A method for remanufacturing an asynchronous motor into a synchronous reluctance motor and the motor itself.

Abstract

This invention discloses a method and a motor for remanufacturing an asynchronous motor into a synchronous reluctance motor, relating to the field of motor remanufacturing and solving the problem of high-efficiency remanufacturing of asynchronous motors. This invention disassembles and recycles most of the materials from old, low-efficiency asynchronous motors, retaining the stator assembly and several accessories. New synchronous reluctance rotor laminations are manufactured and reassembled with the original asynchronous motor's stator assembly and accessories. The newly manufactured synchronous reluctance rotor laminations are equipped with several air grilles. This invention can improve the energy efficiency level of the original motor, achieving the performance of a high-efficiency motor. This technical method can improve the operating efficiency of old motors and make full use of existing materials, significantly reducing costs compared to purchasing a new high-efficiency motor, thus lowering the investment costs for users upgrading to high-efficiency motors.

Description

Technical Field

[0001] This invention relates to the field of motor remanufacturing technology, specifically to a method for remanufacturing an asynchronous motor into a synchronous reluctance motor and the motor itself. Background Technology

[0002] In the face of a escalating global energy crisis and environmental problems, improving energy efficiency has become a key measure for countries to achieve their "dual carbon" goals and promote sustainable development. Asynchronous motors, as one of the most widely used power devices in industrial production and daily life, account for a significant proportion of global electricity consumption. According to relevant statistics, in my country's industrial sector, asynchronous motors consume over 60% of total industrial electricity. Many traditional asynchronous motors in operation suffer from low efficiency due to limitations in design technology and manufacturing processes, resulting in substantial energy waste during operation.

[0003] To improve motor energy efficiency, major motor R&D and manufacturing companies have launched the latest high-efficiency motor products to meet market demand. Currently, common high-efficiency motor technologies include using lower-loss, higher-grade silicon steel cores, replacing cast aluminum asynchronous motor rotors with copper rotors, or using permanent magnet motors, including flat wire windings with lower copper losses, increasing slot fill factor, and reducing copper losses, thereby improving overall motor energy efficiency. While these newly designed and developed high-efficiency motors are advanced in performance indicators and energy efficiency levels, purchasing new high-efficiency motors often requires a large one-time investment. High-efficiency motors are typically 20-30% more expensive than traditional low-efficiency asynchronous motors, which poses a significant obstacle to user adoption and promotion. Against this backdrop, high-efficiency motor remanufacturing technology has emerged. Motor remanufacturing refers to the process of dismantling old, inefficient asynchronous motors that do not meet energy efficiency standards, recycling some materials, and then reprocessing and remanufacturing them. After remanufacturing, these inefficient motors can achieve higher energy efficiency levels. This not only meets national energy efficiency requirements but also lowers the financial barrier for users to upgrade to high-efficiency motors, saves material consumption, reduces carbon emissions during new motor production, achieves resource recycling, and protects the environment. The government has also introduced various policies to support the large-scale and standardized development of the motor remanufacturing industry. These policies provide a favorable policy environment and development opportunities for high-efficiency asynchronous motor remanufacturing and also create an urgent need for upgrading and transforming traditional asynchronous motors.

[0004] From a resource utilization perspective, directly scrapping traditional asynchronous motors after they reach the end of their service life not only wastes a large amount of metal resources (such as copper, iron, and silicon steel sheets), but also pollutes the environment due to improper disposal of motor waste. High-efficiency remanufacturing of asynchronous motors, however, involves a series of technical means such as testing, disassembly, repair, and upgrading of used asynchronous motors, enabling the remanufactured motor to achieve or exceed the performance level of the original motor, and even achieve higher efficiency and energy efficiency ratings. This approach not only effectively conserves metal resources, reduces waste emissions, and minimizes environmental impact, but also significantly reduces equipment procurement costs for enterprises, improving their economic benefits and market competitiveness.

[0005] From a market demand perspective, with the continuous advancement of my country's industrialization and the optimization and upgrading of its industrial structure, more and more industries and enterprises are placing higher demands on the efficiency, reliability, and energy efficiency of motors. Traditional inefficient asynchronous motors can no longer meet the current industrial production's need for high-quality power equipment. Enterprises urgently need to upgrade and transform existing inefficient motors to reduce production costs, improve production efficiency, and achieve green production. At the same time, under the global trend of low-carbon economic development, the international market demand for high-efficiency and energy-saving motors is also constantly growing. High-efficiency remanufactured asynchronous motors can not only meet domestic market demand but also have broad international market prospects.

