A high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps

Abstract

This utility model discloses a high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps, relating to the field of permanent magnet direct-drive motor technology. It includes a frame, a motor, and a powerful cooling fan. This utility model employs permanent magnet direct-drive variable frequency technology, eliminating rotor losses in the motor, significantly improving the power factor, and increasing efficiency by 10%-15% compared to traditional motors. This effectively reduces energy consumption and fully complies with national energy conservation and emission reduction requirements. It eliminates the traditional speed-changing mechanism, directly driving the mud pump and avoiding transmission losses from belts, chains, and other components. Compared to traditional transmission methods, transmission efficiency can be significantly improved by 15%-20%, greatly enhancing the overall working efficiency of the mud pump. This utility model has a simple structure, reducing a large number of transmission components and vulnerable parts, lowering the frequency and difficulty of maintenance and repair. The motor adopts a fully enclosed design with a high protection level, effectively preventing dust, moisture, and other external impurities from entering the motor, further ensuring its reliability.

Description

Technical Field

[0001] This utility model relates to the field of permanent magnet direct drive motor technology, specifically a high-efficiency direct drive variable frequency permanent magnet motor for mud pumps. Background Technology

[0002] In the oil drilling industry, the mud pump drive of electric drilling rigs has traditionally relied on AC / DC variable speed motors paired with drive belts or chains. However, with the widespread application of electric drilling rigs in this industry, users have placed higher demands on equipment performance and maintenance: they want to reduce or eliminate the speed change mechanism, improve equipment efficiency, reduce maintenance intensity, and increase load capacity. Traditional solutions have several shortcomings: the use of a speed change mechanism complicates the structure, increases rotational inertia, reduces overall efficiency, increases noise, causes lubricant leaks, and requires frequent maintenance, causing considerable inconvenience to users.

[0003] Low-speed, high-torque direct-drive motors have emerged, eliminating bulky transmission belts or chains and effectively avoiding many adverse effects of reduction mechanisms, such as complex structure, large moment of inertia, reduced efficiency, increased noise, lubricant leakage, and frequent maintenance. They can meet the requirements of constant torque and constant power, making them an ideal replacement for traditional electric motors with speed-changing mechanisms.

[0004] Low-speed, high-torque direct-drive motors are mainly divided into two categories: AC asynchronous direct-drive motors and permanent magnet synchronous direct-drive motors. Among them, permanent magnet synchronous direct-drive motors, due to the absence of rotor losses, possess a higher power factor and efficiency, making them more aligned with national energy conservation, emission reduction, and green driving development requirements. Compared to AC asynchronous direct-drive motors, permanent magnet synchronous direct-drive motors also have significant advantages in terms of smaller size and lighter weight.

[0005] Among them, permanent magnet synchronous direct drive motors, due to the absence of rotor losses, have higher power factors and efficiency, making them more in line with national requirements for energy conservation, emission reduction, and green driving. Compared to AC asynchronous direct drive motors, permanent magnet synchronous direct drive motors also have significant advantages in terms of smaller size and lighter weight. Utility Model Content

[0006] The purpose of this utility model is to provide a high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps, so as to solve the problems mentioned in the background art, such as the use of a speed change mechanism that makes the structure more complicated, increases the moment of inertia, reduces the overall efficiency, increases noise, causes lubricating oil leakage, and requires frequent maintenance, which brings many inconveniences to users.

[0007] To achieve the above objectives, this utility model provides the following technical solution: a high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps, comprising a base and a motor mounted on its top, with a powerful cooling fan mounted on the top of the motor; the base is welded from a steel structure; the motor includes a cylindrical motor housing mounted on the base and a motor shaft mounted at its center; a rotor core is fixedly mounted at the middle position of the motor shaft, and a high-performance permanent magnet is disposed within it; bearings are interference-fitted onto both sides of the rotor core on the motor shaft, and the outer rings of the two bearings... The motor housing is equipped with a stator core containing stator coils. A disc-shaped front cover is located on the outer ring of the bearing at the front end, and a disc-shaped rear cover is located on the outer ring of the bearing at the rear end. The front and rear covers are respectively connected and fixed to both ends of the motor housing. The forced cooling fan includes a fan housing connected to the motor housing. The fan housing is connected to the inside of the motor housing through an air duct, and a fan motor is located at the center of its top surface. An exhaust port is provided on the side wall of the fan housing, and an air filter box communicating with the inside of the motor housing is provided at the bottom of the motor housing.

