JPS59159521A - Manufacture of molded winding - Google Patents

Abstract

PURPOSE:To enhance the mechanical strength of a sheathed insulating layer bond between layers by simultaneously heating resin of semicured state of prepreg insulator and resin impregnated with fiber reinforced material, and curing the both resins in the integrated state. CONSTITUTION:A winding covered by a sheathed insulating layer 8 is conveyed into a heating furnace together with a bobbin 1, resin of semicured state of a prepreg insulating 4 and resin impregnated with fiber reinforced material are simultaneously heated and cured. At this time the resin of the semicured state in the prepreg insulator is fused by the heat to impregnate with an insulating base 5 which is not impregnated with resin, mutually fused with the resin imprengated with fiber reinforce material so that the both resins are integrally cured. In this manner, interlayer insulating layers 61-6n-1 and a sheathed insulating layer 8 are integrated to complete a molded winding.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing molded windings used in molded transformers and the like.

Conventional technology As a manufacturing method for molded windings, an insulating base material is impregnated with a thermosetting resin liquid to form a semi-cured prepreg insulating material to form an insulating layer between the eyebrows, and an exterior insulating layer is formed by resin casting. There is a way to do it.

In this manufacturing method, a winding conductor is first wound a predetermined number of turns around the outer periphery of an inner insulating layer formed on the outer peripheral surface of a winding frame.
A pre-preg insulating material is wound around the outer peripheral surface of the winding layer to form an interlayer insulating layer. Next, the winding conductor is wound again around the outer periphery of this interlayer insulating layer to form a second winding layer, and the formation of the interlayer insulating layer and the winding layer are then repeated alternately to form a winding with a predetermined number of turns. Wind the wire. Next, this winding wire is removed from the winding frame, and after preheating at a predetermined heating temperature until the entire winding reaches a uniform temperature, this winding wire is placed in a casting mold, and the winding wire is placed in a casting mold. Vacuum inject thermosetting resin liquid into the mold. After injection of the resin liquid is completed, the winding wire is heated together with the casting mold to harden the resin liquid. After the resin has hardened, the casting mold is removed to complete the molded winding covered with an exterior insulating layer of resin.

However, in the above manufacturing method, the semi-hardened resin of the Gripreg insulation material that forms the glabella insulation layer is completely hardened during preheating of the winding, so the edges of each interlayer insulation layer At the interface between the part and the exterior insulation layer, the resin of the fully cured prepreg insulation material and the resin of the exterior insulation layer, which was injected and cured by heating later, cannot be integrated harmoniously, resulting in insufficient mechanical strength. I couldn't get it. Furthermore, if a molded winding manufactured by the above conventional method is incorporated into a transformer, cracks may occur at the joint between the end of the interlayer insulation layer and the exterior insulation layer due to temperature changes in the molded winding. In this case, the insulation strength decreases (1), and creeping discharge may occur at the end portion of the interlayer insulating layer (the end surface portion where the interlayer voltage is highest).

OBJECTS OF THE INVENTION An object of the present invention is to integrate the resin at the end of the interlayer insulating layer and the resin of the exterior insulating layer so that the bonding between the two is complete;
An object of the present invention is to provide a method for manufacturing a molded winding wire that improves mechanical strength and eliminates the possibility of creeping discharge occurring at the end of an interlayer insulating layer.

Structure of the Invention The manufacturing method of the present invention includes a step of winding a wire-wound conductor around a winding frame to form a single winding layer, and a step of impregnating an insulating base material with a thermosetting resin f to form a green-cured state. The steps of forming an interlayer insulation layer by winding a laminate of prepreg insulating material and an insulating base material not impregnated with resin around the outer periphery of the front pie winding layer are repeated alternately to form the above l interlayer insulation between the layers. A winding is formed of a plurality of winding layers with intervening layers. Next, the outer surface of the winding is covered with a fiber reinforcing material impregnated with a thermosetting resin to form an exterior insulation layer. After Z), the semi-cured resin of the prepreg insulation and the resin impregnated into the fiber reinforcing material are simultaneously heated and cured.

In this way, when the green-cured resin of the prepreg insulation material and the resin impregnated into the fiber reinforcing material are simultaneously heated and cured, the bond between the end of the interlayer insulation layer and the exterior insulation 1@
Then, both resins melt into each other and harden in a state where they become a harmonious body. Therefore, it is possible to increase the mechanical strength of the joint between the end of the I-interlayer insulating layer and the exterior insulating layer, thereby eliminating the possibility of creepage insulation collapse occurring at the end of the loose interlayer insulating layer. Can be done.

Example An embodiment of the present invention will be described below with reference to the drawings.

FIG.
This is an example of a molded winding.When manufacturing all molded windings, the first step is to use fiber-reinforced plastic (
A cylindrical winding frame 1 made of (FRP) is prepared 2, and a winding conductor 2 is wound a predetermined number of turns around the outer peripheral surface of this winding frame.
The fi-th winding layer 31 is formed. Next, an insulating base material such as a woven fabric or non-woven fabric made from a silky insulating material, an insulating material, an insulating paper, etc. is impregnated with the thermosetting resin 11) liquid, and then heated to a specified temperature. Prepreg insulation material 4 impregnated with 2/ξ resin to a semi-hardened state by processing (this insulation material is separate)
Make it in two steps. An interlayer insulating layer 61 is formed by winding a laminate of a resin and an insulating base material 5 not impregnated with resin around the outer periphery of the winding layer 31. When forming a laminate of a prepreg insulating material and an insulating base material whose open side is not impregnated, the insulation Sogetsu material constituting the prepreg insulating material and the insulating base material which is not impregnated with resin are used. The material may be the same or may be different as appropriate.