[0006] From a technological development perspective, significant progress has been made in recent years in areas such as motor design, materials science, and manufacturing processes, providing solid technical support for the high-efficiency remanufacturing of asynchronous motors. For example, the continuous maturation of technologies such as high-grade silicon steel sheets, high-performance permanent magnet materials, and efficient winding manufacturing processes enables the use of more advanced technologies and materials in the remanufacturing process of asynchronous motors, significantly improving motor efficiency and performance. Simultaneously, advancements in motor testing and fault diagnosis technologies have provided strong support for quality control and reliability assurance in the remanufacturing process, ensuring that the quality and performance of remanufactured motors meet relevant standards.

[0007] In conclusion, driven by factors such as energy conservation, policy guidance, resource utilization, market demand, and technological development, high-efficiency remanufacturing of asynchronous motors has become an important direction for the transformation and upgrading of my country's motor industry, with significant practical implications and broad development prospects. Summary of the Invention

[0008] To address the aforementioned problem of high-efficiency remanufacturing of asynchronous motors, this invention proposes a method and a synchronous reluctance motor for remanufacturing asynchronous motors. This invention recycles most of the materials from old, low-efficiency asynchronous motors to manufacture synchronous reluctance motors, thereby improving the energy efficiency level of the original motor to achieve the performance of a high-efficiency motor. This not only enhances the operating efficiency of older motors but also makes full use of existing materials, significantly reducing costs compared to purchasing new high-efficiency motors and lowering the investment costs for users upgrading to high-efficiency motors.

[0009] This invention proposes a method for remanufacturing an asynchronous motor into a synchronous reluctance motor, which specifically includes the following steps: Step 1: Disassemble the asynchronous motor to obtain the asynchronous motor rotor assembly, asynchronous motor stator assembly, and several accessories. Keep the asynchronous motor stator assembly and accessories. Step 2: Disassemble the asynchronous motor rotor assembly to obtain the cast aluminum rotor core, bearings, and shaft. Keep the bearings and shaft, and disassemble and recycle the cast aluminum rotor core. Step 3: Manufacturing synchronous reluctance rotor laminations, and stacking several synchronous reluctance rotor laminations into a synchronous reluctance rotor core; Step 4: Press-fit and remanufacture the synchronous reluctance rotor core, bearings, and shaft into a synchronous reluctance rotor assembly; Step 5: Assemble the synchronous reluctance rotor assembly, the asynchronous motor stator assembly, and several accessories to obtain the synchronous reluctance motor and test it.

[0010] Furthermore, in step two, the aluminum metal from the dismantled cast aluminum rotor core is smelted and recycled, and the dismantled silicon steel sheets are recycled.

[0011] Furthermore, in step three, the synchronous reluctance rotor laminations are uniformly provided with several sets of air grid structures around their circumference, and each set of air grid structures includes several layers of air grids.

[0012] A motor manufactured using the above-mentioned asynchronous motor remanufacturing synchronous reluctance motor method specifically includes two end covers, a stator assembly, and a rotor assembly. The rotor assembly is coaxially rotatably disposed inside the stator assembly. An end cover is disposed at each end of the stator assembly. The end covers and the rotor assembly are rotatably connected.

[0013] Furthermore, the stator assembly includes a housing and a stator core, with the stator core disposed on the inner wall of the housing and windings disposed on the stator core.

[0014] Furthermore, the rotor assembly includes a synchronous reluctance rotor core and a shaft, with the synchronous reluctance rotor core coaxially sleeved on the shaft, and the shaft and end plate rotatably connected.

[0015] Furthermore, dynamic balance plates are provided at both ends of the synchronous reluctance rotor core.

[0016] Furthermore, the synchronous reluctance rotor core includes several synchronous reluctance rotor laminations, and several sets of air grid structures are uniformly arranged on the circumference of the synchronous reluctance rotor laminations, with each set of air grid structures including several layers of air grids.

[0017] Furthermore, the outer circumference of the synchronous reluctance rotor lamination has a wavy structure.

[0018] Furthermore, the shaft and the end plate are connected by bearings.

[0019] The beneficial effects of the method for remanufacturing an asynchronous motor into a synchronous reluctance motor as described in this invention and the motor itself are as follows: (1) The method and motor for remanufacturing an asynchronous motor into a synchronous reluctance motor according to the present invention have the same rotor mechanical speed as the synchronous speed corresponding to the stator electrical frequency. There is no slip rate, so there is no rotor slip loss and rotor iron loss. The motor operating efficiency is significantly improved, and on average, it can be improved by 1-2 energy efficiency levels.

