阅读说明：本技术 一种凸极绕线式发电机转子绕组的绝缘方法 (Insulation method for rotor winding of salient-pole wound generator ) 是由 郭季强 张燕 王逸文 于 2021-07-27 设计创作，主要内容包括：本发明公开了一种凸极绕线式发电机转子绕组的绝缘方法,包括以下步骤：在第一个磁极的绕线通道上均匀地涂刷一层绝缘胶；将绝缘纸压贴在涂好绝缘胶的第一个磁极的绕线通道上；将四张绝缘纸一一对应地贴放在两对绕组支撑上；在第一个磁极的绕线通道和两对绕组支撑上自内向外绕制第一层绕组；在第一层绕组的表面均匀地涂刷绝缘胶,再自外向内绕制第二层绕组至最外层绕组,第二层绕组的导线与第一层绕组的导线交错叠齐；每绕完一层绕组即涂刷一层绝缘胶；对转子绕组进行测量直流电阻、绝缘电阻以及耐电压试验；将转子放入烘箱进行绝缘胶的烘焙固化。本发明能使转子绕组之间的气隙充满绝缘胶,保证转子绕组在旋转时极高的粘结强度和绝缘的可靠性。(The invention discloses an insulation method of a rotor winding of a salient pole wound generator, which comprises the following steps: uniformly brushing a layer of insulating glue on a winding channel of the first magnetic pole; pressing and pasting the insulating paper on the winding channel of the first magnetic pole coated with the insulating glue; the four pieces of insulation paper are correspondingly attached to the two pairs of winding supports one by one; winding a first layer of windings from inside to outside on a winding channel of the first magnetic pole and the two pairs of winding supports; uniformly coating insulating glue on the surface of the first layer of winding, winding the second layer of winding from outside to inside to the outermost layer of winding, and overlapping the conducting wires of the second layer of winding and the conducting wires of the first layer of winding in a staggered manner; coating a layer of insulating glue after winding a layer of winding; carrying out direct current resistance, insulation resistance and voltage resistance test on the rotor winding; and (4) putting the rotor into an oven to bake and solidify the insulating glue. The invention can fill the air gap between the rotor windings with insulating glue, and ensure the extremely high bonding strength and insulation reliability of the rotor windings during rotation.)

1. A method of insulating a rotor winding of a salient pole wound generator, the method comprising the steps of:

step one, uniformly coating a layer of insulating glue on a winding channel of a first magnetic pole of a rotor core;

secondly, pressing and attaching insulating paper to a winding channel of the first magnetic pole coated with insulating glue, enabling two ends of the insulating paper to extend out of the end face of the driving side and the end face of the non-driving side of the rotor core to be equal in length, fixing two pairs of winding supports at two ends of the first magnetic pole in a one-to-one correspondence mode, and fixing a winding former on the rotor core and aligning to the first magnetic pole;

step three, a long insulating sleeve and a short insulating sleeve are sequentially sleeved from the head end of the lead, the short insulating sleeve and the long insulating sleeve are far away from the head end of the lead, then the head end of the lead is fixed on the non-driving side of the first magnetic pole, which is close to the rotor core, and simultaneously four pieces of insulating paper are correspondingly attached to the two pairs of winding supports one by one;

winding a first layer of winding from inside to outside on a winding channel of the first magnetic pole pressed with the insulating paper and two pairs of winding supports by using a winding machine, and moving the short insulating sleeve and the long insulating sleeve backwards all the time during winding;

step five, uniformly coating insulating glue on the surface of the first layer of winding to enable the insulating glue to fill gaps among the wires, then winding the second layer of winding from outside to inside to the outermost layer of winding, and enabling the wires of the second layer of winding to be staggered and overlapped with the wires of the first layer of winding; coating a layer of insulating glue after winding each layer of winding, and sequentially circulating until winding to the last but one turn of the outermost winding;

step six, when the penultimate turn of the outermost winding is wound, the reserved short insulating sleeve is placed at the non-driving end close to the rotor core, when the last turn of the outermost winding is wound, the reserved long insulating sleeve is also placed at the non-driving end close to the rotor core, one end of the long insulating sleeve, which faces the driving end of the rotor core, is flush with one end of the short insulating sleeve, which faces the driving end of the rotor core, the long insulating sleeve and the short insulating sleeve are tightly wrapped by a thin copper sheet and are firmly welded, then a layer of insulating glue is coated on the surface of the outermost winding, and finally the lead is cut off, and the tail end of the lead with a certain length is reserved;