[0008] Preferably, the motor housing is welded from low-temperature resistant steel plate, and multiple air duct support ribs are provided in the circumferential direction inside it.

[0009] Preferably, the motor shaft is welded from high-strength alloy steel, and one end of it is directly connected to the drive shaft of the mud pump via a flexible coupling.

[0010] Preferably, the rotor core adopts an internal structure and is fully enclosed with high-performance permanent magnets, which are arranged in a V-shape; the rotor core is made of cold-rolled silicon steel sheets with high magnetic permeability and low loss, and the rotor laminations are deburred before lamination.

[0011] Preferably, the surface of the high-performance permanent magnet is zinc-plated.

[0012] Preferably, the bearing is a high-performance imported bearing, and the bearing adopts a sealed structure and is filled with high-performance grease.

[0013] Preferably, the stator core is made of high-permeability, low-loss cold-rolled silicon steel sheets, and the stator laminations are deburred before lamination. The stator core is equipped with H-class insulated, high-strength, energy-saving magnetic slot wedges.

[0014] Preferably, the stator coil is made of high-purity oxygen-free copper material, combined with corona-resistant Class H insulation material, and is subjected to VPI vacuum impregnation; the surfaces of both ends of the stator coil are coated with conformal coating.

[0015] Preferably, one or two of the forced-cooling fans are installed on the top of the motor housing.

[0016] Preferably, the powerful cooling fan adopts variable frequency speed control.

[0017] Compared with the prior art, the beneficial effects of this utility model are:

[0018] 1. This utility model adopts permanent magnet direct drive frequency conversion technology, which eliminates rotor loss in the motor, significantly improves the power factor, and increases efficiency by 10%-15% compared to traditional motors. It effectively reduces energy consumption, fully complies with national energy conservation and emission reduction requirements, saves users a lot of energy costs in the long-term use, and also makes a positive contribution to environmental protection.

[0019] 2. This utility model eliminates the traditional speed-changing mechanism, directly driving the mud pump and avoiding transmission losses from components such as drive belts and chains. Compared with traditional transmission methods, transmission efficiency can be significantly improved by 15%-20%, greatly enhancing the overall working efficiency of the mud pump. This allows the equipment to complete its work tasks more efficiently during operation, increasing production efficiency and creating higher economic value for users.

[0020] 3. This utility model has a simple structure, reducing a large number of transmission components and vulnerable parts, thus lowering the frequency and difficulty of maintenance and repair. The maintenance intensity for workers is significantly reduced, and the maintenance cost of the equipment is also significantly decreased. This means that users can reduce downtime caused by maintenance during equipment use, improve equipment utilization, reduce worker workload, and enhance overall work efficiency and equipment reliability.

[0021] 4. This utility model features small size, light weight, simple structure, and excellent and reliable performance. This not only facilitates the installation and transportation of the equipment, but also makes the entire mud pump system more compact, occupies less space, and can better adapt to different working environments and installation conditions, thus improving the equipment's versatility and flexibility;

[0022] 5. The electric motor of this utility model adopts a fully enclosed design with a high protection level, which can effectively prevent dust, moisture and other external impurities from entering the motor, further ensuring the reliability of the motor. In harsh working environments, such as oil drilling sites, this high protection level design can ensure the long-term stable operation of the motor, reduce failures and damage caused by environmental factors, extend the service life of the motor, and reduce equipment replacement costs;

[0023] 6. The electric motor of this invention adopts a suction cooling method. A fan draws air from the top of the motor, creating a negative pressure inside the motor. This ensures that cooling airflow passes through all air paths, resulting in a relatively uniform internal temperature and better heat dissipation. Good heat dissipation performance is crucial for the stable operation of the electric motor, effectively preventing malfunctions due to overheating, improving the motor's operational reliability and safety, and ensuring the stable performance of the equipment under long-term, high-load operating conditions. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the present invention;

[0025] Figure 2 for Figure 1 Structural diagram;

[0026] In the diagram: Frame-1, Motor-2, Motor housing-21, Motor shaft-22, Rotor core-23, High-performance permanent magnet-24, Bearing-25, Stator core-26, Stator coil-27, Front cover-28, Rear cover-29, Powerful cooling fan-3, Fan housing-31, Fan motor-32, Exhaust vent-33, Air filter box-34. Detailed Implementation

[0027] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings and specific embodiments.

[0028] Please refer to Figure 1-2 , Figure 1 This is a schematic diagram of the present invention; Figure 2 for Figure 1 Structural diagram.