[0020] (2) The asynchronous motor remanufacturing synchronous reluctance motor method and motor described in this invention belong to synchronous motors, but there is no rotor magnetic field provided by permanent magnets. Instead, the torque is maximized by utilizing the difference in inductance between the quadrature axis and the direct axis magnetic circuit on the rotor side. Essentially, it belongs to synchronous reluctance motors. Furthermore, since the rotor does not have permanent magnets and only has silicon steel sheets, the stator assembly and shaft end cover are retained to the greatest extent, so the motor cost is lower.

[0021] (3) The asynchronous motor remanufacturing synchronous reluctance motor method and motor described in this invention, in which the silicon steel sheets rotate synchronously without core loss, can use silicon steel sheets with poor loss characteristics, thereby reducing the cost of motor remanufacturing. Since the rotor loss is close to zero, the rotor heating phenomenon is greatly improved. For high-speed operation, the problem of rotor heating restricting the overall power of the motor is solved, thereby further improving the continuous power of the motor.

[0022] (4) The asynchronous motor remanufacturing synchronous reluctance motor method and motor described in this invention require the use of a frequency converter with a synchronous reluctance motor control algorithm for starting and running, so it is more suitable for loads that require variable frequency speed regulation; or the frequency converter can be used to start and drive to 50Hz power frequency and then switch to the power frequency grid, and the synchronous reluctance torque can be used to achieve power frequency synchronous operation. Attached Figure Description

[0023] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0024] In the attached diagram: Figure 1 This is a flowchart of a method for remanufacturing an asynchronous motor into a synchronous reluctance motor, as described in this invention. Figure 2 This is a schematic diagram of the basic structure of a traditional cast aluminum rotor asynchronous motor; Figure 3 This is a schematic diagram of the basic structure of a synchronous reluctance motor remanufactured by a method for remanufacturing an asynchronous motor and a synchronous reluctance motor according to the present invention. Figure 4 This is a schematic diagram of the structure of a synchronous reluctance rotor lamination manufactured by the method for remanufacturing an asynchronous motor into a synchronous reluctance motor as described in this invention. Among them: 1-bearing, 2-end cover, 3-synchronous reluctance rotor core, 301-synchronous reluctance rotor lamination, 4-winding, 5-housing, 6-stator core, 7-shaft, 8-dynamic balance plate, 9-air grid, 10-cast aluminum guide bar, 11-cast aluminum end ring. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present invention can be combined with each other. The described embodiments are merely some embodiments of the present invention, not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Specific implementation method one: See Figures 1-4 This embodiment is described in detail. The method for remanufacturing an asynchronous motor into a synchronous reluctance motor according to this embodiment specifically includes the following steps: Step 1: Disassemble the asynchronous motor to obtain the asynchronous motor rotor assembly, asynchronous motor stator assembly, end cover 2, and several accessories. The asynchronous motor stator assembly and accessories are retained. The asynchronous motor stator assembly includes the housing 5, stator core 6, and winding 4. The accessories include screws, washers, wave washers, and oil seals, etc. Step 2: Disassemble the asynchronous motor rotor assembly to obtain the cast aluminum rotor core, bearing 1 and shaft 7. Keep bearing 1 and shaft 7. Melt and recycle the aluminum metal from the disassembled cast aluminum rotor core, and recycle the silicon steel sheets from the disassembled parts. Step 3: Manufacturing synchronous reluctance rotor laminations 301. Several sets of air grid structures are evenly arranged on the circumference of the synchronous reluctance rotor laminations 301. Each set of air grid structures includes several layers of air grids 9. Several synchronous reluctance rotor laminations 301 are stacked to form a synchronous reluctance rotor core 3. Step 4: Press-fit and remanufacture the synchronous reluctance rotor core 3, bearing 1 and shaft 7 into a synchronous reluctance rotor assembly; Step 5: Assemble the synchronous reluctance rotor assembly, the asynchronous motor stator assembly, and several accessories to obtain the synchronous reluctance motor and test it.

[0027] A motor manufactured using the above-mentioned asynchronous motor remanufacturing synchronous reluctance motor method specifically includes two end covers 2, a stator assembly and a rotor assembly, wherein the rotor assembly is coaxially rotatably disposed inside the stator assembly; an end cover 2 is disposed at each end of the stator assembly; the end cover 2 and the rotor assembly are rotatably connected.

[0028] The stator assembly includes a housing 5 and a stator core 6. The stator core 6 is disposed on the inner wall of the housing 5, and a winding 4 is disposed on the stator core 6.