step seven, removing the winding former on the first magnetic pole, repeating the steps one to six, and winding the winding of the second magnetic pole until the winding of the rest magnetic poles is completed;

step eight, performing end insulation binding on the winding end part of each magnetic pole;

step nine, installing a plurality of line pressing blocks at intervals along the length direction of the rotor core between the straight line sections of the windings of the adjacent magnetic poles, and filling an insulating paper between each line pressing block and the surface of the winding;

step ten, welding the head ends of the leads of the adjacent magnetic poles and the tail ends of the leads in series, finally leading out two lines as positive and negative leads, respectively welding a flexible cable to the positive and negative leads, half-overlapping all welding joints with glass ribbons, sleeving insulating sleeves, and uniformly coating insulating glue on all binding positions and joints;

step eleven, carrying out direct current resistance, insulation resistance and voltage resistance test on the rotor winding;

step twelve, putting the qualified rotor into an oven for baking and curing the insulating glue;

and thirteen, spraying epoxy paint on the surface of the cured rotor winding and then transferring to the next procedure.

2. The method of claim 1, wherein the insulation paste is an epoxy resin insulation paste having a viscosity of 70000 mpa-sec at 25 ℃ at room temperature.

3. The method of insulating a rotor winding of a salient pole wound generator according to claim 1, wherein said insulating paper has a heat resistant temperature of 180 ℃.

4. The method of insulating a rotor winding of a salient pole wound generator according to claim 1, wherein said long bushing, said short bushing and said bushing are all silicone bushings.

5. The method of claim 1, wherein the wire is an enameled round copper wire with a polyester or polyimide insulation film having a heat resistance of 180 ℃ or 220 ℃.

6. The method of insulating a rotor winding for a salient pole wound generator according to claim 1, wherein the step of applying the insulating paste is performed while maintaining the temperature of the insulating paste at 30 to 40 ℃.

7. The method of insulating a rotor winding of a salient pole wound generator according to claim 1, wherein the step four is performed by adjusting a pressure of a tension device of the winding machine to 0.5 Mpa.

8. The method of claim 1 wherein the step eleven withstand voltage test is conducted with a voltage of 1000 volts applied at twice the rated voltage for 1 minute.

9. The method of insulating a rotor winding for a salient pole wound generator according to claim 1, wherein the curing temperature is 150 to 160 ℃ and the baking time is 16 to 36 hours in the twelfth step.

Technical Field

The invention relates to an insulation method of a rotor winding of a salient pole wound generator.

Background

The existing synchronous generator mostly adopts a salient pole wound rotor as an excitation source, and the wound rotor enables the rotor to generate a magnetic field required by induced electromotive force by winding a copper conductor on each magnetic pole of the rotor under the condition of electrifying the copper conductor, so that the armature winding of the synchronous generator generates induced electromotive force and further outputs voltage to the outside. Based on the operating principle of a synchronous generator, an essential condition for generating an induced electromotive force is that the rotor of the synchronous generator rotates at a certain fixed rotational speed, and the rotational speed of the rotor depends on the number of poles of the generator, the more the number of poles, the lower the speed at which the rotor rotates, and the less the number of poles, the higher the speed at which the rotor rotates. With the development of science, the single-machine capacity requirement of the synchronous generator is higher and higher at present, so that the rotor of the synchronous generator is required to be larger. What salient-pole wound rotors are to overcome in operation is that under high speed rotation, the insulation of their windings and the windings themselves are not damaged by the large centrifugal forces.

The insulation curing method for the rotor winding commonly used at present adopts a vacuum dipping method. The vacuum paint dipping method is mainly characterized in that negative pressure is generated in a paint dipping tank through vacuumizing, epoxy resin insulating paint is dipped into the paint dipping tank where a rotor is located from a paint storage tank and permeates into an air gap of a rotor winding, the epoxy resin insulating paint is attached to the surface of the winding through the viscosity of the insulating paint, and the insulating paint on the surface of a coil is cured after the insulating paint is heated by an oven, so that a firm paint film is formed on the surface of the winding, and the effect of strengthening insulation is further achieved. In order to ensure good fluidity of the insulating paint, the method requires that the viscosity of the insulating paint is low, the low viscosity cannot ensure good adhesion of the insulating paint, and the paint dipping is generally repeated for more than two times to ensure the paint hanging amount of the insulating paint.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provide an insulation method of a rotor winding of a salient-pole wound generator, which can fill an air gap between rotor windings with insulation glue, improve the integrity and mechanical strength of the rotor windings, improve the insulation quality of the generator, ensure the extremely high bonding strength and insulation reliability of the rotor windings during rotation and prolong the service life of the generator.

