Composite oil cooling structure of permanent magnet motor

Abstract

The utility model discloses a composite oil cooling structure of a permanent magnet motor, relates to the technical field of permanent magnet motors, and solves the technical problems of temperature accumulation and local hot spot formation caused by temperature gradient due to thermal resistance of a motor coil. Comprising a motor housing; a rotor cooling member installed inside the motor housing; the coil cooling component is arranged between the rotor cooling component and the motor shell in a sleeving manner; the rotor cooling component comprises a central shaft penetrating through the motor shell, and a cooling oil cavity is formed in the central shaft; according to the utility model, the rotor cooling component and the coil cooling component are combined, so that heat of the coil body and the rotor core is directly and effectively taken away, and adverse consequences of motor insulation failure and magnetic steel excitation loss caused by heat accumulation and local hot spot formation are avoided, the power density of the motor can be further improved, and the service life of the motor is prolonged. Good heat dissipation provides necessary guarantee for the low-voltage and high-power motor.

Description

Technical Field

[0001] The utility model belongs to the technical field of permanent magnet motors, in particular to a composite oil cooling structure of a permanent magnet motor. Background Art

[0002] A magneto oil cooling system typically consists of an oil cooler housing, an oil pump, a radiator, piping, and other components. The operating principle is that, driven by the oil pump, cooling oil flows through the motor housing, absorbs heat from the motor, and then returns to the radiator, dissipating the heat into the atmosphere. This effectively diverts heat away from the motor's surface and dissipates it to a dedicated radiator. This offers two advantages. First, it improves heat dissipation efficiency; the combined heat dissipation efficiency of the radiator and oil far exceeds that of the motor itself. Second, the motor can be made very small, meeting the requirements of a compact installation, and the radiator can be installed in a well-ventilated area away from the motor. Oil cooling offers superior heat dissipation compared to water cooling. Furthermore, cooling oil is partially non-magnetic and non-conductive, providing enhanced protection for motor operation.

[0003] Whether it is water cooling or oil cooling, the existing liquid cooling method requires the heat source inside the motor to be transferred to the external shell through layers of materials and then carried away by the oil channel. For example, the coil inside the motor coil has a temperature gradient from the coil to the oil cooling shell due to the existence of thermal resistance. The coil cannot be cooled directly, resulting in temperature accumulation and the formation of local hot spots. Utility Model Content

[0004] The utility model aims to solve at least one of the technical problems existing in the prior art; to this end, the utility model proposes a composite oil cooling structure for a permanent magnet motor.

[0005] A composite oil cooling structure for a permanent magnet motor, comprising:

[0006] Motor housing;

[0007] A rotor cooling member mounted inside the motor housing;

[0008] A coil cooling member is sleeved and installed between the rotor cooling member and the motor housing;

[0009] The rotor cooling member includes a central shaft penetrating the motor housing, and a cooling oil cavity is formed inside the central shaft;

[0010] The coil cooling component includes a coil body sleeved on a central axis, a plurality of cooling oil channels are evenly arranged on the outer circumferential surface of the coil body, and cooling oil spray rings are arranged inside both ends of the coil body.

[0011] Preferably, the rotor cooling component further comprises a rotor core sleeved on the central shaft, the right end of the central shaft passes through the motor housing and is exposed to the outside, and a heat sink is provided on the right end of the central shaft.

[0012] Preferably, the coil cooling component includes a plurality of oil drain holes opened on the surface of the cooling oil spray ring, and the upper surface of the cooling oil spray ring is provided with an oil spray ring oil inlet pipe penetrating the coil body and exposed to the outside.

[0013] Preferably, two oil outlet pipes are provided on the upper surface of the coil body, and a plurality of cooling oil channels are connected to each other.

[0014] Preferably, an oil channel communicating with the cooling oil chamber is opened at the left end of the central shaft.

[0015] Preferably, the cooling oil spray ring is located at the end of the rotor core, and the oil drain holes are distributed laterally.

[0016] Preferably, the motor housing includes end covers provided at both ends, and the upper surface of the end covers is provided with two oil injection ring oil filling ports connected to two oil injection ring oil inlet pipes.

[0017] Preferably, a cooling oil filling port and a cooling oil drain port are respectively provided on the upper surface of the motor housing, and bottom oil collecting ports are provided at both ends of the motor housing near the bottom.