[0029] The rotor assembly includes a synchronous reluctance rotor core 3 and a rotating shaft 7. The synchronous reluctance rotor core 3 is coaxially mounted on the rotating shaft 7, and the rotating shaft 7 and the end cover 2 are rotatably connected by bearings 1. Dynamic balance plates 8 are provided at both ends of the synchronous reluctance rotor core 3.

[0030] The synchronous reluctance rotor core 3 includes several synchronous reluctance rotor laminations 301. Several sets of air grid structures are evenly arranged around the circumference of each synchronous reluctance rotor lamination 301. Each set of air grid structures includes several layers of air grids 9. The air grids 9 are V-shaped, U-shaped, or can be straight or irregular multi-layered arc structures, but the number of poles corresponding to the air grid 9 must be consistent with the number of poles of the matching asynchronous motor stator core and windings. Each set of air grids 9 exhibits central symmetry. The size of the magnetic isolation bridge at the edge of the air grid 9 must ensure the mechanical strength of the synchronous reluctance rotor core 3 at its highest operating speed and ensure a low leakage flux coefficient.

[0031] The number of air grille 9 layers, the thickness of each air grille 9 layer, and the thickness of adjacent silicon steel sheet grilles can be flexibly adjusted. However, while maintaining mechanical strength, the ratio and difference between quadrature axis inductance and direct axis inductance should be maximized to achieve maximum output of reluctance torque. It is common to use 3-4 layers of air grille 9.

[0032] In order to achieve sinusoidal air gap magnetic field, the synchronous reluctance rotor lamination 301 with air grille 9 can adopt a non-uniform air gap structure, that is, the outer circle of the synchronous reluctance rotor lamination 301 is designed as a wave-shaped structure.

[0033] The specific remanufacturing process of the asynchronous motor remanufacturing synchronous reluctance motor method described in this embodiment is as follows: Transforming a traditional asynchronous motor into a synchronous reluctance motor involves, in practice, retaining the main structural components such as the motor housing 5, shaft 7, end cover 2, and bearing 1 (provided these components are free from mechanical damage and performance loss and can be used normally). The stator core 6 and winding 4 are also retained. The main change is the removal of the cast aluminum rotor core, which is made of cast aluminum, and its replacement with a synchronous reluctance rotor core 3 made of rotor laminations with a multi-layered air grid structure. Dynamic balancing plates 8 are then pressed onto both sides, and the disassembled bearing 1 is re-pressed onto the shaft 7. The synchronous reluctance motor rotor assembly is then assembled with the asynchronous motor stator assembly and accessories such as the end cover 2. After offline testing, a high-efficiency synchronous reluctance motor is obtained. This remanufactured motor is a synchronous motor, operating at the synchronous speed corresponding to the power supply frequency. During actual operation, it does not exhibit rotor slip loss like asynchronous motors, nor does it suffer from eddy current losses like permanent magnet motors; the rotor loss is approximately zero. Figure 2 and Figure 3 The diagram shows the internal structure of a traditional cast aluminum rotor asynchronous motor and the internal structure of a remanufactured synchronous reluctance motor. As can be seen from the comparison, apart from replacing the rotor core with a cast aluminum rotor, other structural components are reused to the greatest extent. Furthermore, the replaced synchronous reluctance rotor core 3 does not contain permanent magnets, copper, aluminum, or other materials; it only has a core made of stacked silicon steel sheets. Since the synchronous reluctance rotor core 3 rotates synchronously with the magnetic field, the rotor iron loss is very low. Therefore, the requirements for the rotor silicon steel sheet core are very low, and low-cost silicon steel sheets with a thickness of 0.5mm-1mm and higher losses can be used. Figure 1 The diagram shows the manufacturing process for remanufacturing an asynchronous motor into a synchronous reluctance motor. Figure 4 The image shows a typical structure of the replaced synchronous reluctance rotor lamination 301 with an air grid structure.

[0034] In summary, the asynchronous motor remanufacturing synchronous reluctance motor method and motor described in this invention have the same rotor mechanical speed as the synchronous speed corresponding to the stator electrical frequency, and there is no slip rate. Therefore, there is no rotor slip loss and rotor iron loss, and the motor operating efficiency is significantly improved, which can improve the energy efficiency level by an average of 1-2 levels.

