Low-eddy-current-loss oblate mixed wire winding configuration structure

Abstract

The invention discloses a low-eddy-current-loss oblate mixed wire winding configuration structure which is characterized in that a round wire winding, a flat wire winding and a heat dissipation pipeline are configured in a stator tooth groove, the round wire winding is wound on one side of a groove opening of the stator tooth groove, and the heat dissipation pipeline is arranged in the middle of one side of the groove bottom of the stator tooth groove; the flat wire winding is wound on one side of the groove bottom of the stator tooth groove and located on the two sides of the heat dissipation pipeline, namely, a groove opening high-frequency leakage magnetic field area adopts a thin-wire-diameter round enameled wire to reduce winding eddy current loss, and a groove bottom area adopts a flat wire with a large cross section area to increase the groove fullness rate of the winding. Triangular areas among the flat wires are used for inserting heat dissipation pipelines so as to directly cool the stator and the winding thereof; therefore, by means of the low-eddy-current-loss oblate mixed wire winding configuration structure, the winding eddy-current loss can be reduced, meanwhile, the slot fullness rate of the winding is increased, and the torque output capacity of the motor is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of motors, and in particular relates to a low eddy current loss oblate hybrid wire winding configuration structure. Background Art

[0002] High-speed motors generally have higher power density and working efficiency than low-speed motors, and are therefore widely used in industrial scenarios such as engine fuel pumps, electromechanical actuators (EMAs), and air compression pumps. However, since the speed of high-speed motors is mostly above 15,000 rpm, the frequency of change of the motor air gap magnetic field is relatively large. This high-frequency magnetic field also causes the leakage magnetic field at the stator slot to change at a relatively high frequency. Therefore, eddy current losses are inevitably generated in the stator windings. In order to solve this problem, the stator windings 100 of high-speed motors often use fine-diameter enameled wires to divide the eddy currents and reduce the AC losses of the windings, such as Figure 1 In addition, there is also a solution in which the winding is not placed at the slot to avoid the high-frequency alternating magnetic field of the slot.

[0003] However, the method of using thinner round wires to cut off the eddy current will result in a lower slot fill rate of the winding, because the paint thickness of the enameled wire and the gaps between the round wires are inevitable. Therefore, this lower slot fill rate usually leads to lower current input, thereby limiting the torque output capacity of the motor. In addition, for the solution of not placing the winding at the slot, although the eddy current loss of the winding is reduced, some slot space is vacated, which will also result in a lower slot fill rate of the high-speed motor. Summary of the invention

[0004] In order to overcome the deficiencies of the prior art, the purpose of the present invention is to provide a low eddy current loss oblate hybrid wire winding configuration structure, which can reduce the winding eddy current loss while increasing the winding slot rate and improving the torque output capacity of the motor.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A low eddy current loss flat-round hybrid wire winding configuration structure comprises a round wire winding, a flat wire winding and a heat dissipation pipe arranged in a stator tooth slot, wherein the round wire winding is wound on one side of the slot opening of the stator tooth slot, the heat dissipation pipe is arranged in the middle of one side of the slot bottom of the stator tooth slot, and the flat wire winding is wound on one side of the slot bottom of the stator tooth slot and is located on both sides of the heat dissipation pipe.

[0007] As a preferred solution of the above motor, the gaps between the round wire winding, the flat wire winding and the heat dissipation pipe are filled with thermal conductive silicone grease.

[0008] As a preferred solution of the above motor, the heat dissipation pipe is made of aluminum, copper, aluminum alloy or copper alloy.

[0009] As a preferred solution of the above motor, the heat dissipation pipeline is connected to a coolant supply system capable of conveying coolant therein.

[0010] As a preferred solution of the above motor, a heat conducting rod is inserted into the heat dissipation pipe.

[0011] As a preferred solution of the above motor, the cross-sectional shape of the heat dissipation pipe is an isosceles triangle.

[0012] Compared with the prior art, it has the following beneficial effects:

[0013] The low eddy current loss flat circular hybrid wire winding configuration structure of the embodiment of the present invention comprises a round wire winding, a flat wire winding and a heat dissipation pipe configured in the stator tooth slot, wherein the round wire winding is wound on one side of the slot of the stator tooth slot, the heat dissipation pipe is arranged in the middle of the slot bottom side of the stator tooth slot, the flat wire winding is wound on one side of the slot bottom of the stator tooth slot and is located on both sides of the heat dissipation pipe, that is, a round enameled wire with a fine wire diameter is used in the high-frequency leakage magnetic field area of ​​the slot to reduce the eddy current loss of the winding, a flat wire with a larger cross-sectional area is used in the slot bottom area to increase the slot fill rate of the winding, and the triangular area between the flat wires is used to insert the heat dissipation pipe to directly cool the stator and its winding; it can be seen that the low eddy current loss flat circular hybrid wire winding configuration structure implementing the embodiment of the present invention can reduce the eddy current loss of the winding while increasing the slot fill rate of the winding, thereby improving the torque output capacity of the motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings of the embodiment are briefly introduced below.

[0015] Figure 1 It is a structural diagram of the traditional high-speed motor winding configuration structure;

[0016] Figure 2 2 is a schematic structural diagram of a low eddy current loss oblate hybrid wire winding configuration structure according to an embodiment of the present invention;

[0017] Figure 3 It is a magnetic flux density distribution cloud diagram of a slot area of ​​a high-speed motor to which a low eddy current loss oblate hybrid wire winding configuration structure according to an embodiment of the present invention is applied;

[0018] Figure 4 This is a graph showing the eddy current loss versus time for a conventional round enameled wire winding configuration;

[0019] Figure 5 This is a graph showing the eddy current loss variation over time for the oblate hybrid wire winding configuration.