[0018] Compared with the prior art, the beneficial effects of the present invention are:

[0019] (1) The present invention combines the rotor cooling component and the coil cooling component to directly and effectively remove the heat from the coil body and the rotor core, avoiding heat accumulation and the formation of local hot spots, which would cause the adverse consequences of motor insulation failure and magnetic demagnetization. The motor power density can be further improved, and good heat dissipation provides the necessary guarantee for low-voltage and high-power motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 This is a structural diagram of the oil cooling structure of the permanent magnet motor of the utility model;

[0021] Figure 2 This is a cross-sectional view of the oil cooling structure of the permanent magnet motor of the utility model;

[0022] Figure 3 For this utility model Figure 2 A cross-sectional view of the middle rotor cooling member;

[0023] Figure 4 For this utility model Figure 2 Schematic diagram of the structure of the middle coil cooling component;

[0024] Figure 5 For this utility model Figure 4 Schematic diagram of the structure of the intermediate cooling oil injection ring;

[0025] In the figure: 100, motor housing; 101, end cover; 102, oil injection ring oil filling port; 103, cooling oil oil filling port; 104, bottom oil collecting port; 105, cooling oil drain port; 200, rotor cooling component; 201, center shaft; 202, cooling oil cavity; 203, rotor core; 204, heat sink; 300, coil cooling component; 301, coil body; 302, cooling oil channel; 303, oil outlet pipe; 304, cooling oil injection ring; 305, oil injection ring oil inlet pipe; 306, oil drain hole. DETAILED DESCRIPTION

[0026] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments. Obviously, the embodiments described are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0027] Example 1

[0028] See also Figure 3 - Figure 5 The present application provides a composite oil cooling structure for a permanent magnet motor, specifically a direct cooling structure, wherein the direct cooling structure includes a rotor cooling component 200 and a coil cooling component 300, including:

[0029] Motor housing 100;

[0030] The rotor cooling member 200 is installed inside the motor housing 100. The rotor cooling member 200 utilizes the rotor core 203 in the middle of the motor shaft, which generates relatively high heat, to directly contact the central shaft 201. Heat is transferred to the cooling oil through the central shaft 201. The cooling oil flows throughout the central shaft 201, dissipating the heat to the lower temperature locations at both ends of the central shaft 201. Furthermore, the heat dissipation ribs at the rear end dissipate the heat from the central shaft 201 to the surrounding environment in a timely manner, thereby ensuring that the magnets do not lose magnetism due to overheating.

[0031] The coil cooling member 300 is installed between the rotor cooling member 200 and the motor housing 100. The coil cooling member 300 sprays cooling oil on the winding ends to cool the windings. Under the action of gravity, the oil gradually flows to the bottom oil collection port 104 at the bottom of the base. After flowing out of the oil collection pipe and returning to the cooling system for cooling, the reciprocating cycle cools the coil body 301 and the rotor core 203.

[0032] The rotor cooling member 200 includes a central shaft 201 that passes through the motor housing 100. A cooling oil cavity 202 is defined within the central shaft 201 to facilitate the filling of the entire cooling oil cavity 202 with cooling oil, thereby cooling the central shaft 201 from the inside.

[0033] The coil cooling component 300 includes a coil body 301 sleeved on the central axis 201, and a plurality of cooling oil channels 302 are evenly arranged on the outer circumferential surface of the coil body 301. The inner arc surface of the cooling oil channel 302 is provided with oil holes to facilitate the cooling oil to be sprayed out from the oil holes. Cooling oil spray rings 304 are arranged inside the two ends of the coil body 301. The cooling oil spray rings 304 spray the cooling oil onto the end of the rotor core 203, thereby cooling the rotor core 203.

[0034] In this embodiment, preferably, the rotor cooling component 200 also includes a rotor core 203 sleeved on the central shaft 201, the right end of the central shaft 201 passes through the motor housing 100 and is exposed to the outside, and a heat sink 204 is provided at the right end of the central shaft 201 to dissipate heat and cool the central shaft 201.

[0035] In this embodiment, preferably, the coil cooling component 300 includes a plurality of oil drain holes 306 opened on the surface of the cooling oil spray ring 304 to facilitate the discharge of cooling oil. The upper surface of the cooling oil spray ring 304 is provided with an oil spray ring oil inlet pipe 305 that passes through the coil body 301 and is exposed to the outside.

[0036] In this embodiment, preferably, two oil outlet pipes 303 are provided on the upper surface of the coil body 301, and the two oil outlet pipes 303 are respectively connected to the cooling oil filling port 103 and the cooling oil drain port 105, and multiple cooling oil channels 302 are connected to each other to facilitate the circulation of cooling oil.

[0037] In this embodiment, preferably, an oil passage communicating with the cooling oil chamber 202 is opened at the left end of the central shaft 201 to facilitate the introduction of cooling oil into the interior of the central shaft 201 .

[0038] In this embodiment, preferably, the cooling oil spray ring 304 is located at the end of the rotor core 203, and the oil drain holes 306 are distributed laterally.

[0039] In summary, the cooling oil enters the cooling oil channel 302 and the oil outlet pipe 303 for injecting cooling oil at a certain pressure by the oil pump, and is sprayed on the end of the winding to cool the winding. Under the action of gravity, it gradually flows to the bottom oil collecting port 104 at the bottom of the machine base, flows out of the oil collecting pipe and returns to the cooling system for cooling, and then circulates back and forth to cool the winding and the rotor core 203.