[0035] The present invention discloses a method for remanufacturing an asynchronous motor into a synchronous reluctance motor and a motor thereof. The motor belongs to the category of synchronous motors, but it does not have a rotor magnetic field provided by permanent magnets. Instead, it utilizes the asymmetry between the quadrature and direct axis magnetic circuits on the rotor side to obtain the difference in quadrature and direct axis inductances to maximize torque output. Essentially, it belongs to the category of synchronous reluctance motors. Furthermore, since the rotor does not have permanent magnets and only has silicon steel sheets, it retains the stator assembly and shaft end cover and other structures to the greatest extent, thus reducing the cost of the motor.

[0036] The present invention discloses a method and motor for remanufacturing an asynchronous motor into a synchronous reluctance motor. Since the synchronous rotation of silicon steel sheets eliminates core losses, silicon steel sheets with poor loss characteristics can be used, thereby reducing the remanufacturing cost of the motor. Because rotor losses are approximately zero, rotor heating is significantly reduced. For high-speed operation, the problem of rotor heating limiting the overall power of the motor is solved, thus further improving the continuous power of the motor.

[0037] The present invention discloses a method and motor for remanufacturing an asynchronous motor into a synchronous reluctance motor. It requires a frequency converter with a synchronous reluctance motor control algorithm for starting and running, and is therefore more suitable for load applications that require variable frequency speed regulation. Alternatively, it can be started by a frequency converter and driven to the 50Hz power frequency before being switched to the power frequency grid, and synchronous operation at the power frequency is achieved by using the synchronous reluctance torque.

[0038] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the invention. They can also be reasonable combinations of the features described in the above embodiments. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for remanufacturing an asynchronous motor into a synchronous reluctance motor, characterized in that: Includes the following steps: Step 1: Disassemble the asynchronous motor to obtain the asynchronous motor rotor assembly, asynchronous motor stator assembly, and several accessories. Keep the asynchronous motor stator assembly and accessories. Step 2: Disassemble the asynchronous motor rotor assembly to obtain the cast aluminum rotor core, bearing (1) and shaft (7). Keep the bearing (1) and shaft (7) and disassemble and recycle the cast aluminum rotor core. Step 3: Manufacturing synchronous reluctance rotor laminations (301), and stacking several synchronous reluctance rotor laminations (301) into a synchronous reluctance rotor core (3). Step 4: Press-fit and remanufacture the synchronous reluctance rotor core (3), bearing (1) and shaft (7) into a synchronous reluctance rotor assembly; Step 5: Assemble the synchronous reluctance rotor assembly, the asynchronous motor stator assembly, and several accessories to obtain the synchronous reluctance motor and test it.

2. The method for remanufacturing an asynchronous motor into a synchronous reluctance motor according to claim 1, characterized in that: In step two, the aluminum metal from the dismantled cast aluminum rotor core is smelted and recycled, and the silicon steel sheets from the dismantling are recycled.

3. The method for remanufacturing an asynchronous motor into a synchronous reluctance motor according to claim 1, characterized in that: In step three, the synchronous reluctance rotor lamination (301) has several sets of air grid structures evenly arranged on its circumference, and each set of air grid structures includes several layers of air grids (9).

4. A motor manufactured using the method for remanufacturing an asynchronous motor into a synchronous reluctance motor as described in claim 1, characterized in that: It includes two end caps (2), a stator assembly and a rotor assembly. The rotor assembly is coaxially rotatably mounted inside the stator assembly. An end cap (2) is provided at each end of the stator assembly. The end caps (2) and the rotor assembly are rotatably connected.

5. The motor according to claim 4, characterized in that: The stator assembly includes a housing (5) and a stator core (6). The stator core (6) is disposed on the inner wall of the housing (5), and a winding (4) is disposed on the stator core (6).

6. The motor according to claim 4, characterized in that: The rotor assembly includes a synchronous reluctance rotor core (3) and a rotating shaft (7). The synchronous reluctance rotor core (3) is coaxially sleeved on the rotating shaft (7), and the rotating shaft (7) and the end cover (2) are rotatably connected.

7. The motor according to claim 6, characterized in that: Dynamic balance plates (8) are provided at both ends of the synchronous reluctance rotor core (3).

8. The motor according to claim 6 or 7, characterized in that: The synchronous reluctance rotor core (3) includes several synchronous reluctance rotor laminations (301). Several sets of air grid structures are uniformly arranged on the circumference of the synchronous reluctance rotor laminations (301), and each set of air grid structures includes several layers of air grids (9).

9. The motor according to claim 8, characterized in that: The outer circle of the synchronous reluctance rotor lamination (301) has a wave-shaped structure.

10. The motor according to claim 6, characterized in that: The shaft (7) and the end cap (2) are connected by a bearing (1).

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