JP3607448B2 - Rotating electric machine and insulation method of rotating electric machine winding - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a rotating electrical machine such as a squirrel-cage multiphase induction motor used for automobiles and the like, and a method for insulating a rotating electrical machine winding.
[0002]
[Prior art]
Some automobiles are called electric braking devices and use, for example, a rotating electric machine such as a cage-type multiphase induction motor. This electric braking device maintains a high braking force by consuming electric energy generated from a rotating electric machine during braking of an automobile by a resistor.
[0003]
And the rotating electrical machine used for this electric braking device is a so-called turbulent winding system in which enameled wire is wound many times in its winding to obtain the highest possible magnetic flux in a given narrow space The ones are considered optimal. In addition, such windings are designed to prevent the windings from being deformed or broken due to fatigue due to vibration during driving or electromagnetic vibration during rotation, or from moisture or rainwater contained in the outside air. It is necessary to protect the enameled wire, and for this reason, an insulation system in which a resin such as epoxy is impregnated and cured is known (Japanese Patent Application No. 2-92033, Japanese Patent Application No. 3-286605).
[0004]
[Problems to be solved by the invention]
However, according to the normal impregnation / curing insulation method applied to the windings of such rotating electrical machines, the resin impregnated in the windings flows out of the windings due to a decrease in gravity and viscosity during curing. In other words, unnecessary gaps may be formed in the iron core or windings inside the rotating electrical machine. In addition, the resin flow-out causes the enamel film to be easily affected by the external environment because the film thickness of the insulating layer formed on the enamel film of the enamel wire becomes thin, and the insulation deterioration caused by moisture and rainwater is reduced. In addition, there is a problem that the heat dissipation property is deteriorated, the temperature of the winding is increased, and the life of insulation is shortened due to thermal deterioration.
An object of the present invention is to provide a rotating electrical machine that is excellent in heat dissipation, moisture resistance, and water resistance, and that is particularly suitable as a rotating electrical machine for automobiles, and a method for insulating a rotating electrical machine winding.
[0005]
[Means for Solving the Problems]
The invention corresponding to claim 1 preliminarily heats the rotating electrical machine winding and drops an epoxy resin composition comprising an epoxy resin, an acid anhydride and a microencapsulated latent curing accelerator on the preheated rotating electrical machine winding. The epoxy resin composition is cured by the heat of the impregnated and preheated rotating electrical machine winding .
[0006]
The invention corresponding to claim 2 is the method for insulating a rotating electrical machine winding according to claim 1 , wherein the content of the microencapsulated latent curing accelerator in the epoxy resin composition is changed between the epoxy resin and the acid anhydride. It is 0.1-5 phr with respect to the sum total.
[0007]
The invention corresponding to claim 3 is the method of insulating a rotating electrical machine winding according to claim 2 , wherein the epoxy resin composition is added with a surface conditioner, and the amount of the surface conditioner is adjusted with the epoxy resin and the acid anhydride. 0.1 to 1 phr is included with respect to the total product.
[0008]
According to a fourth aspect of the present invention, in the method for insulating a rotating electrical machine winding according to the first aspect of the invention, the dripping impregnation of the epoxy resin composition is performed while heating the rotating electrical machine winding.
The invention corresponding to claim 5 uses the far-infrared heater for heating the epoxy rotating electrical machine winding in the method for insulating a rotating electrical machine winding of the invention corresponding to claim 4.
[0010]
The invention corresponding to claim 6 is the insulating method for a rotating electrical machine winding according to claim 1, wherein the dripping impregnation of the epoxy resin composition into the rotating electrical machine winding is performed while rotating the rotating electrical machine winding. .
[0011]
As a result, according to the invention corresponding to claim 1 , since the microencapsulated latent curing accelerator is added in advance to the resin composed of the epoxy resin and the acid anhydride, the capsule from the time when the film of the microcapsule is dissolved by heating. Because the hardening accelerator acts on the epoxy and acid anhydride and the oxidation reaction proceeds rapidly, the resin does not flow out, and the voids in the iron core and windings inside the rotating electrical machine are blocked. Thus, the resin can be filled.