Alternatively, a plurality of insulating base materials not impregnated with prepreg insulating material and resin may be laminated in an appropriate direct order (for example, alternately). When an interlayer insulating layer is formed by appropriately combining a prepreg insulating material and an insulating base material not impregnated with resin and laminating them 5 times, the interlayer insulating strength can be increased. Among the materials used for the prepreg insulating material, including the insulating T4 base material and the insulating base material not impregnated with resin, examples of the fiber-bound insulating material 1 include glass cloth and glass nonwoven fabric.

It is possible to use polyester nonwoven fabric, aromatic boryamide nonwoven fabric (trade name: Nomex nonwoven fabric), etc. Further, insulating films and insulating paper (, -(, Mylar film, Kaptonfil l-, Nomex paper (all trade names), kraft paper, etc. can be used.

After forming the interlayer insulating layer 61, the winding conductor 2 is again wound a predetermined number of turns on the outer peripheral surface thereof to form a second winding layer 32, and a glabella insulating layer is formed on the outer periphery of this winding layer 3t. do.

Thereafter, the steps of forming a winding layer and forming an interlayer insulating layer are repeated alternately in the same way to form winding layers 31 to 3n (n is 2).
(above integer) and interlayer insulation lit6l to 6n-1, a winding 7 having a predetermined number of turns is formed.

Next, a resin-impregnated fiber reinforcement material made by impregnating a fiber reinforcement material such as glass roving or glass tape with a thermosetting resin liquid is applied to the outer peripheral surface of the winding frame that protrudes outward from both ends of the winding wire 7 in the axial direction. The liquid is wound in an uncured state, and this winding operation is continued until both end faces in the axial direction of the winding 7 are completely covered, and the end exterior insulation 1f181.
Form 81. Thereafter, a resin-impregnated fiber reinforcing material similar to that described above is wound to cover the outer circumferential surface of the winding 7 and the outer circumferential surface of the end outer insulating layers s, , s i to form an outer circumferential outer insulating layer 82, The winding 7 is completely covered with an exterior insulating layer 8 consisting of an end exterior insulating layer 81.81 and an outer exterior insulating layer 82.

Next, the winding covered with the exterior insulating layer 8 as described above is carried into a heating furnace together with the winding frame 1, and the prepreg insulating material 4
The semi-cured resin and the resin impregnated into the fiber reinforcing material are simultaneously heated and cured.

At this time, the semi-hardened resin in the prepreg insulation material is melted by heating and penetrates into the insulating base material 5 which is not impregnated with resin, and also melts into the resin impregnated into the fiber reinforcing material. , both resins are harmoniously integrated and cured. As a result, a molded winding in which the interlayer insulating layers 61 to 6n-1 and the exterior insulating layer 8 are integrated is completed.

In the above method, the first winding layer is wound directly around the outer periphery of the winding frame 1 so that the winding frame 1 constitutes a part of the exterior of the molded winding. First, a laminate of a prepreg insulating material 4 and an insulating base material 5 not impregnated with resin is wound on the winding frame 1 to form an inner insulating layer 9, and then a first layer is applied to the outer periphery of the inner insulating layer 9. The winding layer 31 may be wound, and after the outer insulating layer 8 is formed, the winding frame 1 is removed and then placed in a heating furnace to harden the resin.

Further, in this case, the inner peripheral side insulating layer 9 is replaced with the prepreg insulating material 4
It can also be formed by chisel. Furthermore, an inner insulating layer is formed by winding a resin-impregnated fiber reinforcing material around the entire length of the winding frame 1, and after the resin in the inner insulating layer is semi-hardened, the winding is completed. Effects of the Invention As described above, according to the manufacturing method of the present invention, the semi-cured resin of the prepreg insulation material and the resin impregnated into the fiber reinforcement material are simultaneously heated. Since both resins are cured in an integrated state, the mechanical strength of the joint between the end of the interlayer insulating layer and the exterior insulating layer can be increased. Therefore, when the molded winding is incorporated into a transformer and used, even if the temperature of the molded winding changes due to energization, cracks will not occur at the joint between the end of the interlayer insulation layer and the exterior insulation layer. , it is possible to increase the insulation strength, eliminate the possibility of creeping dielectric breakdown occurring at the end of the interlayer insulating layer, and obtain a highly reliable molded winding.

[Brief explanation of the drawing]

FIG. 1 is a half longitudinal sectional view showing an example of a molded winding wire manufactured according to an embodiment of the present invention, and FIG. 2 is a winding frame of a molded winding wire manufactured according to another embodiment of the present invention. FIG. 3 is a half longitudinal cross-sectional view showing the state before removal. DESCRIPTION OF SYMBOLS 1... Winding frame, 2... Winding conductor, 3□~3n... Winding layer. 4... Prepreg insulating phase, 5... Insulating base material, 61
~6 Toto... Interlayer insulation layer, 7... Winding wire, 8... Exterior insulation layer.

Claims (1)

[Claims] A process of winding a wire conductor around the circumference of a winding frame to form a single winding layer, and a process of impregnating an insulating base material with a thermosetting resin to a semi-cured prepreg insulating material and impregnating the resin. A step of forming an interlayer insulating layer by winding a laminate of an insulating base material around the outer peripheral surface of the winding layer is alternately repeated to form a plurality of layers with the interlayer insulating layer interposed between the layers. A winding consisting of a winding layer is formed, the outer surface of the winding is then covered with a fiber reinforcement material impregnated with a thermosetting resin to form an exterior insulation layer, and then the semi-cured state of the prepreg insulation material is covered. A method for manufacturing a molded winding wire, characterized in that a resin and a resin impregnated into the fiber reinforcing material are simultaneously heated and cured.