CN112564364B

CN112564364B - Insulation structure of high-voltage motor

Info

Publication number: CN112564364B
Application number: CN202011510992.4A
Authority: CN
Inventors: 刘林; 张坤
Original assignee: Chongqing Electric Machine Federation Ltd
Current assignee: Chongqing Electric Machine Federation Ltd
Priority date: 2020-12-18
Filing date: 2020-12-18
Publication date: 2022-08-09
Anticipated expiration: 2040-12-18
Also published as: CN112564364A

Abstract

The invention discloses an insulation structure of a high-voltage motor in the field of high-voltage motor insulation, which comprises coil insulation, slot insulation and integral insulation, wherein the coil insulation comprises conductor insulation and end insulation, the slot insulation comprises in-slot insulation and notch insulation, and the conductor insulation is a round copper wire which is coated by a polyimide-F46 composite film and sintered into a whole and serves as a conductor. The invention can effectively solve the problems that the existing insulation technology can not meet the requirement of 10000V high-voltage motor conductor insulation, and dangerous conditions such as discharge exist in the use process.

Description

Insulation structure of high-voltage motor

Technical Field

The invention relates to the field of high-voltage motor insulation, in particular to an insulation structure of a high-voltage motor.

Background

The insulation system is an important component of the machine, and its performance and condition determine the safety and life of the machine in operation. The voltage of conventional high-voltage motor is 3000V, 6000V, 10000V etc. and its present conventional high-voltage insulation system can satisfy general high-voltage motor operation requirement, but to the high-voltage motor of special requirement (high frequency, high pressure, vacuum, special environment, electrical parameter etc.) adopt conventional high-voltage insulation system can appear the problem that can't overcome. The insulating requirement can not be met, phenomena such as corona and local breakdown discharge often occur, the local temperature in the coil can be increased due to the thermal effect generated by the corona, the oxide of ozone and helium and the like, the adhesive is deteriorated and carbonized, the strand is insulated and the mica is whitened, and then the strand is loose, short-circuited, insulated and aged. The breakdown discharge comprises conductor insulation breakdown discharge, notch discharge and the like, and the discharge can cause the problems of insulation breakdown, air ionization and the like, so that the whole insulation is seriously damaged, and the use safety of the high-voltage motor is seriously influenced.

Disclosure of Invention

The invention aims to provide an insulation structure of a high-voltage motor, which aims to solve the problems that the existing insulation technology cannot meet the conductor insulation requirement of a 10000V high-voltage motor and dangerous conditions such as discharge exist in the use process, and meets the use requirements of the motor with special requirements (high frequency, high voltage, vacuum, special environment, electrical parameters and the like).

In order to achieve the purpose, the basic technical scheme of the invention is as follows: the utility model provides an insulation system of high-voltage motor, includes coil insulation, slot insulation, interphase insulation and whole insulation, and the coil insulation includes conductor insulation and tip insulation, and the slot insulation includes ground insulation and notch insulation, and the conductor insulation is the outer polyimide-F46 composite film of cladding of round copper line and sinters into the whole, and polyimide-F46 composite film is one of coil interturn insulation and the ground insulation of winding.

The principle and the advantages of the scheme are as follows: in the insulating structure of 10000V class high voltage motor, polyimide-F46 composite film is firstly used, after high temperature sintering, it is bonded with the coated round copper wire to form an integral conductor and coil insulation, and its "polyimide-F46 composite film" is used as a part of turn-to-turn insulation of coil and ground insulation of winding. The insulation thickness of the round copper wire processed in the way reaches more than 0.63mm, the voltage resistance is 8700V, the breakdown voltage reaches 15000V, the turn-to-turn voltage and the impact turn-to-turn voltage of a high-voltage motor can be effectively borne, the conductor insulation failure in the use process is avoided, and the stability and the reliability of the coil insulation are effectively ensured.

Further, the interphase insulation is five layers of more and less mica foils arranged between adjacent interphase pads. Preferably, the low-resin-powder mica foil is used at the interphase of the coil end, so that interphase insulation can be effectively performed after subsequent vacuum pressure paint dipping treatment, an insulating layer is formed to be compact and reliable, and the phenomenon that interphase breakdown generates short-circuit current can be effectively avoided.