[0012]
According to the invention corresponding to claim 2, a sufficient curing accelerating effect can be obtained, and a cured resin can form a satisfactory molecular structure and sufficient characteristics can be obtained.
According to the invention corresponding to claim 3, a sufficient wettability improvement effect can be obtained, and sufficient characteristics can be obtained by appropriate curing of the resin.
[0013]
According to the invention corresponding to claim 4, the dropped resin is warmed by contact with the heated rotating electrical machine winding, the viscosity decreases, and easily penetrates into the winding inside the iron core, In addition, the penetrated resin can be cured smoothly.
[0014]
According to the invention corresponding to claim 5 , since it is possible to warm from the inside of the resin by far-infrared rays, the resin can be efficiently cured by heating with less dropping due to the low viscosity of the resin.
[0016]
According to the invention corresponding to claim 6, by rotating and rotating the rotary electric machine winding, the resin impregnation and curing is performed so that the resin that falls due to gravity when left standing is rotated by 360 °. By rotating the direction of gravity acting on the resin by reversing the rotation, the fall can be prevented, and the space inside the winding inside the iron core and the surface of the winding outside the iron core can be densely filled with resin. excellent winding insulation is obtained.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 is a diagram for explaining a method for insulating a rotating electrical machine winding according to a first embodiment of the present invention. In the figure, reference numeral 1 denotes a rotating electrical machine. The rotating electrical machine 1 has an iron core 2 and a rotating electrical machine winding 3 wound around the iron core 2.
[0019]
The rotating electrical machine winding 3 is insulated by the method described below. First, the rotating electrical machine winding 3 is preheated to 130 ° C. in an oven or the like, and while dropping the resin 5 through a plurality of plastic tubes 4 from above the preheated rotating electrical machine winding 3, Impregnation into the rotating electrical machine winding 3. In addition, if the iron core 2 is tilted when the resin 5 is dropped, the flow of the resin 5 into the iron core 2 can be further facilitated with the help of gravity.
[0020]
Resin 5 is composed of an epoxy resin composition containing an epoxy resin and an acid anhydride and further containing a microencapsulated latent curing accelerator, and has a thickness of about 0.01 to 0.1 μm by heating. The film of the microcapsule composed of molecules is dissolved, and a curing accelerator having an average particle size of about several μm in the capsule acts on the epoxy and the acid anhydride so that the curing reaction proceeds rapidly.
[0021]
The epoxy resin constituting the resin 5 includes bisphenol A form, bisphenol F form, novolac form, cycloaliphatic form, glycidyl ester form, glycidylamine form, heterocyclic form and polyfunctional epoxy resin. Examples of the product include aliphatic acid anhydrides, alicyclic acid anhydrides, halogen acid anhydrides, and the like.
[0022]
Further, the content of the microencapsulated latent curing accelerator in the resin 5 is 0.1 to 5 phr (per hundredresin) with respect to the total of the epoxy resin and the acid anhydride. Furthermore, such microencapsulated latent curing accelerator microcapsule films are chemically inactive at low temperatures, such as blocked isocyanate masked by reacting isocyanate groups with phenol, alcohol, caprolactam, etc., but heated. Then, the urethane bond is cleaved and the coating is broken, and the curing accelerator that reacts with the resin is used. Examples of the curing accelerator include 2-methylimidazole, 2-ethyl-4methylimidazole, An imidazole modified product such as 2-phenylimidazole or a blend of dicyandiamide and an imidazole modified product is used.
[0023]
Typical examples of commercially available microencapsulated latent curing accelerators include Asahi Kasei Kogyo Co., Ltd. trade names Novacure HX-3742, HX-3741 and the like.
[0024]
Thus, in the first embodiment, as the resin 5, Epicoat 828 (trade name of Shell) 75 parts by weight, DEN431 (trade name of Dow Chemical) 25 parts by weight, QH200 (trade name of Nippon Zeon) 70 weights Epoxy resin composition comprising HX-3742 (trade name of Asahi Kasei Kogyo Co., Ltd.) 0.1 to 5 phr as a microencapsulated latent curing accelerator and 0.1 to 1 phr of Disparon 1970 (trade name of Enomoto Kasei Co., Ltd.) as a surface conditioner Is used.
