Preparation method of thin insulating layer motor winding

Abstract

The invention discloses a preparation method of a thin insulating layer motor winding, which comprises the following steps: S1, a CP20-375 insulating material is coated on the circumferential surface of a copper conductor, the double surfaces of slot insulating paper and the inner surface of an iron core slot, the thickness of the coating layer on the circumferential surface of the copper conductor is 10-50 microns, and the thickness of the coating layer on the double surfaces of the slot insulating paper and the inner surface of the iron core slot is 3-5 microns; s2, drying the copper conductor coated with the CP20-375 insulating material, the slot insulation paper and the iron core; s3, bending the copper conductor with the insulating layer made of the CP20-375 material according to the overall dimension designed by the stator winding; s4, forming slot insulation paper according to the size of the stator iron core slot, and sequentially inserting the slot insulation paper into the iron core slot; s5, inserting the plurality of bare copper conductors bent in the step S3 into an iron core groove to form a stator winding, and welding the end part of the stator winding and a leading-out wire; and S6, heating, pressurizing and curing the stator core obtained in the step S5. According to the invention, the characteristics of thin insulating layer, no paint dripping and high NVH (Noise Vibration and Harshness) performance of the motor winding of the new energy automobile can be met.

Description

Technical Field

[0001] The patent of this invention relates to the field of motor technology, specifically to the winding insulation structure of the drive motor of new energy vehicles. Background Art

[0002] With the rapid development of new energy vehicle technology, high power density and high efficiency are required for drive motors. The thickness of the enameled wire insulation layer usually used in motor windings is 75μm-150μm, which occupies more space in the stator slots, reduces the proportion of copper conductors in the slots, affects the power density and efficiency of the motor, and cannot meet people's demand for higher power density motors. In addition, in order to fix the winding and slot insulation paper in the core to improve the NVH performance of the motor during operation, it is necessary to perform long-term paint dripping and curing after the wire is embedded, which seriously affects production efficiency. Summary of the invention

[0003] The present invention provides a method for preparing a motor winding with a thin insulating layer, which can meet the characteristics of a motor winding of a new energy vehicle having a thin insulating layer, no paint dripping, and high NVH performance.

[0004] The technical solutions to the above problems are as follows: A method for preparing a thin insulating layer motor winding comprises the following steps: S1, using CP20-375 insulation material to coat the circumference of the copper conductor, both sides of the slot insulation paper and the inner surface of the core slot, wherein the thickness of the coating layer on the circumference of the copper conductor is 10-50 μm, and the thickness of the coating layer on both sides of the slot insulation paper and the inner surface of the core slot is 3-5 μm; S2, drying the copper conductor, slot insulation paper and iron core coated with CP20-375 insulation material to form an insulation layer of CP20-375 material on the surface of the copper conductor, slot insulation paper and iron core slot; S3, bending the copper conductor with the insulation layer of CP20-375 material according to the designed external dimensions of the stator winding; S4, forming slot insulation paper according to the size of the stator core slots, and inserting the slot insulation paper into the core slots in sequence; S5, inserting the bare copper conductors bent in S3 into the core slots to form a stator winding, and welding the stator winding ends and lead wires; S6, heating and pressurizing the stator core obtained in S5 to solidify, so that the insulation layers between the core slots and the slot insulation paper, and between the slot insulation paper and the winding undergo bonding reactions, thereby forming an insulation layer with high insulation performance and high bonding strength.

[0005] Furthermore, the drying in S2 is to bake the copper conductor with CP20-375 insulation material, slot insulation paper and iron core in a circulating oven, and the temperature is set at 200℃-240℃; the baking time of the copper conductor with CP20-375 insulation material is 60s, and the baking time of the double-sided coating of the slot insulation paper and the inner surface coating of the iron core slot is 30s.

[0006] Furthermore, the heating temperature of S6 is 260℃-280℃, and the pressure is 2-3N / mm 2 , duration is 60s.

[0007] The present invention uses CP20-375 material to coat the insulating layer on the circumference of the bare copper conductor of the motor winding, on both sides of the slot insulation paper, and in the core slot, and obtains a soft, stable and active coating in state B after drying and curing. Secondly, the winding is bent according to the designed winding outer dimensions, and the slots and embedded wires are completed. Finally, the CP20-375 insulating material in state B is heat and pressure cured to cause the insulating layer between the core slot and the slot insulation paper, and between the slot insulation paper and the winding to undergo a bonding reaction, forming an insulating layer in state C with high insulation performance and high bonding strength. The drive motor winding prepared by the present invention can effectively reduce the thickness of the insulating layer, improve the slot full rate, and achieve the purpose of improving the power density and efficiency of the motor; at the same time, it reduces the paint dripping process and improves production efficiency.

[0008] The advantages of the present invention are as follows: 1. Reduce the thickness of the insulation layer of the stator winding of the new energy drive motor and increase the slot fill rate to achieve the purpose of improving the power density and efficiency of the motor.

[0009] 2. Eliminate the paint dripping process in the production of motor stators to improve production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 A flow chart of a method for preparing a thin insulating layer motor winding according to the present invention; Figure 2 It is a copper conductor with a thermosetting resin insulation layer; Assembly diagram of the stator core and windings made of enameled rectangular wire; Symbols in the drawings: copper conductor 1, thermosetting resin insulation layer 2. DETAILED DESCRIPTION

[0011] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0012] like Figure 1 to Figure 2 As shown, a method for preparing a thin insulating layer motor winding of the present invention comprises the following steps: S1, CP20-375 insulation material is used to coat the circumferential surface of the copper conductor 1, the double sides of the slot insulation paper and the inner surface of the core slot, wherein the thickness of the circumferential surface coating layer of the copper conductor 1 is 10-50 μm, and the thickness of the coating layer on both sides of the slot insulation paper and the inner surface of the core slot is 3-5 μm.

