ring is disposed on the outer circumference of the insulating ring to support the stator winding ends and constitutes a support device for the winding ends. A rotating electric machine comprising a supported phase ring and a phase lead having both ends coupled to an end of a stator winding end and the phase ring for electrically connecting the phase ring and the stator winding. In the stator, at least one pair of insulating members sandwich the center portions of one end of the phase lead connected to the stator winding and the other end connected to the phase ring, and the pair of insulating members are connected to the insulating ring. A stator for a rotating electric machine, characterized in that a phase lead is supported by being fixed to a surface facing the center portion of the phase lead with a fastening member. (2) At least one pair of insulating members includes a first insulating member whose one end surface is in contact with the outer end surface of the insulating ring and which has an engagement groove for the phase lead on the other end surface, and a first insulating member whose other end surface is in contact with the outer end surface of the insulating ring. A stator for a rotating electric machine according to claim 1, characterized in that the stator is comprised of a second insulating member that is coupled to hold the phase lead in the engagement groove. (3) A stator for a rotating electric machine according to claim 1 or 2, wherein the fastening member is a bolt made of non-magnetic metal. (4) A stator for a rotating electrical machine according to claim 1 or 2, wherein the fastening member is a bolt made of an insulating material.