[0029] This utility model provides a high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps, which is particularly suitable for the driving needs of mud pumps under harsh working conditions such as oil drilling; it includes a base 1, a motor 2 is mounted on the top of the base 1, and a powerful cooling fan 3 is mounted on the top of the motor 2.

[0030] The base 1 is made of welded steel structure, and an electric motor 2 is installed on its top surface.

[0031] The motor 2 includes a cylindrical motor housing 21 mounted on the base 1. A motor shaft 22 is mounted at the center of the motor housing 21. A rotor core 23 is fixedly mounted at the middle of the motor shaft 22. The rotor core 23 has an internal structure with a high-performance permanent magnet 24. Bearings 25 are interference-fitted on both sides of the rotor core 23. A stator core 26 is mounted on the outer ring of the two bearings 25. A stator coil 27 is mounted inside the stator core 26. A disc-shaped front cover 28 is mounted on the outer ring of the bearing 25 at the front end, and a disc-shaped rear cover 29 is mounted on the outer ring of the bearing 25 at the rear end. The front cover 28 and the rear cover 29 are respectively connected and fixed to both ends of the motor housing 21. A powerful cooling fan 3 is also mounted on the top of the motor housing 21.

[0032] The motor housing 21 is welded from low-temperature resistant steel plate and has multiple air duct support ribs arranged in the circumferential direction inside, which gives the motor housing 21 good mechanical strength, can withstand the vibration and external impact during the operation of the motor 2, and also has the advantages of light weight and good heat dissipation performance.

[0033] The motor shaft 22 is welded from high-strength alloy steel using advanced welding technology to ensure its quality and strength. The motor shaft 22 undergoes a special heat treatment process, giving it high strength and good toughness, enabling it to withstand the large torque and vibration generated during the operation of the mud pump. One end of the motor shaft 22 is directly connected to the drive shaft of the mud pump via a flexible coupling, realizing direct drive between the motor and the mud pump.

[0034] The rotor core 23 is made of cold-rolled silicon steel sheets with high magnetic permeability and low loss. Before the rotor laminations are laminated, a deburring process is performed to improve the lamination lamination coefficient, which can reduce the electromagnetic noise and vibration of the motor.

[0035] The high-performance permanent magnet 24 is completely enclosed inside the rotor core 23 and arranged in a V-shape. The complete enclosure of the high-performance permanent magnet 24 effectively prevents it from being disturbed by external magnetic fields and mechanically damaged. Furthermore, the surface of the high-performance permanent magnet 24 is galvanized, which improves its corrosion resistance. The V-shaped arrangement of the high-performance permanent magnet 24 can optimize the air gap magnetic field distribution of the motor, thereby improving the power density and operating efficiency of the motor. The high-performance permanent magnet 24 has high remanence, high coercivity, and high maximum operating temperature, thus ensuring that the motor has a strong anti-demagnetization capability and can generate a strong and stable magnetic field.

[0036] The bearing 25 is a high-performance imported bearing. This bearing features rolling element guidance, a large oil gap, and a copper cage. This type of bearing effectively reduces the rotor's rotational friction resistance, improving the motor's operating efficiency and service life. The bearing 25 employs a sealed structure and is internally filled with high-performance grease, which reduces bearing wear and friction, and lowers the bearing's operating temperature.

[0037] The stator core 26 is made of high-permeability, low-loss cold-rolled silicon steel sheets. Before the stator laminations are laminated, a deburring process is performed to improve the lamination lamination coefficient, effectively reduce eddy current losses between laminations, and reduce electromagnetic noise and vibration of the motor. The stator core 26 is equipped with H-class insulated high-strength energy-saving magnetic slot wedges, which makes the air gap magnetic field distribution of the motor more uniform, reduces magnetic field pulsation and stator iron loss, improves motor efficiency, and reduces motor temperature rise. At the same time, the magnetic slot wedges also play a role in reducing motor noise and vibration.

[0038] The stator coil 27 is made of high-purity oxygen-free copper material, combined with corona-resistant Class H insulation material, and undergoes VPI vacuum impregnation to enhance the insulation strength of the motor winding and the thermal conductivity between the coil and the stator core. The surfaces at both ends of the stator coil 27 are coated with conformal coating to improve the safety factor of the winding.