[0013] In this embodiment, a layer of CP20-375 insulating material is applied to the circumference of the 3.2×2.5mm copper flat wire, both sides of the slot insulation paper, and the inner surface of the core slot by a roller coating process, wherein the thickness of the coating layer on the circumference of the copper conductor is 50μm, and the thickness of the coating layer on both sides of the slot insulation paper and the inner surface of the core slot is 4μm; the CP20-375 material is an insulating material produced by WILLE TECHCORP. The CP20-375 insulating material has three states: A, B, and C. The A state is a liquid with viscosity. In S1, the liquid in the A state is applied to the surface of the bonded part.

[0014] S2, drying the copper conductor, slot insulation paper and iron core coated with CP20-375 insulation material, forming an insulation layer of CP20-375 material on the surface of the copper conductor, slot insulation paper and iron core slot; the drying in S2 is to bake the copper conductor, slot insulation paper and iron core with CP20-375 insulation material in a circulating oven, and the temperature is set at 200℃-240℃; the baking time of the copper conductor with CP20-375 insulation material is 60s, and the baking time of the double-sided coating of the slot insulation paper and the inner surface coating of the iron core slot is 30s.

[0015] The CP20-375 insulating material in S1 can be dried to obtain the B state, which is a soft, stable and active coating. The coating is still reactive, that is, the coating can be bonded after the motor stator is embedded. The coating in the B state is corrosion-resistant and storage-stable.

[0016] S3, bending the copper conductor with the CP20-375 insulation layer according to the designed external dimensions of the stator winding.

[0017] S4, forming slot insulation paper according to the size of the stator core slots, and inserting the slot insulation paper into the core slots in sequence.

[0018] S5, inserting the several bare copper conductors bent in S3 into the core slots to form a stator winding, and welding the stator winding ends and lead wires.

[0019] S6, heat and pressurize the stator core obtained in S5 to solidify it, so that the insulation layer between the core slots and the slot insulation paper, and between the slot insulation paper and the winding will react to form an insulation layer with high insulation performance and high bonding strength. The heating temperature of S6 is 260℃-280℃, and the pressure is 2-3N / mm 2, duration is 60s.

[0020] In S6, heat and pressure curing act on the coating in state B to obtain a stable, highly chained thermosetting resin insulation layer 2 in state C. The thermosetting resin insulation layer in state C has the properties of high viscosity and strong adhesion.

[0021] The parameters of the motor stator prepared by the above method were measured, and the test results were: the power frequency withstand voltage was greater than 2850V, the insulation resistance was greater than 20MΩ, and the PDIV was greater than 1335V, which met the requirements for the use of new energy motors. For slots of the same size, the 50μm thick CP20-375 enameled wire insulation layer is thinner than the 75μm thick PI enameled wire insulation layer, has a higher slot fill rate, and a higher power density. In addition, the present invention has been subjected to a rolling peel test in accordance with the DIN 1464 standard, and the bonding strength is greater than 80000N / mm. Therefore, the present invention has the characteristics of bonding strength.

[0022] The above embodiments are part of the embodiments of the present invention. The embodiments described below with reference to the accompanying drawings are exemplary and intended to be used to explain the present invention, but cannot be simply understood as limiting the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

Claims

1. A method for preparing a thin insulating layer motor winding, It is characterized in that The following steps are involved: S1, CP20-375 insulation material is used to coat the circumference of the copper conductor, both sides of the slot insulation paper and the inner surface of the core slot; the thickness of the coating layer on the circumference of the copper conductor is 10-50μm, and the thickness of the coating layer on both sides of the slot insulation paper and the inner surface of the core slot is 3-5μm; S2, drying the copper conductor, slot insulation paper and iron core coated with CP20-375 insulation material to form an insulation layer of CP20-375 material on the surface of the copper conductor, slot insulation paper and iron core slot; S3, bending the copper conductor with the insulation layer of CP20-375 material according to the designed external dimensions of the stator winding; S4, forming slot insulation paper according to the size of the stator core slots, and inserting the slot insulation paper into the core slots in sequence; S5, inserting the bare copper conductors bent in S3 into the core slots to form a stator winding, and welding the stator winding ends and lead wires; S6, heating and pressurizing the stator core obtained in S5 to solidify, so that the insulation layers between the core slots and the slot insulation paper, and between the slot insulation paper and the winding undergo bonding reactions, thereby forming an insulation layer with high insulation performance and high bonding strength.

2. A method for preparing a thin insulating layer motor winding according to claim 1, It is characterized in that The drying in S2 is to bake the copper conductor with CP20-375 insulation material, slot insulation paper and iron core in a circulation oven, and the temperature is set at 200℃-240℃; the baking time of the copper conductor with CP20-375 insulation material is 60s, and the baking time of the double-sided coating of the slot insulation paper and the inner surface coating of the iron core slot is 30s.

3. A method for preparing a thin insulating layer motor winding according to claim 1, It is characterized in that The heating temperature of S6 is 260℃-280℃, and the pressure is 2-3N / mm 2 , duration is 60s.

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