[0025]
Such a resin 5 is dropped through the tube 4 and impregnated in the rotating electrical machine winding 3, but in this process, the temperature within the microcapsule is below the temperature at which the microcapsules of the microencapsulated latent curing accelerator melt. Since the curing accelerator cannot be brought into contact with the epoxy resin and the acid anhydride, the curing proceeds slowly, and when the microcapsules melt, the reaction rapidly proceeds. That is, even if the resin 5 is dropped through the tube 4 and contacts the preheated rotating electrical machine winding 3, the resin 5 has a heat capacity, so the temperature of the resin 5 does not rise immediately, and the resin 5 is first warmed. As a result, the viscosity is lowered and the microcapsule melts and gels and hardens when the resin sufficiently penetrates into the iron core 2, whereby the gap of the rotating electrical machine winding 3 including the inside of the iron core 2. Is gelled and cured in a state of being filled with the resin 5.
[0026]
In this case, by adding a surface conditioner to the epoxy resin composition, the wettability of the resin 5 with respect to the enamel film, the insulator such as the slot insulator and the winding fixing thread is improved, and the resin 5 is sufficiently adhered, At the same time, it also serves as an antifoaming agent that prevents foaming during curing. Examples of the surface conditioner include modaflow (trade name of Monsanto) which is an acrylic polyphosphate ester, acrylic disparons 1970, 230, L-1984-50, L-1985-50 (trade name of Enomoto Kasei), silicone System TSA720 (trade name of Toshiba Silicone Co., Ltd.) is used.
[0027]
The microcapsule content was set to 0.1 to 5 phr with respect to the total of the epoxy resin and the acid anhydride. If the amount of microcapsule was less than 0.1 phr, a sufficient curing accelerating effect could not be obtained. If the amount is too high, a rapid reaction occurs, and a satisfactory molecular structure is not formed, so that sufficient characteristics cannot be obtained.
[0028]
In addition, the surface conditioner is added to improve the wettability of the resin with respect to an insulator such as an enamel film, a slot insulator, and a wire for fixing a winding so that the resin is sufficiently adhered. And, the amount of the surface adjusting agent is 0.1 to 1 phr with respect to the total of the epoxy resin and the acid anhydride because the effect of improving the wettability is sufficient when the amount of the surface adjusting agent is less than 0.1 phr. This is because the resin cannot be obtained, and if it exceeds 1 phr, adequate curing of the resin does not occur and sufficient characteristics cannot be obtained.
[0029]
(Second Embodiment)
FIG. 2 is a diagram for explaining a method of insulating a rotating electrical machine winding according to a second embodiment of the present invention, and the same parts as those in FIG.
[0030]
In this case, while rotating the periphery of the rotating electrical machine winding 3 wound around the iron core 2 of the rotating electrical machine 1 with a plurality of far infrared heaters 6, the rotating electrical machine winding is performed in the same manner as described in the first embodiment. The resin 5 is dropped and impregnated from above the wire 3 through a plurality of plastic tubes 4. Here, the reason why the resin 5 is dropped and impregnated while heating the rotating electrical machine winding 3 using the far-infrared heater 6 is that the far-infrared heater 6 can warm the resin 5 from the inside, thereby The resin 5 is efficiently heated. That is, when the rotating electrical machine winding 3 is heated by the far-infrared heater 6 and the resin 5 is dropped and impregnated, the dropped resin 5 is warmed by contact with the heated rotating electrical machine winding 3, and the viscosity is reduced. It is possible to easily penetrate into the rotating electrical machine winding 3 inside the iron core 2 and to smoothly cure the penetrated resin 5.
[0031]
In this way, by heating the rotating electrical machine winding 3 outside the iron core 2 that has a small heat capacity and is easy to cool, heat is also conducted inside the iron core 2, and the rotating electrical machine winding 3 inside the iron core 2 can also be heated. As a result, the resin 5 dripped onto the rotating electrical machine winding 3 outside the iron core 2 is sufficiently penetrated into the gap of the rotating electrical machine winding 3 inside the iron core 2 through this rotating electrical machine winding 3, and in this state the gel Can be cured. Further, since the resin 5 is dropped while heating the outside of the iron core 2, the resin dripped onto the rotating electrical machine winding 3 outside the iron core 2 can be completely cured, and a thick coating film can be obtained.