[0040] The rotor cooling structure 200 features a hollow central shaft 201, with cooling oil injected into the cooling oil chamber 202. Heat dissipation ribs are evenly distributed along the shaft's tail end. During motor operation, the rotor core 203, located in the center of the central shaft 201 and generating the most heat, comes into direct contact with the shaft. Heat is transferred through the shaft to the cooling oil. The cooling oil flows throughout the shaft, dispersing the heat toward the cooler ends. Meanwhile, the heat dissipation ribs at the tail end dissipate the heat to the surrounding environment, preventing the magnets from overheating and demagnetizing.

[0041] Example 2

[0042] Reference Figure 1 and Figure 2 , which is the second embodiment of the present utility model, is for cooling the housing of the motor, and the housing cooling utilizes the oil channel of the machine base for cooling.

[0043] In this embodiment, preferably, the motor housing 100 includes end covers 101 arranged at both ends, and two oil injection ring oil filling ports 102 connected to two oil injection ring oil inlet pipes 305 are provided on the upper surface of the end cover 101. A base is provided at the bottom of the motor housing 100, and a return oil channel is opened inside the base to facilitate the flow and collection of cooling oil. A cooling oil filling port 103 and a cooling oil drain port 105 are respectively provided on the upper surface of the motor housing 100 to facilitate the injection and discharge of cooling oil. Bottom oil collecting ports 104 are provided near the bottom of both ends of the motor housing 100, and the bottom oil collecting port 104 is connected to the external oil collecting pipe, and the oil collecting pipe is connected to the recovery system.

[0044] In summary, the engine base oil channel cooling utilizes the return oil channel designed in the engine base cavity to allow the cooling oil to flow through the motor housing 100 in an orderly manner, taking away the heat generated by the motor operation, and then cooling the oil through an external cooling system, thus repeating the cycle.

[0045] Example 3

[0046] This embodiment is obtained by combining the first embodiment and the second embodiment.

[0047] The above composite cooling method of direct cooling and shell cooling can fully remove the heat from the motor and ensure the stable operation of the permanent magnet motor.

[0048] The above embodiments are only used to illustrate the technical method of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A composite oil cooling structure for a permanent magnet motor, characterized in that: include: Motor housing (100); a rotor cooling member (200) installed inside the motor housing (100); A coil cooling component (300) is sleeved and installed between the rotor cooling component (200) and the motor housing (100); The rotor cooling component (200) comprises a central shaft (201) penetrating the motor housing (100), and a cooling oil cavity (202) is provided inside the central shaft (201); The coil cooling component (300) comprises a coil body (301) sleeved on a central axis (201), a plurality of cooling oil channels (302) being evenly arranged on the outer circumferential surface of the coil body (301), and cooling oil spray rings (304) being arranged inside both ends of the coil body (301).

2. The composite oil cooling structure of a permanent magnet motor according to claim 1, characterized in that: The rotor cooling component (200) further comprises a rotor core (203) sleeved on the central shaft (201); the right end of the central shaft (201) passes through the motor housing (100) and is exposed to the outside; and a heat sink (204) is provided on the right end of the central shaft (201).

3. The composite oil cooling structure of a permanent magnet motor according to claim 2, characterized in that: The coil cooling component (300) includes a plurality of oil drain holes (306) provided on the surface of a cooling oil spray ring (304). The upper surface of the cooling oil spray ring (304) is provided with an oil spray ring oil inlet pipe (305) that penetrates the coil body (301) and is exposed to the outside.

4. The composite oil cooling structure of a permanent magnet motor according to claim 3, characterized in that: Two oil outlet pipes (303) are provided on the upper surface of the coil body (301), and a plurality of cooling oil channels (302) are connected to each other.

5. The composite oil cooling structure of a permanent magnet motor according to claim 3, characterized in that: An oil passage communicating with the cooling oil cavity (202) is provided at the left end of the central shaft (201).

6. The composite oil cooling structure of a permanent magnet motor according to claim 3, characterized in that: The cooling oil spray ring (304) is located at the end of the rotor core (203), and the oil drain holes (306) are distributed laterally.

7. The composite oil cooling structure of a permanent magnet motor according to claim 3, characterized in that: The motor housing (100) comprises end covers (101) provided at both ends, and the upper surface of the end cover (101) is provided with two oil injection ring oil filling ports (102) communicating with two oil injection ring oil inlet pipes (305).

8. The composite oil cooling structure of a permanent magnet motor according to claim 5, characterized in that: The upper surface of the motor housing (100) is provided with a cooling oil filling port (103) and a cooling oil drain port (105), and both ends of the motor housing (100) are provided with bottom oil collecting ports (104) near the bottom.

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