Furthermore, the end part of the coil is insulated by six layers of multi-layer mica tapes which are half-overlapped and wrapped at the end part of the coil. Preferably, the coil end is reinforced with insulation protection again in a half-lap-wrapping mode, and after the vacuum pressure dip coating treatment, the coil end is ensured to be effectively insulated and have enough mechanical strength outside the iron core.

Furthermore, the end part insulation also comprises a strengthening processing structure, and the strengthening processing structure is formed by coating a plurality of glue mica layers on the end part of the coil and brushing high-voltage insulation epoxy resin for natural curing. Preferably, the coil end is insulated integrally again on the basis of interphase insulation and lap insulation, and epoxy resin is added, so that the integral field intensity of the coil end is improved, the corona starting voltage of a coil winding is increased, the generation of corona is controlled effectively, and the stability and reliability of coil insulation are ensured.

Further, an anti-corona structure is arranged in the groove, and the anti-corona structure comprises a low-resistance paint layer, a low-resistance foil layer, a film mica tape, a glass mica tape and a film mica tape which are sequentially arranged from the iron core to the coil in the groove. As the preferable mode of effectively ensuring the corona prevention effect in the stator core slot through the low-resistance paint and the low-resistance foil, the mode of combining the film mica tape and the glass mica tape is favorable for effectively locking the insulating paint after the subsequent insulating paint is dipped, and the insulating effect of the coil winding in the core slot is enhanced.

Furthermore, the glass mica tape is provided with six layers, and the thin film mica tape and the glass mica tape are high-pressure low-glue mica tapes. Preferably, the absorption locking effect on the insulating varnish is better, and the insulation protection effect on the coil winding in the iron core slot is better.

Further, the ground insulation comprises eight layers of dry mica foil wrapped on the coil. Preferably, after the subsequent vacuum pressure dip coating treatment, the ground insulation can be effectively carried out, and the formed insulation layer is compact and reliable.

Furthermore, the notch insulation comprises a glass cloth pressing plate, and notches with the same size as the stator slots are formed in the glass cloth pressing plate. Adopt insulating glass cloth clamp plate like this as the clamp plate of stator core as preferring for stator core both ends insulating effect is better, and the position that breaks down easily is regarded as to the stator core notch, adopts glass cloth clamp plate to increase the creepage distance of iron core groove outlet, effectively improves insulating properties, avoids the main insulation of main insulation damage and outlet to puncture and discharge.

Furthermore, the notch insulation also comprises a paint hanging pad positioned below the slot wedge, and the paint hanging pad is made of heat-resistant porous adsorptive materials. As the optimal paint hanging pad with the heat-resistant porous adsorption property, the paint hanging amount can be effectively increased in the subsequent integral paint dipping and baking process, the gap between the round copper wire and the notch of the iron core is sealed, the risk of air ionization is reduced, and meanwhile, the notch discharge is effectively prevented.

Further, the paint coating pad is one of felt, mineral wool pad or glass wool pad. The materials are preferably adopted as the paint hanging pad, so that the paint hanging amount is more after paint dipping, the high temperature resistance is realized in the using process, and the insulation protection on the notch and the sealing effect on the gap are better.

Further, the integral insulation comprises insulating paint which is coated and filled among all insulation of the stator integral body, and the winding iron core integral body is subjected to vacuum pressure paint dipping, so that the insulating paint is filled among the high-voltage stator winding and all insulation materials and is solidified with the stator iron core into a whole. The whole vacuum pressure dip coating process treatment is preferably carried out after the insulation of each part is finished, so that the insulating paint is filled in each tiny space of the insulating system under the action of pressure, an insulating whole is formed through baking and curing, the insulating effect is remarkably improved, and the phenomena of corona, breakdown discharge and the like in the using process are effectively avoided.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment of the present invention;

fig. 2 is a schematic structural diagram of the trench isolation according to the embodiment of the present invention.

Detailed Description

The following is further detailed by way of specific embodiments:

reference numerals in the drawings of the specification include: stator core 1, glass cloth clamp plate 2, tip insulation 3, inslot insulation 4, paint coating pad 5, slot wedge 6, electromagnetic wire 7.