[0032]
When the rotary electric machine winding 3 preheated in the oven is taken out of the oven and then heated with the far infrared heater 6 while being dripped and impregnated with the resin 5, the desired temperature is shortened in a shorter time than the heating of the far infrared heater 6 alone. The far-infrared heater 6 can be used efficiently. In the second embodiment, an example of heating by the far-infrared heater 6 has been shown. However, as a heating method, other heaters such as an infrared lamp and an electric heater, hot air, energization, and a heating method using these in combination are used. It may be used.
(Third embodiment)
FIG. 3 is a diagram for explaining a method of insulating a rotating electrical machine winding according to a third embodiment of the present invention. The same reference numerals are given to the same portions as those in FIG.
[0033]
In this case, the jig 7 is attached to the iron core 2 around which the rotating electrical machine winding 3 is wound. This jig 7 rotates the entire rotating electrical machine 1 formed by winding the rotating electrical machine winding 3 around the iron core 2 around the central axis 201 of the iron core 2, and rotates the rotating electrical machine winding 3 together with the iron core 2. However, the resin 5 is impregnated and cured.
[0034]
In this way, by rotating the rotating electrical machine winding 3 and reversing the direction of the gravity acting on the resin 5, it is possible to prevent the resin 5 that may fall due to gravity from falling. That is, by impregnating and curing the resin 5 while rotating the rotating electrical machine winding 3, the resin 5 that falls due to gravity when left standing is rotated by 360 ° rotation of the rotating electrical machine winding 3. It is possible to prevent the fall by reversing the direction of gravity acting on the. As a result, the space inside the rotating electrical machine winding 3 inside the iron core 2 and the surface of the rotating electrical machine winding 3 outside the iron core 2 can be densely filled with the resin 5, and winding insulation with excellent insulation characteristics can be obtained. it can.
[0035]
Further, when the rotary electric machine winding 3 is rotated and at the same time the resin 5 is dropped and impregnated while heating the rotary electric machine winding 3 outside the iron core 2 with the far infrared heater 6, the effect of the second embodiment is further added, That is, the space in the rotary electric machine winding 3 inside the iron core 2 and the surface of the rotary electric machine winding 3 outside the iron core 2 can be densely filled with the resin 5, and winding insulation having excellent insulation characteristics can be obtained.
(Fourth embodiment)
FIG. 4 shows a schematic configuration of the fourth embodiment of the present invention. This fourth embodiment shows an example in which a rotating electrical machine that employs the method for insulating a rotating electrical machine winding according to the first to third embodiments is actually used as an automotive rotating electrical machine. Here, 1 shows an electric braking and auxiliary acceleration device for an automobile that is directly connected to a main shaft of an internal combustion engine in order to perform electric braking and auxiliary acceleration of the automobile with a rotating electrical machine.
[0036]
In this case, the internal combustion engine 10 of the automobile is directly connected to the rotor portion of the rotating electrical machine 1 composed of, for example, a cage multiphase induction machine. This rotating electrical machine 1 is applied with the insulating method for the rotating electrical machine winding described in the first embodiment, and the surfaces inside and outside the core can be sufficiently filled with resin, The heat dissipation is excellent and the current density can be increased.
[0037]
In addition, a controller 11 and a resistor 12 are connected to the rotating electrical machine 1, and a secondary battery circuit 13 is connected to the controller 11.
In such an electric braking and auxiliary acceleration device, excessive electric energy at the time of braking of the automobile can be dissipated by the resistor 12 to maintain a high braking force, and also as an auxiliary driving means at a low cost. It is possible to obtain a practical form that can be operated and that effectively generates a large brake torque over a wide range of rotational speed and for a long time.