[0020] Markings in the figure:

[0021] 1. Round wire winding; 2. Flat wire winding; 3. Heat dissipation duct. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] like Figure 2 Shown is a preferred embodiment of the present invention.

[0024] A low eddy current loss flat round hybrid wire winding configuration structure includes a round wire winding 1, a flat wire winding 2 and a heat dissipation pipe 3 arranged in a stator tooth slot, wherein the round wire winding 1 is wound on one side of the slot of the stator tooth slot, the heat dissipation pipe 3 is arranged in the middle of one side of the slot bottom of the stator tooth slot, and the flat wire winding 2 is wound on one side of the slot bottom of the stator tooth slot and is located on both sides of the heat dissipation pipe 3. Wherein, the cross-sectional shape of the heat dissipation pipe 3 is an isosceles triangle. Therefore, the high-frequency leakage magnetic field area of ​​the slot uses a round enameled wire with a fine wire diameter to reduce the eddy current loss of the winding, the bottom area of ​​the slot uses a flat wire with a larger cross-sectional area to increase the slot full rate of the winding, and the triangular area enclosed by the flat wire is used to insert the heat dissipation pipe 3 to directly cool the stator and its winding; it can be seen that the low eddy current loss flat round hybrid wire winding configuration structure of the embodiment of the present invention can reduce the eddy current loss of the winding while increasing the slot full rate of the winding and improving the torque output capacity of the motor.

[0025] Exemplarily, the gaps between the round wire winding 1, the flat wire winding 2 and the heat dissipation pipe 3 are filled with thermal grease to reduce the contact thermal resistance between the three and improve the thermal conductivity and heat dissipation capacity of the system.

[0026] Exemplarily, the heat dissipation pipe 3 is preferably made of a material with high thermal conductivity, such as aluminum, copper, aluminum alloy or copper alloy.

[0027] For example, in order to timely remove the heat from the winding, the heat dissipation pipe 3 can be connected to a coolant supply system that can deliver coolant therein, or a heat conducting rod can be inserted therein.

[0028] like Figure 3 As shown in the figure, it is a magnetic flux density distribution cloud diagram of the slot area of ​​a high-speed motor using the low eddy current loss flat round hybrid wire winding configuration structure of the embodiment of the present invention. It can be clearly seen that the magnetic field at the slot is much lower than the magnetic flux density in the slot bottom area. Therefore, placing a flat wire with a large cross-sectional area at the bottom of the slot will not cause large eddy current losses. In addition, in order to avoid the skin effect of the square wire after passing the high-frequency AC current, the flat wire can be further subdivided so that the length of its longest side is less than the skin depth.

[0029] Conventional high-speed motor winding configurations, such as Figure 1 As shown, both are wound with round enameled wires of relatively thin wire diameter. Therefore, it has the advantages of small winding eddy current loss and skin effect loss, but the slot fill rate is low. In order to illustrate the advantages of the flat round hybrid wire winding configuration structure proposed in the embodiment of the present invention, the two winding configurations were compared by finite element simulation, and the results are as follows:

[0030] like Figure 4 and Figure 5 As shown in the figure, the eddy current loss of the traditional round enameled wire configuration structure and the flat round hybrid wire winding configuration structure is basically the same, and the latter is slightly lower than the former. In detail, the average eddy current loss of the traditional round enameled wire configuration structure is 8.6*24W (24 slots), while the average eddy current loss of the flat round hybrid wire winding configuration structure is 7.3*24W. In addition, the copper full rate of the flat round hybrid wire winding configuration structure is about 43.12%, while the copper full rate of the traditional round enameled wire configuration structure is about 36.28%; that is, the copper full rate of the flat round hybrid wire winding configuration structure is increased by 18.85%.

[0031] The flat mixed wire winding configuration structure allows the stator slots to accommodate enough wires while leaving some space ( Figure 2 Therefore, the heat dissipation pipe can be directly inserted into the winding through the triangular area, which is beneficial to direct heat dissipation of the winding and provides favorable conditions for improving the torque output of the high-speed motor.

[0032] In the description of the present invention, it should be understood that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" used in the present invention should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0033] The above disclosure is only a preferred embodiment of the present invention, which certainly cannot be used to limit the scope of rights of the present invention. Therefore, equivalent changes made according to the scope of the patent application of the present invention are still within the scope covered by the present invention.

Claims

1. Low eddy current loss oblate hybrid wire winding configuration structure, characterized by: The invention comprises a round wire winding, a flat wire winding and a heat dissipation pipe arranged in a stator tooth slot. The round wire winding is wound on one side of the slot opening of the stator tooth slot, the heat dissipation pipe is arranged in the middle of one side of the slot bottom of the stator tooth slot, and the flat wire winding is wound on one side of the slot bottom of the stator tooth slot and is located on both sides of the heat dissipation pipe.

2. The low eddy current loss oblate hybrid wire winding configuration structure according to claim 1, characterized in that: The gaps between the round wire winding, the flat wire winding and the heat dissipation pipeline are filled with thermal conductive silicone grease.

3. The low eddy current loss oblate hybrid wire winding configuration structure according to claim 1, characterized in that: The heat dissipation pipe is made of aluminum, copper, aluminum alloy or copper alloy.

4. The low eddy current loss oblate hybrid wire winding configuration structure according to claim 1, characterized in that: The heat dissipation pipeline is connected to a coolant supply system capable of conveying coolant therein.

5. The low eddy current loss oblate hybrid wire winding configuration structure according to claim 1, characterized in that: A heat conducting rod is inserted into the heat dissipation pipeline.

6. The low eddy current loss oblate hybrid wire winding configuration structure according to claim 1, characterized in that: The cross-sectional shape of the heat dissipation pipe is an isosceles triangle.

Images