CN1117383C - High-voltage winding with resin insulation for transformer and its manufacture method - Google Patents

Abstract

The present invention belongs to the technical field of transformers, and particular relates to a transformer high-voltage coil and a manufacturing method thereof; the transformer high-voltage coil is formed by winding resin impregnated glass filament bundles into coils which are packaged and insulated in a mould. The present invention is characterized in that the coils is formed by connecting more than eight sections of cylindrical graded coils with more than seven layers in series, and no insulating layer exists among layers of the graded coils. The manufacturing method is characterized in that insulating layers on inner and outer walls are formed by winding resin glass fiber grids, and the coil is wound by dividing the coil into two large sections from a middle tap to both ends; graded coils in each large section are continuously wound without broken ends among the graded coils, and steps of winding graded coils and winding, packaging and insulating resin glass fibers are separated. The invention has the advantages of compact structure, convenient manufacture, etc.

Description

A kind of manufacture method of resin insulating transformer high-tension coil

The present invention relates to a kind of glass filament bundle of crossing with resin impregnation and be wound in that coil is sealed insulation and in the manufacture method of the transformer high-voltage coil of die for molding, it is applicable to makes 35KV and following 16000KVA and following resin insulating dry type transformer.

At present, both at home and abroad the plexiglas silk of the making high-tension coil that twines transformer all adopts and whenever then twines one deck plexiglas silk around one deck electromagnetic wire and do insulation, coil is by the structure coiling of one section multi-layer cylinder formula or two sections multi-layer cylinder formulas, under rotary state, be cured the technology manufacturing of moulding again, there is following defective in it: 1. whole process is all carried out in air, without vacuum degassing, even the resin system material is through vacuum treatment, in winding process, always there is bubble to bring in the layer insulation and appearance unavoidably, be difficult to control the partial discharge quantity of product, cause this key index of partial discharge to exceed the minimum value standard of national regulation easily, the ambassador's electrical strength of crossing that office puts reduces, insulation is aging easily, shorten useful life, if remedy with the measure that increases the insulation size, obviously increased small product size again, increased material cost, this is very uneconomic.2. in order to twine every layer interlayer insulating film, whenever after an intact layer line, must cut off the end of every layer of every section last circle line, behind intact insulating barrier, weld again and continue coiling, and intersection is carried out so repeatedly, this just causes every layer at least 2 pads that weld are again all arranged, behind sandwich wound, whole winding just has several plumb joints, causes loose contact easily, and resistance increases, even the wedge angle burr occurs and poke a layer turn insulation, cause the accident of short circuit, poor reliability is when the county expends a large amount of Welder.3. coil inwall main insulating layer adopts fiber board to do insulating cylinder, and product is made moist, and reduces insulation level.4. in winding process, do not rotate if take place to pause, particularly when welding every layer of electromagnetic wire of being cut off and drawing shunting tap, the time of pausing is longer, following immediately of resin on the coil, both caused waste, and made operator's two hands stick resin, operating difficulties again, and this phenomenon all takes place from start to finish, and labour health is very poor.5. the coil appearance is because twined one deck glass fiber, and simultaneously, wire turn is out-of-flatness also, also just can't accomplish the smooth of outer surface, always has rugged ripple, directly influences the specious of product.6. when every layer of glass fiber need intersect coiling, higher, complicated to equipment requirements, invest also big.

The objective of the invention is to provide a kind of glass filament bundle to twine the back and in the manufacture method of the transformer high-voltage coil of die for molding with tape tree fat, it can overcome above-mentioned defective, need not every layer every section and cut off electromagnetic wire, coiling and wrapping wire are carried out in two stages, avoid winding the line and to intersect the plumb joint that carries out many for wrapping wire, operation inconvenience, the phenomenon of labour health environment difference, and thoroughly slough the air bubble of bringing coil into, simultaneously, make the coil appearance have smooth smooth surface again, make product both have high mechanical strength, have very high electrical strength again, the insulation size is dwindled, volume reduces, cost reduces, appearance looks elegant, the humidity resistance excellence, useful life characteristics such as director, integrate winding of plexiglas silk and vacuum around annotating both strong points, become the advanced product of the new generation of resin insulating transformer.

The present invention is achieved in that

The first step is coiling.The coiling mould of different sizes is contained on the coil winding machine main shaft on demand, this winding former also is last shaping mould, on mould, make coil inwall insulating barrier earlier, can be directly twining certain thickness with the glass fiber of tape tree fat also can be with prefabricated profiled plexiglas screen grid plate, this waffle slab is the flexible waffle slab that epoxy resin-impregnated has been solidified under vacuum, on this inwall insulating barrier around copper (or aluminium) electromagnetic wire, the loop construction pattern is the multistage drum type brake, the 10KV level is more than 8 segments reach, the 35KV level is more than 20 segments, the tapping voltage tap is at the middle part, turn to two big sections from the coil middle part to two ends, do not cut off between each segment in every big section, coiling continuously is when the electromagnetic wire turn insulation can bear the electrical strength test of voltage between layers, need not layer insulation, behind intact line, must put in order and dry each section, make it to meet insulating requirements.When privileged sites need be strengthened layer insulation, can be at the interlayer pad with nonwoven fabrics, or in coiling, twine the semi-drying glass fiber adhesive tape of epoxy resin-impregnated.

