JPS60176446A - Insulating method of wound conductor - Google Patents

Abstract

PURPOSE:To improve the insulating performance by differentiating the size of the weaving mesh of an insulating tape which contains cure accelerator at between the sides near to and far from a wound conductor, thereby eliminating an air gap in an insulating layer. CONSTITUTION:An insulating tape 6a near a wound conductor has a large cloth mesh, the tape 6a is wound in the prescribed number of turns, an insulating tape 6b having a cloth mesh smaller than the tape 6a is then wound, and an insulating tape 6c having a cloth mesh further smaller than the tape 6b is wound thereon. Thus, the wound conductor formed with the insulating layer in this manner is contained in a resin impregnating unit, and a vacuum impregnation is performed.

Description

Detailed Description of the Invention [Technical field to which the invention pertains] The present invention involves winding an insulating tape containing a curing accelerator for an impregnated resin around a wire-wound conductor, and impregnating the wire-wound conductor with a thermosetting resin under vacuum pressure. A method of insulating a winding conductor by impregnating it by treatment and then heating and curing the thermosetting resin, particularly a method of insulating a stator winding of a high-voltage rotating machine. [Prior art and its problems] Generally, fixing of a high-voltage rotating machine As shown in FIG. 1, the child winding consists of a hexagonal-shaped conductor 1 with C double-wire insulation, and this conductor 1 has a slot portion 2 inserted into the stator core. End part that extends outside the iron core 3. and an outlet portion 4 for connecting the coils.

This conductor 1 is insulated as follows.

That is, a laminated mica tape and a peeled mica insulating tape lined with glass fiber are wrapped around the entire circumference of the conductor 1, and after wiring connections are made, the entire stator is placed in a resin impregnating device and filled with epoxy resin.

Thermosetting resin such as polyester resin is impregnated into the insulation tape by vacuum pressure impregnation process, and finally this stator is placed in a heating curing oven, where the thermosetting resin is heated and hardened to create a fully impregnated insulation system. Insulated.

In this case, the insulating tape is a peel-off mica insulating tape lined with glass fiber, and since the mica layer is already attached to the glass fiber, it has various advantages such as no missing mica pieces and the ability to be machine rolled. ing. However, this insulation method is difficult because the insulating tape contains a hardening accelerator for the impregnated resin (2. During the resin impregnation process, the resin does not penetrate sufficiently into the entire insulating layer, creating voids. It has its drawbacks.

This will be explained with reference to FIG. FIG. 2 shows the overlapping state of the insulating tape 5 of the insulating layer when the insulating tape 5 is wound by half-overlap winding. All the insulating tapes 5 in this insulating layer have the same cross mesh. During the resin impregnation process, most of the resin permeates from the through-layer direction as shown by arrow A, and only a small amount permeates from the along-layer direction as shown by arrow B. Therefore, if the insulating layer is thick, the resin may not penetrate sufficiently to the bottom layer, and the resin may harden while leaving voids.

Although the presence of these voids does not pose much of a problem initially, if the device is operated for a long period of time, there is a risk that the insulation may deteriorate due to partial discharge or the like.

[Purpose of the invention]

In the present invention, the resin permeates into the insulating layer sufficiently, and no voids are formed in the insulating layer.

It is an object of the present invention to provide a method of insulating a winding conductor that can improve insulation performance.

[Key points of the invention]

According to the invention, this object is achieved by changing the size of the fiber mesh of the insulating tape containing the hardening accelerator on the side close to the winding conductor and on the side remote from the winding conductor in an insulation method of the type mentioned at the outset. This is achieved by making a difference in

[Embodiments of the invention]

Next, the present invention will be explained in detail based on the embodiment shown in FIG.

FIG. 3 shows a cloth mesh of P3 tape 6 made of, for example, glass fiber or varnish cloth, which contains a curing accelerator for the impregnated resin. As can be seen from the drawings, according to the present invention, the insulating tape 6a close to the conductor 1 has a large loss mesh, and after winding the insulating tape 6a a predetermined number of turns, the insulation tape 6a has a loss mesh smaller than the insulating tape 6a. The tape 6b is wound, and an insulating tape 6C of two small diameter mesh is further wound on top of the tape 6b. In this way, an insulating layer of a desired thickness is formed.

Next, the wire-wound conductor on which the insulating layer has been formed is placed in a resin impregnating device and subjected to vacuum pressure impregnation treatment. In this case, there are many gaps between the wound layers of the insulating tape 6 on the conductor 1 side, so the oil impregnates at a faster rate than the conventional insulating tape with the same cross mesh, and at the same time, the air inside is quickly removed. be done. Therefore, insulation tape 6
Even if the insulating layer contains a resin curing accelerator, the impregnation rate is fast, so the impregnated resin will not harden before the internal air is removed, and no voids will be formed in the insulating layer. Also, the impregnation process takes a shorter time.

This can also be applied to the peel-off mica insulation tape used for the stator winding of the high-voltage rotating machine mentioned above. In this case, mica is attached to one side of the glass fiber, so it is impregnated from the direction A through the layer. Although the ratio due to impregnation from direction B of the a layer is high.

By making the glass fiber cross meshes different in size, the larger the cross meshes, the more voids there will be on the surface along the layer, so the impregnation speed from the layer direction B will be faster, and air will be quickly removed from the inside. Therefore, no voids are created in the insulating layer.

Note that the present invention applies to high pressure l! ! Although the stator winding of a one-turn machine has been described, it can of course be applied to the winding of another hypocardial device.

〔Effect of the invention〕

According to the present invention, the following advantages can be obtained.

(1) There is no risk of creating voids in the insulation layer of the winding conductor;
Good insulation properties can be obtained and a long insulation life of the single-winding conductor can be guaranteed.

(2) Since the impregnation speed of the winding conductor with the resin is increased, the impregnation process is shortened.

[Brief explanation of drawings]

Fig. 1 is a schematic diagram of a stator winding of a rotating machine, Fig. 2 is an explanatory diagram showing an example of the conventional overlapping state of insulating tapes of winding conductors, and Fig. 3 is a diagram showing the size of the cross mesh based on the present invention. FIG. 3 is an explanatory diagram of an example of winding insulating tapes having different values. l Two winding conductors, two slot parts, 3: end part, 4
: 10 out part, 5: Insulating tape. 6: Insulating tape.

Claims (1)

[Claims] 1) An insulating tape containing a hardening accelerator for the impregnated resin is wound around the white wire conductor, the wire-wound conductor is impregnated with a thermosetting resin under vacuum pressure, and then the thermosetting resin is heated. A method for insulating a wire-wound conductor to be cured, characterized in that the size of the fiber mesh of the insulating tape containing a curing prolonging agent is made different on the side close to the wire-wound conductor and on the side away from the wire-wound conductor. Method of insulating winding conductors. 2. A method for insulating a wire-wound conductor according to claim 1, wherein the fiber mesh of the insulating tape is gradually made smaller as it moves away from the wire-wound conductor. 3) A method for insulating a wire-wound conductor according to claim 1 or 2, wherein the insulating tape containing a curing accelerator is a peelable mica insulating tape lined with glass fiber. . 4) The method according to any one of claims 1 to 3 (2) in which the insulating tape containing a curing accelerator is wound around the wound conductor after the mica tape assembly is wound. Features a winding conductor insulation method.