The purpose of the invention is realized as follows: a method of insulating a rotor winding of a salient pole wound generator comprising the steps of:

step one, uniformly coating a layer of insulating glue on a winding channel of a first magnetic pole of a rotor core;

secondly, pressing and attaching insulating paper to a winding channel of the first magnetic pole coated with insulating glue, enabling two ends of the insulating paper to extend out of the end face of the driving side and the end face of the non-driving side of the rotor core to be equal in length, fixing two pairs of winding supports at two ends of the first magnetic pole in a one-to-one correspondence mode, and fixing a winding former on the rotor core and aligning to the first magnetic pole;

step three, a long insulating sleeve and a short insulating sleeve are sequentially sleeved from the head end of the lead, the short insulating sleeve and the long insulating sleeve are far away from the head end of the lead, then the head end of the lead is fixed on the non-driving side of the first magnetic pole, which is close to the rotor core, and simultaneously four pieces of insulating paper are correspondingly attached to the two pairs of winding supports one by one;

winding a first layer of winding from inside to outside on a winding channel of the first magnetic pole pressed with the insulating paper and two pairs of winding supports by using a winding machine, and moving the short insulating sleeve and the long insulating sleeve backwards all the time during winding;

step five, uniformly coating insulating glue on the surface of the first layer of winding to enable the insulating glue to fill gaps among the wires, then winding the second layer of winding from outside to inside to the outermost layer of winding, and enabling the wires of the second layer of winding to be staggered and overlapped with the wires of the first layer of winding; coating a layer of insulating glue after winding each layer of winding, and sequentially circulating until winding to the last but one turn of the outermost winding;

step six, when the penultimate turn of the outermost winding is wound, the reserved short insulating sleeve is placed at the non-driving end close to the rotor core, when the last turn of the outermost winding is wound, the reserved long insulating sleeve is also placed at the non-driving end close to the rotor core, one end of the long insulating sleeve, which faces the driving end of the rotor core, is flush with one end of the short insulating sleeve, which faces the driving end of the rotor core, the long insulating sleeve and the short insulating sleeve are tightly wrapped by a thin copper sheet and are firmly welded, then a layer of insulating glue is coated on the surface of the outermost winding, and finally the lead is cut off, and the tail end of the lead with a certain length is reserved;

step seven, removing the winding former on the first magnetic pole, repeating the steps one to six, and winding the winding of the second magnetic pole until the winding of the rest magnetic poles is completed;

step eight, performing end insulation binding on the winding end part of each magnetic pole;

step nine, installing a plurality of line pressing blocks at intervals along the length direction of the rotor core between the straight line sections of the windings of the adjacent magnetic poles, and filling an insulating paper between each line pressing block and the surface of the winding;

step ten, welding the head ends of the leads of the adjacent magnetic poles and the tail ends of the leads in series, finally leading out two lines as positive and negative leads, respectively welding a flexible cable to the positive and negative leads, half-overlapping all welding joints with glass ribbons, sleeving insulating sleeves, and uniformly coating insulating glue on all binding positions and joints;

step eleven, carrying out direct current resistance, insulation resistance and voltage resistance test on the rotor winding;

step twelve, putting the qualified rotor into an oven for baking and curing the insulating glue;

and thirteen, spraying epoxy paint on the surface of the cured rotor winding and then transferring to the next procedure.

The insulation method of the rotor winding of the salient pole wound generator is characterized in that the insulation glue is epoxy resin insulation glue with viscosity reaching 70000 mPas at the normal temperature of 25 ℃.

In the insulation method of the rotor winding of the salient pole wound generator, the heat-resistant temperature of the insulation paper is 180 ℃.

