JPH0226453B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air gap winding rotating electrical machine in which a stator coil is mounted on the slotless inner peripheral portion of a magnetic shield on the stator side.

In recent years, in rotating electric machines, due to the increase in unit capacity and the development of superconducting rotating electric machines, air gear winding, in which a stator coil is installed without a slot on the stator side, has been adopted.

The air gear winding rotating electric machine is characterized by the fact that there are no teeth on the stator core, so the stator coil is placed in the air gap to increase the space factor, making effective use of the empty space. For example, the magnetic flux density of the part can be increased. However, the lack of slots makes it difficult to retain the stator coils.

This type of air gap winding rotary electric machine according to the prior art is shown in FIGS. 1 and 2 as a longitudinal sectional view and an enlarged front sectional view of the air gap winding portion. Reference numeral 1 denotes a magnetic shield formed into an integral cylindrical shape by laminating a large number of silicon steel plates, etc., which is held at both ends by end holding plates 2, and is held within a stator frame (not shown). The inner circumferential surface of the magnetic shield 1 has no slot. 3 is a thin insulating inner cylinder shaped to surround the outer circumference of the rotor 9 at intervals, and is made of, for example, epoxy resin glass fiber material or epoxy resin glass cloth material, and is wound into a cylindrical shape. be. Reference numeral 4 denotes a large number of stator coils disposed on the outer circumferential side of the insulating inner cylinder 3, which shows the case of two-layer winding, and consists of an upper opening 4a and a lower opening 4b. Reference numeral 5 denotes an insulating press plate applied to the outer periphery of each stator coil 4, which is divided into a plurality of parts in the circumferential direction, and is made of, for example, an epoxy resin glass cloth laminate. 6 is the upper opening 4a
and the lower opening 4b, 7 is an insulating spacing piece inserted between each stator coil 4, and 8 is an axially insulating plate between the inner peripheral part of the magnetic shield 1 and the insulating holding plate 5. A pair of tapered key-shaped wedges are driven in, and are divided into two in the thickness direction, with both joining surfaces forming a slope. In the example shown in the figure, the wedges are divided into two sets in the axial direction, and It is arranged around the entire circumference. These wedges 8 are made of an insulating material with high mechanical strength, and are driven in the axial direction to generate compressive force in the radial direction, thereby firmly pressing and fixing the stator coil 4.

The stator coil 4 has both ends extending outward from the end of the magnetic shield 1 and extending in the circumferential direction, and has an upper opening 1a.
and the lower port 1b are connected or connected to a connecting line. When energized, an electromagnetic force is generated at the end of the stator coil 4, although it is smaller than that at the straight portion.

If the ends of the stator coil 4 are not sufficiently supported in the radial direction, the electromagnetic force causes abnormal vibrations in the coil, which may damage the coil holder.

Further, if a three-phase sudden short circuit accident occurs, the four ends of the stator coil will receive excessive electromagnetic force, and there is a risk that it will be damaged in an instant.

This invention was made to solve the above-mentioned problems, and a coil holding member having an L-shaped cross section when viewed from the circumferential direction is attached to an end holding plate holding down a magnetic shield. A wedge is driven in the axial direction between the axial side of the stator coil and the end side of the insulating holding plate that covers the outer periphery of the stator coil, and the air is firmly held by pressing the end of the stator coil in the radial direction. The purpose is to provide a gear winding rotating electric machine.

3 and 4 are a longitudinal cross-sectional view and a front view of an air gear winding part, showing an air gear winding rotating electrical machine according to an embodiment of the present invention; is the same as that of the prior art described above. Reference numeral 11 denotes a plurality of coil holding members each having an L-shaped cross section when viewed from the circumferential direction, and are made of a non-magnetic metal material such as stainless steel. It is attached to the insulation holding plate 5 with a radial gap on one axial side. 13 is a coil holding member 11 and an insulating holding plate 5
A pair of tapered key-shaped wedges driven in the axial direction between the , made of epoxy resin glass cloth laminate. These wedges are provided with retaining means (not shown) at their outer ends.

The coil holding member 11 is divided into a plurality of pieces in the circumferential direction. This is to prevent eddy currents due to leakage magnetic flux.

Further, the wedge 13 is made of an insulating material to prevent eddy current loss and to strengthen ground insulation.

In this way, the wedge 13 is driven between the coil holding member 11 and the insulating holding plate 5, and the stator coil 4
By pressing the end portions in the radial direction and firmly fixing them, they can withstand large electromagnetic forces and can be operated without any problems.

In the above embodiment, the wedges 8 are used to fix the stator coil portion to the magnetic shield 1, but other fixing means that press in the radial direction can also be used.

As described above, according to the present invention, the L-shaped coil holding member is attached to the end holding plate of the magnetic shield, and the insulating holding plate that covers the outer periphery of the stator coil and the protruding axial side of the coil holding member are connected to each other. During this process, the wedges are driven in the axial direction, so the ends of the stator coils are pressed in the radial direction and held firmly, improving reliability.

[Brief explanation of drawings]

FIG. 1 is a longitudinal cross-sectional view of an air gear winding portion showing an air gear winding rotary electric machine according to the prior art, FIG. 2 is a cross-sectional view taken along the line - in FIG. 1, and FIG. FIG. 4 is a longitudinal sectional view of an air gap winding section showing an air gap winding rotary electric machine according to one embodiment, and FIG. 4 is a front view of the air gap winding section of FIG. 3. 1...Magnetic shield, 2...End holding plate, 3...
...Insulating cylinder, 4...Stator coil, 5...Insulating holding plate, 8...Wedge, 11...Coil holding member,
13...It is a wedge at the end. Note that the same reference numerals in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] 1. A plurality of stator coils are arranged on the outer periphery of an insulated inner cylinder, and an assembly consisting of an insulating press plate placed and covered on the outer periphery of these stator coils is inserted into the inner periphery of the magnetic shield, and this magnetic shield is In a rotating electrical machine in which a fixing means for pressing in the radial direction is disposed between the inner circumferential part of the insulating press plate and the outer circumferential part of the insulating holding plate, and the stator coil part is fixed, the cross section L as seen from the circumferential direction
a plurality of coils each having a shape, attached to the end holding plate of the magnetic shield, and arranged such that the lower surface of one side protruding in the axial direction is spaced from the outer circumferential end side of the insulating holding plate; an air gear comprising a holding member, and a plurality of wedges that are driven in the axial direction into the gaps between the insulating holding plate and the coil holding member to press and fix the ends of the stator coils in the radial direction; Winding rotating electric machine.