The embodiment is basically as shown in the attached figure 1: the utility model provides an insulation system of high voltage motor, includes coil insulation, slot insulation and whole insulation, and the coil insulation includes conductor insulation and tip insulation 3, and the slot insulation includes that inslot is insulating 4 and notch are insulating, and conductor insulation is for using polyimide-F46 compound film cladding and sintering round copper line as whole as electric conductor magnet wire 7. The end insulation 3 comprises interphase insulation and pack insulation, and the interphase insulation is five layers of multi-glue mica foil arranged between adjacent interphase insulation in a cushion manner. The lap-wrapped insulation comprises six layers of multi-layer mica tapes which are half-lapped at the end part of the coil. The end insulation 3 further comprises a multi-glue mica layer coated on the outer sides of the phase insulation and the lap insulation, and epoxy resin is coated between layers of the multi-glue mica layer. Referring to fig. 2, the in-slot insulator 4 includes a low-resistance paint layer, a low-resistance foil layer, a film mica tape, a glass mica tape, and a film mica tape, which are sequentially disposed from the core to the coil. The glass mica tape is provided with six layers, and the film mica tape and the glass mica tape are high-pressure low-glue mica tapes. The notch insulation comprises a glass cloth pressing plate 2, and notches with the same size as the stator slots are formed in the glass cloth pressing plate 2. The notch insulation also comprises a paint hanging pad 5 positioned below the slot wedge 6, and the paint hanging pad 5 is made of heat-resistant porous adsorptive materials. The integral insulation comprises insulating paint which is coated and filled between the insulation of the whole stator. The specific implementation process is as follows: the high-voltage electromagnetic wire 7 of the high-voltage motor stator coil is formed by coating a polyimide-F46 composite film on a round copper wire and bonding the round copper wire into an integral conductor after high-temperature sintering, wherein the polyimide-F46 composite film is formed by coating perfluorinated ethylene propylene resin on one side or two sides of the polyimide film and sintering the perfluorinated ethylene propylene resin at high temperature, the polyimide-F46 composite film integrates the characteristics of the polyimide film and fluoroplastic, is high-temperature resistant and low-temperature resistant, is not easy to burn, has flame retardance reaching UL-94/V-0 level, has excellent electrical performance, dimensional stability and chemical corrosion resistance, and can be rapidly melted and bonded and molded in the using process. The insulation thickness of the electromagnetic wire 7 after being processed in the way reaches 0.63mm, the withstand voltage is 8700V, the breakdown voltage is 15000V, and the inter-turn voltage and the impulse inter-turn voltage of the high-voltage motor can be effectively borne. The main insulating material in the stator core 1 slot adopts high-voltage little-glue mica foil 5442T with the thickness of 0.13mm, the withstand voltage is not less than 1500V, the insulating structure of a multi-layer wrapping electromagnetic wire 7 is adopted, and the stator coil is embedded in the stator slot in a random winding mode. The stator slot is firstly sprayed with anticorona low-resistance paint, then a layer of low-resistance foil is placed to enhance the anticorona effect, a layer of thin film mica tape 5442DC is placed, six layers of glass mica tapes 5442T are placed, and a layer of thin film mica tape 5442DC is placed, so that the insulating paint can be effectively locked and the insulating effect can be enhanced in the integral vacuum pressure paint dipping process. The iron core groove tip adopts the glass cloth board as the clamp plate, compares conventional metal clamp plate, can effectively increase the creepage distance of outlet, avoids the main insulation damage and the main insulation breakdown of outlet. The felt that establishes the one deck 2mm thick is filled up as hanging lacquer pad 5 under the slot wedge 6 of stator notch, adsorbs insulating paint when vacuum pressure dip coating technology, increases the volume of hanging lacquer, effectively seals the clearance between round copper line and the iron core notch, reduces air ionization's risk, also prevents simultaneously that the notch from discharging. At the end part of the stator coil, which is positioned at the outer side of the iron core slot, five layers of multi-glue powder mica foil pads are firstly used for forming interphase insulation at intervals, then six layers of 0.13X 25 multi-glue powder mica tapes are half-overlapped and wrapped at the end part of the coil, after being bound, the multi-glue mica tapes and the stator are soaked and baked with high-pressure insulating resin for curing, finally the end part is coated with the multi-glue mica layers, 9811 epoxy resin is coated between layers, the field intensity of the end part of the coil is improved, and the corona starting voltage of a coil winding is improved. And finally, placing the whole motor stator in a sealed tank, exhausting air, injecting insulating paint to immerse the stator, pressurizing to enable the insulating paint to fill all tiny spaces of the insulating system under the action of pressure, and baking to form an insulating whole, so that the whole insulating effect is obviously improved. Through the high voltage motor insulation system who obtains handling like this, 1 groove of stator core, notch, stator coil tip all obtain the effective insulation protection of strengthening, wholly handle through vacuum pressure dip coating, and insulating varnish is effectively filled to each position, and whole each position insulating properties is reliable and stable, can effectively satisfy 10000V high voltage motor's user demand, effectively avoids the emergence of phenomenon such as corona, breakdown discharge, guarantees high voltage motor's long-time stable safe operation. The sample machine manufactured by the insulating structure and the insulating process of the 10000V-level high-voltage motor meets and exceeds the corona technical index of the high-voltage motor in JB/T843-wall 2008 of the national standard through tests. The pressure test of the prototype machine meets the technical index requirements of the factory pressure test of the high-voltage motor. The leakage current of the prototype is superior to the level of the insulation structure of the conventional high-voltage motor.