[0039] One or two forced-air cooling fans 3 are installed on the top of the motor housing 21. Each fan housing 31 is connected to the motor housing 21. The fan housing 31 is connected to the inside of the motor housing 21 through a specific air duct design, and a fan motor 32 is installed at the center of its top surface. An exhaust port 33 is provided on the side wall of the fan housing 31. At the same time, an air filter box 34 communicating with the inside of the motor housing 21 is provided at the bottom of the motor housing 21. During the operation of the motor 2, the forced-air cooling fan 3 can introduce external cold air into the motor 2. The cold air flows in the air duct inside the motor 2, carrying away the heat generated by the loss inside the motor 2, and then is discharged through the exhaust port. The air duct design has been optimized through fluid dynamics simulation design and field test to ensure that the cold air can be evenly distributed inside the motor 2, improving the heat dissipation effect of the motor 2 and ensuring effective cooling of the motor 2.

[0040] The powerful cooling fan 3 can also adopt frequency conversion speed control, which can automatically adjust the fan speed according to the load and temperature of the motor 2, so as to reduce the loss of the powerful cooling fan 3 while ensuring the heat dissipation effect of the main motor 2.

[0041] The use of the air filter box 34 can effectively filter inlet sand and insects, ensuring the cleanliness of the air inside the motor 2.

[0042] Although embodiments of the present invention have been shown and described, it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, it will be understood by those skilled in the art that all other embodiments obtained by making various changes, modifications, substitutions and alterations to these embodiments without departing from the principles and spirit of the present invention and without creative effort are within the scope of protection of the present invention.

Claims

1. A high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps, characterized by: The device includes a base (1) and a motor (2) mounted on top of it. A powerful cooling fan (3) is mounted on top of the motor (2). The base (1) is welded from steel. The motor (2) includes a cylindrical motor housing (21) mounted on the base (1) and a motor shaft (22) mounted at its center. A rotor core (23) is fixedly mounted at the middle position of the motor shaft (22) and a high-performance permanent magnet (24) is mounted inside it. Bearings (25) are interference-fitted on both sides of the rotor core (23) of the motor shaft (22). A stator core (26) is mounted on the outer ring of the two bearings (25) and a stator coil (27) is mounted inside it. A disc-shaped front cover (28) is provided on the outer ring of the bearing (25) at the front end, and a disc-shaped rear cover (29) is provided on the outer ring of the bearing (25) at the rear end. The front cover (28) and the rear cover (29) are respectively connected and fixed to both ends of the motor housing (21). The forced cooling fan (3) includes a fan housing (31) connected to the motor housing (21). The fan housing (31) is connected to the inside of the motor housing (21) through a duct and a fan motor (32) is provided at the center of its top surface. An exhaust port (33) is provided on the side wall of the fan housing (31). An air filter box (34) communicating with the inside of the motor housing (21) is provided at the bottom of the motor housing (21).

2. The high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps according to claim 1, characterized in that: The motor housing (21) is made of low-temperature resistant steel plate and has multiple air duct support ribs in the circumferential direction inside.

3. The high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps according to claim 2, characterized in that: The motor shaft (22) is made of high-strength alloy steel and welded together. One end of the shaft is directly connected to the drive shaft of the mud pump through a flexible coupling.

4. The high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps according to claim 3, characterized in that: The rotor core (23) adopts an internal structure and is fully enclosed with high-performance permanent magnets (24), which are arranged in a V-shape. The rotor core (23) is made of cold-rolled silicon steel sheets with high magnetic permeability and low loss. The rotor laminations are deburred before being stacked.

5. The high-efficiency direct-drive variable frequency permanent magnet motor for mud pumps according to claim 4, characterized in that: The high-performance permanent magnet (24) is zinc-plated.

6. The high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps according to claim 5, characterized in that: The bearing (25) is a high-performance imported bearing. The bearing (25) adopts a sealed structure and is filled with high-performance grease.

7. The high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps according to claim 6, characterized in that: The stator core (26) is made of cold-rolled silicon steel sheets with high magnetic permeability and low loss. The stator laminations are deburred before being stacked. The stator core (26) is equipped with H-class insulated high-strength energy-saving magnetic slot wedges.

8. The high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps according to claim 7, characterized in that: The stator coil (27) is made of high-purity oxygen-free copper material, combined with corona-resistant H-class insulation material, and is vacuum impregnated with VPI; the two ends of the stator coil (27) are coated with three-proof paint.

9. The high-efficient direct-drive variable-frequency permanent-magnet motor for mud pump according to any one of claims 1-8, characterized in that: One or two of the powerful cooling fans (3) are installed on the top of the motor housing (21).

10. The high-efficiency direct-drive variable-frequency permanent-magnet motor for mud pumps according to claim 9, characterized in that: The powerful cooling fan (3) adopts frequency conversion speed control.

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