Second step was the glass fiber of strip winding resin.Pad to guarantee the insulation of section space transition line, uses the glass fiber of tape tree fat two-layer in the winding of whole winding outer surface with certain filling insulant then earlier between per two segments, puts into the prefabricated profiled plexiglas screen grid of one deck plate simultaneously.Do not put regulation when requiring when coil has office, so far then can send in the curing oven, be cured under rotation status, the demoulding promptly obtains the plexiglas silk and twines a low office unwrapping wire circle.

The 3rd step was that vacuum pressure is handled.Put when having relatively high expectations when the office to coil, the coil to the intact glass fiber of above-mentioned winding refills the external mold coaming plate, vacuumizes processing in vacuum tank, with the whole bubbles inside and outside the venting coil.Remove vacuum again, add air pressure and handle, resin can fully be soaked into, further improve the compactness of structure.

The 4th step was the cured process.The coil of external mold is housed, pours into a mould the curing of product and program routinely into.After the demoulding, promptly make the unwrapping wire circle little innings.

The present invention takes following technological means to make high-tension coil both have high mechanical strength, has very high electrical strength again, also reduced the volume of product, reduced cost, improved outward appearance: 1. with the glass fiber of tape tree fat put down around with intersect coiling, also add prefabricated profiled glass fiber grid plate, guaranteed high mechanical strength; 2. the gas credit is eliminated in vacuum treatment, reduces office and puts, and has improved electrical strength greatly; 3. pressure treatment promptly improves the compactness of structure, makes the smooth in appearance light again; 4. the inwall insulating barrier has replaced fiber board with plexiglas silk or waffle slab, and disposable making prevents that product from making moist, and improves machinery and electrical strength, reduces the size that insulate.5. the continuous coiling of many segments does not have broken end, no layer insulation or do not cut off wire turn and add insulation, raising product reliability and reduced volume; 6. coiling is not to intersect repeatedly to carry out with wrapping wire, but carries out in two stages, has improved labour health condition widely.

Below in conjunction with drawings and Examples the present invention is further described:

Fig. 1 is a high-tension coil structural representation of the present invention.

Fig. 2 is that the B of Fig. 1 is to view.

Make inwall insulating barrier 1 earlier, shunting tap 2 is at the middle part, divide two big sections coiling sectional coil 3 continuously, fill insulant 4 and be placed between every segment, outer wall insulating barrier 5 and overhang insulation 6 solidify under the rotation situation around the pitch of the laps that finishes the plexiglas silk, be low office unwrapping wire circle after the demoulding, if the dress mould solidifies after vacuum and pressure treatment, the unwrapping wire circle is then made in the demoulding little innings.

The hop count of segmented line Fig. 3 should be determined according to the height of coil voltage grade and the electrical strength of electromagnetic wire.When coiling 3 mutually during the high-tension coil of 10 kilovolts of D connections, the voltage of every phase coil is 10000 volts, be divided into after 8 sections, every section voltage is 1250 volts, divide 9 layers of coiling again, then every layer of voltage average out to is 138.9 volts, and the voltage between layers between the adjacent two layers is 277.8 volts, this voltage also has reliable electrical strength for the electromagnetic wire of modification enamel insulation without other layer insulation.Equally, when coiling 3 mutually during the high-tension coil of 35 kilovolts of D connections, by segmentation and layering, voltage between layers is controlled at, and the voltage between layers level of above-mentioned 10KV line coil is with the electromagnetic wire coiling of modification enamel insulation, without other layer insulation, also has reliable electrical strength.When privileged sites need be strengthened layer insulation, during the coiling sectional coil,, make between the resin penetrating layer, or in coiling, twine the semi-drying glass fiber adhesive tape of epoxy resin-impregnated at interlayer pad nonwoven fabrics.

According to method of the present invention, can accomplish to make the Resin Wound mould molding identical with the product design data of vacuum pouring type, most materials and universal component reduce material stock, save the occupation of capital, shorten the production cycle.

Claims (1)

1, a kind of manufacture method of resin insulating transformer high-tension coil, it is characterized in that inwall insulating barrier (1) and outer wall insulating barrier (5) are rolled by the glass fiber of plexiglas screen grid plate and tape tree fat forms, coil begins to divide two big sections coilings to two ends from the middle part tap, between the sectional coil (3) in every big section coil is the continuous coiling of not breaking end, coiling sectional coil (3) with twine the plexiglas silk and seal insulation and separate and carry out, coil after the winding is heated and cured into low office and puts product under rotary state, be heating and curing after vacuum pressure is handled if be contained in the mould, then make little office and put product.