[0038]
By the way, as a winding of the rotating electrical machine 1 used in such an electric braking and auxiliary acceleration device, in order to obtain a magnetic flux having a density as much as possible in a given narrow space, a so-called winding of an enamel wire is performed many times. The turbulent winding method is optimal. The windings of this rotating electrical machine are not exposed to the outside air so that the windings are not deformed, the insulation is broken, or the wires are not disconnected due to fatigue due to vibration during running or electromagnetic vibration during rotation. In order to protect the enameled wire from moisture and rainwater contained therein, it is necessary to impregnate a resin ring such as epoxy and cure and fix it. In particular, since it is mounted in a narrow space on the axle of an automobile, it is necessary to increase the current density in order to increase the output, and at the same time, it is necessary to have insulation reliability against rainwater.
[0039]
Thus, with regard to such a rotating electrical machine 1, the rotating electrical machine winding that has been impregnated and cured by a conventional method using a resin having the same composition as described in the first embodiment is described in A, the first embodiment. A rotating electrical machine winding in which resin is dropped and impregnated and cured by an insulating method is designated as B, and the rotating machine 1 using these rotating electrical machine windings has the same current from 100 ° C. when a heat cycle test is performed between 100 ° C. and 200 ° C. When investigating the relationship between temperature and time when energized and stopped at 200 ° C., the result shown in FIG. 5 was obtained, and the conventional method A has a lower thermal conductivity than B of the present invention. It turns out that it gets hot quickly and is hard to cool down. On the other hand, according to the insulation method of the present invention, since the insulation film can be made thick, it was confirmed that the insulation performance is not easily lowered even if rainwater or the like enters the rotary electric machine 1.
[0040]
【The invention's effect】
As described above, according to the present invention, it is possible to obtain a rotating electrical machine and a method for insulating a rotating electrical machine coil that are excellent in heat dissipation, moisture resistance, and water resistance, and are particularly suitable as a rotating electrical machine for automobiles.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing a method for insulating a rotating electrical machine winding according to a first embodiment of the present invention.
FIG. 2 is an explanatory view showing a method of insulating a rotating electrical machine winding according to a second embodiment of the present invention.
FIG. 3 is an explanatory diagram showing a method for insulating a rotating electrical machine winding according to a third embodiment of the present invention.
FIG. 4 is a diagram showing a schematic configuration of an example in which a rotating electrical machine to which the method for insulating a rotating electrical machine winding according to the present invention is applied is used in an electric braking and auxiliary acceleration device for an automobile.
FIG. 5 is a comparative diagram showing a temperature change in insulation according to the present invention and a conventional method when a rotating electrical machine used in the fourth embodiment of the present invention is subjected to a heat cycle test.
[Explanation of symbols]
1 ... rotating electric machine,
2 ... Iron core,
3 ... rotating electrical machine winding,
4 ... Tube,
5 ... resin,
6 ... Far infrared heater,
7 ... Jig,
10 ... an internal combustion engine,
11 ... Control device,
12 ... resistor,
13 ... Secondary battery circuit.

Claims (6)

Pre-heated rotating electrical machine winding by pre-heating the rotating electrical machine winding, dripping and impregnating the pre-heated rotating electrical machine winding with an epoxy resin composition comprising an epoxy resin, an acid anhydride and a microencapsulated latent curing accelerator A method of insulating a rotating electrical machine winding, wherein the epoxy resin composition is cured by the heat of 2. The rotating electrical machine winding according to claim 1, wherein the content of the microencapsulated latent curing accelerator in the epoxy resin composition is 0.1 to 5 phr with respect to the total of the epoxy resin and the acid anhydride. Insulation method. The rotating electrical machine according to claim 2, wherein the epoxy resin composition is added with a surface conditioner, and the amount of the surface conditioner is included in an amount of 0.1 to 1 phr with respect to the sum of the epoxy resin and the acid anhydride. Winding insulation method. 2. The method for insulating a rotating electrical machine winding according to claim 1, wherein the dripping impregnation of the epoxy resin composition is performed while heating the rotating electrical machine winding. 5. The insulation method for a rotating electrical machine winding according to claim 4, wherein a far-infrared heater is used for heating the rotating electrical machine winding. The method for insulating a rotating electrical machine winding according to claim 1, wherein the dripping impregnation of the epoxy resin composition into the rotating electrical machine winding is performed while rotating the rotating electrical machine winding.

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