Winding-to-ground voltage resistance test:

serial number	Applying a voltage	U-V to ground (leakage current A)	U-W to ground (leakage current A)
				1	7000V	0.043	0.042
2	8000V	0.048	0.047
				3	9000V	0.056	0.056
4	10000V	0.063	0.062
				5	11000V	0.072	0.074
6	12000V	0.084	0.083
				7	13000V	0.092	0.092

And (3) winding interphase voltage resistance test:

the foregoing is merely an example of the present invention and common general knowledge in the art of specific structures and/or features of the invention has not been set forth herein in any way. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.

Claims

1. An insulation system of high-voltage motor which characterized in that: the stator coil is a loose coil and comprises coil insulation, slot insulation, phase insulation and integral insulation, wherein the coil insulation comprises conductor insulation and end insulation, the end insulation is a six-layer multi-glue powder mica tape which is half-lap wrapped at the end of the coil, the phase insulation is a multilayer little-glue powder mica foil which is arranged between adjacent phases for padding, the slot insulation comprises ground insulation and notch insulation, the ground insulation comprises eight layers of little-glue powder mica foil which are wrapped on the coil, a linear part of the loose coil is wrapped in an iron core slot in a layered mode, the notch insulation comprises a glass cloth pressing plate and a paint hanging pad which is positioned below a slot wedge, a notch with the same size as the stator slot is formed in the glass cloth pressing plate, the paint hanging pad is made of heat-resistant porous adsorptive material, the conductor insulation is a polyimide-F46 composite film which is wrapped outside a round copper wire and is sintered into a whole, the polyimide-F46 composite film is one of turn insulation of the coil and ground insulation of a winding, the high-voltage motor stator coil is a loose coil, and a corona-proof structure is arranged in the slot and comprises a low-resistance paint layer, a low-resistance foil layer, a film mica tape, a glass mica tape and a film mica tape which are sequentially arranged from the iron core to the coil in the slot; the integral insulation is that the winding iron core is integrally subjected to vacuum pressure paint dipping, so that insulating paint is filled between the high-voltage stator winding and each insulating material, and the high-voltage stator winding and each insulating material are solidified into a whole with the stator iron core.

2. The insulation structure of a high-voltage electric machine according to claim 1, characterized in that: the end part insulation structure further comprises a strengthening processing structure, and the strengthening processing structure is formed by coating a plurality of glue mica layers on the end part of the coil and painting a high-voltage insulation epoxy resin layer.

3. The insulation structure of a high-voltage electric machine according to claim 2, characterized in that: the paint hanging pad is one of felt, mineral cotton pad or glass cotton pad.