In the insulation method of the rotor winding of the salient pole wound generator, the long insulation sleeve, the short insulation sleeve and the insulation sleeve all adopt silica gel insulation sleeves.

In the insulation method of the rotor winding of the salient pole wound generator, the lead adopts the enameled round copper wire with the polyester imide or polyimide insulation film, the heat-resistant temperature of which is 180 ℃ or 220 ℃.

In the insulation method for the rotor winding of the salient pole wound generator, the temperature of the insulating glue is kept at 30-40 ℃ before the insulating glue is coated in the first step.

In the insulation method of the rotor winding of the salient pole wound generator, the pressure of the tension device of the winding machine is adjusted to 0.5Mpa when the step four is carried out.

In the insulation method of the rotor winding of the salient pole wound generator, when the withstand voltage test of the step eleven is carried out, 1000 volts is added for 1 minute at twice rated voltage.

The insulation method of the rotor winding of the salient pole wound generator comprises the step twelve, wherein the curing temperature is 150-160 ℃, and the baking time is 16-36 hours.

The insulation method of the rotor winding of the salient pole wound generator has the following characteristics:

1) the invention adopts the enameled round copper wire with the polyester imide or polyimide insulating film, the enameled round copper wire has good insulating property, the heat-resistant temperature is 180 ℃ or 220 ℃, the insulating paper with the polyester film sandwiched between two layers of aramid paper is adopted to be padded under the wire and isolated from the rotor core, the insulating paper can resist the temperature of 180 ℃, the insulating level between the winding and the rotor core is enhanced, and meanwhile, the insulating film of the wire is well protected; the epoxy resin insulating adhesive with the viscosity reaching 70000 mPa.s at the normal temperature of 25 ℃ is also adopted, and the insulating adhesive provides good insulating property and extremely high bonding strength for the rotor after being cured, so that the rotor winding on the magnetic pole can bear larger centrifugal force without loosening;

2) the insulation method of the invention coats the surface of the winding with the insulation glue in the winding process to ensure that each gap of the winding is filled with the insulation glue, and the insulation glue can not run off in the curing process due to the high viscosity of the insulation glue, thereby ensuring that the cured winding can be bonded into a whole, improving the insulation performance and the mechanical strength of the winding, and in addition, the anti-corrosion paint coated on the surface of the winding after curing can effectively isolate moisture from permeating into the winding, well protecting the insulation performance of the winding in the use process, and prolonging the service life of the generator.

Drawings

Fig. 1 is a state diagram when step five of the insulation method of the present invention is performed.

Detailed Description

The invention will be further explained with reference to the drawings.

The invention relates to an insulation method of a rotor winding of a salient pole wound generator, which adopts insulation paper, insulation glue, an insulation sleeve, a rotor winding machine with a tension device and an oven. Wherein the insulating paper is composite insulating paper with a polyester film sandwiched between two layers of aramid paper, and the heat-resistant temperature of the insulating paper is 180 ℃; the insulating adhesive is epoxy resin insulating adhesive which has no solvent, no diluent and no pungent smell and has viscosity of 70000 mPa.s at the normal temperature of 25 ℃; the insulating sleeve adopts a silica gel sleeve; the wire of the winding adopts an enameled round copper wire with a polyester imide or polyimide insulating film, and the heat-resistant temperature is 180 ℃ or 220 ℃.

The insulation method of the rotor winding of the salient pole wound generator comprises the following steps:

step one, uniformly brushing a layer of insulating glue on a winding channel of a first magnetic pole of a rotor core 33 by using a brush, and keeping the temperature of the insulating glue at 30-40 ℃ by using heat-insulating equipment before brushing;

secondly, pressing and attaching insulating paper to a winding channel of the first magnetic pole coated with insulating glue, enabling two ends of the insulating paper to extend out of the end face of the driving side and the end face of the non-driving side of the rotor core to be equal in length, fixing two pairs of winding supports 34 at two ends of the first magnetic pole in a one-to-one correspondence mode through pins, and fixing a winding former 32 on a rotor core 33 and aligning the winding former to the first magnetic pole;

step three, a long insulating sleeve with the length of 150mm and a short insulating sleeve with the length of 20mm are sequentially sleeved from the head end of the lead, the short insulating sleeve and the long insulating sleeve are far away from the head end of the lead, then the head end of the lead is fixed on the non-driving side of the first magnetic pole, which is close to the rotor core 33, and meanwhile, four pieces of insulating paper are correspondingly attached to the two pairs of winding supports 34 one by one; the long insulating sleeve and the short insulating sleeve are both silica gel sleeves;

winding a first layer of winding from inside to outside on a winding channel of a first magnetic pole pressed with the insulation paper and the two pairs of winding supports 34 by using a winding machine, wherein the first layer of winding enables wires to be arranged in a tangent mode through a wire arranging block of the winding die 32, and the pressure of a tension device of the winding machine 31 is adjusted to 0.5Mpa during winding; during winding, the short insulating sleeve and the long insulating sleeve are moved backwards all the time;

step five, uniformly brushing insulating glue on the surface of the first layer of winding by using a brush or a spatula to fill gaps among the wires with the insulating glue, then winding the second layer of winding from outside to inside to the outermost layer of winding, and staggering and overlapping the wires of the second layer of winding and the wires of the first layer of winding; after winding one layer of winding 30, brushing a layer of insulating glue by using a brush or a spatula 35 (see figure 1), and sequentially circulating until the last but one turn of the outermost layer of winding is wound;

step six, when the penultimate turn of the outermost winding is wound, placing the reserved short insulating sleeve at the non-driving end close to the rotor core, when the last turn of the outermost winding is wound, placing the reserved long insulating sleeve at the non-driving end close to the rotor core, enabling one end of the long insulating sleeve, which faces the driving end of the rotor core, to be flush with one end of the short insulating sleeve, which faces the driving end of the rotor core, tightly wrapping the long insulating sleeve and the short insulating sleeve by using a thin copper sheet with the thickness of 0.3 mm, firmly welding the thin copper sheet, then coating a layer of insulating glue on the surface of the outermost winding by using a brush or a spatula, finally cutting off the lead, and reserving the tail end of the lead with the length of 200 mm to finish the winding of the first magnetic pole;

step seven, removing the winding former on the first magnetic pole, repeating the steps one to six, and winding the winding of the second magnetic pole until the winding of the rest magnetic poles is completed;

step eight, performing end insulation binding on the winding end part of each magnetic pole by using a glass wire binding pipe, binding two magnetic poles without air ducts on the winding end part, and binding four magnetic poles with air ducts on the winding end part, wherein each magnetic pole is in two circles;

after insulating binding of the end parts, mounting a plurality of line pressing blocks at intervals along the length direction of the rotor core between the straight line sections of the windings of the adjacent magnetic poles, and plugging an insulating paper between each line pressing block and the surface of the winding to ensure the insulation between the line pressing blocks and the winding; the wire pressing block can compact the rotor winding to prevent the winding from deforming or loosening;

step ten, welding the head ends of the leads of the adjacent magnetic poles and the tail ends of the leads in series, finally leading out two lines as positive and negative leads, respectively welding a flexible cable to the positive and negative leads, half-overlapping all welding joints with glass ribbons, sleeving insulating sleeves, and uniformly coating insulating glue on all binding positions and joints;

step eleven, carrying out direct current resistance, insulation resistance and voltage resistance tests on the rotor winding, wherein in the voltage resistance tests, the rated voltage of 2 times is increased by 1000V for 1 minute;

step twelve, placing the rotor which is qualified in the test into an oven for baking and curing the insulating glue, wherein the curing temperature is 150-160 ℃, and the baking time is 16-36 hours;

and thirteen, spraying epoxy paint on the surface of the cured rotor winding and then transferring to the next procedure.

The invention relates to an insulation method of a rotor winding of a salient pole wound generator, which changes the traditional insulation curing method, adopts a pre-insulated round enameled copper conductor as the winding of a rotor, pads a pre-formed composite insulation paper sandwiched with a polyester film below the copper conductor to isolate the conductor from a rotor core, coats high-viscosity epoxy resin insulation glue on the surface of the winding in the process of winding the enameled copper conductor on a rotor magnetic pole, and finally cures the rotor winding through a hot oven to cure the epoxy resin insulation glue so as to achieve the insulation performance required by the rotor and the strength performance of the winding of the rotor in a high-speed rotation state.

The above embodiments are provided only for illustrating the present invention and not for limiting the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and therefore all equivalent technical solutions should also fall within the scope of the present invention, and should be defined by the claims.